Green shading in the line number column means the source is part of the translation unit, red means it is conditionally excluded. Highlighted line numbers link to the translation unit page. Highlighted macros link to the macro page.
1: #ifndef _LINUX_FS_H 2: #define _LINUX_FS_H 3: 4: 5: #include <linux/linkage.h> 6: #include <linux/wait.h> 7: #include <linux/kdev_t.h> 8: #include <linux/dcache.h> 9: #include <linux/path.h> 10: #include <linux/stat.h> 11: #include <linux/cache.h> 12: #include <linux/list.h> 13: #include <linux/list_lru.h> 14: #include <linux/llist.h> 15: #include <linux/radix-tree.h> 16: #include <linux/rbtree.h> 17: #include <linux/init.h> 18: #include <linux/pid.h> 19: #include <linux/bug.h> 20: #include <linux/mutex.h> 21: #include <linux/capability.h> 22: #include <linux/semaphore.h> 23: #include <linux/fiemap.h> 24: #include <linux/rculist_bl.h> 25: #include <linux/atomic.h> 26: #include <linux/shrinker.h> 27: #include <linux/migrate_mode.h> 28: #include <linux/uidgid.h> 29: #include <linux/lockdep.h> 30: #include <linux/percpu-rwsem.h> 31: #include <linux/blk_types.h> 32: 33: #include <asm/byteorder.h> 34: #include <uapi/linux/fs.h> 35: 36: struct export_operations; 37: struct hd_geometry; 38: struct iovec; 39: struct nameidata; 40: struct kiocb; 41: struct kobject; 42: struct pipe_inode_info; 43: struct poll_table_struct; 44: struct kstatfs; 45: struct vm_area_struct; 46: struct vfsmount; 47: struct cred; 48: struct swap_info_struct; 49: struct seq_file; 50: struct workqueue_struct; 51: 52: extern void __init inode_init(void); 53: extern void __init inode_init_early(void); 54: extern void __init files_init(unsigned long); 55: 56: extern struct files_stat_struct files_stat; 57: extern unsigned long get_max_files(void); 58: extern int sysctl_nr_open; 59: extern struct inodes_stat_t inodes_stat; 60: extern int leases_enable, lease_break_time; 61: extern int sysctl_protected_symlinks; 62: extern int sysctl_protected_hardlinks; 63: 64: struct buffer_head; 65: typedef int (get_block_t)(struct inode *inode, sector_t iblock, 66: struct buffer_head *bh_result, int create); 67: typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset, 68: ssize_t bytes, void *private); 69: 70: #define MAY_EXEC 0x00000001 71: #define MAY_WRITE 0x00000002 72: #define MAY_READ 0x00000004 73: #define MAY_APPEND 0x00000008 74: #define MAY_ACCESS 0x00000010 75: #define MAY_OPEN 0x00000020 76: #define MAY_CHDIR 0x00000040 77: /* called from RCU mode, don't block */ 78: #define MAY_NOT_BLOCK 0x00000080 79: 80: /* 81: * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond 82: * to O_WRONLY and O_RDWR via the strange trick in __dentry_open() 83: */ 84: 85: /* file is open for reading */ 86: #define FMODE_READ ((__force fmode_t)0x1) 87: /* file is open for writing */ 88: #define FMODE_WRITE ((__force fmode_t)0x2) 89: /* file is seekable */ 90: #define FMODE_LSEEK ((__force fmode_t)0x4) 91: /* file can be accessed using pread */ 92: #define FMODE_PREAD ((__force fmode_t)0x8) 93: /* file can be accessed using pwrite */ 94: #define FMODE_PWRITE ((__force fmode_t)0x10) 95: /* File is opened for execution with sys_execve / sys_uselib */ 96: #define FMODE_EXEC ((__force fmode_t)0x20) 97: /* File is opened with O_NDELAY (only set for block devices) */ 98: #define FMODE_NDELAY ((__force fmode_t)0x40) 99: /* File is opened with O_EXCL (only set for block devices) */ 100: #define FMODE_EXCL ((__force fmode_t)0x80) 101: /* File is opened using open(.., 3, ..) and is writeable only for ioctls 102: (specialy hack for floppy.c) */ 103: #define FMODE_WRITE_IOCTL ((__force fmode_t)0x100) 104: /* 32bit hashes as llseek() offset (for directories) */ 105: #define FMODE_32BITHASH ((__force fmode_t)0x200) 106: /* 64bit hashes as llseek() offset (for directories) */ 107: #define FMODE_64BITHASH ((__force fmode_t)0x400) 108: 109: /* 110: * Don't update ctime and mtime. 111: * 112: * Currently a special hack for the XFS open_by_handle ioctl, but we'll 113: * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon. 114: */ 115: #define FMODE_NOCMTIME ((__force fmode_t)0x800) 116: 117: /* Expect random access pattern */ 118: #define FMODE_RANDOM ((__force fmode_t)0x1000) 119: 120: /* File is huge (eg. /dev/kmem): treat loff_t as unsigned */ 121: #define FMODE_UNSIGNED_OFFSET ((__force fmode_t)0x2000) 122: 123: /* File is opened with O_PATH; almost nothing can be done with it */ 124: #define FMODE_PATH ((__force fmode_t)0x4000) 125: 126: /* File was opened by fanotify and shouldn't generate fanotify events */ 127: #define FMODE_NONOTIFY ((__force fmode_t)0x1000000) 128: 129: /* 130: * Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector 131: * that indicates that they should check the contents of the iovec are 132: * valid, but not check the memory that the iovec elements 133: * points too. 134: */ 135: #define CHECK_IOVEC_ONLY -1 136: 137: /* 138: * The below are the various read and write types that we support. Some of 139: * them include behavioral modifiers that send information down to the 140: * block layer and IO scheduler. Terminology: 141: * 142: * The block layer uses device plugging to defer IO a little bit, in 143: * the hope that we will see more IO very shortly. This increases 144: * coalescing of adjacent IO and thus reduces the number of IOs we 145: * have to send to the device. It also allows for better queuing, 146: * if the IO isn't mergeable. If the caller is going to be waiting 147: * for the IO, then he must ensure that the device is unplugged so 148: * that the IO is dispatched to the driver. 149: * 150: * All IO is handled async in Linux. This is fine for background 151: * writes, but for reads or writes that someone waits for completion 152: * on, we want to notify the block layer and IO scheduler so that they 153: * know about it. That allows them to make better scheduling 154: * decisions. So when the below references 'sync' and 'async', it 155: * is referencing this priority hint. 156: * 157: * With that in mind, the available types are: 158: * 159: * READ A normal read operation. Device will be plugged. 160: * READ_SYNC A synchronous read. Device is not plugged, caller can 161: * immediately wait on this read without caring about 162: * unplugging. 163: * READA Used for read-ahead operations. Lower priority, and the 164: * block layer could (in theory) choose to ignore this 165: * request if it runs into resource problems. 166: * WRITE A normal async write. Device will be plugged. 167: * WRITE_SYNC Synchronous write. Identical to WRITE, but passes down 168: * the hint that someone will be waiting on this IO 169: * shortly. The write equivalent of READ_SYNC. 170: * WRITE_ODIRECT Special case write for O_DIRECT only. 171: * WRITE_FLUSH Like WRITE_SYNC but with preceding cache flush. 172: * WRITE_FUA Like WRITE_SYNC but data is guaranteed to be on 173: * non-volatile media on completion. 174: * WRITE_FLUSH_FUA Combination of WRITE_FLUSH and FUA. The IO is preceded 175: * by a cache flush and data is guaranteed to be on 176: * non-volatile media on completion. 177: * 178: */ 179: #define RW_MASK REQ_WRITE 180: #define RWA_MASK REQ_RAHEAD 181: 182: #define READ 0 183: #define WRITE RW_MASK 184: #define READA RWA_MASK 185: #define KERNEL_READ (READ|REQ_KERNEL) 186: #define KERNEL_WRITE (WRITE|REQ_KERNEL) 187: 188: #define READ_SYNC (READ | REQ_SYNC) 189: #define WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE) 190: #define WRITE_ODIRECT (WRITE | REQ_SYNC) 191: #define WRITE_FLUSH (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH) 192: #define WRITE_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FUA) 193: #define WRITE_FLUSH_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | REQ_FUA) 194: 195: /* 196: * Attribute flags. These should be or-ed together to figure out what 197: * has been changed! 198: */ 199: #define ATTR_MODE (1 << 0) 200: #define ATTR_UID (1 << 1) 201: #define ATTR_GID (1 << 2) 202: #define ATTR_SIZE (1 << 3) 203: #define ATTR_ATIME (1 << 4) 204: #define ATTR_MTIME (1 << 5) 205: #define ATTR_CTIME (1 << 6) 206: #define ATTR_ATIME_SET (1 << 7) 207: #define ATTR_MTIME_SET (1 << 8) 208: #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */ 209: #define ATTR_ATTR_FLAG (1 << 10) 210: #define ATTR_KILL_SUID (1 << 11) 211: #define ATTR_KILL_SGID (1 << 12) 212: #define ATTR_FILE (1 << 13) 213: #define ATTR_KILL_PRIV (1 << 14) 214: #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */ 215: #define ATTR_TIMES_SET (1 << 16) 216: 217: /* 218: * This is the Inode Attributes structure, used for notify_change(). It 219: * uses the above definitions as flags, to know which values have changed. 220: * Also, in this manner, a Filesystem can look at only the values it cares 221: * about. Basically, these are the attributes that the VFS layer can 222: * request to change from the FS layer. 223: * 224: * Derek Atkins <warlord@MIT.EDU> 94-10-20 225: */ 226: struct iattr { 227: unsigned int ia_valid; 228: umode_t ia_mode; 229: kuid_t ia_uid; 230: kgid_t ia_gid; 231: loff_t ia_size; 232: struct timespec ia_atime; 233: struct timespec ia_mtime; 234: struct timespec ia_ctime; 235: 236: /* 237: * Not an attribute, but an auxiliary info for filesystems wanting to 238: * implement an ftruncate() like method. NOTE: filesystem should 239: * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL). 240: */ 241: struct file *ia_file; 242: }; 243: 244: /* 245: * Includes for diskquotas. 246: */ 247: #include <linux/quota.h> 248: 249: /** 250: * enum positive_aop_returns - aop return codes with specific semantics 251: * 252: * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has 253: * completed, that the page is still locked, and 254: * should be considered active. The VM uses this hint 255: * to return the page to the active list -- it won't 256: * be a candidate for writeback again in the near 257: * future. Other callers must be careful to unlock 258: * the page if they get this return. Returned by 259: * writepage(); 260: * 261: * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has 262: * unlocked it and the page might have been truncated. 263: * The caller should back up to acquiring a new page and 264: * trying again. The aop will be taking reasonable 265: * precautions not to livelock. If the caller held a page 266: * reference, it should drop it before retrying. Returned 267: * by readpage(). 268: * 269: * address_space_operation functions return these large constants to indicate 270: * special semantics to the caller. These are much larger than the bytes in a 271: * page to allow for functions that return the number of bytes operated on in a 272: * given page. 273: */ 274: 275: enum positive_aop_returns { 276: AOP_WRITEPAGE_ACTIVATE = 0x80000, 277: AOP_TRUNCATED_PAGE = 0x80001, 278: }; 279: 280: #define AOP_FLAG_UNINTERRUPTIBLE 0x0001 /* will not do a short write */ 281: #define AOP_FLAG_CONT_EXPAND 0x0002 /* called from cont_expand */ 282: #define AOP_FLAG_NOFS 0x0004 /* used by filesystem to direct 283: * helper code (eg buffer layer) 284: * to clear GFP_FS from alloc */ 285: 286: /* 287: * oh the beauties of C type declarations. 288: */ 289: struct page; 290: struct address_space; 291: struct writeback_control; 292: 293: struct iov_iter { 294: const struct iovec *iov; 295: unsigned long nr_segs; 296: size_t iov_offset; 297: size_t count; 298: }; 299: 300: size_t iov_iter_copy_from_user_atomic(struct page *page, 301: struct iov_iter *i, unsigned long offset, size_t bytes); 302: size_t iov_iter_copy_from_user(struct page *page, 303: struct iov_iter *i, unsigned long offset, size_t bytes); 304: void iov_iter_advance(struct iov_iter *i, size_t bytes); 305: int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes); 306: size_t iov_iter_single_seg_count(const struct iov_iter *i); 307: 308: static inline void iov_iter_init(struct iov_iter *i, 309: const struct iovec *iov, unsigned long nr_segs, 310: size_t count, size_t written) 311: { 312: i->iov = iov; 313: i->nr_segs = nr_segs; 314: i->iov_offset = 0; 315: i->count = count + written; 316: 317: iov_iter_advance(i, written); 318: } 319: 320: static inline size_t iov_iter_count(struct iov_iter *i) 321: { 322: return i->count; 323: } 324: 325: /* 326: * "descriptor" for what we're up to with a read. 327: * This allows us to use the same read code yet 328: * have multiple different users of the data that 329: * we read from a file. 330: * 331: * The simplest case just copies the data to user 332: * mode. 333: */ 334: typedef struct { 335: size_t written; 336: size_t count; 337: union { 338: char __user *buf; 339: void *data; 340: } arg; 341: int error; 342: } read_descriptor_t; 343: 344: typedef int (*read_actor_t)(read_descriptor_t *, struct page *, 345: unsigned long, unsigned long); 346: 347: struct address_space_operations { 348: int (*writepage)(struct page *page, struct writeback_control *wbc); 349: int (*readpage)(struct file *, struct page *); 350: 351: /* Write back some dirty pages from this mapping. */ 352: int (*writepages)(struct address_space *, struct writeback_control *); 353: 354: /* Set a page dirty. Return true if this dirtied it */ 355: int (*set_page_dirty)(struct page *page); 356: 357: int (*readpages)(struct file *filp, struct address_space *mapping, 358: struct list_head *pages, unsigned nr_pages); 359: 360: int (*write_begin)(struct file *, struct address_space *mapping, 361: loff_t pos, unsigned len, unsigned flags, 362: struct page **pagep, void **fsdata); 363: int (*write_end)(struct file *, struct address_space *mapping, 364: loff_t pos, unsigned len, unsigned copied, 365: struct page *page, void *fsdata); 366: 367: /* Unfortunately this kludge is needed for FIBMAP. Don't use it */ 368: sector_t (*bmap)(struct address_space *, sector_t); 369: void (*invalidatepage) (struct page *, unsigned int, unsigned int); 370: int (*releasepage) (struct page *, gfp_t); 371: void (*freepage)(struct page *); 372: ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov, 373: loff_t offset, unsigned long nr_segs); 374: int (*get_xip_mem)(struct address_space *, pgoff_t, int, 375: void **, unsigned long *); 376: /* 377: * migrate the contents of a page to the specified target. If 378: * migrate_mode is MIGRATE_ASYNC, it must not block. 379: */ 380: int (*migratepage) (struct address_space *, 381: struct page *, struct page *, enum migrate_mode); 382: int (*launder_page) (struct page *); 383: int (*is_partially_uptodate) (struct page *, read_descriptor_t *, 384: unsigned long); 385: void (*is_dirty_writeback) (struct page *, bool *, bool *); 386: int (*error_remove_page)(struct address_space *, struct page *); 387: 388: /* swapfile support */ 389: int (*swap_activate)(struct swap_info_struct *sis, struct file *file, 390: sector_t *span); 391: void (*swap_deactivate)(struct file *file); 392: }; 393: 394: extern const struct address_space_operations empty_aops; 395: 396: /* 397: * pagecache_write_begin/pagecache_write_end must be used by general code 398: * to write into the pagecache. 399: */ 400: int pagecache_write_begin(struct file *, struct address_space *mapping, 401: loff_t pos, unsigned len, unsigned flags, 402: struct page **pagep, void **fsdata); 403: 404: int pagecache_write_end(struct file *, struct address_space *mapping, 405: loff_t pos, unsigned len, unsigned copied, 406: struct page *page, void *fsdata); 407: 408: struct backing_dev_info; 409: struct address_space { 410: struct inode *host; /* owner: inode, block_device */ 411: struct radix_tree_root page_tree; /* radix tree of all pages */ 412: spinlock_t tree_lock; /* and lock protecting it */ 413: unsigned int i_mmap_writable;/* count VM_SHARED mappings */ 414: struct rb_root i_mmap; /* tree of private and shared mappings */ 415: struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */ 416: struct mutex i_mmap_mutex; /* protect tree, count, list */ 417: /* Protected by tree_lock together with the radix tree */ 418: unsigned long nrpages; /* number of total pages */ 419: pgoff_t writeback_index;/* writeback starts here */ 420: const struct address_space_operations *a_ops; /* methods */ 421: unsigned long flags; /* error bits/gfp mask */ 422: struct backing_dev_info *backing_dev_info; /* device readahead, etc */ 423: spinlock_t private_lock; /* for use by the address_space */ 424: struct list_head private_list; /* ditto */ 425: void *private_data; /* ditto */ 426: } __attribute__((aligned(sizeof(long)))); 427: /* 428: * On most architectures that alignment is already the case; but 429: * must be enforced here for CRIS, to let the least significant bit 430: * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON. 431: */ 432: struct request_queue; 433: 434: struct block_device { 435: dev_t bd_dev; /* not a kdev_t - it's a search key */ 436: int bd_openers; 437: struct inode * bd_inode; /* will die */ 438: struct super_block * bd_super; 439: struct mutex bd_mutex; /* open/close mutex */ 440: struct list_head bd_inodes; 441: void * bd_claiming; 442: void * bd_holder; 443: int bd_holders; 444: bool bd_write_holder; 445: #ifdef CONFIG_SYSFS 446: struct list_head bd_holder_disks; 447: #endif 448: struct block_device * bd_contains; 449: unsigned bd_block_size; 450: struct hd_struct * bd_part; 451: /* number of times partitions within this device have been opened. */ 452: unsigned bd_part_count; 453: int bd_invalidated; 454: struct gendisk * bd_disk; 455: struct request_queue * bd_queue; 456: struct list_head bd_list; 457: /* 458: * Private data. You must have bd_claim'ed the block_device 459: * to use this. NOTE: bd_claim allows an owner to claim 460: * the same device multiple times, the owner must take special 461: * care to not mess up bd_private for that case. 462: */ 463: unsigned long bd_private; 464: 465: /* The counter of freeze processes */ 466: int bd_fsfreeze_count; 467: /* Mutex for freeze */ 468: struct mutex bd_fsfreeze_mutex; 469: }; 470: 471: /* 472: * Radix-tree tags, for tagging dirty and writeback pages within the pagecache 473: * radix trees 474: */ 475: #define PAGECACHE_TAG_DIRTY 0 476: #define PAGECACHE_TAG_WRITEBACK 1 477: #define PAGECACHE_TAG_TOWRITE 2 478: 479: int mapping_tagged(struct address_space *mapping, int tag); 480: 481: /* 482: * Might pages of this file be mapped into userspace? 483: */ 484: static inline int mapping_mapped(struct address_space *mapping) 485: { 486: return !RB_EMPTY_ROOT(&mapping->i_mmap) || 487: !list_empty(&mapping->i_mmap_nonlinear); 488: } 489: 490: /* 491: * Might pages of this file have been modified in userspace? 492: * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff 493: * marks vma as VM_SHARED if it is shared, and the file was opened for 494: * writing i.e. vma may be mprotected writable even if now readonly. 495: */ 496: static inline int mapping_writably_mapped(struct address_space *mapping) 497: { 498: return mapping->i_mmap_writable != 0; 499: } 500: 501: /* 502: * Use sequence counter to get consistent i_size on 32-bit processors. 503: */ 504: #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 505: #include <linux/seqlock.h> 506: #define __NEED_I_SIZE_ORDERED 507: #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount) 508: #else 509: #define i_size_ordered_init(inode) do { } while (0) 510: #endif 511: 512: struct posix_acl; 513: #define ACL_NOT_CACHED ((void *)(-1)) 514: 515: #define IOP_FASTPERM 0x0001 516: #define IOP_LOOKUP 0x0002 517: #define IOP_NOFOLLOW 0x0004 518: 519: /* 520: * Keep mostly read-only and often accessed (especially for 521: * the RCU path lookup and 'stat' data) fields at the beginning 522: * of the 'struct inode' 523: */ 524: struct inode { 525: umode_t i_mode; 526: unsigned short i_opflags; 527: kuid_t i_uid; 528: kgid_t i_gid; 529: unsigned int i_flags; 530: 531: #ifdef CONFIG_FS_POSIX_ACL 532: struct posix_acl *i_acl; 533: struct posix_acl *i_default_acl; 534: #endif 535: 536: const struct inode_operations *i_op; 537: struct super_block *i_sb; 538: struct address_space *i_mapping; 539: 540: #ifdef CONFIG_SECURITY 541: void *i_security; 542: #endif 543: 544: /* Stat data, not accessed from path walking */ 545: unsigned long i_ino; 546: /* 547: * Filesystems may only read i_nlink directly. They shall use the 548: * following functions for modification: 549: * 550: * (set|clear|inc|drop)_nlink 551: * inode_(inc|dec)_link_count 552: */ 553: union { 554: const unsigned int i_nlink; 555: unsigned int __i_nlink; 556: }; 557: dev_t i_rdev; 558: loff_t i_size; 559: struct timespec i_atime; 560: struct timespec i_mtime; 561: struct timespec i_ctime; 562: spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */ 563: unsigned short i_bytes; 564: unsigned int i_blkbits; 565: blkcnt_t i_blocks; 566: 567: #ifdef __NEED_I_SIZE_ORDERED 568: seqcount_t i_size_seqcount; 569: #endif 570: 571: /* Misc */ 572: unsigned long i_state; 573: struct mutex i_mutex; 574: 575: unsigned long dirtied_when; /* jiffies of first dirtying */ 576: 577: struct hlist_node i_hash; 578: struct list_head i_wb_list; /* backing dev IO list */ 579: struct list_head i_lru; /* inode LRU list */ 580: struct list_head i_sb_list; 581: union { 582: struct hlist_head i_dentry; 583: struct rcu_head i_rcu; 584: }; 585: u64 i_version; 586: atomic_t i_count; 587: atomic_t i_dio_count; 588: atomic_t i_writecount; 589: const struct file_operations *i_fop; /* former ->i_op->default_file_ops */ 590: struct file_lock *i_flock; 591: struct address_space i_data; 592: #ifdef CONFIG_QUOTA 593: struct dquot *i_dquot[MAXQUOTAS]; 594: #endif 595: struct list_head i_devices; 596: union { 597: struct pipe_inode_info *i_pipe; 598: struct block_device *i_bdev; 599: struct cdev *i_cdev; 600: }; 601: 602: __u32 i_generation; 603: 604: #ifdef CONFIG_FSNOTIFY 605: __u32 i_fsnotify_mask; /* all events this inode cares about */ 606: struct hlist_head i_fsnotify_marks; 607: #endif 608: 609: #ifdef CONFIG_IMA 610: atomic_t i_readcount; /* struct files open RO */ 611: #endif 612: void *i_private; /* fs or device private pointer */ 613: }; 614: 615: static inline int inode_unhashed(struct inode *inode) 616: { 617: return hlist_unhashed(&inode->i_hash); 618: } 619: 620: /* 621: * inode->i_mutex nesting subclasses for the lock validator: 622: * 623: * 0: the object of the current VFS operation 624: * 1: parent 625: * 2: child/target 626: * 3: xattr 627: * 4: second non-directory 628: * The last is for certain operations (such as rename) which lock two 629: * non-directories at once. 630: * 631: * The locking order between these classes is 632: * parent -> child -> normal -> xattr -> second non-directory 633: */ 634: enum inode_i_mutex_lock_class 635: { 636: I_MUTEX_NORMAL, 637: I_MUTEX_PARENT, 638: I_MUTEX_CHILD, 639: I_MUTEX_XATTR, 640: I_MUTEX_NONDIR2 641: }; 642: 643: void lock_two_nondirectories(struct inode *, struct inode*); 644: void unlock_two_nondirectories(struct inode *, struct inode*); 645: 646: /* 647: * NOTE: in a 32bit arch with a preemptable kernel and 648: * an UP compile the i_size_read/write must be atomic 649: * with respect to the local cpu (unlike with preempt disabled), 650: * but they don't need to be atomic with respect to other cpus like in 651: * true SMP (so they need either to either locally disable irq around 652: * the read or for example on x86 they can be still implemented as a 653: * cmpxchg8b without the need of the lock prefix). For SMP compiles 654: * and 64bit archs it makes no difference if preempt is enabled or not. 655: */ 656: static inline loff_t i_size_read(const struct inode *inode) 657: { 658: #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 659: loff_t i_size; 660: unsigned int seq; 661: 662: do { 663: seq = read_seqcount_begin(&inode->i_size_seqcount); 664: i_size = inode->i_size; 665: } while (read_seqcount_retry(&inode->i_size_seqcount, seq)); 666: return i_size; 667: #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT) 668: loff_t i_size; 669: 670: preempt_disable(); 671: i_size = inode->i_size; 672: preempt_enable(); 673: return i_size; 674: #else 675: return inode->i_size; 676: #endif 677: } 678: 679: /* 680: * NOTE: unlike i_size_read(), i_size_write() does need locking around it 681: * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount 682: * can be lost, resulting in subsequent i_size_read() calls spinning forever. 683: */ 684: static inline void i_size_write(struct inode *inode, loff_t i_size) 685: { 686: #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 687: preempt_disable(); 688: write_seqcount_begin(&inode->i_size_seqcount); 689: inode->i_size = i_size; 690: write_seqcount_end(&inode->i_size_seqcount); 691: preempt_enable(); 692: #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT) 693: preempt_disable(); 694: inode->i_size = i_size; 695: preempt_enable(); 696: #else 697: inode->i_size = i_size; 698: #endif 699: } 700: 701: /* Helper functions so that in most cases filesystems will 702: * not need to deal directly with kuid_t and kgid_t and can 703: * instead deal with the raw numeric values that are stored 704: * in the filesystem. 705: */ 706: static inline uid_t i_uid_read(const struct inode *inode) 707: { 708: return from_kuid(&init_user_ns, inode->i_uid); 709: } 710: 711: static inline gid_t i_gid_read(const struct inode *inode) 712: { 713: return from_kgid(&init_user_ns, inode->i_gid); 714: } 715: 716: static inline void i_uid_write(struct inode *inode, uid_t uid) 717: { 718: inode->i_uid = make_kuid(&init_user_ns, uid); 719: } 720: 721: static inline void i_gid_write(struct inode *inode, gid_t gid) 722: { 723: inode->i_gid = make_kgid(&init_user_ns, gid); 724: } 725: 726: static inline unsigned iminor(const struct inode *inode) 727: { 728: return MINOR(inode->i_rdev); 729: } 730: 731: static inline unsigned imajor(const struct inode *inode) 732: { 733: return MAJOR(inode->i_rdev); 734: } 735: 736: extern struct block_device *I_BDEV(struct inode *inode); 737: 738: struct fown_struct { 739: rwlock_t lock; /* protects pid, uid, euid fields */ 740: struct pid *pid; /* pid or -pgrp where SIGIO should be sent */ 741: enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */ 742: kuid_t uid, euid; /* uid/euid of process setting the owner */ 743: int signum; /* posix.1b rt signal to be delivered on IO */ 744: }; 745: 746: /* 747: * Track a single file's readahead state 748: */ 749: struct file_ra_state { 750: pgoff_t start; /* where readahead started */ 751: unsigned int size; /* # of readahead pages */ 752: unsigned int async_size; /* do asynchronous readahead when 753: there are only # of pages ahead */ 754: 755: unsigned int ra_pages; /* Maximum readahead window */ 756: unsigned int mmap_miss; /* Cache miss stat for mmap accesses */ 757: loff_t prev_pos; /* Cache last read() position */ 758: }; 759: 760: /* 761: * Check if @index falls in the readahead windows. 762: */ 763: static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index) 764: { 765: return (index >= ra->start && 766: index < ra->start + ra->size); 767: } 768: 769: #define FILE_MNT_WRITE_TAKEN 1 770: #define FILE_MNT_WRITE_RELEASED 2 771: 772: struct file { 773: union { 774: struct llist_node fu_llist; 775: struct rcu_head fu_rcuhead; 776: } f_u; 777: struct path f_path; 778: #define f_dentry f_path.dentry 779: struct inode *f_inode; /* cached value */ 780: const struct file_operations *f_op; 781: 782: /* 783: * Protects f_ep_links, f_flags, f_pos vs i_size in lseek SEEK_CUR. 784: * Must not be taken from IRQ context. 785: */ 786: spinlock_t f_lock; 787: atomic_long_t f_count; 788: unsigned int f_flags; 789: fmode_t f_mode; 790: loff_t f_pos; 791: struct fown_struct f_owner; 792: const struct cred *f_cred; 793: struct file_ra_state f_ra; 794: 795: u64 f_version; 796: #ifdef CONFIG_SECURITY 797: void *f_security; 798: #endif 799: /* needed for tty driver, and maybe others */ 800: void *private_data; 801: 802: #ifdef CONFIG_EPOLL 803: /* Used by fs/eventpoll.c to link all the hooks to this file */ 804: struct list_head f_ep_links; 805: struct list_head f_tfile_llink; 806: #endif /* #ifdef CONFIG_EPOLL */ 807: struct address_space *f_mapping; 808: #ifdef CONFIG_DEBUG_WRITECOUNT 809: unsigned long f_mnt_write_state; 810: #endif 811: }; 812: 813: struct file_handle { 814: __u32 handle_bytes; 815: int handle_type; 816: /* file identifier */ 817: unsigned char f_handle[0]; 818: }; 819: 820: static inline struct file *get_file(struct file *f) 821: { 822: atomic_long_inc(&f->f_count); 823: return f; 824: } 825: #define fput_atomic(x) atomic_long_add_unless(&(x)->f_count, -1, 1) 826: #define file_count(x) atomic_long_read(&(x)->f_count) 827: 828: #ifdef CONFIG_DEBUG_WRITECOUNT 829: static inline void file_take_write(struct file *f) 830: { 831: WARN_ON(f->f_mnt_write_state != 0); 832: f->f_mnt_write_state = FILE_MNT_WRITE_TAKEN; 833: } 834: static inline void file_release_write(struct file *f) 835: { 836: f->f_mnt_write_state |= FILE_MNT_WRITE_RELEASED; 837: } 838: static inline void file_reset_write(struct file *f) 839: { 840: f->f_mnt_write_state = 0; 841: } 842: static inline void file_check_state(struct file *f) 843: { 844: /* 845: * At this point, either both or neither of these bits 846: * should be set. 847: */ 848: WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN); 849: WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_RELEASED); 850: } 851: static inline int file_check_writeable(struct file *f) 852: { 853: if (f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN) 854: return 0; 855: printk(KERN_WARNING "writeable file with no " 856: "mnt_want_write()\n"); 857: WARN_ON(1); 858: return -EINVAL; 859: } 860: #else /* !CONFIG_DEBUG_WRITECOUNT */ 861: static inline void file_take_write(struct file *filp) {} 862: static inline void file_release_write(struct file *filp) {} 863: static inline void file_reset_write(struct file *filp) {} 864: static inline void file_check_state(struct file *filp) {} 865: static inline int file_check_writeable(struct file *filp) 866: { 867: return 0; 868: } 869: #endif /* CONFIG_DEBUG_WRITECOUNT */ 870: 871: #define MAX_NON_LFS ((1UL<<31) - 1) 872: 873: /* Page cache limit. The filesystems should put that into their s_maxbytes 874: limits, otherwise bad things can happen in VM. */ 875: #if BITS_PER_LONG==32 876: #define MAX_LFS_FILESIZE (((loff_t)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1) 877: #elif BITS_PER_LONG==64 878: #define MAX_LFS_FILESIZE ((loff_t)0x7fffffffffffffffLL) 879: #endif 880: 881: #define FL_POSIX 1 882: #define FL_FLOCK 2 883: #define FL_DELEG 4 /* NFSv4 delegation */ 884: #define FL_ACCESS 8 /* not trying to lock, just looking */ 885: #define FL_EXISTS 16 /* when unlocking, test for existence */ 886: #define FL_LEASE 32 /* lease held on this file */ 887: #define FL_CLOSE 64 /* unlock on close */ 888: #define FL_SLEEP 128 /* A blocking lock */ 889: #define FL_DOWNGRADE_PENDING 256 /* Lease is being downgraded */ 890: #define FL_UNLOCK_PENDING 512 /* Lease is being broken */ 891: 892: /* 893: * Special return value from posix_lock_file() and vfs_lock_file() for 894: * asynchronous locking. 895: */ 896: #define FILE_LOCK_DEFERRED 1 897: 898: /* 899: * The POSIX file lock owner is determined by 900: * the "struct files_struct" in the thread group 901: * (or NULL for no owner - BSD locks). 902: * 903: * Lockd stuffs a "host" pointer into this. 904: */ 905: typedef struct files_struct *fl_owner_t; 906: 907: struct file_lock_operations { 908: void (*fl_copy_lock)(struct file_lock *, struct file_lock *); 909: void (*fl_release_private)(struct file_lock *); 910: }; 911: 912: struct lock_manager_operations { 913: int (*lm_compare_owner)(struct file_lock *, struct file_lock *); 914: unsigned long (*lm_owner_key)(struct file_lock *); 915: void (*lm_notify)(struct file_lock *); /* unblock callback */ 916: int (*lm_grant)(struct file_lock *, struct file_lock *, int); 917: void (*lm_break)(struct file_lock *); 918: int (*lm_change)(struct file_lock **, int); 919: }; 920: 921: struct lock_manager { 922: struct list_head list; 923: }; 924: 925: struct net; 926: void locks_start_grace(struct net *, struct lock_manager *); 927: void locks_end_grace(struct lock_manager *); 928: int locks_in_grace(struct net *); 929: 930: /* that will die - we need it for nfs_lock_info */ 931: #include <linux/nfs_fs_i.h> 932: 933: /* 934: * struct file_lock represents a generic "file lock". It's used to represent 935: * POSIX byte range locks, BSD (flock) locks, and leases. It's important to 936: * note that the same struct is used to represent both a request for a lock and 937: * the lock itself, but the same object is never used for both. 938: * 939: * FIXME: should we create a separate "struct lock_request" to help distinguish 940: * these two uses? 941: * 942: * The i_flock list is ordered by: 943: * 944: * 1) lock type -- FL_LEASEs first, then FL_FLOCK, and finally FL_POSIX 945: * 2) lock owner 946: * 3) lock range start 947: * 4) lock range end 948: * 949: * Obviously, the last two criteria only matter for POSIX locks. 950: */ 951: struct file_lock { 952: struct file_lock *fl_next; /* singly linked list for this inode */ 953: struct hlist_node fl_link; /* node in global lists */ 954: struct list_head fl_block; /* circular list of blocked processes */ 955: fl_owner_t fl_owner; 956: unsigned int fl_flags; 957: unsigned char fl_type; 958: unsigned int fl_pid; 959: int fl_link_cpu; /* what cpu's list is this on? */ 960: struct pid *fl_nspid; 961: wait_queue_head_t fl_wait; 962: struct file *fl_file; 963: loff_t fl_start; 964: loff_t fl_end; 965: 966: struct fasync_struct * fl_fasync; /* for lease break notifications */ 967: /* for lease breaks: */ 968: unsigned long fl_break_time; 969: unsigned long fl_downgrade_time; 970: 971: const struct file_lock_operations *fl_ops; /* Callbacks for filesystems */ 972: const struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */ 973: union { 974: struct nfs_lock_info nfs_fl; 975: struct nfs4_lock_info nfs4_fl; 976: struct { 977: struct list_head link; /* link in AFS vnode's pending_locks list */ 978: int state; /* state of grant or error if -ve */ 979: } afs; 980: } fl_u; 981: }; 982: 983: /* The following constant reflects the upper bound of the file/locking space */ 984: #ifndef OFFSET_MAX 985: #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1))) 986: #define OFFSET_MAX INT_LIMIT(loff_t) 987: #define OFFT_OFFSET_MAX INT_LIMIT(off_t) 988: #endif 989: 990: #include <linux/fcntl.h> 991: 992: extern void send_sigio(struct fown_struct *fown, int fd, int band); 993: 994: #ifdef CONFIG_FILE_LOCKING 995: extern int fcntl_getlk(struct file *, struct flock __user *); 996: extern int fcntl_setlk(unsigned int, struct file *, unsigned int, 997: struct flock __user *); 998: 999: #if BITS_PER_LONG == 32 1000: extern int fcntl_getlk64(struct file *, struct flock64 __user *); 1001: extern int fcntl_setlk64(unsigned int, struct file *, unsigned int, 1002: struct flock64 __user *); 1003: #endif 1004: 1005: extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg); 1006: extern int fcntl_getlease(struct file *filp); 1007: 1008: /* fs/locks.c */ 1009: void locks_free_lock(struct file_lock *fl); 1010: extern void locks_init_lock(struct file_lock *); 1011: extern struct file_lock * locks_alloc_lock(void); 1012: extern void locks_copy_lock(struct file_lock *, struct file_lock *); 1013: extern void __locks_copy_lock(struct file_lock *, const struct file_lock *); 1014: extern void locks_remove_posix(struct file *, fl_owner_t); 1015: extern void locks_remove_flock(struct file *); 1016: extern void locks_release_private(struct file_lock *); 1017: extern void posix_test_lock(struct file *, struct file_lock *); 1018: extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *); 1019: extern int posix_lock_file_wait(struct file *, struct file_lock *); 1020: extern int posix_unblock_lock(struct file_lock *); 1021: extern int vfs_test_lock(struct file *, struct file_lock *); 1022: extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *); 1023: extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl); 1024: extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl); 1025: extern int __break_lease(struct inode *inode, unsigned int flags, unsigned int type); 1026: extern void lease_get_mtime(struct inode *, struct timespec *time); 1027: extern int generic_setlease(struct file *, long, struct file_lock **); 1028: extern int vfs_setlease(struct file *, long, struct file_lock **); 1029: extern int lease_modify(struct file_lock **, int); 1030: extern int lock_may_read(struct inode *, loff_t start, unsigned long count); 1031: extern int lock_may_write(struct inode *, loff_t start, unsigned long count); 1032: #else /* !CONFIG_FILE_LOCKING */ 1033: static inline int fcntl_getlk(struct file *file, struct flock __user *user) 1034: { 1035: return -EINVAL; 1036: } 1037: 1038: static inline int fcntl_setlk(unsigned int fd, struct file *file, 1039: unsigned int cmd, struct flock __user *user) 1040: { 1041: return -EACCES; 1042: } 1043: 1044: #if BITS_PER_LONG == 32 1045: static inline int fcntl_getlk64(struct file *file, struct flock64 __user *user) 1046: { 1047: return -EINVAL; 1048: } 1049: 1050: static inline int fcntl_setlk64(unsigned int fd, struct file *file, 1051: unsigned int cmd, struct flock64 __user *user) 1052: { 1053: return -EACCES; 1054: } 1055: #endif 1056: static inline int fcntl_setlease(unsigned int fd, struct file *filp, long arg) 1057: { 1058: return 0; 1059: } 1060: 1061: static inline int fcntl_getlease(struct file *filp) 1062: { 1063: return 0; 1064: } 1065: 1066: static inline void locks_init_lock(struct file_lock *fl) 1067: { 1068: return; 1069: } 1070: 1071: static inline void __locks_copy_lock(struct file_lock *new, struct file_lock *fl) 1072: { 1073: return; 1074: } 1075: 1076: static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl) 1077: { 1078: return; 1079: } 1080: 1081: static inline void locks_remove_posix(struct file *filp, fl_owner_t owner) 1082: { 1083: return; 1084: } 1085: 1086: static inline void locks_remove_flock(struct file *filp) 1087: { 1088: return; 1089: } 1090: 1091: static inline void posix_test_lock(struct file *filp, struct file_lock *fl) 1092: { 1093: return; 1094: } 1095: 1096: static inline int posix_lock_file(struct file *filp, struct file_lock *fl, 1097: struct file_lock *conflock) 1098: { 1099: return -ENOLCK; 1100: } 1101: 1102: static inline int posix_lock_file_wait(struct file *filp, struct file_lock *fl) 1103: { 1104: return -ENOLCK; 1105: } 1106: 1107: static inline int posix_unblock_lock(struct file_lock *waiter) 1108: { 1109: return -ENOENT; 1110: } 1111: 1112: static inline int vfs_test_lock(struct file *filp, struct file_lock *fl) 1113: { 1114: return 0; 1115: } 1116: 1117: static inline int vfs_lock_file(struct file *filp, unsigned int cmd, 1118: struct file_lock *fl, struct file_lock *conf) 1119: { 1120: return -ENOLCK; 1121: } 1122: 1123: static inline int vfs_cancel_lock(struct file *filp, struct file_lock *fl) 1124: { 1125: return 0; 1126: } 1127: 1128: static inline int flock_lock_file_wait(struct file *filp, 1129: struct file_lock *request) 1130: { 1131: return -ENOLCK; 1132: } 1133: 1134: static inline int __break_lease(struct inode *inode, unsigned int mode, unsigned int type) 1135: { 1136: return 0; 1137: } 1138: 1139: static inline void lease_get_mtime(struct inode *inode, struct timespec *time) 1140: { 1141: return; 1142: } 1143: 1144: static inline int generic_setlease(struct file *filp, long arg, 1145: struct file_lock **flp) 1146: { 1147: return -EINVAL; 1148: } 1149: 1150: static inline int vfs_setlease(struct file *filp, long arg, 1151: struct file_lock **lease) 1152: { 1153: return -EINVAL; 1154: } 1155: 1156: static inline int lease_modify(struct file_lock **before, int arg) 1157: { 1158: return -EINVAL; 1159: } 1160: 1161: static inline int lock_may_read(struct inode *inode, loff_t start, 1162: unsigned long len) 1163: { 1164: return 1; 1165: } 1166: 1167: static inline int lock_may_write(struct inode *inode, loff_t start, 1168: unsigned long len) 1169: { 1170: return 1; 1171: } 1172: #endif /* !CONFIG_FILE_LOCKING */ 1173: 1174: 1175: struct fasync_struct { 1176: spinlock_t fa_lock; 1177: int magic; 1178: int fa_fd; 1179: struct fasync_struct *fa_next; /* singly linked list */ 1180: struct file *fa_file; 1181: struct rcu_head fa_rcu; 1182: }; 1183: 1184: #define FASYNC_MAGIC 0x4601 1185: 1186: /* SMP safe fasync helpers: */ 1187: extern int fasync_helper(int, struct file *, int, struct fasync_struct **); 1188: extern struct fasync_struct *fasync_insert_entry(int, struct file *, struct fasync_struct **, struct fasync_struct *); 1189: extern int fasync_remove_entry(struct file *, struct fasync_struct **); 1190: extern struct fasync_struct *fasync_alloc(void); 1191: extern void fasync_free(struct fasync_struct *); 1192: 1193: /* can be called from interrupts */ 1194: extern void kill_fasync(struct fasync_struct **, int, int); 1195: 1196: extern int __f_setown(struct file *filp, struct pid *, enum pid_type, int force); 1197: extern int f_setown(struct file *filp, unsigned long arg, int force); 1198: extern void f_delown(struct file *filp); 1199: extern pid_t f_getown(struct file *filp); 1200: extern int send_sigurg(struct fown_struct *fown); 1201: 1202: struct mm_struct; 1203: 1204: /* 1205: * Umount options 1206: */ 1207: 1208: #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */ 1209: #define MNT_DETACH 0x00000002 /* Just detach from the tree */ 1210: #define MNT_EXPIRE 0x00000004 /* Mark for expiry */ 1211: #define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */ 1212: #define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */ 1213: 1214: extern struct list_head super_blocks; 1215: extern spinlock_t sb_lock; 1216: 1217: /* Possible states of 'frozen' field */ 1218: enum { 1219: SB_UNFROZEN = 0, /* FS is unfrozen */ 1220: SB_FREEZE_WRITE = 1, /* Writes, dir ops, ioctls frozen */ 1221: SB_FREEZE_PAGEFAULT = 2, /* Page faults stopped as well */ 1222: SB_FREEZE_FS = 3, /* For internal FS use (e.g. to stop 1223: * internal threads if needed) */ 1224: SB_FREEZE_COMPLETE = 4, /* ->freeze_fs finished successfully */ 1225: }; 1226: 1227: #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1) 1228: 1229: struct sb_writers { 1230: /* Counters for counting writers at each level */ 1231: struct percpu_counter counter[SB_FREEZE_LEVELS]; 1232: wait_queue_head_t wait; /* queue for waiting for 1233: writers / faults to finish */ 1234: int frozen; /* Is sb frozen? */ 1235: wait_queue_head_t wait_unfrozen; /* queue for waiting for 1236: sb to be thawed */ 1237: #ifdef CONFIG_DEBUG_LOCK_ALLOC 1238: struct lockdep_map lock_map[SB_FREEZE_LEVELS]; 1239: #endif 1240: }; 1241: 1242: struct super_block { 1243: struct list_head s_list; /* Keep this first */ 1244: dev_t s_dev; /* search index; _not_ kdev_t */ 1245: unsigned char s_blocksize_bits; 1246: unsigned long s_blocksize; 1247: loff_t s_maxbytes; /* Max file size */ 1248: struct file_system_type *s_type; 1249: const struct super_operations *s_op; 1250: const struct dquot_operations *dq_op; 1251: const struct quotactl_ops *s_qcop; 1252: const struct export_operations *s_export_op; 1253: unsigned long s_flags; 1254: unsigned long s_magic; 1255: struct dentry *s_root; 1256: struct rw_semaphore s_umount; 1257: int s_count; 1258: atomic_t s_active; 1259: #ifdef CONFIG_SECURITY 1260: void *s_security; 1261: #endif 1262: const struct xattr_handler **s_xattr; 1263: 1264: struct list_head s_inodes; /* all inodes */ 1265: struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */ 1266: struct list_head s_mounts; /* list of mounts; _not_ for fs use */ 1267: struct block_device *s_bdev; 1268: struct backing_dev_info *s_bdi; 1269: struct mtd_info *s_mtd; 1270: struct hlist_node s_instances; 1271: struct quota_info s_dquot; /* Diskquota specific options */ 1272: 1273: struct sb_writers s_writers; 1274: 1275: char s_id[32]; /* Informational name */ 1276: u8 s_uuid[16]; /* UUID */ 1277: 1278: void *s_fs_info; /* Filesystem private info */ 1279: unsigned int s_max_links; 1280: fmode_t s_mode; 1281: 1282: /* Granularity of c/m/atime in ns. 1283: Cannot be worse than a second */ 1284: u32 s_time_gran; 1285: 1286: /* 1287: * The next field is for VFS *only*. No filesystems have any business 1288: * even looking at it. You had been warned. 1289: */ 1290: struct mutex s_vfs_rename_mutex; /* Kludge */ 1291: 1292: /* 1293: * Filesystem subtype. If non-empty the filesystem type field 1294: * in /proc/mounts will be "type.subtype" 1295: */ 1296: char *s_subtype; 1297: 1298: /* 1299: * Saved mount options for lazy filesystems using 1300: * generic_show_options() 1301: */ 1302: char __rcu *s_options; 1303: const struct dentry_operations *s_d_op; /* default d_op for dentries */ 1304: 1305: /* 1306: * Saved pool identifier for cleancache (-1 means none) 1307: */ 1308: int cleancache_poolid; 1309: 1310: struct shrinker s_shrink; /* per-sb shrinker handle */ 1311: 1312: /* Number of inodes with nlink == 0 but still referenced */ 1313: atomic_long_t s_remove_count; 1314: 1315: /* Being remounted read-only */ 1316: int s_readonly_remount; 1317: 1318: /* AIO completions deferred from interrupt context */ 1319: struct workqueue_struct *s_dio_done_wq; 1320: 1321: /* 1322: * Keep the lru lists last in the structure so they always sit on their 1323: * own individual cachelines. 1324: */ 1325: struct list_lru s_dentry_lru ____cacheline_aligned_in_smp; 1326: struct list_lru s_inode_lru ____cacheline_aligned_in_smp; 1327: struct rcu_head rcu; 1328: }; 1329: 1330: extern struct timespec current_fs_time(struct super_block *sb); 1331: 1332: /* 1333: * Snapshotting support. 1334: */ 1335: 1336: void __sb_end_write(struct super_block *sb, int level); 1337: int __sb_start_write(struct super_block *sb, int level, bool wait); 1338: 1339: /** 1340: * sb_end_write - drop write access to a superblock 1341: * @sb: the super we wrote to 1342: * 1343: * Decrement number of writers to the filesystem. Wake up possible waiters 1344: * wanting to freeze the filesystem. 1345: */ 1346: static inline void sb_end_write(struct super_block *sb) 1347: { 1348: __sb_end_write(sb, SB_FREEZE_WRITE); 1349: } 1350: 1351: /** 1352: * sb_end_pagefault - drop write access to a superblock from a page fault 1353: * @sb: the super we wrote to 1354: * 1355: * Decrement number of processes handling write page fault to the filesystem. 1356: * Wake up possible waiters wanting to freeze the filesystem. 1357: */ 1358: static inline void sb_end_pagefault(struct super_block *sb) 1359: { 1360: __sb_end_write(sb, SB_FREEZE_PAGEFAULT); 1361: } 1362: 1363: /** 1364: * sb_end_intwrite - drop write access to a superblock for internal fs purposes 1365: * @sb: the super we wrote to 1366: * 1367: * Decrement fs-internal number of writers to the filesystem. Wake up possible 1368: * waiters wanting to freeze the filesystem. 1369: */ 1370: static inline void sb_end_intwrite(struct super_block *sb) 1371: { 1372: __sb_end_write(sb, SB_FREEZE_FS); 1373: } 1374: 1375: /** 1376: * sb_start_write - get write access to a superblock 1377: * @sb: the super we write to 1378: * 1379: * When a process wants to write data or metadata to a file system (i.e. dirty 1380: * a page or an inode), it should embed the operation in a sb_start_write() - 1381: * sb_end_write() pair to get exclusion against file system freezing. This 1382: * function increments number of writers preventing freezing. If the file 1383: * system is already frozen, the function waits until the file system is 1384: * thawed. 1385: * 1386: * Since freeze protection behaves as a lock, users have to preserve 1387: * ordering of freeze protection and other filesystem locks. Generally, 1388: * freeze protection should be the outermost lock. In particular, we have: 1389: * 1390: * sb_start_write 1391: * -> i_mutex (write path, truncate, directory ops, ...) 1392: * -> s_umount (freeze_super, thaw_super) 1393: */ 1394: static inline void sb_start_write(struct super_block *sb) 1395: { 1396: __sb_start_write(sb, SB_FREEZE_WRITE, true); 1397: } 1398: 1399: static inline int sb_start_write_trylock(struct super_block *sb) 1400: { 1401: return __sb_start_write(sb, SB_FREEZE_WRITE, false); 1402: } 1403: 1404: /** 1405: * sb_start_pagefault - get write access to a superblock from a page fault 1406: * @sb: the super we write to 1407: * 1408: * When a process starts handling write page fault, it should embed the 1409: * operation into sb_start_pagefault() - sb_end_pagefault() pair to get 1410: * exclusion against file system freezing. This is needed since the page fault 1411: * is going to dirty a page. This function increments number of running page 1412: * faults preventing freezing. If the file system is already frozen, the 1413: * function waits until the file system is thawed. 1414: * 1415: * Since page fault freeze protection behaves as a lock, users have to preserve 1416: * ordering of freeze protection and other filesystem locks. It is advised to 1417: * put sb_start_pagefault() close to mmap_sem in lock ordering. Page fault 1418: * handling code implies lock dependency: 1419: * 1420: * mmap_sem 1421: * -> sb_start_pagefault 1422: */ 1423: static inline void sb_start_pagefault(struct super_block *sb) 1424: { 1425: __sb_start_write(sb, SB_FREEZE_PAGEFAULT, true); 1426: } 1427: 1428: /* 1429: * sb_start_intwrite - get write access to a superblock for internal fs purposes 1430: * @sb: the super we write to 1431: * 1432: * This is the third level of protection against filesystem freezing. It is 1433: * free for use by a filesystem. The only requirement is that it must rank 1434: * below sb_start_pagefault. 1435: * 1436: * For example filesystem can call sb_start_intwrite() when starting a 1437: * transaction which somewhat eases handling of freezing for internal sources 1438: * of filesystem changes (internal fs threads, discarding preallocation on file 1439: * close, etc.). 1440: */ 1441: static inline void sb_start_intwrite(struct super_block *sb) 1442: { 1443: __sb_start_write(sb, SB_FREEZE_FS, true); 1444: } 1445: 1446: 1447: extern bool inode_owner_or_capable(const struct inode *inode); 1448: 1449: /* 1450: * VFS helper functions.. 1451: */ 1452: extern int vfs_create(struct inode *, struct dentry *, umode_t, bool); 1453: extern int vfs_mkdir(struct inode *, struct dentry *, umode_t); 1454: extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t); 1455: extern int vfs_symlink(struct inode *, struct dentry *, const char *); 1456: extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **); 1457: extern int vfs_rmdir(struct inode *, struct dentry *); 1458: extern int vfs_unlink(struct inode *, struct dentry *, struct inode **); 1459: extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **); 1460: 1461: /* 1462: * VFS dentry helper functions. 1463: */ 1464: extern void dentry_unhash(struct dentry *dentry); 1465: 1466: /* 1467: * VFS file helper functions. 1468: */ 1469: extern void inode_init_owner(struct inode *inode, const struct inode *dir, 1470: umode_t mode); 1471: /* 1472: * VFS FS_IOC_FIEMAP helper definitions. 1473: */ 1474: struct fiemap_extent_info { 1475: unsigned int fi_flags; /* Flags as passed from user */ 1476: unsigned int fi_extents_mapped; /* Number of mapped extents */ 1477: unsigned int fi_extents_max; /* Size of fiemap_extent array */ 1478: struct fiemap_extent __user *fi_extents_start; /* Start of 1479: fiemap_extent array */ 1480: }; 1481: int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical, 1482: u64 phys, u64 len, u32 flags); 1483: int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags); 1484: 1485: /* 1486: * File types 1487: * 1488: * NOTE! These match bits 12..15 of stat.st_mode 1489: * (ie "(i_mode >> 12) & 15"). 1490: */ 1491: #define DT_UNKNOWN 0 1492: #define DT_FIFO 1 1493: #define DT_CHR 2 1494: #define DT_DIR 4 1495: #define DT_BLK 6 1496: #define DT_REG 8 1497: #define DT_LNK 10 1498: #define DT_SOCK 12 1499: #define DT_WHT 14 1500: 1501: /* 1502: * This is the "filldir" function type, used by readdir() to let 1503: * the kernel specify what kind of dirent layout it wants to have. 1504: * This allows the kernel to read directories into kernel space or 1505: * to have different dirent layouts depending on the binary type. 1506: */ 1507: typedef int (*filldir_t)(void *, const char *, int, loff_t, u64, unsigned); 1508: struct dir_context { 1509: const filldir_t actor; 1510: loff_t pos; 1511: }; 1512: 1513: struct block_device_operations; 1514: 1515: /* These macros are for out of kernel modules to test that 1516: * the kernel supports the unlocked_ioctl and compat_ioctl 1517: * fields in struct file_operations. */ 1518: #define HAVE_COMPAT_IOCTL 1 1519: #define HAVE_UNLOCKED_IOCTL 1 1520: 1521: struct file_operations { 1522: struct module *owner; 1523: loff_t (*llseek) (struct file *, loff_t, int); 1524: ssize_t (*read) (struct file *, char __user *, size_t, loff_t *); 1525: ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *); 1526: ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t); 1527: ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t); 1528: int (*iterate) (struct file *, struct dir_context *); 1529: unsigned int (*poll) (struct file *, struct poll_table_struct *); 1530: long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); 1531: long (*compat_ioctl) (struct file *, unsigned int, unsigned long); 1532: int (*mmap) (struct file *, struct vm_area_struct *); 1533: int (*open) (struct inode *, struct file *); 1534: int (*flush) (struct file *, fl_owner_t id); 1535: int (*release) (struct inode *, struct file *); 1536: int (*fsync) (struct file *, loff_t, loff_t, int datasync); 1537: int (*aio_fsync) (struct kiocb *, int datasync); 1538: int (*fasync) (int, struct file *, int); 1539: int (*lock) (struct file *, int, struct file_lock *); 1540: ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int); 1541: unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); 1542: int (*check_flags)(int); 1543: int (*flock) (struct file *, int, struct file_lock *); 1544: ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int); 1545: ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int); 1546: int (*setlease)(struct file *, long, struct file_lock **); 1547: long (*fallocate)(struct file *file, int mode, loff_t offset, 1548: loff_t len); 1549: int (*show_fdinfo)(struct seq_file *m, struct file *f); 1550: }; 1551: 1552: struct inode_operations { 1553: struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int); 1554: void * (*follow_link) (struct dentry *, struct nameidata *); 1555: int (*permission) (struct inode *, int); 1556: struct posix_acl * (*get_acl)(struct inode *, int); 1557: 1558: int (*readlink) (struct dentry *, char __user *,int); 1559: void (*put_link) (struct dentry *, struct nameidata *, void *); 1560: 1561: int (*create) (struct inode *,struct dentry *, umode_t, bool); 1562: int (*link) (struct dentry *,struct inode *,struct dentry *); 1563: int (*unlink) (struct inode *,struct dentry *); 1564: int (*symlink) (struct inode *,struct dentry *,const char *); 1565: int (*mkdir) (struct inode *,struct dentry *,umode_t); 1566: int (*rmdir) (struct inode *,struct dentry *); 1567: int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t); 1568: int (*rename) (struct inode *, struct dentry *, 1569: struct inode *, struct dentry *); 1570: int (*setattr) (struct dentry *, struct iattr *); 1571: int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *); 1572: int (*setxattr) (struct dentry *, const char *,const void *,size_t,int); 1573: ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t); 1574: ssize_t (*listxattr) (struct dentry *, char *, size_t); 1575: int (*removexattr) (struct dentry *, const char *); 1576: int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, 1577: u64 len); 1578: int (*update_time)(struct inode *, struct timespec *, int); 1579: int (*atomic_open)(struct inode *, struct dentry *, 1580: struct file *, unsigned open_flag, 1581: umode_t create_mode, int *opened); 1582: int (*tmpfile) (struct inode *, struct dentry *, umode_t); 1583: } ____cacheline_aligned; 1584: 1585: ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, 1586: unsigned long nr_segs, unsigned long fast_segs, 1587: struct iovec *fast_pointer, 1588: struct iovec **ret_pointer); 1589: 1590: extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *); 1591: extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *); 1592: extern ssize_t vfs_readv(struct file *, const struct iovec __user *, 1593: unsigned long, loff_t *); 1594: extern ssize_t vfs_writev(struct file *, const struct iovec __user *, 1595: unsigned long, loff_t *); 1596: 1597: struct super_operations { 1598: struct inode *(*alloc_inode)(struct super_block *sb); 1599: void (*destroy_inode)(struct inode *); 1600: 1601: void (*dirty_inode) (struct inode *, int flags); 1602: int (*write_inode) (struct inode *, struct writeback_control *wbc); 1603: int (*drop_inode) (struct inode *); 1604: void (*evict_inode) (struct inode *); 1605: void (*put_super) (struct super_block *); 1606: int (*sync_fs)(struct super_block *sb, int wait); 1607: int (*freeze_fs) (struct super_block *); 1608: int (*unfreeze_fs) (struct super_block *); 1609: int (*statfs) (struct dentry *, struct kstatfs *); 1610: int (*remount_fs) (struct super_block *, int *, char *); 1611: void (*umount_begin) (struct super_block *); 1612: 1613: int (*show_options)(struct seq_file *, struct dentry *); 1614: int (*show_devname)(struct seq_file *, struct dentry *); 1615: int (*show_path)(struct seq_file *, struct dentry *); 1616: int (*show_stats)(struct seq_file *, struct dentry *); 1617: #ifdef CONFIG_QUOTA 1618: ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t); 1619: ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t); 1620: #endif 1621: int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t); 1622: long (*nr_cached_objects)(struct super_block *, int); 1623: long (*free_cached_objects)(struct super_block *, long, int); 1624: }; 1625: 1626: /* 1627: * Inode flags - they have no relation to superblock flags now 1628: */ 1629: #define S_SYNC 1 /* Writes are synced at once */ 1630: #define S_NOATIME 2 /* Do not update access times */ 1631: #define S_APPEND 4 /* Append-only file */ 1632: #define S_IMMUTABLE 8 /* Immutable file */ 1633: #define S_DEAD 16 /* removed, but still open directory */ 1634: #define S_NOQUOTA 32 /* Inode is not counted to quota */ 1635: #define S_DIRSYNC 64 /* Directory modifications are synchronous */ 1636: #define S_NOCMTIME 128 /* Do not update file c/mtime */ 1637: #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */ 1638: #define S_PRIVATE 512 /* Inode is fs-internal */ 1639: #define S_IMA 1024 /* Inode has an associated IMA struct */ 1640: #define S_AUTOMOUNT 2048 /* Automount/referral quasi-directory */ 1641: #define S_NOSEC 4096 /* no suid or xattr security attributes */ 1642: 1643: /* 1644: * Note that nosuid etc flags are inode-specific: setting some file-system 1645: * flags just means all the inodes inherit those flags by default. It might be 1646: * possible to override it selectively if you really wanted to with some 1647: * ioctl() that is not currently implemented. 1648: * 1649: * Exception: MS_RDONLY is always applied to the entire file system. 1650: * 1651: * Unfortunately, it is possible to change a filesystems flags with it mounted 1652: * with files in use. This means that all of the inodes will not have their 1653: * i_flags updated. Hence, i_flags no longer inherit the superblock mount 1654: * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org 1655: */ 1656: #define __IS_FLG(inode, flg) ((inode)->i_sb->s_flags & (flg)) 1657: 1658: #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY) 1659: #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \ 1660: ((inode)->i_flags & S_SYNC)) 1661: #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \ 1662: ((inode)->i_flags & (S_SYNC|S_DIRSYNC))) 1663: #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK) 1664: #define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME) 1665: #define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION) 1666: 1667: #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA) 1668: #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND) 1669: #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE) 1670: #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL) 1671: 1672: #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD) 1673: #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME) 1674: #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE) 1675: #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE) 1676: #define IS_IMA(inode) ((inode)->i_flags & S_IMA) 1677: #define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT) 1678: #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC) 1679: 1680: /* 1681: * Inode state bits. Protected by inode->i_lock 1682: * 1683: * Three bits determine the dirty state of the inode, I_DIRTY_SYNC, 1684: * I_DIRTY_DATASYNC and I_DIRTY_PAGES. 1685: * 1686: * Four bits define the lifetime of an inode. Initially, inodes are I_NEW, 1687: * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at 1688: * various stages of removing an inode. 1689: * 1690: * Two bits are used for locking and completion notification, I_NEW and I_SYNC. 1691: * 1692: * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on 1693: * fdatasync(). i_atime is the usual cause. 1694: * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of 1695: * these changes separately from I_DIRTY_SYNC so that we 1696: * don't have to write inode on fdatasync() when only 1697: * mtime has changed in it. 1698: * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean. 1699: * I_NEW Serves as both a mutex and completion notification. 1700: * New inodes set I_NEW. If two processes both create 1701: * the same inode, one of them will release its inode and 1702: * wait for I_NEW to be released before returning. 1703: * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can 1704: * also cause waiting on I_NEW, without I_NEW actually 1705: * being set. find_inode() uses this to prevent returning 1706: * nearly-dead inodes. 1707: * I_WILL_FREE Must be set when calling write_inode_now() if i_count 1708: * is zero. I_FREEING must be set when I_WILL_FREE is 1709: * cleared. 1710: * I_FREEING Set when inode is about to be freed but still has dirty 1711: * pages or buffers attached or the inode itself is still 1712: * dirty. 1713: * I_CLEAR Added by clear_inode(). In this state the inode is 1714: * clean and can be destroyed. Inode keeps I_FREEING. 1715: * 1716: * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are 1717: * prohibited for many purposes. iget() must wait for 1718: * the inode to be completely released, then create it 1719: * anew. Other functions will just ignore such inodes, 1720: * if appropriate. I_NEW is used for waiting. 1721: * 1722: * I_SYNC Writeback of inode is running. The bit is set during 1723: * data writeback, and cleared with a wakeup on the bit 1724: * address once it is done. The bit is also used to pin 1725: * the inode in memory for flusher thread. 1726: * 1727: * I_REFERENCED Marks the inode as recently references on the LRU list. 1728: * 1729: * I_DIO_WAKEUP Never set. Only used as a key for wait_on_bit(). 1730: * 1731: * Q: What is the difference between I_WILL_FREE and I_FREEING? 1732: */ 1733: #define I_DIRTY_SYNC (1 << 0) 1734: #define I_DIRTY_DATASYNC (1 << 1) 1735: #define I_DIRTY_PAGES (1 << 2) 1736: #define __I_NEW 3 1737: #define I_NEW (1 << __I_NEW) 1738: #define I_WILL_FREE (1 << 4) 1739: #define I_FREEING (1 << 5) 1740: #define I_CLEAR (1 << 6) 1741: #define __I_SYNC 7 1742: #define I_SYNC (1 << __I_SYNC) 1743: #define I_REFERENCED (1 << 8) 1744: #define __I_DIO_WAKEUP 9 1745: #define I_DIO_WAKEUP (1 << I_DIO_WAKEUP) 1746: #define I_LINKABLE (1 << 10) 1747: 1748: #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES) 1749: 1750: extern void __mark_inode_dirty(struct inode *, int); 1751: static inline void mark_inode_dirty(struct inode *inode) 1752: { 1753: __mark_inode_dirty(inode, I_DIRTY); 1754: } 1755: 1756: static inline void mark_inode_dirty_sync(struct inode *inode) 1757: { 1758: __mark_inode_dirty(inode, I_DIRTY_SYNC); 1759: } 1760: 1761: extern void inc_nlink(struct inode *inode); 1762: extern void drop_nlink(struct inode *inode); 1763: extern void clear_nlink(struct inode *inode); 1764: extern void set_nlink(struct inode *inode, unsigned int nlink); 1765: 1766: static inline void inode_inc_link_count(struct inode *inode) 1767: { 1768: inc_nlink(inode); 1769: mark_inode_dirty(inode); 1770: } 1771: 1772: static inline void inode_dec_link_count(struct inode *inode) 1773: { 1774: drop_nlink(inode); 1775: mark_inode_dirty(inode); 1776: } 1777: 1778: /** 1779: * inode_inc_iversion - increments i_version 1780: * @inode: inode that need to be updated 1781: * 1782: * Every time the inode is modified, the i_version field will be incremented. 1783: * The filesystem has to be mounted with i_version flag 1784: */ 1785: 1786: static inline void inode_inc_iversion(struct inode *inode) 1787: { 1788: spin_lock(&inode->i_lock); 1789: inode->i_version++; 1790: spin_unlock(&inode->i_lock); 1791: } 1792: 1793: enum file_time_flags { 1794: S_ATIME = 1, 1795: S_MTIME = 2, 1796: S_CTIME = 4, 1797: S_VERSION = 8, 1798: }; 1799: 1800: extern void touch_atime(const struct path *); 1801: static inline void file_accessed(struct file *file) 1802: { 1803: if (!(file->f_flags & O_NOATIME)) 1804: touch_atime(&file->f_path); 1805: } 1806: 1807: int sync_inode(struct inode *inode, struct writeback_control *wbc); 1808: int sync_inode_metadata(struct inode *inode, int wait); 1809: 1810: struct file_system_type { 1811: const char *name; 1812: int fs_flags; 1813: #define FS_REQUIRES_DEV 1 1814: #define FS_BINARY_MOUNTDATA 2 1815: #define FS_HAS_SUBTYPE 4 1816: #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */ 1817: #define FS_USERNS_DEV_MOUNT 16 /* A userns mount does not imply MNT_NODEV */ 1818: #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */ 1819: struct dentry *(*mount) (struct file_system_type *, int, 1820: const char *, void *); 1821: void (*kill_sb) (struct super_block *); 1822: struct module *owner; 1823: struct file_system_type * next; 1824: struct hlist_head fs_supers; 1825: 1826: struct lock_class_key s_lock_key; 1827: struct lock_class_key s_umount_key; 1828: struct lock_class_key s_vfs_rename_key; 1829: struct lock_class_key s_writers_key[SB_FREEZE_LEVELS]; 1830: 1831: struct lock_class_key i_lock_key; 1832: struct lock_class_key i_mutex_key; 1833: struct lock_class_key i_mutex_dir_key; 1834: }; 1835: 1836: #define MODULE_ALIAS_FS(NAME) MODULE_ALIAS("fs-" NAME) 1837: 1838: extern struct dentry *mount_ns(struct file_system_type *fs_type, int flags, 1839: void *data, int (*fill_super)(struct super_block *, void *, int)); 1840: extern struct dentry *mount_bdev(struct file_system_type *fs_type, 1841: int flags, const char *dev_name, void *data, 1842: int (*fill_super)(struct super_block *, void *, int)); 1843: extern struct dentry *mount_single(struct file_system_type *fs_type, 1844: int flags, void *data, 1845: int (*fill_super)(struct super_block *, void *, int)); 1846: extern struct dentry *mount_nodev(struct file_system_type *fs_type, 1847: int flags, void *data, 1848: int (*fill_super)(struct super_block *, void *, int)); 1849: extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path); 1850: void generic_shutdown_super(struct super_block *sb); 1851: void kill_block_super(struct super_block *sb); 1852: void kill_anon_super(struct super_block *sb); 1853: void kill_litter_super(struct super_block *sb); 1854: void deactivate_super(struct super_block *sb); 1855: void deactivate_locked_super(struct super_block *sb); 1856: int set_anon_super(struct super_block *s, void *data); 1857: int get_anon_bdev(dev_t *); 1858: void free_anon_bdev(dev_t); 1859: struct super_block *sget(struct file_system_type *type, 1860: int (*test)(struct super_block *,void *), 1861: int (*set)(struct super_block *,void *), 1862: int flags, void *data); 1863: extern struct dentry *mount_pseudo(struct file_system_type *, char *, 1864: const struct super_operations *ops, 1865: const struct dentry_operations *dops, 1866: unsigned long); 1867: 1868: /* Alas, no aliases. Too much hassle with bringing module.h everywhere */ 1869: #define fops_get(fops) \ 1870: (((fops) && try_module_get((fops)->owner) ? (fops) : NULL)) 1871: #define fops_put(fops) \ 1872: do { if (fops) module_put((fops)->owner); } while(0) 1873: /* 1874: * This one is to be used *ONLY* from ->open() instances. 1875: * fops must be non-NULL, pinned down *and* module dependencies 1876: * should be sufficient to pin the caller down as well. 1877: */ 1878: #define replace_fops(f, fops) \ 1879: do { \ 1880: struct file *__file = (f); \ 1881: fops_put(__file->f_op); \ 1882: BUG_ON(!(__file->f_op = (fops))); \ 1883: } while(0) 1884: 1885: extern int register_filesystem(struct file_system_type *); 1886: extern int unregister_filesystem(struct file_system_type *); 1887: extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data); 1888: #define kern_mount(type) kern_mount_data(type, NULL) 1889: extern void kern_unmount(struct vfsmount *mnt); 1890: extern int may_umount_tree(struct vfsmount *); 1891: extern int may_umount(struct vfsmount *); 1892: extern long do_mount(const char *, const char *, const char *, unsigned long, void *); 1893: extern struct vfsmount *collect_mounts(struct path *); 1894: extern void drop_collected_mounts(struct vfsmount *); 1895: extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *, 1896: struct vfsmount *); 1897: extern int vfs_statfs(struct path *, struct kstatfs *); 1898: extern int user_statfs(const char __user *, struct kstatfs *); 1899: extern int fd_statfs(int, struct kstatfs *); 1900: extern int vfs_ustat(dev_t, struct kstatfs *); 1901: extern int freeze_super(struct super_block *super); 1902: extern int thaw_super(struct super_block *super); 1903: extern bool our_mnt(struct vfsmount *mnt); 1904: extern bool fs_fully_visible(struct file_system_type *); 1905: 1906: extern int current_umask(void); 1907: 1908: extern void ihold(struct inode * inode); 1909: extern void iput(struct inode *); 1910: 1911: /* /sys/fs */ 1912: extern struct kobject *fs_kobj; 1913: 1914: #define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK) 1915: 1916: #define FLOCK_VERIFY_READ 1 1917: #define FLOCK_VERIFY_WRITE 2 1918: 1919: #ifdef CONFIG_FILE_LOCKING 1920: extern int locks_mandatory_locked(struct inode *); 1921: extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t); 1922: 1923: /* 1924: * Candidates for mandatory locking have the setgid bit set 1925: * but no group execute bit - an otherwise meaningless combination. 1926: */ 1927: 1928: static inline int __mandatory_lock(struct inode *ino) 1929: { 1930: return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID; 1931: } 1932: 1933: /* 1934: * ... and these candidates should be on MS_MANDLOCK mounted fs, 1935: * otherwise these will be advisory locks 1936: */ 1937: 1938: static inline int mandatory_lock(struct inode *ino) 1939: { 1940: return IS_MANDLOCK(ino) && __mandatory_lock(ino); 1941: } 1942: 1943: static inline int locks_verify_locked(struct inode *inode) 1944: { 1945: if (mandatory_lock(inode)) 1946: return locks_mandatory_locked(inode); 1947: return 0; 1948: } 1949: 1950: static inline int locks_verify_truncate(struct inode *inode, 1951: struct file *filp, 1952: loff_t size) 1953: { 1954: if (inode->i_flock && mandatory_lock(inode)) 1955: return locks_mandatory_area( 1956: FLOCK_VERIFY_WRITE, inode, filp, 1957: size < inode->i_size ? size : inode->i_size, 1958: (size < inode->i_size ? inode->i_size - size 1959: : size - inode->i_size) 1960: ); 1961: return 0; 1962: } 1963: 1964: static inline int break_lease(struct inode *inode, unsigned int mode) 1965: { 1966: if (inode->i_flock) 1967: return __break_lease(inode, mode, FL_LEASE); 1968: return 0; 1969: } 1970: 1971: static inline int break_deleg(struct inode *inode, unsigned int mode) 1972: { 1973: if (inode->i_flock) 1974: return __break_lease(inode, mode, FL_DELEG); 1975: return 0; 1976: } 1977: 1978: static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode) 1979: { 1980: int ret; 1981: 1982: ret = break_deleg(inode, O_WRONLY|O_NONBLOCK); 1983: if (ret == -EWOULDBLOCK && delegated_inode) { 1984: *delegated_inode = inode; 1985: ihold(inode); 1986: } 1987: return ret; 1988: } 1989: 1990: static inline int break_deleg_wait(struct inode **delegated_inode) 1991: { 1992: int ret; 1993: 1994: ret = break_deleg(*delegated_inode, O_WRONLY); 1995: iput(*delegated_inode); 1996: *delegated_inode = NULL; 1997: return ret; 1998: } 1999: 2000: #else /* !CONFIG_FILE_LOCKING */ 2001: static inline int locks_mandatory_locked(struct inode *inode) 2002: { 2003: return 0; 2004: } 2005: 2006: static inline int locks_mandatory_area(int rw, struct inode *inode, 2007: struct file *filp, loff_t offset, 2008: size_t count) 2009: { 2010: return 0; 2011: } 2012: 2013: static inline int __mandatory_lock(struct inode *inode) 2014: { 2015: return 0; 2016: } 2017: 2018: static inline int mandatory_lock(struct inode *inode) 2019: { 2020: return 0; 2021: } 2022: 2023: static inline int locks_verify_locked(struct inode *inode) 2024: { 2025: return 0; 2026: } 2027: 2028: static inline int locks_verify_truncate(struct inode *inode, struct file *filp, 2029: size_t size) 2030: { 2031: return 0; 2032: } 2033: 2034: static inline int break_lease(struct inode *inode, unsigned int mode) 2035: { 2036: return 0; 2037: } 2038: 2039: static inline int break_deleg(struct inode *inode, unsigned int mode) 2040: { 2041: return 0; 2042: } 2043: 2044: static inline int try_break_deleg(struct inode *inode, struct inode **delegated_inode) 2045: { 2046: return 0; 2047: } 2048: 2049: static inline int break_deleg_wait(struct inode **delegated_inode) 2050: { 2051: BUG(); 2052: return 0; 2053: } 2054: 2055: #endif /* CONFIG_FILE_LOCKING */ 2056: 2057: /* fs/open.c */ 2058: struct audit_names; 2059: struct filename { 2060: const char *name; /* pointer to actual string */ 2061: const __user char *uptr; /* original userland pointer */ 2062: struct audit_names *aname; 2063: bool separate; /* should "name" be freed? */ 2064: }; 2065: 2066: extern long vfs_truncate(struct path *, loff_t); 2067: extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs, 2068: struct file *filp); 2069: extern int do_fallocate(struct file *file, int mode, loff_t offset, 2070: loff_t len); 2071: extern long do_sys_open(int dfd, const char __user *filename, int flags, 2072: umode_t mode); 2073: extern struct file *file_open_name(struct filename *, int, umode_t); 2074: extern struct file *filp_open(const char *, int, umode_t); 2075: extern struct file *file_open_root(struct dentry *, struct vfsmount *, 2076: const char *, int); 2077: extern struct file * dentry_open(const struct path *, int, const struct cred *); 2078: extern int filp_close(struct file *, fl_owner_t id); 2079: 2080: extern struct filename *getname(const char __user *); 2081: 2082: enum { 2083: FILE_CREATED = 1, 2084: FILE_OPENED = 2 2085: }; 2086: extern int finish_open(struct file *file, struct dentry *dentry, 2087: int (*open)(struct inode *, struct file *), 2088: int *opened); 2089: extern int finish_no_open(struct file *file, struct dentry *dentry); 2090: 2091: /* fs/ioctl.c */ 2092: 2093: extern int ioctl_preallocate(struct file *filp, void __user *argp); 2094: 2095: /* fs/dcache.c */ 2096: extern void __init vfs_caches_init_early(void); 2097: extern void __init vfs_caches_init(unsigned long); 2098: 2099: extern struct kmem_cache *names_cachep; 2100: 2101: extern void final_putname(struct filename *name); 2102: 2103: #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL) 2104: #define __putname(name) kmem_cache_free(names_cachep, (void *)(name)) 2105: #ifndef CONFIG_AUDITSYSCALL 2106: #define putname(name) final_putname(name) 2107: #else 2108: extern void putname(struct filename *name); 2109: #endif 2110: 2111: #ifdef CONFIG_BLOCK 2112: extern int register_blkdev(unsigned int, const char *); 2113: extern void unregister_blkdev(unsigned int, const char *); 2114: extern struct block_device *bdget(dev_t); 2115: extern struct block_device *bdgrab(struct block_device *bdev); 2116: extern void bd_set_size(struct block_device *, loff_t size); 2117: extern void bd_forget(struct inode *inode); 2118: extern void bdput(struct block_device *); 2119: extern void invalidate_bdev(struct block_device *); 2120: extern void iterate_bdevs(void (*)(struct block_device *, void *), void *); 2121: extern int sync_blockdev(struct block_device *bdev); 2122: extern void kill_bdev(struct block_device *); 2123: extern struct super_block *freeze_bdev(struct block_device *); 2124: extern void emergency_thaw_all(void); 2125: extern int thaw_bdev(struct block_device *bdev, struct super_block *sb); 2126: extern int fsync_bdev(struct block_device *); 2127: extern int sb_is_blkdev_sb(struct super_block *sb); 2128: #else 2129: static inline void bd_forget(struct inode *inode) {} 2130: static inline int sync_blockdev(struct block_device *bdev) { return 0; } 2131: static inline void kill_bdev(struct block_device *bdev) {} 2132: static inline void invalidate_bdev(struct block_device *bdev) {} 2133: 2134: static inline struct super_block *freeze_bdev(struct block_device *sb) 2135: { 2136: return NULL; 2137: } 2138: 2139: static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb) 2140: { 2141: return 0; 2142: } 2143: 2144: static inline void iterate_bdevs(void (*f)(struct block_device *, void *), void *arg) 2145: { 2146: } 2147: 2148: static inline int sb_is_blkdev_sb(struct super_block *sb) 2149: { 2150: return 0; 2151: } 2152: #endif 2153: extern int sync_filesystem(struct super_block *); 2154: extern const struct file_operations def_blk_fops; 2155: extern const struct file_operations def_chr_fops; 2156: extern const struct file_operations bad_sock_fops; 2157: #ifdef CONFIG_BLOCK 2158: extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long); 2159: extern int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long); 2160: extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long); 2161: extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder); 2162: extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode, 2163: void *holder); 2164: extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode, 2165: void *holder); 2166: extern void blkdev_put(struct block_device *bdev, fmode_t mode); 2167: #ifdef CONFIG_SYSFS 2168: extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk); 2169: extern void bd_unlink_disk_holder(struct block_device *bdev, 2170: struct gendisk *disk); 2171: #else 2172: static inline int bd_link_disk_holder(struct block_device *bdev, 2173: struct gendisk *disk) 2174: { 2175: return 0; 2176: } 2177: static inline void bd_unlink_disk_holder(struct block_device *bdev, 2178: struct gendisk *disk) 2179: { 2180: } 2181: #endif 2182: #endif 2183: 2184: /* fs/char_dev.c */ 2185: #define CHRDEV_MAJOR_HASH_SIZE 255 2186: extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *); 2187: extern int register_chrdev_region(dev_t, unsigned, const char *); 2188: extern int __register_chrdev(unsigned int major, unsigned int baseminor, 2189: unsigned int count, const char *name, 2190: const struct file_operations *fops); 2191: extern void __unregister_chrdev(unsigned int major, unsigned int baseminor, 2192: unsigned int count, const char *name); 2193: extern void unregister_chrdev_region(dev_t, unsigned); 2194: extern void chrdev_show(struct seq_file *,off_t); 2195: 2196: static inline int register_chrdev(unsigned int major, const char *name, 2197: const struct file_operations *fops) 2198: { 2199: return __register_chrdev(major, 0, 256, name, fops); 2200: } 2201: 2202: static inline void unregister_chrdev(unsigned int major, const char *name) 2203: { 2204: __unregister_chrdev(major, 0, 256, name); 2205: } 2206: 2207: /* fs/block_dev.c */ 2208: #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */ 2209: #define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */ 2210: 2211: #ifdef CONFIG_BLOCK 2212: #define BLKDEV_MAJOR_HASH_SIZE 255 2213: extern const char *__bdevname(dev_t, char *buffer); 2214: extern const char *bdevname(struct block_device *bdev, char *buffer); 2215: extern struct block_device *lookup_bdev(const char *); 2216: extern void blkdev_show(struct seq_file *,off_t); 2217: 2218: #else 2219: #define BLKDEV_MAJOR_HASH_SIZE 0 2220: #endif 2221: 2222: extern void init_special_inode(struct inode *, umode_t, dev_t); 2223: 2224: /* Invalid inode operations -- fs/bad_inode.c */ 2225: extern void make_bad_inode(struct inode *); 2226: extern int is_bad_inode(struct inode *); 2227: 2228: #ifdef CONFIG_BLOCK 2229: /* 2230: * return READ, READA, or WRITE 2231: */ 2232: #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK)) 2233: 2234: /* 2235: * return data direction, READ or WRITE 2236: */ 2237: #define bio_data_dir(bio) ((bio)->bi_rw & 1) 2238: 2239: extern void check_disk_size_change(struct gendisk *disk, 2240: struct block_device *bdev); 2241: extern int revalidate_disk(struct gendisk *); 2242: extern int check_disk_change(struct block_device *); 2243: extern int __invalidate_device(struct block_device *, bool); 2244: extern int invalidate_partition(struct gendisk *, int); 2245: #endif 2246: unsigned long invalidate_mapping_pages(struct address_space *mapping, 2247: pgoff_t start, pgoff_t end); 2248: 2249: static inline void invalidate_remote_inode(struct inode *inode) 2250: { 2251: if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 2252: S_ISLNK(inode->i_mode)) 2253: invalidate_mapping_pages(inode->i_mapping, 0, -1); 2254: } 2255: extern int invalidate_inode_pages2(struct address_space *mapping); 2256: extern int invalidate_inode_pages2_range(struct address_space *mapping, 2257: pgoff_t start, pgoff_t end); 2258: extern int write_inode_now(struct inode *, int); 2259: extern int filemap_fdatawrite(struct address_space *); 2260: extern int filemap_flush(struct address_space *); 2261: extern int filemap_fdatawait(struct address_space *); 2262: extern int filemap_fdatawait_range(struct address_space *, loff_t lstart, 2263: loff_t lend); 2264: extern int filemap_write_and_wait(struct address_space *mapping); 2265: extern int filemap_write_and_wait_range(struct address_space *mapping, 2266: loff_t lstart, loff_t lend); 2267: extern int __filemap_fdatawrite_range(struct address_space *mapping, 2268: loff_t start, loff_t end, int sync_mode); 2269: extern int filemap_fdatawrite_range(struct address_space *mapping, 2270: loff_t start, loff_t end); 2271: 2272: extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end, 2273: int datasync); 2274: extern int vfs_fsync(struct file *file, int datasync); 2275: extern int generic_write_sync(struct file *file, loff_t pos, loff_t count); 2276: extern void emergency_sync(void); 2277: extern void emergency_remount(void); 2278: #ifdef CONFIG_BLOCK 2279: extern sector_t bmap(struct inode *, sector_t); 2280: #endif 2281: extern int notify_change(struct dentry *, struct iattr *, struct inode **); 2282: extern int inode_permission(struct inode *, int); 2283: extern int generic_permission(struct inode *, int); 2284: 2285: static inline bool execute_ok(struct inode *inode) 2286: { 2287: return (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode); 2288: } 2289: 2290: static inline struct inode *file_inode(struct file *f) 2291: { 2292: return f->f_inode; 2293: } 2294: 2295: static inline void file_start_write(struct file *file) 2296: { 2297: if (!S_ISREG(file_inode(file)->i_mode)) 2298: return; 2299: __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, true); 2300: } 2301: 2302: static inline bool file_start_write_trylock(struct file *file) 2303: { 2304: if (!S_ISREG(file_inode(file)->i_mode)) 2305: return true; 2306: return __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, false); 2307: } 2308: 2309: static inline void file_end_write(struct file *file) 2310: { 2311: if (!S_ISREG(file_inode(file)->i_mode)) 2312: return; 2313: __sb_end_write(file_inode(file)->i_sb, SB_FREEZE_WRITE); 2314: } 2315: 2316: /* 2317: * get_write_access() gets write permission for a file. 2318: * put_write_access() releases this write permission. 2319: * This is used for regular files. 2320: * We cannot support write (and maybe mmap read-write shared) accesses and 2321: * MAP_DENYWRITE mmappings simultaneously. The i_writecount field of an inode 2322: * can have the following values: 2323: * 0: no writers, no VM_DENYWRITE mappings 2324: * < 0: (-i_writecount) vm_area_structs with VM_DENYWRITE set exist 2325: * > 0: (i_writecount) users are writing to the file. 2326: * 2327: * Normally we operate on that counter with atomic_{inc,dec} and it's safe 2328: * except for the cases where we don't hold i_writecount yet. Then we need to 2329: * use {get,deny}_write_access() - these functions check the sign and refuse 2330: * to do the change if sign is wrong. 2331: */ 2332: static inline int get_write_access(struct inode *inode) 2333: { 2334: return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY; 2335: } 2336: static inline int deny_write_access(struct file *file) 2337: { 2338: struct inode *inode = file_inode(file); 2339: return atomic_dec_unless_positive(&inode->i_writecount) ? 0 : -ETXTBSY; 2340: } 2341: static inline void put_write_access(struct inode * inode) 2342: { 2343: atomic_dec(&inode->i_writecount); 2344: } 2345: static inline void allow_write_access(struct file *file) 2346: { 2347: if (file) 2348: atomic_inc(&file_inode(file)->i_writecount); 2349: } 2350: static inline bool inode_is_open_for_write(const struct inode *inode) 2351: { 2352: return atomic_read(&inode->i_writecount) > 0; 2353: } 2354: 2355: #ifdef CONFIG_IMA 2356: static inline void i_readcount_dec(struct inode *inode) 2357: { 2358: BUG_ON(!atomic_read(&inode->i_readcount)); 2359: atomic_dec(&inode->i_readcount); 2360: } 2361: static inline void i_readcount_inc(struct inode *inode) 2362: { 2363: atomic_inc(&inode->i_readcount); 2364: } 2365: #else 2366: static inline void i_readcount_dec(struct inode *inode) 2367: { 2368: return; 2369: } 2370: static inline void i_readcount_inc(struct inode *inode) 2371: { 2372: return; 2373: } 2374: #endif 2375: extern int do_pipe_flags(int *, int); 2376: 2377: extern int kernel_read(struct file *, loff_t, char *, unsigned long); 2378: extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t); 2379: extern struct file * open_exec(const char *); 2380: 2381: /* fs/dcache.c -- generic fs support functions */ 2382: extern int is_subdir(struct dentry *, struct dentry *); 2383: extern int path_is_under(struct path *, struct path *); 2384: 2385: #include <linux/err.h> 2386: 2387: /* needed for stackable file system support */ 2388: extern loff_t default_llseek(struct file *file, loff_t offset, int whence); 2389: 2390: extern loff_t vfs_llseek(struct file *file, loff_t offset, int whence); 2391: 2392: extern int inode_init_always(struct super_block *, struct inode *); 2393: extern void inode_init_once(struct inode *); 2394: extern void address_space_init_once(struct address_space *mapping); 2395: extern struct inode * igrab(struct inode *); 2396: extern ino_t iunique(struct super_block *, ino_t); 2397: extern int inode_needs_sync(struct inode *inode); 2398: extern int generic_delete_inode(struct inode *inode); 2399: static inline int generic_drop_inode(struct inode *inode) 2400: { 2401: return !inode->i_nlink || inode_unhashed(inode); 2402: } 2403: 2404: extern struct inode *ilookup5_nowait(struct super_block *sb, 2405: unsigned long hashval, int (*test)(struct inode *, void *), 2406: void *data); 2407: extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval, 2408: int (*test)(struct inode *, void *), void *data); 2409: extern struct inode *ilookup(struct super_block *sb, unsigned long ino); 2410: 2411: extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *); 2412: extern struct inode * iget_locked(struct super_block *, unsigned long); 2413: extern int insert_inode_locked4(struct inode *, unsigned long, int (*test)(struct inode *, void *), void *); 2414: extern int insert_inode_locked(struct inode *); 2415: #ifdef CONFIG_DEBUG_LOCK_ALLOC 2416: extern void lockdep_annotate_inode_mutex_key(struct inode *inode); 2417: #else 2418: static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { }; 2419: #endif 2420: extern void unlock_new_inode(struct inode *); 2421: extern unsigned int get_next_ino(void); 2422: 2423: extern void __iget(struct inode * inode); 2424: extern void iget_failed(struct inode *); 2425: extern void clear_inode(struct inode *); 2426: extern void __destroy_inode(struct inode *); 2427: extern struct inode *new_inode_pseudo(struct super_block *sb); 2428: extern struct inode *new_inode(struct super_block *sb); 2429: extern void free_inode_nonrcu(struct inode *inode); 2430: extern int should_remove_suid(struct dentry *); 2431: extern int file_remove_suid(struct file *); 2432: 2433: extern void __insert_inode_hash(struct inode *, unsigned long hashval); 2434: static inline void insert_inode_hash(struct inode *inode) 2435: { 2436: __insert_inode_hash(inode, inode->i_ino); 2437: } 2438: 2439: extern void __remove_inode_hash(struct inode *); 2440: static inline void remove_inode_hash(struct inode *inode) 2441: { 2442: if (!inode_unhashed(inode)) 2443: __remove_inode_hash(inode); 2444: } 2445: 2446: extern void inode_sb_list_add(struct inode *inode); 2447: 2448: #ifdef CONFIG_BLOCK 2449: extern void submit_bio(int, struct bio *); 2450: extern int bdev_read_only(struct block_device *); 2451: #endif 2452: extern int set_blocksize(struct block_device *, int); 2453: extern int sb_set_blocksize(struct super_block *, int); 2454: extern int sb_min_blocksize(struct super_block *, int); 2455: 2456: extern int generic_file_mmap(struct file *, struct vm_area_struct *); 2457: extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *); 2458: extern int generic_file_remap_pages(struct vm_area_struct *, unsigned long addr, 2459: unsigned long size, pgoff_t pgoff); 2460: extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size); 2461: int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk); 2462: extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t); 2463: extern ssize_t __generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, 2464: loff_t *); 2465: extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t); 2466: extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *, 2467: unsigned long *, loff_t, loff_t *, size_t, size_t); 2468: extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *, 2469: unsigned long, loff_t, loff_t *, size_t, ssize_t); 2470: extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos); 2471: extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos); 2472: extern int generic_segment_checks(const struct iovec *iov, 2473: unsigned long *nr_segs, size_t *count, int access_flags); 2474: 2475: /* fs/block_dev.c */ 2476: extern ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov, 2477: unsigned long nr_segs, loff_t pos); 2478: extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end, 2479: int datasync); 2480: extern void block_sync_page(struct page *page); 2481: 2482: /* fs/splice.c */ 2483: extern ssize_t generic_file_splice_read(struct file *, loff_t *, 2484: struct pipe_inode_info *, size_t, unsigned int); 2485: extern ssize_t default_file_splice_read(struct file *, loff_t *, 2486: struct pipe_inode_info *, size_t, unsigned int); 2487: extern ssize_t generic_file_splice_write(struct pipe_inode_info *, 2488: struct file *, loff_t *, size_t, unsigned int); 2489: extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, 2490: struct file *out, loff_t *, size_t len, unsigned int flags); 2491: 2492: extern void 2493: file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping); 2494: extern loff_t noop_llseek(struct file *file, loff_t offset, int whence); 2495: extern loff_t no_llseek(struct file *file, loff_t offset, int whence); 2496: extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize); 2497: extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence); 2498: extern loff_t generic_file_llseek_size(struct file *file, loff_t offset, 2499: int whence, loff_t maxsize, loff_t eof); 2500: extern loff_t fixed_size_llseek(struct file *file, loff_t offset, 2501: int whence, loff_t size); 2502: extern int generic_file_open(struct inode * inode, struct file * filp); 2503: extern int nonseekable_open(struct inode * inode, struct file * filp); 2504: 2505: #ifdef CONFIG_FS_XIP 2506: extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len, 2507: loff_t *ppos); 2508: extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma); 2509: extern ssize_t xip_file_write(struct file *filp, const char __user *buf, 2510: size_t len, loff_t *ppos); 2511: extern int xip_truncate_page(struct address_space *mapping, loff_t from); 2512: #else 2513: static inline int xip_truncate_page(struct address_space *mapping, loff_t from) 2514: { 2515: return 0; 2516: } 2517: #endif 2518: 2519: #ifdef CONFIG_BLOCK 2520: typedef void (dio_submit_t)(int rw, struct bio *bio, struct inode *inode, 2521: loff_t file_offset); 2522: 2523: enum { 2524: /* need locking between buffered and direct access */ 2525: DIO_LOCKING = 0x01, 2526: 2527: /* filesystem does not support filling holes */ 2528: DIO_SKIP_HOLES = 0x02, 2529: }; 2530: 2531: void dio_end_io(struct bio *bio, int error); 2532: 2533: ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode, 2534: struct block_device *bdev, const struct iovec *iov, loff_t offset, 2535: unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io, 2536: dio_submit_t submit_io, int flags); 2537: 2538: static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb, 2539: struct inode *inode, const struct iovec *iov, loff_t offset, 2540: unsigned long nr_segs, get_block_t get_block) 2541: { 2542: return __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov, 2543: offset, nr_segs, get_block, NULL, NULL, 2544: DIO_LOCKING | DIO_SKIP_HOLES); 2545: } 2546: #endif 2547: 2548: void inode_dio_wait(struct inode *inode); 2549: void inode_dio_done(struct inode *inode); 2550: 2551: extern const struct file_operations generic_ro_fops; 2552: 2553: #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m)) 2554: 2555: extern int vfs_readlink(struct dentry *, char __user *, int, const char *); 2556: extern int page_readlink(struct dentry *, char __user *, int); 2557: extern void *page_follow_link_light(struct dentry *, struct nameidata *); 2558: extern void page_put_link(struct dentry *, struct nameidata *, void *); 2559: extern int __page_symlink(struct inode *inode, const char *symname, int len, 2560: int nofs); 2561: extern int page_symlink(struct inode *inode, const char *symname, int len); 2562: extern const struct inode_operations page_symlink_inode_operations; 2563: extern void kfree_put_link(struct dentry *, struct nameidata *, void *); 2564: extern int generic_readlink(struct dentry *, char __user *, int); 2565: extern void generic_fillattr(struct inode *, struct kstat *); 2566: int vfs_getattr_nosec(struct path *path, struct kstat *stat); 2567: extern int vfs_getattr(struct path *, struct kstat *); 2568: void __inode_add_bytes(struct inode *inode, loff_t bytes); 2569: void inode_add_bytes(struct inode *inode, loff_t bytes); 2570: void __inode_sub_bytes(struct inode *inode, loff_t bytes); 2571: void inode_sub_bytes(struct inode *inode, loff_t bytes); 2572: loff_t inode_get_bytes(struct inode *inode); 2573: void inode_set_bytes(struct inode *inode, loff_t bytes); 2574: 2575: extern int vfs_readdir(struct file *, filldir_t, void *); 2576: extern int iterate_dir(struct file *, struct dir_context *); 2577: 2578: extern int vfs_stat(const char __user *, struct kstat *); 2579: extern int vfs_lstat(const char __user *, struct kstat *); 2580: extern int vfs_fstat(unsigned int, struct kstat *); 2581: extern int vfs_fstatat(int , const char __user *, struct kstat *, int); 2582: 2583: extern int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, 2584: unsigned long arg); 2585: extern int __generic_block_fiemap(struct inode *inode, 2586: struct fiemap_extent_info *fieinfo, 2587: loff_t start, loff_t len, 2588: get_block_t *get_block); 2589: extern int generic_block_fiemap(struct inode *inode, 2590: struct fiemap_extent_info *fieinfo, u64 start, 2591: u64 len, get_block_t *get_block); 2592: 2593: extern void get_filesystem(struct file_system_type *fs); 2594: extern void put_filesystem(struct file_system_type *fs); 2595: extern struct file_system_type *get_fs_type(const char *name); 2596: extern struct super_block *get_super(struct block_device *); 2597: extern struct super_block *get_super_thawed(struct block_device *); 2598: extern struct super_block *get_active_super(struct block_device *bdev); 2599: extern void drop_super(struct super_block *sb); 2600: extern void iterate_supers(void (*)(struct super_block *, void *), void *); 2601: extern void iterate_supers_type(struct file_system_type *, 2602: void (*)(struct super_block *, void *), void *); 2603: 2604: extern int dcache_dir_open(struct inode *, struct file *); 2605: extern int dcache_dir_close(struct inode *, struct file *); 2606: extern loff_t dcache_dir_lseek(struct file *, loff_t, int); 2607: extern int dcache_readdir(struct file *, struct dir_context *); 2608: extern int simple_setattr(struct dentry *, struct iattr *); 2609: extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *); 2610: extern int simple_statfs(struct dentry *, struct kstatfs *); 2611: extern int simple_open(struct inode *inode, struct file *file); 2612: extern int simple_link(struct dentry *, struct inode *, struct dentry *); 2613: extern int simple_unlink(struct inode *, struct dentry *); 2614: extern int simple_rmdir(struct inode *, struct dentry *); 2615: extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *); 2616: extern int noop_fsync(struct file *, loff_t, loff_t, int); 2617: extern int simple_empty(struct dentry *); 2618: extern int simple_readpage(struct file *file, struct page *page); 2619: extern int simple_write_begin(struct file *file, struct address_space *mapping, 2620: loff_t pos, unsigned len, unsigned flags, 2621: struct page **pagep, void **fsdata); 2622: extern int simple_write_end(struct file *file, struct address_space *mapping, 2623: loff_t pos, unsigned len, unsigned copied, 2624: struct page *page, void *fsdata); 2625: extern int always_delete_dentry(const struct dentry *); 2626: extern struct inode *alloc_anon_inode(struct super_block *); 2627: extern const struct dentry_operations simple_dentry_operations; 2628: 2629: extern struct dentry *simple_lookup(struct inode *, struct dentry *, unsigned int flags); 2630: extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *); 2631: extern const struct file_operations simple_dir_operations; 2632: extern const struct inode_operations simple_dir_inode_operations; 2633: struct tree_descr { char *name; const struct file_operations *ops; int mode; }; 2634: struct dentry *d_alloc_name(struct dentry *, const char *); 2635: extern int simple_fill_super(struct super_block *, unsigned long, struct tree_descr *); 2636: extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count); 2637: extern void simple_release_fs(struct vfsmount **mount, int *count); 2638: 2639: extern ssize_t simple_read_from_buffer(void __user *to, size_t count, 2640: loff_t *ppos, const void *from, size_t available); 2641: extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos, 2642: const void __user *from, size_t count); 2643: 2644: extern int generic_file_fsync(struct file *, loff_t, loff_t, int); 2645: 2646: extern int generic_check_addressable(unsigned, u64); 2647: 2648: #ifdef CONFIG_MIGRATION 2649: extern int buffer_migrate_page(struct address_space *, 2650: struct page *, struct page *, 2651: enum migrate_mode); 2652: #else 2653: #define buffer_migrate_page NULL 2654: #endif 2655: 2656: extern int inode_change_ok(const struct inode *, struct iattr *); 2657: extern int inode_newsize_ok(const struct inode *, loff_t offset); 2658: extern void setattr_copy(struct inode *inode, const struct iattr *attr); 2659: 2660: extern int file_update_time(struct file *file); 2661: 2662: extern int generic_show_options(struct seq_file *m, struct dentry *root); 2663: extern void save_mount_options(struct super_block *sb, char *options); 2664: extern void replace_mount_options(struct super_block *sb, char *options); 2665: 2666: static inline ino_t parent_ino(struct dentry *dentry) 2667: { 2668: ino_t res; 2669: 2670: /* 2671: * Don't strictly need d_lock here? If the parent ino could change 2672: * then surely we'd have a deeper race in the caller? 2673: */ 2674: spin_lock(&dentry->d_lock); 2675: res = dentry->d_parent->d_inode->i_ino; 2676: spin_unlock(&dentry->d_lock); 2677: return res; 2678: } 2679: 2680: /* Transaction based IO helpers */ 2681: 2682: /* 2683: * An argresp is stored in an allocated page and holds the 2684: * size of the argument or response, along with its content 2685: */ 2686: struct simple_transaction_argresp { 2687: ssize_t size; 2688: char data[0]; 2689: }; 2690: 2691: #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp)) 2692: 2693: char *simple_transaction_get(struct file *file, const char __user *buf, 2694: size_t size); 2695: ssize_t simple_transaction_read(struct file *file, char __user *buf, 2696: size_t size, loff_t *pos); 2697: int simple_transaction_release(struct inode *inode, struct file *file); 2698: 2699: void simple_transaction_set(struct file *file, size_t n); 2700: 2701: /* 2702: * simple attribute files 2703: * 2704: * These attributes behave similar to those in sysfs: 2705: * 2706: * Writing to an attribute immediately sets a value, an open file can be 2707: * written to multiple times. 2708: * 2709: * Reading from an attribute creates a buffer from the value that might get 2710: * read with multiple read calls. When the attribute has been read 2711: * completely, no further read calls are possible until the file is opened 2712: * again. 2713: * 2714: * All attributes contain a text representation of a numeric value 2715: * that are accessed with the get() and set() functions. 2716: */ 2717: #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \ 2718: static int __fops ## _open(struct inode *inode, struct file *file) \ 2719: { \ 2720: __simple_attr_check_format(__fmt, 0ull); \ 2721: return simple_attr_open(inode, file, __get, __set, __fmt); \ 2722: } \ 2723: static const struct file_operations __fops = { \ 2724: .owner = THIS_MODULE, \ 2725: .open = __fops ## _open, \ 2726: .release = simple_attr_release, \ 2727: .read = simple_attr_read, \ 2728: .write = simple_attr_write, \ 2729: .llseek = generic_file_llseek, \ 2730: }; 2731: 2732: static inline __printf(1, 2) 2733: void __simple_attr_check_format(const char *fmt, ...) 2734: { 2735: /* don't do anything, just let the compiler check the arguments; */ 2736: } 2737: 2738: int simple_attr_open(struct inode *inode, struct file *file, 2739: int (*get)(void *, u64 *), int (*set)(void *, u64), 2740: const char *fmt); 2741: int simple_attr_release(struct inode *inode, struct file *file); 2742: ssize_t simple_attr_read(struct file *file, char __user *buf, 2743: size_t len, loff_t *ppos); 2744: ssize_t simple_attr_write(struct file *file, const char __user *buf, 2745: size_t len, loff_t *ppos); 2746: 2747: struct ctl_table; 2748: int proc_nr_files(struct ctl_table *table, int write, 2749: void __user *buffer, size_t *lenp, loff_t *ppos); 2750: int proc_nr_dentry(struct ctl_table *table, int write, 2751: void __user *buffer, size_t *lenp, loff_t *ppos); 2752: int proc_nr_inodes(struct ctl_table *table, int write, 2753: void __user *buffer, size_t *lenp, loff_t *ppos); 2754: int __init get_filesystem_list(char *buf); 2755: 2756: #define __FMODE_EXEC ((__force int) FMODE_EXEC) 2757: #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY) 2758: 2759: #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE]) 2760: #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \ 2761: (flag & __FMODE_NONOTIFY))) 2762: 2763: static inline int is_sxid(umode_t mode) 2764: { 2765: return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP)); 2766: } 2767: 2768: static inline void inode_has_no_xattr(struct inode *inode) 2769: { 2770: if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & MS_NOSEC)) 2771: inode->i_flags |= S_NOSEC; 2772: } 2773: 2774: static inline bool dir_emit(struct dir_context *ctx, 2775: const char *name, int namelen, 2776: u64 ino, unsigned type) 2777: { 2778: return ctx->actor(ctx, name, namelen, ctx->pos, ino, type) == 0; 2779: } 2780: static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx) 2781: { 2782: return ctx->actor(ctx, ".", 1, ctx->pos, 2783: file->f_path.dentry->d_inode->i_ino, DT_DIR) == 0; 2784: } 2785: static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx) 2786: { 2787: return ctx->actor(ctx, "..", 2, ctx->pos, 2788: parent_ino(file->f_path.dentry), DT_DIR) == 0; 2789: } 2790: static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx) 2791: { 2792: if (ctx->pos == 0) { 2793: if (!dir_emit_dot(file, ctx)) 2794: return false; 2795: ctx->pos = 1; 2796: } 2797: if (ctx->pos == 1) { 2798: if (!dir_emit_dotdot(file, ctx)) 2799: return false; 2800: ctx->pos = 2; 2801: } 2802: return true; 2803: } 2804: static inline bool dir_relax(struct inode *inode) 2805: { 2806: mutex_unlock(&inode->i_mutex); 2807: mutex_lock(&inode->i_mutex); 2808: return !IS_DEADDIR(inode); 2809: } 2810: 2811: #endif /* _LINUX_FS_H */ 2812: