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fs/locks.c
58.3 KB
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/* * linux/fs/locks.c * * Provide support for fcntl()'s F_GETLK, F_SETLK, and F_SETLKW calls. * Doug Evans (dje@spiff.uucp), August 07, 1992 * * Deadlock detection added. * FIXME: one thing isn't handled yet: * - mandatory locks (requires lots of changes elsewhere) * Kelly Carmichael (kelly@[142.24.8.65]), September 17, 1994. * * Miscellaneous edits, and a total rewrite of posix_lock_file() code. * Kai Petzke (wpp@marie.physik.tu-berlin.de), 1994 * * Converted file_lock_table to a linked list from an array, which eliminates * the limits on how many active file locks are open. * Chad Page (pageone@netcom.com), November 27, 1994 * * Removed dependency on file descriptors. dup()'ed file descriptors now * get the same locks as the original file descriptors, and a close() on * any file descriptor removes ALL the locks on the file for the current * process. Since locks still depend on the process id, locks are inherited * after an exec() but not after a fork(). This agrees with POSIX, and both * BSD and SVR4 practice. * Andy Walker (andy@lysaker.kvaerner.no), February 14, 1995 * * Scrapped free list which is redundant now that we allocate locks * dynamically with kmalloc()/kfree(). * Andy Walker (andy@lysaker.kvaerner.no), February 21, 1995 * * Implemented two lock personalities - FL_FLOCK and FL_POSIX. * * FL_POSIX locks are created with calls to fcntl() and lockf() through the * fcntl() system call. They have the semantics described above. * * FL_FLOCK locks are created with calls to flock(), through the flock() * system call, which is new. Old C libraries implement flock() via fcntl() * and will continue to use the old, broken implementation. * * FL_FLOCK locks follow the 4.4 BSD flock() semantics. They are associated * with a file pointer (filp). As a result they can be shared by a parent * process and its children after a fork(). They are removed when the last * file descriptor referring to the file pointer is closed (unless explicitly * unlocked). * * FL_FLOCK locks never deadlock, an existing lock is always removed before * upgrading from shared to exclusive (or vice versa). When this happens * any processes blocked by the current lock are woken up and allowed to * run before the new lock is applied. * Andy Walker (andy@lysaker.kvaerner.no), June 09, 1995 * * Removed some race conditions in flock_lock_file(), marked other possible * races. Just grep for FIXME to see them. * Dmitry Gorodchanin (pgmdsg@ibi.com), February 09, 1996. * * Addressed Dmitry's concerns. Deadlock checking no longer recursive. * Lock allocation changed to GFP_ATOMIC as we can't afford to sleep * once we've checked for blocking and deadlocking. * Andy Walker (andy@lysaker.kvaerner.no), April 03, 1996. * * Initial implementation of mandatory locks. SunOS turned out to be * a rotten model, so I implemented the "obvious" semantics. * See 'Documentation/mandatory.txt' for details. * Andy Walker (andy@lysaker.kvaerner.no), April 06, 1996. * * Don't allow mandatory locks on mmap()'ed files. Added simple functions to * check if a file has mandatory locks, used by mmap(), open() and creat() to * see if system call should be rejected. Ref. HP-UX/SunOS/Solaris Reference * Manual, Section 2. * Andy Walker (andy@lysaker.kvaerner.no), April 09, 1996. * * Tidied up block list handling. Added '/proc/locks' interface. * Andy Walker (andy@lysaker.kvaerner.no), April 24, 1996. * * Fixed deadlock condition for pathological code that mixes calls to * flock() and fcntl(). * Andy Walker (andy@lysaker.kvaerner.no), April 29, 1996. * * Allow only one type of locking scheme (FL_POSIX or FL_FLOCK) to be in use * for a given file at a time. Changed the CONFIG_LOCK_MANDATORY scheme to * guarantee sensible behaviour in the case where file system modules might * be compiled with different options than the kernel itself. * Andy Walker (andy@lysaker.kvaerner.no), May 15, 1996. * * Added a couple of missing wake_up() calls. Thanks to Thomas Meckel * (Thomas.Meckel@mni.fh-giessen.de) for spotting this. * Andy Walker (andy@lysaker.kvaerner.no), May 15, 1996. * * Changed FL_POSIX locks to use the block list in the same way as FL_FLOCK * locks. Changed process synchronisation to avoid dereferencing locks that * have already been freed. * Andy Walker (andy@lysaker.kvaerner.no), Sep 21, 1996. * * Made the block list a circular list to minimise searching in the list. * Andy Walker (andy@lysaker.kvaerner.no), Sep 25, 1996. * * Made mandatory locking a mount option. Default is not to allow mandatory * locking. * Andy Walker (andy@lysaker.kvaerner.no), Oct 04, 1996. * * Some adaptations for NFS support. * Olaf Kirch (okir@monad.swb.de), Dec 1996, * * Fixed /proc/locks interface so that we can't overrun the buffer we are handed. * Andy Walker (andy@lysaker.kvaerner.no), May 12, 1997. * * Use slab allocator instead of kmalloc/kfree. * Use generic list implementation from <linux/list.h>. * Sped up posix_locks_deadlock by only considering blocked locks. * Matthew Wilcox <willy@debian.org>, March, 2000. * * Leases and LOCK_MAND * Matthew Wilcox <willy@debian.org>, June, 2000. * Stephen Rothwell <sfr@canb.auug.org.au>, June, 2000. */ #include <linux/capability.h> #include <linux/file.h> |
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#include <linux/fdtable.h> |
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#include <linux/fs.h> #include <linux/init.h> #include <linux/module.h> #include <linux/security.h> #include <linux/slab.h> |
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#include <linux/syscalls.h> #include <linux/time.h> |
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#include <linux/rcupdate.h> |
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#include <linux/pid_namespace.h> |
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|
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#include <asm/uaccess.h> #define IS_POSIX(fl) (fl->fl_flags & FL_POSIX) #define IS_FLOCK(fl) (fl->fl_flags & FL_FLOCK) #define IS_LEASE(fl) (fl->fl_flags & FL_LEASE) int leases_enable = 1; int lease_break_time = 45; #define for_each_lock(inode, lockp) \ for (lockp = &inode->i_flock; *lockp != NULL; lockp = &(*lockp)->fl_next) |
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static LIST_HEAD(file_lock_list); |
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static LIST_HEAD(blocked_list); |
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static DEFINE_SPINLOCK(file_lock_lock); |
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|
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/* * Protects the two list heads above, plus the inode->i_flock list |
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*/ void lock_flocks(void) { |
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spin_lock(&file_lock_lock); |
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} EXPORT_SYMBOL_GPL(lock_flocks); void unlock_flocks(void) { |
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spin_unlock(&file_lock_lock); |
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} EXPORT_SYMBOL_GPL(unlock_flocks); |
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static struct kmem_cache *filelock_cache __read_mostly; |
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/* Allocate an empty lock structure. */ |
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struct file_lock *locks_alloc_lock(void) |
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{ |
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return kmem_cache_alloc(filelock_cache, GFP_KERNEL); |
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} |
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EXPORT_SYMBOL_GPL(locks_alloc_lock); |
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|
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void locks_release_private(struct file_lock *fl) |
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{ if (fl->fl_ops) { if (fl->fl_ops->fl_release_private) fl->fl_ops->fl_release_private(fl); fl->fl_ops = NULL; } if (fl->fl_lmops) { if (fl->fl_lmops->fl_release_private) fl->fl_lmops->fl_release_private(fl); fl->fl_lmops = NULL; } } |
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EXPORT_SYMBOL_GPL(locks_release_private); |
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|
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/* Free a lock which is not in use. */ |
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void locks_free_lock(struct file_lock *fl) |
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{ |
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BUG_ON(waitqueue_active(&fl->fl_wait)); BUG_ON(!list_empty(&fl->fl_block)); BUG_ON(!list_empty(&fl->fl_link)); |
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|
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locks_release_private(fl); |
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kmem_cache_free(filelock_cache, fl); } |
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EXPORT_SYMBOL(locks_free_lock); |
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void locks_init_lock(struct file_lock *fl) { INIT_LIST_HEAD(&fl->fl_link); INIT_LIST_HEAD(&fl->fl_block); init_waitqueue_head(&fl->fl_wait); fl->fl_next = NULL; fl->fl_fasync = NULL; fl->fl_owner = NULL; fl->fl_pid = 0; |
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fl->fl_nspid = NULL; |
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fl->fl_file = NULL; fl->fl_flags = 0; fl->fl_type = 0; fl->fl_start = fl->fl_end = 0; fl->fl_ops = NULL; fl->fl_lmops = NULL; } EXPORT_SYMBOL(locks_init_lock); /* * Initialises the fields of the file lock which are invariant for * free file_locks. */ |
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static void init_once(void *foo) |
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{ struct file_lock *lock = (struct file_lock *) foo; |
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locks_init_lock(lock); } |
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static void locks_copy_private(struct file_lock *new, struct file_lock *fl) { if (fl->fl_ops) { if (fl->fl_ops->fl_copy_lock) fl->fl_ops->fl_copy_lock(new, fl); new->fl_ops = fl->fl_ops; } |
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if (fl->fl_lmops) |
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new->fl_lmops = fl->fl_lmops; |
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} |
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/* * Initialize a new lock from an existing file_lock structure. */ |
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void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl) |
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{ new->fl_owner = fl->fl_owner; new->fl_pid = fl->fl_pid; |
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new->fl_file = NULL; |
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new->fl_flags = fl->fl_flags; new->fl_type = fl->fl_type; new->fl_start = fl->fl_start; new->fl_end = fl->fl_end; |
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new->fl_ops = NULL; new->fl_lmops = NULL; } |
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EXPORT_SYMBOL(__locks_copy_lock); |
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void locks_copy_lock(struct file_lock *new, struct file_lock *fl) { locks_release_private(new); __locks_copy_lock(new, fl); new->fl_file = fl->fl_file; |
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new->fl_ops = fl->fl_ops; new->fl_lmops = fl->fl_lmops; |
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locks_copy_private(new, fl); |
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} EXPORT_SYMBOL(locks_copy_lock); static inline int flock_translate_cmd(int cmd) { if (cmd & LOCK_MAND) return cmd & (LOCK_MAND | LOCK_RW); switch (cmd) { case LOCK_SH: return F_RDLCK; case LOCK_EX: return F_WRLCK; case LOCK_UN: return F_UNLCK; } return -EINVAL; } /* Fill in a file_lock structure with an appropriate FLOCK lock. */ static int flock_make_lock(struct file *filp, struct file_lock **lock, unsigned int cmd) { struct file_lock *fl; int type = flock_translate_cmd(cmd); if (type < 0) return type; fl = locks_alloc_lock(); if (fl == NULL) return -ENOMEM; fl->fl_file = filp; fl->fl_pid = current->tgid; fl->fl_flags = FL_FLOCK; fl->fl_type = type; fl->fl_end = OFFSET_MAX; *lock = fl; return 0; } static int assign_type(struct file_lock *fl, int type) { switch (type) { case F_RDLCK: case F_WRLCK: case F_UNLCK: fl->fl_type = type; break; default: return -EINVAL; } return 0; } /* Verify a "struct flock" and copy it to a "struct file_lock" as a POSIX * style lock. */ static int flock_to_posix_lock(struct file *filp, struct file_lock *fl, struct flock *l) { off_t start, end; switch (l->l_whence) { |
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case SEEK_SET: |
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start = 0; break; |
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case SEEK_CUR: |
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start = filp->f_pos; break; |
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case SEEK_END: |
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start = i_size_read(filp->f_path.dentry->d_inode); |
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break; default: return -EINVAL; } /* POSIX-1996 leaves the case l->l_len < 0 undefined; POSIX-2001 defines it. */ start += l->l_start; |
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if (start < 0) return -EINVAL; fl->fl_end = OFFSET_MAX; if (l->l_len > 0) { end = start + l->l_len - 1; fl->fl_end = end; } else if (l->l_len < 0) { |
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end = start - 1; |
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fl->fl_end = end; |
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start += l->l_len; |
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if (start < 0) return -EINVAL; |
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} |
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fl->fl_start = start; /* we record the absolute position */ |
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if (fl->fl_end < fl->fl_start) return -EOVERFLOW; |
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fl->fl_owner = current->files; fl->fl_pid = current->tgid; fl->fl_file = filp; fl->fl_flags = FL_POSIX; fl->fl_ops = NULL; fl->fl_lmops = NULL; return assign_type(fl, l->l_type); } #if BITS_PER_LONG == 32 static int flock64_to_posix_lock(struct file *filp, struct file_lock *fl, struct flock64 *l) { loff_t start; switch (l->l_whence) { |
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case SEEK_SET: |
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start = 0; break; |
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case SEEK_CUR: |
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start = filp->f_pos; break; |
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case SEEK_END: |
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start = i_size_read(filp->f_path.dentry->d_inode); |
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break; default: return -EINVAL; } |
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start += l->l_start; if (start < 0) |
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return -EINVAL; |
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fl->fl_end = OFFSET_MAX; if (l->l_len > 0) { fl->fl_end = start + l->l_len - 1; } else if (l->l_len < 0) { fl->fl_end = start - 1; start += l->l_len; if (start < 0) return -EINVAL; } |
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fl->fl_start = start; /* we record the absolute position */ |
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if (fl->fl_end < fl->fl_start) return -EOVERFLOW; |
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fl->fl_owner = current->files; fl->fl_pid = current->tgid; fl->fl_file = filp; fl->fl_flags = FL_POSIX; fl->fl_ops = NULL; fl->fl_lmops = NULL; |
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return assign_type(fl, l->l_type); |
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} #endif /* default lease lock manager operations */ static void lease_break_callback(struct file_lock *fl) { kill_fasync(&fl->fl_fasync, SIGIO, POLL_MSG); } static void lease_release_private_callback(struct file_lock *fl) { if (!fl->fl_file) return; f_delown(fl->fl_file); fl->fl_file->f_owner.signum = 0; } |
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static const struct lock_manager_operations lease_manager_ops = { |
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.fl_break = lease_break_callback, .fl_release_private = lease_release_private_callback, |
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.fl_change = lease_modify, }; /* * Initialize a lease, use the default lock manager operations */ static int lease_init(struct file *filp, int type, struct file_lock *fl) { |
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if (assign_type(fl, type) != 0) return -EINVAL; |
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fl->fl_owner = current->files; fl->fl_pid = current->tgid; fl->fl_file = filp; fl->fl_flags = FL_LEASE; |
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fl->fl_start = 0; fl->fl_end = OFFSET_MAX; fl->fl_ops = NULL; fl->fl_lmops = &lease_manager_ops; return 0; } /* Allocate a file_lock initialised to this type of lease */ |
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static struct file_lock *lease_alloc(struct file *filp, int type) |
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{ struct file_lock *fl = locks_alloc_lock(); |
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int error = -ENOMEM; |
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if (fl == NULL) |
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return ERR_PTR(error); |
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error = lease_init(filp, type, fl); |
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if (error) { locks_free_lock(fl); |
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return ERR_PTR(error); |
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} |
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return fl; |
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} /* Check if two locks overlap each other. */ static inline int locks_overlap(struct file_lock *fl1, struct file_lock *fl2) { return ((fl1->fl_end >= fl2->fl_start) && (fl2->fl_end >= fl1->fl_start)); } /* * Check whether two locks have the same owner. */ |
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static int posix_same_owner(struct file_lock *fl1, struct file_lock *fl2) |
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{ if (fl1->fl_lmops && fl1->fl_lmops->fl_compare_owner) return fl2->fl_lmops == fl1->fl_lmops && fl1->fl_lmops->fl_compare_owner(fl1, fl2); return fl1->fl_owner == fl2->fl_owner; } /* Remove waiter from blocker's block list. * When blocker ends up pointing to itself then the list is empty. */ |
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static void __locks_delete_block(struct file_lock *waiter) |
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{ list_del_init(&waiter->fl_block); list_del_init(&waiter->fl_link); waiter->fl_next = NULL; } /* */ static void locks_delete_block(struct file_lock *waiter) { |
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lock_flocks(); |
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__locks_delete_block(waiter); |
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unlock_flocks(); |
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} /* Insert waiter into blocker's block list. * We use a circular list so that processes can be easily woken up in * the order they blocked. The documentation doesn't require this but * it seems like the reasonable thing to do. */ static void locks_insert_block(struct file_lock *blocker, struct file_lock *waiter) { |
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BUG_ON(!list_empty(&waiter->fl_block)); |
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list_add_tail(&waiter->fl_block, &blocker->fl_block); waiter->fl_next = blocker; if (IS_POSIX(blocker)) list_add(&waiter->fl_link, &blocked_list); } /* Wake up processes blocked waiting for blocker. * If told to wait then schedule the processes until the block list * is empty, otherwise empty the block list ourselves. */ static void locks_wake_up_blocks(struct file_lock *blocker) { while (!list_empty(&blocker->fl_block)) { |
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struct file_lock *waiter; waiter = list_first_entry(&blocker->fl_block, |
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struct file_lock, fl_block); __locks_delete_block(waiter); if (waiter->fl_lmops && waiter->fl_lmops->fl_notify) waiter->fl_lmops->fl_notify(waiter); else wake_up(&waiter->fl_wait); } } /* Insert file lock fl into an inode's lock list at the position indicated * by pos. At the same time add the lock to the global file lock list. */ static void locks_insert_lock(struct file_lock **pos, struct file_lock *fl) { list_add(&fl->fl_link, &file_lock_list); |
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fl->fl_nspid = get_pid(task_tgid(current)); |
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549 550 551 |
/* insert into file's list */ fl->fl_next = *pos; *pos = fl; |
1da177e4c Linux-2.6.12-rc2 |
552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 |
} /* * Delete a lock and then free it. * Wake up processes that are blocked waiting for this lock, * notify the FS that the lock has been cleared and * finally free the lock. */ static void locks_delete_lock(struct file_lock **thisfl_p) { struct file_lock *fl = *thisfl_p; *thisfl_p = fl->fl_next; fl->fl_next = NULL; list_del_init(&fl->fl_link); fasync_helper(0, fl->fl_file, 0, &fl->fl_fasync); if (fl->fl_fasync != NULL) { printk(KERN_ERR "locks_delete_lock: fasync == %p ", fl->fl_fasync); fl->fl_fasync = NULL; } |
ab1f16116 pid-namespaces-vs... |
574 575 576 577 |
if (fl->fl_nspid) { put_pid(fl->fl_nspid); fl->fl_nspid = NULL; } |
1da177e4c Linux-2.6.12-rc2 |
578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 |
locks_wake_up_blocks(fl); locks_free_lock(fl); } /* Determine if lock sys_fl blocks lock caller_fl. Common functionality * checks for shared/exclusive status of overlapping locks. */ static int locks_conflict(struct file_lock *caller_fl, struct file_lock *sys_fl) { if (sys_fl->fl_type == F_WRLCK) return 1; if (caller_fl->fl_type == F_WRLCK) return 1; return 0; } /* Determine if lock sys_fl blocks lock caller_fl. POSIX specific * checking before calling the locks_conflict(). */ static int posix_locks_conflict(struct file_lock *caller_fl, struct file_lock *sys_fl) { /* POSIX locks owned by the same process do not conflict with * each other. */ if (!IS_POSIX(sys_fl) || posix_same_owner(caller_fl, sys_fl)) return (0); /* Check whether they overlap */ if (!locks_overlap(caller_fl, sys_fl)) return 0; return (locks_conflict(caller_fl, sys_fl)); } /* Determine if lock sys_fl blocks lock caller_fl. FLOCK specific * checking before calling the locks_conflict(). */ static int flock_locks_conflict(struct file_lock *caller_fl, struct file_lock *sys_fl) { /* FLOCK locks referring to the same filp do not conflict with * each other. */ if (!IS_FLOCK(sys_fl) || (caller_fl->fl_file == sys_fl->fl_file)) return (0); if ((caller_fl->fl_type & LOCK_MAND) || (sys_fl->fl_type & LOCK_MAND)) return 0; return (locks_conflict(caller_fl, sys_fl)); } |
6d34ac199 locks: make posix... |
627 |
void |
9d6a8c5c2 locks: give posix... |
628 |
posix_test_lock(struct file *filp, struct file_lock *fl) |
1da177e4c Linux-2.6.12-rc2 |
629 630 |
{ struct file_lock *cfl; |
b89f43213 fs/locks.c: prepa... |
631 |
lock_flocks(); |
0f7fc9e4d [PATCH] VFS: chan... |
632 |
for (cfl = filp->f_path.dentry->d_inode->i_flock; cfl; cfl = cfl->fl_next) { |
1da177e4c Linux-2.6.12-rc2 |
633 634 |
if (!IS_POSIX(cfl)) continue; |
b842e240f locks: reverse or... |
635 |
if (posix_locks_conflict(fl, cfl)) |
1da177e4c Linux-2.6.12-rc2 |
636 637 |
break; } |
ab1f16116 pid-namespaces-vs... |
638 |
if (cfl) { |
9d6a8c5c2 locks: give posix... |
639 |
__locks_copy_lock(fl, cfl); |
ab1f16116 pid-namespaces-vs... |
640 |
if (cfl->fl_nspid) |
6c5f3e7b4 Pidns: make full ... |
641 |
fl->fl_pid = pid_vnr(cfl->fl_nspid); |
ab1f16116 pid-namespaces-vs... |
642 |
} else |
129a84de2 locks: fix F_GETL... |
643 |
fl->fl_type = F_UNLCK; |
b89f43213 fs/locks.c: prepa... |
644 |
unlock_flocks(); |
6d34ac199 locks: make posix... |
645 |
return; |
1da177e4c Linux-2.6.12-rc2 |
646 |
} |
1da177e4c Linux-2.6.12-rc2 |
647 |
EXPORT_SYMBOL(posix_test_lock); |
b533184fc locks: clarify po... |
648 649 650 651 652 |
/* * Deadlock detection: * * We attempt to detect deadlocks that are due purely to posix file * locks. |
1da177e4c Linux-2.6.12-rc2 |
653 |
* |
b533184fc locks: clarify po... |
654 655 656 657 658 659 660 |
* We assume that a task can be waiting for at most one lock at a time. * So for any acquired lock, the process holding that lock may be * waiting on at most one other lock. That lock in turns may be held by * someone waiting for at most one other lock. Given a requested lock * caller_fl which is about to wait for a conflicting lock block_fl, we * follow this chain of waiters to ensure we are not about to create a * cycle. |
1da177e4c Linux-2.6.12-rc2 |
661 |
* |
b533184fc locks: clarify po... |
662 663 664 |
* Since we do this before we ever put a process to sleep on a lock, we * are ensured that there is never a cycle; that is what guarantees that * the while() loop in posix_locks_deadlock() eventually completes. |
97855b49b locks: fix possib... |
665 |
* |
b533184fc locks: clarify po... |
666 667 668 669 670 |
* Note: the above assumption may not be true when handling lock * requests from a broken NFS client. It may also fail in the presence * of tasks (such as posix threads) sharing the same open file table. * * To handle those cases, we just bail out after a few iterations. |
1da177e4c Linux-2.6.12-rc2 |
671 |
*/ |
97855b49b locks: fix possib... |
672 673 |
#define MAX_DEADLK_ITERATIONS 10 |
b533184fc locks: clarify po... |
674 675 676 677 678 679 680 681 682 683 684 |
/* Find a lock that the owner of the given block_fl is blocking on. */ static struct file_lock *what_owner_is_waiting_for(struct file_lock *block_fl) { struct file_lock *fl; list_for_each_entry(fl, &blocked_list, fl_link) { if (posix_same_owner(fl, block_fl)) return fl->fl_next; } return NULL; } |
b0904e147 [PATCH] fs/locks.... |
685 |
static int posix_locks_deadlock(struct file_lock *caller_fl, |
1da177e4c Linux-2.6.12-rc2 |
686 687 |
struct file_lock *block_fl) { |
97855b49b locks: fix possib... |
688 |
int i = 0; |
1da177e4c Linux-2.6.12-rc2 |
689 |
|
b533184fc locks: clarify po... |
690 691 692 693 694 |
while ((block_fl = what_owner_is_waiting_for(block_fl))) { if (i++ > MAX_DEADLK_ITERATIONS) return 0; if (posix_same_owner(caller_fl, block_fl)) return 1; |
1da177e4c Linux-2.6.12-rc2 |
695 696 697 |
} return 0; } |
1da177e4c Linux-2.6.12-rc2 |
698 |
/* Try to create a FLOCK lock on filp. We always insert new FLOCK locks |
02888f41e locks: fix flock_... |
699 |
* after any leases, but before any posix locks. |
f475ae957 VFS: Allow caller... |
700 701 702 703 |
* * Note that if called with an FL_EXISTS argument, the caller may determine * whether or not a lock was successfully freed by testing the return * value for -ENOENT. |
1da177e4c Linux-2.6.12-rc2 |
704 |
*/ |
993dfa877 [PATCH] fs/locks.... |
705 |
static int flock_lock_file(struct file *filp, struct file_lock *request) |
1da177e4c Linux-2.6.12-rc2 |
706 |
{ |
993dfa877 [PATCH] fs/locks.... |
707 |
struct file_lock *new_fl = NULL; |
1da177e4c Linux-2.6.12-rc2 |
708 |
struct file_lock **before; |
0f7fc9e4d [PATCH] VFS: chan... |
709 |
struct inode * inode = filp->f_path.dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
710 711 |
int error = 0; int found = 0; |
b89f43213 fs/locks.c: prepa... |
712 |
if (!(request->fl_flags & FL_ACCESS) && (request->fl_type != F_UNLCK)) { |
84d535ade Memory shortage c... |
713 |
new_fl = locks_alloc_lock(); |
b89f43213 fs/locks.c: prepa... |
714 715 |
if (!new_fl) return -ENOMEM; |
84d535ade Memory shortage c... |
716 |
} |
b89f43213 fs/locks.c: prepa... |
717 718 719 |
lock_flocks(); if (request->fl_flags & FL_ACCESS) goto find_conflict; |
1da177e4c Linux-2.6.12-rc2 |
720 721 722 723 724 725 726 727 |
for_each_lock(inode, before) { struct file_lock *fl = *before; if (IS_POSIX(fl)) break; if (IS_LEASE(fl)) continue; if (filp != fl->fl_file) continue; |
993dfa877 [PATCH] fs/locks.... |
728 |
if (request->fl_type == fl->fl_type) |
1da177e4c Linux-2.6.12-rc2 |
729 730 731 732 733 |
goto out; found = 1; locks_delete_lock(before); break; } |
1da177e4c Linux-2.6.12-rc2 |
734 |
|
f475ae957 VFS: Allow caller... |
735 736 737 |
if (request->fl_type == F_UNLCK) { if ((request->fl_flags & FL_EXISTS) && !found) error = -ENOENT; |
993dfa877 [PATCH] fs/locks.... |
738 |
goto out; |
f475ae957 VFS: Allow caller... |
739 |
} |
1da177e4c Linux-2.6.12-rc2 |
740 741 742 743 744 |
/* * If a higher-priority process was blocked on the old file lock, * give it the opportunity to lock the file. */ |
b89f43213 fs/locks.c: prepa... |
745 746 |
if (found) { unlock_flocks(); |
def01bc53 sched: Convert th... |
747 |
cond_resched(); |
b89f43213 fs/locks.c: prepa... |
748 749 |
lock_flocks(); } |
1da177e4c Linux-2.6.12-rc2 |
750 |
|
f07f18dd6 VFS: Add support ... |
751 |
find_conflict: |
1da177e4c Linux-2.6.12-rc2 |
752 753 754 755 756 757 |
for_each_lock(inode, before) { struct file_lock *fl = *before; if (IS_POSIX(fl)) break; if (IS_LEASE(fl)) continue; |
993dfa877 [PATCH] fs/locks.... |
758 |
if (!flock_locks_conflict(request, fl)) |
1da177e4c Linux-2.6.12-rc2 |
759 760 |
continue; error = -EAGAIN; |
bde74e4bc locks: add specia... |
761 762 763 764 |
if (!(request->fl_flags & FL_SLEEP)) goto out; error = FILE_LOCK_DEFERRED; locks_insert_block(fl, request); |
1da177e4c Linux-2.6.12-rc2 |
765 766 |
goto out; } |
f07f18dd6 VFS: Add support ... |
767 768 |
if (request->fl_flags & FL_ACCESS) goto out; |
993dfa877 [PATCH] fs/locks.... |
769 |
locks_copy_lock(new_fl, request); |
0e2f6db88 Leases can be hid... |
770 |
locks_insert_lock(before, new_fl); |
993dfa877 [PATCH] fs/locks.... |
771 |
new_fl = NULL; |
9cedc194a [PATCH] Return er... |
772 |
error = 0; |
1da177e4c Linux-2.6.12-rc2 |
773 774 |
out: |
b89f43213 fs/locks.c: prepa... |
775 |
unlock_flocks(); |
993dfa877 [PATCH] fs/locks.... |
776 777 |
if (new_fl) locks_free_lock(new_fl); |
1da177e4c Linux-2.6.12-rc2 |
778 779 |
return error; } |
150b39345 locks: allow {vfs... |
780 |
static int __posix_lock_file(struct inode *inode, struct file_lock *request, struct file_lock *conflock) |
1da177e4c Linux-2.6.12-rc2 |
781 782 |
{ struct file_lock *fl; |
39005d022 [PATCH] locks: do... |
783 784 |
struct file_lock *new_fl = NULL; struct file_lock *new_fl2 = NULL; |
1da177e4c Linux-2.6.12-rc2 |
785 786 787 788 789 790 791 792 |
struct file_lock *left = NULL; struct file_lock *right = NULL; struct file_lock **before; int error, added = 0; /* * We may need two file_lock structures for this operation, * so we get them in advance to avoid races. |
39005d022 [PATCH] locks: do... |
793 794 |
* * In some cases we can be sure, that no new locks will be needed |
1da177e4c Linux-2.6.12-rc2 |
795 |
*/ |
39005d022 [PATCH] locks: do... |
796 797 798 799 800 801 |
if (!(request->fl_flags & FL_ACCESS) && (request->fl_type != F_UNLCK || request->fl_start != 0 || request->fl_end != OFFSET_MAX)) { new_fl = locks_alloc_lock(); new_fl2 = locks_alloc_lock(); } |
1da177e4c Linux-2.6.12-rc2 |
802 |
|
b89f43213 fs/locks.c: prepa... |
803 |
lock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
804 805 |
if (request->fl_type != F_UNLCK) { for_each_lock(inode, before) { |
526985b9d locks: kill redun... |
806 |
fl = *before; |
1da177e4c Linux-2.6.12-rc2 |
807 808 809 810 |
if (!IS_POSIX(fl)) continue; if (!posix_locks_conflict(request, fl)) continue; |
5842add2f [PATCH] VFS,fs/lo... |
811 |
if (conflock) |
1a747ee0c locks: don't call... |
812 |
__locks_copy_lock(conflock, fl); |
1da177e4c Linux-2.6.12-rc2 |
813 814 815 816 817 818 |
error = -EAGAIN; if (!(request->fl_flags & FL_SLEEP)) goto out; error = -EDEADLK; if (posix_locks_deadlock(request, fl)) goto out; |
bde74e4bc locks: add specia... |
819 |
error = FILE_LOCK_DEFERRED; |
1da177e4c Linux-2.6.12-rc2 |
820 821 822 823 824 825 826 827 828 |
locks_insert_block(fl, request); goto out; } } /* If we're just looking for a conflict, we're done. */ error = 0; if (request->fl_flags & FL_ACCESS) goto out; |
1da177e4c Linux-2.6.12-rc2 |
829 |
/* |
1da177e4c Linux-2.6.12-rc2 |
830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 |
* Find the first old lock with the same owner as the new lock. */ before = &inode->i_flock; /* First skip locks owned by other processes. */ while ((fl = *before) && (!IS_POSIX(fl) || !posix_same_owner(request, fl))) { before = &fl->fl_next; } /* Process locks with this owner. */ while ((fl = *before) && posix_same_owner(request, fl)) { /* Detect adjacent or overlapping regions (if same lock type) */ if (request->fl_type == fl->fl_type) { |
449231d6d From: Olaf Kirch ... |
846 847 848 849 |
/* In all comparisons of start vs end, use * "start - 1" rather than "end + 1". If end * is OFFSET_MAX, end + 1 will become negative. */ |
1da177e4c Linux-2.6.12-rc2 |
850 851 852 853 854 |
if (fl->fl_end < request->fl_start - 1) goto next_lock; /* If the next lock in the list has entirely bigger * addresses than the new one, insert the lock here. */ |
449231d6d From: Olaf Kirch ... |
855 |
if (fl->fl_start - 1 > request->fl_end) |
1da177e4c Linux-2.6.12-rc2 |
856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 |
break; /* If we come here, the new and old lock are of the * same type and adjacent or overlapping. Make one * lock yielding from the lower start address of both * locks to the higher end address. */ if (fl->fl_start > request->fl_start) fl->fl_start = request->fl_start; else request->fl_start = fl->fl_start; if (fl->fl_end < request->fl_end) fl->fl_end = request->fl_end; else request->fl_end = fl->fl_end; if (added) { locks_delete_lock(before); continue; } request = fl; added = 1; } else { /* Processing for different lock types is a bit * more complex. */ if (fl->fl_end < request->fl_start) goto next_lock; if (fl->fl_start > request->fl_end) break; if (request->fl_type == F_UNLCK) added = 1; if (fl->fl_start < request->fl_start) left = fl; /* If the next lock in the list has a higher end * address than the new one, insert the new one here. */ if (fl->fl_end > request->fl_end) { right = fl; break; } if (fl->fl_start >= request->fl_start) { /* The new lock completely replaces an old * one (This may happen several times). */ if (added) { locks_delete_lock(before); continue; } /* Replace the old lock with the new one. * Wake up anybody waiting for the old one, * as the change in lock type might satisfy * their needs. */ locks_wake_up_blocks(fl); fl->fl_start = request->fl_start; fl->fl_end = request->fl_end; fl->fl_type = request->fl_type; |
47831f35b VFS: Fix __posix_... |
914 915 |
locks_release_private(fl); locks_copy_private(fl, request); |
1da177e4c Linux-2.6.12-rc2 |
916 917 918 919 920 921 922 923 924 |
request = fl; added = 1; } } /* Go on to next lock. */ next_lock: before = &fl->fl_next; } |
0d9a490ab [PATCH] locks: do... |
925 926 927 928 929 930 931 932 933 |
/* * The above code only modifies existing locks in case of * merging or replacing. If new lock(s) need to be inserted * all modifications are done bellow this, so it's safe yet to * bail out. */ error = -ENOLCK; /* "no luck" */ if (right && left == right && !new_fl2) goto out; |
1da177e4c Linux-2.6.12-rc2 |
934 935 |
error = 0; if (!added) { |
f475ae957 VFS: Allow caller... |
936 937 938 |
if (request->fl_type == F_UNLCK) { if (request->fl_flags & FL_EXISTS) error = -ENOENT; |
1da177e4c Linux-2.6.12-rc2 |
939 |
goto out; |
f475ae957 VFS: Allow caller... |
940 |
} |
0d9a490ab [PATCH] locks: do... |
941 942 943 944 945 |
if (!new_fl) { error = -ENOLCK; goto out; } |
1da177e4c Linux-2.6.12-rc2 |
946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 |
locks_copy_lock(new_fl, request); locks_insert_lock(before, new_fl); new_fl = NULL; } if (right) { if (left == right) { /* The new lock breaks the old one in two pieces, * so we have to use the second new lock. */ left = new_fl2; new_fl2 = NULL; locks_copy_lock(left, right); locks_insert_lock(before, left); } right->fl_start = request->fl_end + 1; locks_wake_up_blocks(right); } if (left) { left->fl_end = request->fl_start - 1; locks_wake_up_blocks(left); } out: |
b89f43213 fs/locks.c: prepa... |
968 |
unlock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
969 970 971 972 973 974 975 976 977 978 979 980 981 982 |
/* * Free any unused locks. */ if (new_fl) locks_free_lock(new_fl); if (new_fl2) locks_free_lock(new_fl2); return error; } /** * posix_lock_file - Apply a POSIX-style lock to a file * @filp: The file to apply the lock to * @fl: The lock to be applied |
150b39345 locks: allow {vfs... |
983 |
* @conflock: Place to return a copy of the conflicting lock, if found. |
1da177e4c Linux-2.6.12-rc2 |
984 985 986 987 |
* * Add a POSIX style lock to a file. * We merge adjacent & overlapping locks whenever possible. * POSIX locks are sorted by owner task, then by starting address |
f475ae957 VFS: Allow caller... |
988 989 990 991 |
* * Note that if called with an FL_EXISTS argument, the caller may determine * whether or not a lock was successfully freed by testing the return * value for -ENOENT. |
1da177e4c Linux-2.6.12-rc2 |
992 |
*/ |
150b39345 locks: allow {vfs... |
993 |
int posix_lock_file(struct file *filp, struct file_lock *fl, |
5842add2f [PATCH] VFS,fs/lo... |
994 995 |
struct file_lock *conflock) { |
150b39345 locks: allow {vfs... |
996 |
return __posix_lock_file(filp->f_path.dentry->d_inode, fl, conflock); |
1da177e4c Linux-2.6.12-rc2 |
997 |
} |
150b39345 locks: allow {vfs... |
998 |
EXPORT_SYMBOL(posix_lock_file); |
1da177e4c Linux-2.6.12-rc2 |
999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 |
/** * posix_lock_file_wait - Apply a POSIX-style lock to a file * @filp: The file to apply the lock to * @fl: The lock to be applied * * Add a POSIX style lock to a file. * We merge adjacent & overlapping locks whenever possible. * POSIX locks are sorted by owner task, then by starting address */ int posix_lock_file_wait(struct file *filp, struct file_lock *fl) { int error; might_sleep (); for (;;) { |
150b39345 locks: allow {vfs... |
1014 |
error = posix_lock_file(filp, fl, NULL); |
bde74e4bc locks: add specia... |
1015 |
if (error != FILE_LOCK_DEFERRED) |
1da177e4c Linux-2.6.12-rc2 |
1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 |
break; error = wait_event_interruptible(fl->fl_wait, !fl->fl_next); if (!error) continue; locks_delete_block(fl); break; } return error; } EXPORT_SYMBOL(posix_lock_file_wait); /** * locks_mandatory_locked - Check for an active lock * @inode: the file to check * * Searches the inode's list of locks to find any POSIX locks which conflict. * This function is called from locks_verify_locked() only. */ int locks_mandatory_locked(struct inode *inode) { fl_owner_t owner = current->files; struct file_lock *fl; /* * Search the lock list for this inode for any POSIX locks. */ |
b89f43213 fs/locks.c: prepa... |
1043 |
lock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
1044 1045 1046 1047 1048 1049 |
for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) { if (!IS_POSIX(fl)) continue; if (fl->fl_owner != owner) break; } |
b89f43213 fs/locks.c: prepa... |
1050 |
unlock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 |
return fl ? -EAGAIN : 0; } /** * locks_mandatory_area - Check for a conflicting lock * @read_write: %FLOCK_VERIFY_WRITE for exclusive access, %FLOCK_VERIFY_READ * for shared * @inode: the file to check * @filp: how the file was opened (if it was) * @offset: start of area to check * @count: length of area to check * * Searches the inode's list of locks to find any POSIX locks which conflict. * This function is called from rw_verify_area() and * locks_verify_truncate(). */ int locks_mandatory_area(int read_write, struct inode *inode, struct file *filp, loff_t offset, size_t count) { struct file_lock fl; int error; locks_init_lock(&fl); fl.fl_owner = current->files; fl.fl_pid = current->tgid; fl.fl_file = filp; fl.fl_flags = FL_POSIX | FL_ACCESS; if (filp && !(filp->f_flags & O_NONBLOCK)) fl.fl_flags |= FL_SLEEP; fl.fl_type = (read_write == FLOCK_VERIFY_WRITE) ? F_WRLCK : F_RDLCK; fl.fl_start = offset; fl.fl_end = offset + count - 1; for (;;) { |
150b39345 locks: allow {vfs... |
1086 |
error = __posix_lock_file(inode, &fl, NULL); |
bde74e4bc locks: add specia... |
1087 |
if (error != FILE_LOCK_DEFERRED) |
1da177e4c Linux-2.6.12-rc2 |
1088 1089 1090 1091 1092 1093 1094 |
break; error = wait_event_interruptible(fl.fl_wait, !fl.fl_next); if (!error) { /* * If we've been sleeping someone might have * changed the permissions behind our back. */ |
a16877ca9 Cleanup macros fo... |
1095 |
if (__mandatory_lock(inode)) |
1da177e4c Linux-2.6.12-rc2 |
1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 |
continue; } locks_delete_block(&fl); break; } return error; } EXPORT_SYMBOL(locks_mandatory_area); /* We already had a lease on this file; just change its type */ int lease_modify(struct file_lock **before, int arg) { struct file_lock *fl = *before; int error = assign_type(fl, arg); if (error) return error; locks_wake_up_blocks(fl); if (arg == F_UNLCK) locks_delete_lock(before); return 0; } EXPORT_SYMBOL(lease_modify); static void time_out_leases(struct inode *inode) { struct file_lock **before; struct file_lock *fl; before = &inode->i_flock; while ((fl = *before) && IS_LEASE(fl) && (fl->fl_type & F_INPROGRESS)) { if ((fl->fl_break_time == 0) || time_before(jiffies, fl->fl_break_time)) { before = &fl->fl_next; continue; } |
1da177e4c Linux-2.6.12-rc2 |
1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 |
lease_modify(before, fl->fl_type & ~F_INPROGRESS); if (fl == *before) /* lease_modify may have freed fl */ before = &fl->fl_next; } } /** * __break_lease - revoke all outstanding leases on file * @inode: the inode of the file to return * @mode: the open mode (read or write) * |
87250dd26 leases: minor bre... |
1147 1148 1149 |
* break_lease (inlined for speed) has checked there already is at least * some kind of lock (maybe a lease) on this file. Leases are broken on * a call to open() or truncate(). This function can sleep unless you |
1da177e4c Linux-2.6.12-rc2 |
1150 1151 1152 1153 1154 1155 1156 |
* specified %O_NONBLOCK to your open(). */ int __break_lease(struct inode *inode, unsigned int mode) { int error = 0, future; struct file_lock *new_fl, *flock; struct file_lock *fl; |
1da177e4c Linux-2.6.12-rc2 |
1157 1158 |
unsigned long break_time; int i_have_this_lease = 0; |
8737c9305 Switch may_open()... |
1159 |
int want_write = (mode & O_ACCMODE) != O_RDONLY; |
1da177e4c Linux-2.6.12-rc2 |
1160 |
|
8737c9305 Switch may_open()... |
1161 |
new_fl = lease_alloc(NULL, want_write ? F_WRLCK : F_RDLCK); |
1da177e4c Linux-2.6.12-rc2 |
1162 |
|
b89f43213 fs/locks.c: prepa... |
1163 |
lock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 |
time_out_leases(inode); flock = inode->i_flock; if ((flock == NULL) || !IS_LEASE(flock)) goto out; for (fl = flock; fl && IS_LEASE(fl); fl = fl->fl_next) if (fl->fl_owner == current->files) i_have_this_lease = 1; |
8737c9305 Switch may_open()... |
1174 |
if (want_write) { |
1da177e4c Linux-2.6.12-rc2 |
1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 |
/* If we want write access, we have to revoke any lease. */ future = F_UNLCK | F_INPROGRESS; } else if (flock->fl_type & F_INPROGRESS) { /* If the lease is already being broken, we just leave it */ future = flock->fl_type; } else if (flock->fl_type & F_WRLCK) { /* Downgrade the exclusive lease to a read-only lease. */ future = F_RDLCK | F_INPROGRESS; } else { /* the existing lease was read-only, so we can read too. */ goto out; } |
e32b8ee27 locks: clean up l... |
1187 1188 1189 |
if (IS_ERR(new_fl) && !i_have_this_lease && ((mode & O_NONBLOCK) == 0)) { error = PTR_ERR(new_fl); |
1da177e4c Linux-2.6.12-rc2 |
1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 |
goto out; } break_time = 0; if (lease_break_time > 0) { break_time = jiffies + lease_break_time * HZ; if (break_time == 0) break_time++; /* so that 0 means no break time */ } for (fl = flock; fl && IS_LEASE(fl); fl = fl->fl_next) { if (fl->fl_type != future) { fl->fl_type = future; fl->fl_break_time = break_time; /* lease must have lmops break callback */ fl->fl_lmops->fl_break(fl); } } if (i_have_this_lease || (mode & O_NONBLOCK)) { error = -EWOULDBLOCK; goto out; } restart: break_time = flock->fl_break_time; if (break_time != 0) { break_time -= jiffies; if (break_time == 0) break_time++; } |
4321e01e7 file locks: Use w... |
1221 |
locks_insert_block(flock, new_fl); |
b89f43213 fs/locks.c: prepa... |
1222 |
unlock_flocks(); |
4321e01e7 file locks: Use w... |
1223 1224 |
error = wait_event_interruptible_timeout(new_fl->fl_wait, !new_fl->fl_next, break_time); |
b89f43213 fs/locks.c: prepa... |
1225 |
lock_flocks(); |
4321e01e7 file locks: Use w... |
1226 |
__locks_delete_block(new_fl); |
1da177e4c Linux-2.6.12-rc2 |
1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 |
if (error >= 0) { if (error == 0) time_out_leases(inode); /* Wait for the next lease that has not been broken yet */ for (flock = inode->i_flock; flock && IS_LEASE(flock); flock = flock->fl_next) { if (flock->fl_type & F_INPROGRESS) goto restart; } error = 0; } out: |
b89f43213 fs/locks.c: prepa... |
1240 |
unlock_flocks(); |
e32b8ee27 locks: clean up l... |
1241 |
if (!IS_ERR(new_fl)) |
1da177e4c Linux-2.6.12-rc2 |
1242 1243 1244 1245 1246 1247 1248 |
locks_free_lock(new_fl); return error; } EXPORT_SYMBOL(__break_lease); /** |
a6b91919e fs: fix kernel-do... |
1249 |
* lease_get_mtime - get the last modified time of an inode |
1da177e4c Linux-2.6.12-rc2 |
1250 1251 1252 1253 1254 |
* @inode: the inode * @time: pointer to a timespec which will contain the last modified time * * This is to force NFS clients to flush their caches for files with * exclusive leases. The justification is that if someone has an |
a6b91919e fs: fix kernel-do... |
1255 |
* exclusive lease, then they could be modifying it. |
1da177e4c Linux-2.6.12-rc2 |
1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 |
*/ void lease_get_mtime(struct inode *inode, struct timespec *time) { struct file_lock *flock = inode->i_flock; if (flock && IS_LEASE(flock) && (flock->fl_type & F_WRLCK)) *time = current_fs_time(inode->i_sb); else *time = inode->i_mtime; } EXPORT_SYMBOL(lease_get_mtime); /** * fcntl_getlease - Enquire what lease is currently active * @filp: the file * * The value returned by this function will be one of * (if no lease break is pending): * * %F_RDLCK to indicate a shared lease is held. * * %F_WRLCK to indicate an exclusive lease is held. * * %F_UNLCK to indicate no lease is held. * * (if a lease break is pending): * * %F_RDLCK to indicate an exclusive lease needs to be * changed to a shared lease (or removed). * * %F_UNLCK to indicate the lease needs to be removed. * * XXX: sfr & willy disagree over whether F_INPROGRESS * should be returned to userspace. */ int fcntl_getlease(struct file *filp) { struct file_lock *fl; int type = F_UNLCK; |
b89f43213 fs/locks.c: prepa... |
1295 |
lock_flocks(); |
0f7fc9e4d [PATCH] VFS: chan... |
1296 1297 |
time_out_leases(filp->f_path.dentry->d_inode); for (fl = filp->f_path.dentry->d_inode->i_flock; fl && IS_LEASE(fl); |
1da177e4c Linux-2.6.12-rc2 |
1298 1299 1300 1301 1302 1303 |
fl = fl->fl_next) { if (fl->fl_file == filp) { type = fl->fl_type & ~F_INPROGRESS; break; } } |
b89f43213 fs/locks.c: prepa... |
1304 |
unlock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
1305 1306 1307 1308 |
return type; } /** |
0af1a4504 rename setlease t... |
1309 |
* generic_setlease - sets a lease on an open file |
1da177e4c Linux-2.6.12-rc2 |
1310 1311 1312 1313 1314 1315 1316 |
* @filp: file pointer * @arg: type of lease to obtain * @flp: input - file_lock to use, output - file_lock inserted * * The (input) flp->fl_lmops->fl_break function is required * by break_lease(). * |
b89f43213 fs/locks.c: prepa... |
1317 |
* Called with file_lock_lock held. |
1da177e4c Linux-2.6.12-rc2 |
1318 |
*/ |
0af1a4504 rename setlease t... |
1319 |
int generic_setlease(struct file *filp, long arg, struct file_lock **flp) |
1da177e4c Linux-2.6.12-rc2 |
1320 |
{ |
7eaae2828 [PATCH] coverity:... |
1321 |
struct file_lock *fl, **before, **my_before = NULL, *lease; |
0f7fc9e4d [PATCH] VFS: chan... |
1322 |
struct dentry *dentry = filp->f_path.dentry; |
1da177e4c Linux-2.6.12-rc2 |
1323 1324 |
struct inode *inode = dentry->d_inode; int error, rdlease_count = 0, wrlease_count = 0; |
096657b65 locks: fix leaks ... |
1325 1326 1327 |
lease = *flp; error = -EACCES; |
da9592ede CRED: Wrap task c... |
1328 |
if ((current_fsuid() != inode->i_uid) && !capable(CAP_LEASE)) |
096657b65 locks: fix leaks ... |
1329 1330 |
goto out; error = -EINVAL; |
6d5e8b05c locks: share more... |
1331 |
if (!S_ISREG(inode->i_mode)) |
096657b65 locks: fix leaks ... |
1332 |
goto out; |
6d5e8b05c locks: share more... |
1333 1334 |
error = security_file_lock(filp, arg); if (error) |
096657b65 locks: fix leaks ... |
1335 |
goto out; |
6d5e8b05c locks: share more... |
1336 |
|
1da177e4c Linux-2.6.12-rc2 |
1337 |
time_out_leases(inode); |
d2ab0b0c4 locks: convert an... |
1338 |
BUG_ON(!(*flp)->fl_lmops->fl_break); |
1da177e4c Linux-2.6.12-rc2 |
1339 |
|
288b2fd82 leases: when unlo... |
1340 1341 1342 1343 1344 |
if (arg != F_UNLCK) { error = -EAGAIN; if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0)) goto out; if ((arg == F_WRLCK) |
b7ab39f63 fs: dcache scale ... |
1345 |
&& ((dentry->d_count > 1) |
288b2fd82 leases: when unlo... |
1346 1347 |
|| (atomic_read(&inode->i_count) > 1))) goto out; |
288b2fd82 leases: when unlo... |
1348 |
} |
85c59580b locks: Fix potent... |
1349 |
|
1da177e4c Linux-2.6.12-rc2 |
1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 |
/* * At this point, we know that if there is an exclusive * lease on this file, then we hold it on this filp * (otherwise our open of this file would have blocked). * And if we are trying to acquire an exclusive lease, * then the file is not open by anyone (including us) * except for this filp. */ for (before = &inode->i_flock; ((fl = *before) != NULL) && IS_LEASE(fl); before = &fl->fl_next) { |
255c7cf81 locks: minor setl... |
1361 |
if (fl->fl_file == filp) |
1da177e4c Linux-2.6.12-rc2 |
1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 |
my_before = before; else if (fl->fl_type == (F_INPROGRESS | F_UNLCK)) /* * Someone is in the process of opening this * file for writing so we may not take an * exclusive lease on it. */ wrlease_count++; else rdlease_count++; } |
5fcc60c3a leases: fix a ret... |
1373 |
error = -EAGAIN; |
1da177e4c Linux-2.6.12-rc2 |
1374 1375 1376 1377 1378 1379 |
if ((arg == F_RDLCK && (wrlease_count > 0)) || (arg == F_WRLCK && ((rdlease_count + wrlease_count) > 0))) goto out; if (my_before != NULL) { error = lease->fl_lmops->fl_change(my_before, arg); |
51ee4b84f locks: let the ca... |
1380 1381 |
if (!error) *flp = *my_before; |
1da177e4c Linux-2.6.12-rc2 |
1382 1383 |
goto out; } |
1da177e4c Linux-2.6.12-rc2 |
1384 1385 1386 1387 1388 1389 |
if (arg == F_UNLCK) goto out; error = -EINVAL; if (!leases_enable) goto out; |
c5b1f0d92 locks/nfsd: alloc... |
1390 |
locks_insert_lock(before, lease); |
85c59580b locks: Fix potent... |
1391 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
1392 |
|
1da177e4c Linux-2.6.12-rc2 |
1393 1394 1395 |
out: return error; } |
0af1a4504 rename setlease t... |
1396 |
EXPORT_SYMBOL(generic_setlease); |
1da177e4c Linux-2.6.12-rc2 |
1397 |
|
b89f43213 fs/locks.c: prepa... |
1398 1399 1400 1401 1402 1403 1404 1405 1406 |
static int __vfs_setlease(struct file *filp, long arg, struct file_lock **lease) { if (filp->f_op && filp->f_op->setlease) return filp->f_op->setlease(filp, arg, lease); else return generic_setlease(filp, arg, lease); } /** |
a9933cea7 locks: rename lea... |
1407 |
* vfs_setlease - sets a lease on an open file |
1da177e4c Linux-2.6.12-rc2 |
1408 1409 1410 1411 1412 |
* @filp: file pointer * @arg: type of lease to obtain * @lease: file_lock to use * * Call this to establish a lease on the file. |
f9ffed26d locks: provide a ... |
1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 |
* The (*lease)->fl_lmops->fl_break operation must be set; if not, * break_lease will oops! * * This will call the filesystem's setlease file method, if * defined. Note that there is no getlease method; instead, the * filesystem setlease method should call back to setlease() to * add a lease to the inode's lease list, where fcntl_getlease() can * find it. Since fcntl_getlease() only reports whether the current * task holds a lease, a cluster filesystem need only do this for * leases held by processes on this node. * * There is also no break_lease method; filesystems that |
c9404c9c3 Fix misspelling o... |
1425 |
* handle their own leases should break leases themselves from the |
f9ffed26d locks: provide a ... |
1426 1427 1428 1429 1430 |
* filesystem's open, create, and (on truncate) setattr methods. * * Warning: the only current setlease methods exist only to disable * leases in certain cases. More vfs changes may be required to * allow a full filesystem lease implementation. |
1da177e4c Linux-2.6.12-rc2 |
1431 |
*/ |
a9933cea7 locks: rename lea... |
1432 |
int vfs_setlease(struct file *filp, long arg, struct file_lock **lease) |
1da177e4c Linux-2.6.12-rc2 |
1433 |
{ |
1da177e4c Linux-2.6.12-rc2 |
1434 |
int error; |
b89f43213 fs/locks.c: prepa... |
1435 1436 1437 |
lock_flocks(); error = __vfs_setlease(filp, arg, lease); unlock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
1438 1439 1440 |
return error; } |
a9933cea7 locks: rename lea... |
1441 |
EXPORT_SYMBOL_GPL(vfs_setlease); |
1da177e4c Linux-2.6.12-rc2 |
1442 |
|
0ceaf6c70 locks: prevent EN... |
1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 |
static int do_fcntl_delete_lease(struct file *filp) { struct file_lock fl, *flp = &fl; lease_init(filp, F_UNLCK, flp); return vfs_setlease(filp, F_UNLCK, &flp); } static int do_fcntl_add_lease(unsigned int fd, struct file *filp, long arg) |
1da177e4c Linux-2.6.12-rc2 |
1453 |
{ |
3df057ac9 locks: fix leak o... |
1454 |
struct file_lock *fl, *ret; |
f7347ce4e fasync: re-organi... |
1455 |
struct fasync_struct *new; |
1da177e4c Linux-2.6.12-rc2 |
1456 |
int error; |
c5b1f0d92 locks/nfsd: alloc... |
1457 1458 1459 |
fl = lease_alloc(filp, arg); if (IS_ERR(fl)) return PTR_ERR(fl); |
1da177e4c Linux-2.6.12-rc2 |
1460 |
|
f7347ce4e fasync: re-organi... |
1461 1462 1463 1464 1465 |
new = fasync_alloc(); if (!new) { locks_free_lock(fl); return -ENOMEM; } |
3df057ac9 locks: fix leak o... |
1466 |
ret = fl; |
b89f43213 fs/locks.c: prepa... |
1467 |
lock_flocks(); |
8896b93f4 locks: remove dea... |
1468 |
error = __vfs_setlease(filp, arg, &ret); |
51ee4b84f locks: let the ca... |
1469 1470 1471 1472 1473 |
if (error) { unlock_flocks(); locks_free_lock(fl); goto out_free_fasync; } |
3df057ac9 locks: fix leak o... |
1474 1475 |
if (ret != fl) locks_free_lock(fl); |
1da177e4c Linux-2.6.12-rc2 |
1476 |
|
f7347ce4e fasync: re-organi... |
1477 1478 1479 1480 1481 1482 |
/* * fasync_insert_entry() returns the old entry if any. * If there was no old entry, then it used 'new' and * inserted it into the fasync list. Clear new so that * we don't release it here. */ |
3df057ac9 locks: fix leak o... |
1483 |
if (!fasync_insert_entry(fd, filp, &ret->fl_fasync, new)) |
f7347ce4e fasync: re-organi... |
1484 |
new = NULL; |
8896b93f4 locks: remove dea... |
1485 |
error = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0); |
b89f43213 fs/locks.c: prepa... |
1486 |
unlock_flocks(); |
51ee4b84f locks: let the ca... |
1487 1488 |
out_free_fasync: |
f7347ce4e fasync: re-organi... |
1489 1490 |
if (new) fasync_free(new); |
1da177e4c Linux-2.6.12-rc2 |
1491 1492 1493 1494 |
return error; } /** |
0ceaf6c70 locks: prevent EN... |
1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 |
* fcntl_setlease - sets a lease on an open file * @fd: open file descriptor * @filp: file pointer * @arg: type of lease to obtain * * Call this fcntl to establish a lease on the file. * Note that you also need to call %F_SETSIG to * receive a signal when the lease is broken. */ int fcntl_setlease(unsigned int fd, struct file *filp, long arg) { if (arg == F_UNLCK) return do_fcntl_delete_lease(filp); return do_fcntl_add_lease(fd, filp, arg); } /** |
1da177e4c Linux-2.6.12-rc2 |
1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 |
* flock_lock_file_wait - Apply a FLOCK-style lock to a file * @filp: The file to apply the lock to * @fl: The lock to be applied * * Add a FLOCK style lock to a file. */ int flock_lock_file_wait(struct file *filp, struct file_lock *fl) { int error; might_sleep(); for (;;) { error = flock_lock_file(filp, fl); |
bde74e4bc locks: add specia... |
1524 |
if (error != FILE_LOCK_DEFERRED) |
1da177e4c Linux-2.6.12-rc2 |
1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 |
break; error = wait_event_interruptible(fl->fl_wait, !fl->fl_next); if (!error) continue; locks_delete_block(fl); break; } return error; } EXPORT_SYMBOL(flock_lock_file_wait); /** * sys_flock: - flock() system call. * @fd: the file descriptor to lock. * @cmd: the type of lock to apply. * * Apply a %FL_FLOCK style lock to an open file descriptor. * The @cmd can be one of * * %LOCK_SH -- a shared lock. * * %LOCK_EX -- an exclusive lock. * * %LOCK_UN -- remove an existing lock. * * %LOCK_MAND -- a `mandatory' flock. This exists to emulate Windows Share Modes. * * %LOCK_MAND can be combined with %LOCK_READ or %LOCK_WRITE to allow other * processes read and write access respectively. */ |
002c8976e [CVE-2009-0029] S... |
1557 |
SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd) |
1da177e4c Linux-2.6.12-rc2 |
1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 |
{ struct file *filp; struct file_lock *lock; int can_sleep, unlock; int error; error = -EBADF; filp = fget(fd); if (!filp) goto out; can_sleep = !(cmd & LOCK_NB); cmd &= ~LOCK_NB; unlock = (cmd == LOCK_UN); |
aeb5d7270 [PATCH] introduce... |
1572 1573 |
if (!unlock && !(cmd & LOCK_MAND) && !(filp->f_mode & (FMODE_READ|FMODE_WRITE))) |
1da177e4c Linux-2.6.12-rc2 |
1574 1575 1576 1577 1578 1579 1580 |
goto out_putf; error = flock_make_lock(filp, &lock, cmd); if (error) goto out_putf; if (can_sleep) lock->fl_flags |= FL_SLEEP; |
713c0ecdb security: fix sec... |
1581 |
error = security_file_lock(filp, lock->fl_type); |
1da177e4c Linux-2.6.12-rc2 |
1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 |
if (error) goto out_free; if (filp->f_op && filp->f_op->flock) error = filp->f_op->flock(filp, (can_sleep) ? F_SETLKW : F_SETLK, lock); else error = flock_lock_file_wait(filp, lock); out_free: |
993dfa877 [PATCH] fs/locks.... |
1593 |
locks_free_lock(lock); |
1da177e4c Linux-2.6.12-rc2 |
1594 1595 1596 1597 1598 1599 |
out_putf: fput(filp); out: return error; } |
3ee17abd1 locks: factor out... |
1600 1601 1602 |
/** * vfs_test_lock - test file byte range lock * @filp: The file to test lock for |
6924c5549 locks: fix vfs_te... |
1603 |
* @fl: The lock to test; also used to hold result |
3ee17abd1 locks: factor out... |
1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 |
* * Returns -ERRNO on failure. Indicates presence of conflicting lock by * setting conf->fl_type to something other than F_UNLCK. */ int vfs_test_lock(struct file *filp, struct file_lock *fl) { if (filp->f_op && filp->f_op->lock) return filp->f_op->lock(filp, F_GETLK, fl); posix_test_lock(filp, fl); return 0; } EXPORT_SYMBOL_GPL(vfs_test_lock); |
c2fa1b8a6 locks: create pos... |
1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 |
static int posix_lock_to_flock(struct flock *flock, struct file_lock *fl) { flock->l_pid = fl->fl_pid; #if BITS_PER_LONG == 32 /* * Make sure we can represent the posix lock via * legacy 32bit flock. */ if (fl->fl_start > OFFT_OFFSET_MAX) return -EOVERFLOW; if (fl->fl_end != OFFSET_MAX && fl->fl_end > OFFT_OFFSET_MAX) return -EOVERFLOW; #endif flock->l_start = fl->fl_start; flock->l_len = fl->fl_end == OFFSET_MAX ? 0 : fl->fl_end - fl->fl_start + 1; flock->l_whence = 0; |
129a84de2 locks: fix F_GETL... |
1633 |
flock->l_type = fl->fl_type; |
c2fa1b8a6 locks: create pos... |
1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 |
return 0; } #if BITS_PER_LONG == 32 static void posix_lock_to_flock64(struct flock64 *flock, struct file_lock *fl) { flock->l_pid = fl->fl_pid; flock->l_start = fl->fl_start; flock->l_len = fl->fl_end == OFFSET_MAX ? 0 : fl->fl_end - fl->fl_start + 1; flock->l_whence = 0; flock->l_type = fl->fl_type; } #endif |
1da177e4c Linux-2.6.12-rc2 |
1648 1649 1650 1651 1652 |
/* Report the first existing lock that would conflict with l. * This implements the F_GETLK command of fcntl(). */ int fcntl_getlk(struct file *filp, struct flock __user *l) { |
9d6a8c5c2 locks: give posix... |
1653 |
struct file_lock file_lock; |
1da177e4c Linux-2.6.12-rc2 |
1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 |
struct flock flock; int error; error = -EFAULT; if (copy_from_user(&flock, l, sizeof(flock))) goto out; error = -EINVAL; if ((flock.l_type != F_RDLCK) && (flock.l_type != F_WRLCK)) goto out; error = flock_to_posix_lock(filp, &file_lock, &flock); if (error) goto out; |
3ee17abd1 locks: factor out... |
1667 1668 1669 |
error = vfs_test_lock(filp, &file_lock); if (error) goto out; |
1da177e4c Linux-2.6.12-rc2 |
1670 |
|
9d6a8c5c2 locks: give posix... |
1671 1672 1673 |
flock.l_type = file_lock.fl_type; if (file_lock.fl_type != F_UNLCK) { error = posix_lock_to_flock(&flock, &file_lock); |
c2fa1b8a6 locks: create pos... |
1674 |
if (error) |
1da177e4c Linux-2.6.12-rc2 |
1675 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
1676 1677 1678 1679 1680 1681 1682 |
} error = -EFAULT; if (!copy_to_user(l, &flock, sizeof(flock))) error = 0; out: return error; } |
7723ec977 locks: factor out... |
1683 1684 1685 1686 1687 |
/** * vfs_lock_file - file byte range lock * @filp: The file to apply the lock to * @cmd: type of locking operation (F_SETLK, F_GETLK, etc.) * @fl: The lock to be applied |
150b39345 locks: allow {vfs... |
1688 1689 1690 1691 1692 1693 1694 1695 |
* @conf: Place to return a copy of the conflicting lock, if found. * * A caller that doesn't care about the conflicting lock may pass NULL * as the final argument. * * If the filesystem defines a private ->lock() method, then @conf will * be left unchanged; so a caller that cares should initialize it to * some acceptable default. |
2beb6614f locks: add fl_gra... |
1696 1697 1698 1699 1700 1701 1702 |
* * To avoid blocking kernel daemons, such as lockd, that need to acquire POSIX * locks, the ->lock() interface may return asynchronously, before the lock has * been granted or denied by the underlying filesystem, if (and only if) * fl_grant is set. Callers expecting ->lock() to return asynchronously * will only use F_SETLK, not F_SETLKW; they will set FL_SLEEP if (and only if) * the request is for a blocking lock. When ->lock() does return asynchronously, |
bde74e4bc locks: add specia... |
1703 |
* it must return FILE_LOCK_DEFERRED, and call ->fl_grant() when the lock |
2beb6614f locks: add fl_gra... |
1704 1705 |
* request completes. * If the request is for non-blocking lock the file system should return |
bde74e4bc locks: add specia... |
1706 1707 |
* FILE_LOCK_DEFERRED then try to get the lock and call the callback routine * with the result. If the request timed out the callback routine will return a |
2beb6614f locks: add fl_gra... |
1708 1709 1710 1711 1712 |
* nonzero return code and the file system should release the lock. The file * system is also responsible to keep a corresponding posix lock when it * grants a lock so the VFS can find out which locks are locally held and do * the correct lock cleanup when required. * The underlying filesystem must not drop the kernel lock or call |
bde74e4bc locks: add specia... |
1713 |
* ->fl_grant() before returning to the caller with a FILE_LOCK_DEFERRED |
2beb6614f locks: add fl_gra... |
1714 |
* return code. |
7723ec977 locks: factor out... |
1715 |
*/ |
150b39345 locks: allow {vfs... |
1716 |
int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl, struct file_lock *conf) |
7723ec977 locks: factor out... |
1717 1718 1719 1720 |
{ if (filp->f_op && filp->f_op->lock) return filp->f_op->lock(filp, cmd, fl); else |
150b39345 locks: allow {vfs... |
1721 |
return posix_lock_file(filp, fl, conf); |
7723ec977 locks: factor out... |
1722 1723 |
} EXPORT_SYMBOL_GPL(vfs_lock_file); |
b648a6de0 locks: cleanup co... |
1724 1725 1726 1727 1728 1729 1730 1731 |
static int do_lock_file_wait(struct file *filp, unsigned int cmd, struct file_lock *fl) { int error; error = security_file_lock(filp, fl->fl_type); if (error) return error; |
764c76b37 locks: allow ->lo... |
1732 1733 1734 |
for (;;) { error = vfs_lock_file(filp, cmd, fl, NULL); if (error != FILE_LOCK_DEFERRED) |
b648a6de0 locks: cleanup co... |
1735 |
break; |
764c76b37 locks: allow ->lo... |
1736 1737 1738 1739 1740 1741 |
error = wait_event_interruptible(fl->fl_wait, !fl->fl_next); if (!error) continue; locks_delete_block(fl); break; |
b648a6de0 locks: cleanup co... |
1742 1743 1744 1745 |
} return error; } |
1da177e4c Linux-2.6.12-rc2 |
1746 1747 1748 |
/* Apply the lock described by l to an open file descriptor. * This implements both the F_SETLK and F_SETLKW commands of fcntl(). */ |
c293621bb [PATCH] stale POS... |
1749 1750 |
int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, struct flock __user *l) |
1da177e4c Linux-2.6.12-rc2 |
1751 1752 1753 1754 |
{ struct file_lock *file_lock = locks_alloc_lock(); struct flock flock; struct inode *inode; |
0b2bac2f1 [PATCH] fix SMP o... |
1755 |
struct file *f; |
1da177e4c Linux-2.6.12-rc2 |
1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 |
int error; if (file_lock == NULL) return -ENOLCK; /* * This might block, so we do it before checking the inode. */ error = -EFAULT; if (copy_from_user(&flock, l, sizeof(flock))) goto out; |
0f7fc9e4d [PATCH] VFS: chan... |
1767 |
inode = filp->f_path.dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
1768 1769 1770 1771 |
/* Don't allow mandatory locks on files that may be memory mapped * and shared. */ |
a16877ca9 Cleanup macros fo... |
1772 |
if (mandatory_lock(inode) && mapping_writably_mapped(filp->f_mapping)) { |
1da177e4c Linux-2.6.12-rc2 |
1773 1774 1775 |
error = -EAGAIN; goto out; } |
c293621bb [PATCH] stale POS... |
1776 |
again: |
1da177e4c Linux-2.6.12-rc2 |
1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 |
error = flock_to_posix_lock(filp, file_lock, &flock); if (error) goto out; if (cmd == F_SETLKW) { file_lock->fl_flags |= FL_SLEEP; } error = -EBADF; switch (flock.l_type) { case F_RDLCK: if (!(filp->f_mode & FMODE_READ)) goto out; break; case F_WRLCK: if (!(filp->f_mode & FMODE_WRITE)) goto out; break; case F_UNLCK: break; default: error = -EINVAL; goto out; } |
b648a6de0 locks: cleanup co... |
1800 |
error = do_lock_file_wait(filp, cmd, file_lock); |
1da177e4c Linux-2.6.12-rc2 |
1801 |
|
c293621bb [PATCH] stale POS... |
1802 1803 1804 1805 |
/* * Attempt to detect a close/fcntl race and recover by * releasing the lock that was just acquired. */ |
0b2bac2f1 [PATCH] fix SMP o... |
1806 1807 1808 1809 1810 1811 1812 1813 1814 |
/* * we need that spin_lock here - it prevents reordering between * update of inode->i_flock and check for it done in close(). * rcu_read_lock() wouldn't do. */ spin_lock(¤t->files->file_lock); f = fcheck(fd); spin_unlock(¤t->files->file_lock); if (!error && f != filp && flock.l_type != F_UNLCK) { |
c293621bb [PATCH] stale POS... |
1815 1816 |
flock.l_type = F_UNLCK; goto again; |
1da177e4c Linux-2.6.12-rc2 |
1817 |
} |
c293621bb [PATCH] stale POS... |
1818 |
out: |
1da177e4c Linux-2.6.12-rc2 |
1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 |
locks_free_lock(file_lock); return error; } #if BITS_PER_LONG == 32 /* Report the first existing lock that would conflict with l. * This implements the F_GETLK command of fcntl(). */ int fcntl_getlk64(struct file *filp, struct flock64 __user *l) { |
9d6a8c5c2 locks: give posix... |
1829 |
struct file_lock file_lock; |
1da177e4c Linux-2.6.12-rc2 |
1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 |
struct flock64 flock; int error; error = -EFAULT; if (copy_from_user(&flock, l, sizeof(flock))) goto out; error = -EINVAL; if ((flock.l_type != F_RDLCK) && (flock.l_type != F_WRLCK)) goto out; error = flock64_to_posix_lock(filp, &file_lock, &flock); if (error) goto out; |
3ee17abd1 locks: factor out... |
1843 1844 1845 |
error = vfs_test_lock(filp, &file_lock); if (error) goto out; |
9d6a8c5c2 locks: give posix... |
1846 1847 1848 |
flock.l_type = file_lock.fl_type; if (file_lock.fl_type != F_UNLCK) posix_lock_to_flock64(&flock, &file_lock); |
1da177e4c Linux-2.6.12-rc2 |
1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 |
error = -EFAULT; if (!copy_to_user(l, &flock, sizeof(flock))) error = 0; out: return error; } /* Apply the lock described by l to an open file descriptor. * This implements both the F_SETLK and F_SETLKW commands of fcntl(). */ |
c293621bb [PATCH] stale POS... |
1860 1861 |
int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd, struct flock64 __user *l) |
1da177e4c Linux-2.6.12-rc2 |
1862 1863 1864 1865 |
{ struct file_lock *file_lock = locks_alloc_lock(); struct flock64 flock; struct inode *inode; |
0b2bac2f1 [PATCH] fix SMP o... |
1866 |
struct file *f; |
1da177e4c Linux-2.6.12-rc2 |
1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 |
int error; if (file_lock == NULL) return -ENOLCK; /* * This might block, so we do it before checking the inode. */ error = -EFAULT; if (copy_from_user(&flock, l, sizeof(flock))) goto out; |
0f7fc9e4d [PATCH] VFS: chan... |
1878 |
inode = filp->f_path.dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
1879 1880 1881 1882 |
/* Don't allow mandatory locks on files that may be memory mapped * and shared. */ |
a16877ca9 Cleanup macros fo... |
1883 |
if (mandatory_lock(inode) && mapping_writably_mapped(filp->f_mapping)) { |
1da177e4c Linux-2.6.12-rc2 |
1884 1885 1886 |
error = -EAGAIN; goto out; } |
c293621bb [PATCH] stale POS... |
1887 |
again: |
1da177e4c Linux-2.6.12-rc2 |
1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 |
error = flock64_to_posix_lock(filp, file_lock, &flock); if (error) goto out; if (cmd == F_SETLKW64) { file_lock->fl_flags |= FL_SLEEP; } error = -EBADF; switch (flock.l_type) { case F_RDLCK: if (!(filp->f_mode & FMODE_READ)) goto out; break; case F_WRLCK: if (!(filp->f_mode & FMODE_WRITE)) goto out; break; case F_UNLCK: break; default: error = -EINVAL; goto out; } |
b648a6de0 locks: cleanup co... |
1911 |
error = do_lock_file_wait(filp, cmd, file_lock); |
1da177e4c Linux-2.6.12-rc2 |
1912 |
|
c293621bb [PATCH] stale POS... |
1913 1914 1915 1916 |
/* * Attempt to detect a close/fcntl race and recover by * releasing the lock that was just acquired. */ |
0b2bac2f1 [PATCH] fix SMP o... |
1917 1918 1919 1920 |
spin_lock(¤t->files->file_lock); f = fcheck(fd); spin_unlock(¤t->files->file_lock); if (!error && f != filp && flock.l_type != F_UNLCK) { |
c293621bb [PATCH] stale POS... |
1921 1922 |
flock.l_type = F_UNLCK; goto again; |
1da177e4c Linux-2.6.12-rc2 |
1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 |
} out: locks_free_lock(file_lock); return error; } #endif /* BITS_PER_LONG == 32 */ /* * This function is called when the file is being removed * from the task's fd array. POSIX locks belonging to this task * are deleted at this time. */ void locks_remove_posix(struct file *filp, fl_owner_t owner) { |
ff7b86b82 [PATCH] locks: cl... |
1938 |
struct file_lock lock; |
1da177e4c Linux-2.6.12-rc2 |
1939 1940 1941 1942 1943 1944 |
/* * If there are no locks held on this file, we don't need to call * posix_lock_file(). Another process could be setting a lock on this * file at the same time, but we wouldn't remove that lock anyway. */ |
0f7fc9e4d [PATCH] VFS: chan... |
1945 |
if (!filp->f_path.dentry->d_inode->i_flock) |
1da177e4c Linux-2.6.12-rc2 |
1946 1947 1948 |
return; lock.fl_type = F_UNLCK; |
75e1fcc0b [PATCH] vfs: add ... |
1949 |
lock.fl_flags = FL_POSIX | FL_CLOSE; |
1da177e4c Linux-2.6.12-rc2 |
1950 1951 1952 1953 1954 1955 1956 |
lock.fl_start = 0; lock.fl_end = OFFSET_MAX; lock.fl_owner = owner; lock.fl_pid = current->tgid; lock.fl_file = filp; lock.fl_ops = NULL; lock.fl_lmops = NULL; |
150b39345 locks: allow {vfs... |
1957 |
vfs_lock_file(filp, F_SETLK, &lock, NULL); |
1da177e4c Linux-2.6.12-rc2 |
1958 |
|
1da177e4c Linux-2.6.12-rc2 |
1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 |
if (lock.fl_ops && lock.fl_ops->fl_release_private) lock.fl_ops->fl_release_private(&lock); } EXPORT_SYMBOL(locks_remove_posix); /* * This function is called on the last close of an open file. */ void locks_remove_flock(struct file *filp) { |
0f7fc9e4d [PATCH] VFS: chan... |
1970 |
struct inode * inode = filp->f_path.dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 |
struct file_lock *fl; struct file_lock **before; if (!inode->i_flock) return; if (filp->f_op && filp->f_op->flock) { struct file_lock fl = { .fl_pid = current->tgid, .fl_file = filp, .fl_flags = FL_FLOCK, .fl_type = F_UNLCK, .fl_end = OFFSET_MAX, }; filp->f_op->flock(filp, F_SETLKW, &fl); |
80fec4c62 [PATCH] VFS: Ensu... |
1986 1987 |
if (fl.fl_ops && fl.fl_ops->fl_release_private) fl.fl_ops->fl_release_private(&fl); |
1da177e4c Linux-2.6.12-rc2 |
1988 |
} |
b89f43213 fs/locks.c: prepa... |
1989 |
lock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
1990 1991 1992 1993 |
before = &inode->i_flock; while ((fl = *before) != NULL) { if (fl->fl_file == filp) { |
c293621bb [PATCH] stale POS... |
1994 |
if (IS_FLOCK(fl)) { |
1da177e4c Linux-2.6.12-rc2 |
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 |
locks_delete_lock(before); continue; } if (IS_LEASE(fl)) { lease_modify(before, F_UNLCK); continue; } /* What? */ BUG(); } before = &fl->fl_next; } |
b89f43213 fs/locks.c: prepa... |
2007 |
unlock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
2008 2009 2010 |
} /** |
1da177e4c Linux-2.6.12-rc2 |
2011 2012 2013 2014 2015 2016 |
* posix_unblock_lock - stop waiting for a file lock * @filp: how the file was opened * @waiter: the lock which was waiting * * lockd needs to block waiting for locks. */ |
64a318ee2 NLM: Further canc... |
2017 |
int |
1da177e4c Linux-2.6.12-rc2 |
2018 2019 |
posix_unblock_lock(struct file *filp, struct file_lock *waiter) { |
64a318ee2 NLM: Further canc... |
2020 |
int status = 0; |
b89f43213 fs/locks.c: prepa... |
2021 |
lock_flocks(); |
5996a298d NLM: don't unlock... |
2022 |
if (waiter->fl_next) |
1da177e4c Linux-2.6.12-rc2 |
2023 |
__locks_delete_block(waiter); |
64a318ee2 NLM: Further canc... |
2024 2025 |
else status = -ENOENT; |
b89f43213 fs/locks.c: prepa... |
2026 |
unlock_flocks(); |
64a318ee2 NLM: Further canc... |
2027 |
return status; |
1da177e4c Linux-2.6.12-rc2 |
2028 2029 2030 |
} EXPORT_SYMBOL(posix_unblock_lock); |
9b9d2ab41 locks: add lock c... |
2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 |
/** * vfs_cancel_lock - file byte range unblock lock * @filp: The file to apply the unblock to * @fl: The lock to be unblocked * * Used by lock managers to cancel blocked requests */ int vfs_cancel_lock(struct file *filp, struct file_lock *fl) { if (filp->f_op && filp->f_op->lock) return filp->f_op->lock(filp, F_CANCELLK, fl); return 0; } EXPORT_SYMBOL_GPL(vfs_cancel_lock); |
7f8ada98d Rework /proc/lock... |
2046 |
#ifdef CONFIG_PROC_FS |
d8ba7a363 proc: move rest o... |
2047 |
#include <linux/proc_fs.h> |
7f8ada98d Rework /proc/lock... |
2048 2049 2050 |
#include <linux/seq_file.h> static void lock_get_status(struct seq_file *f, struct file_lock *fl, |
99dc82925 procfs: fix numbe... |
2051 |
loff_t id, char *pfx) |
1da177e4c Linux-2.6.12-rc2 |
2052 2053 |
{ struct inode *inode = NULL; |
ab1f16116 pid-namespaces-vs... |
2054 2055 2056 |
unsigned int fl_pid; if (fl->fl_nspid) |
6c5f3e7b4 Pidns: make full ... |
2057 |
fl_pid = pid_vnr(fl->fl_nspid); |
ab1f16116 pid-namespaces-vs... |
2058 2059 |
else fl_pid = fl->fl_pid; |
1da177e4c Linux-2.6.12-rc2 |
2060 2061 |
if (fl->fl_file != NULL) |
0f7fc9e4d [PATCH] VFS: chan... |
2062 |
inode = fl->fl_file->f_path.dentry->d_inode; |
1da177e4c Linux-2.6.12-rc2 |
2063 |
|
99dc82925 procfs: fix numbe... |
2064 |
seq_printf(f, "%lld:%s ", id, pfx); |
1da177e4c Linux-2.6.12-rc2 |
2065 |
if (IS_POSIX(fl)) { |
7f8ada98d Rework /proc/lock... |
2066 |
seq_printf(f, "%6s %s ", |
1da177e4c Linux-2.6.12-rc2 |
2067 2068 |
(fl->fl_flags & FL_ACCESS) ? "ACCESS" : "POSIX ", (inode == NULL) ? "*NOINODE*" : |
a16877ca9 Cleanup macros fo... |
2069 |
mandatory_lock(inode) ? "MANDATORY" : "ADVISORY "); |
1da177e4c Linux-2.6.12-rc2 |
2070 2071 |
} else if (IS_FLOCK(fl)) { if (fl->fl_type & LOCK_MAND) { |
7f8ada98d Rework /proc/lock... |
2072 |
seq_printf(f, "FLOCK MSNFS "); |
1da177e4c Linux-2.6.12-rc2 |
2073 |
} else { |
7f8ada98d Rework /proc/lock... |
2074 |
seq_printf(f, "FLOCK ADVISORY "); |
1da177e4c Linux-2.6.12-rc2 |
2075 2076 |
} } else if (IS_LEASE(fl)) { |
7f8ada98d Rework /proc/lock... |
2077 |
seq_printf(f, "LEASE "); |
1da177e4c Linux-2.6.12-rc2 |
2078 |
if (fl->fl_type & F_INPROGRESS) |
7f8ada98d Rework /proc/lock... |
2079 |
seq_printf(f, "BREAKING "); |
1da177e4c Linux-2.6.12-rc2 |
2080 |
else if (fl->fl_file) |
7f8ada98d Rework /proc/lock... |
2081 |
seq_printf(f, "ACTIVE "); |
1da177e4c Linux-2.6.12-rc2 |
2082 |
else |
7f8ada98d Rework /proc/lock... |
2083 |
seq_printf(f, "BREAKER "); |
1da177e4c Linux-2.6.12-rc2 |
2084 |
} else { |
7f8ada98d Rework /proc/lock... |
2085 |
seq_printf(f, "UNKNOWN UNKNOWN "); |
1da177e4c Linux-2.6.12-rc2 |
2086 2087 |
} if (fl->fl_type & LOCK_MAND) { |
7f8ada98d Rework /proc/lock... |
2088 |
seq_printf(f, "%s ", |
1da177e4c Linux-2.6.12-rc2 |
2089 2090 2091 2092 |
(fl->fl_type & LOCK_READ) ? (fl->fl_type & LOCK_WRITE) ? "RW " : "READ " : (fl->fl_type & LOCK_WRITE) ? "WRITE" : "NONE "); } else { |
7f8ada98d Rework /proc/lock... |
2093 |
seq_printf(f, "%s ", |
1da177e4c Linux-2.6.12-rc2 |
2094 2095 2096 2097 2098 2099 |
(fl->fl_type & F_INPROGRESS) ? (fl->fl_type & F_UNLCK) ? "UNLCK" : "READ " : (fl->fl_type & F_WRLCK) ? "WRITE" : "READ "); } if (inode) { #ifdef WE_CAN_BREAK_LSLK_NOW |
ab1f16116 pid-namespaces-vs... |
2100 |
seq_printf(f, "%d %s:%ld ", fl_pid, |
1da177e4c Linux-2.6.12-rc2 |
2101 2102 2103 |
inode->i_sb->s_id, inode->i_ino); #else /* userspace relies on this representation of dev_t ;-( */ |
ab1f16116 pid-namespaces-vs... |
2104 |
seq_printf(f, "%d %02x:%02x:%ld ", fl_pid, |
1da177e4c Linux-2.6.12-rc2 |
2105 2106 2107 2108 |
MAJOR(inode->i_sb->s_dev), MINOR(inode->i_sb->s_dev), inode->i_ino); #endif } else { |
ab1f16116 pid-namespaces-vs... |
2109 |
seq_printf(f, "%d <none>:0 ", fl_pid); |
1da177e4c Linux-2.6.12-rc2 |
2110 2111 2112 |
} if (IS_POSIX(fl)) { if (fl->fl_end == OFFSET_MAX) |
7f8ada98d Rework /proc/lock... |
2113 2114 |
seq_printf(f, "%Ld EOF ", fl->fl_start); |
1da177e4c Linux-2.6.12-rc2 |
2115 |
else |
7f8ada98d Rework /proc/lock... |
2116 2117 |
seq_printf(f, "%Ld %Ld ", fl->fl_start, fl->fl_end); |
1da177e4c Linux-2.6.12-rc2 |
2118 |
} else { |
7f8ada98d Rework /proc/lock... |
2119 2120 |
seq_printf(f, "0 EOF "); |
1da177e4c Linux-2.6.12-rc2 |
2121 2122 |
} } |
7f8ada98d Rework /proc/lock... |
2123 |
static int locks_show(struct seq_file *f, void *v) |
1da177e4c Linux-2.6.12-rc2 |
2124 |
{ |
7f8ada98d Rework /proc/lock... |
2125 |
struct file_lock *fl, *bfl; |
1da177e4c Linux-2.6.12-rc2 |
2126 |
|
7f8ada98d Rework /proc/lock... |
2127 |
fl = list_entry(v, struct file_lock, fl_link); |
1da177e4c Linux-2.6.12-rc2 |
2128 |
|
99dc82925 procfs: fix numbe... |
2129 |
lock_get_status(f, fl, *((loff_t *)f->private), ""); |
1da177e4c Linux-2.6.12-rc2 |
2130 |
|
7f8ada98d Rework /proc/lock... |
2131 |
list_for_each_entry(bfl, &fl->fl_block, fl_block) |
99dc82925 procfs: fix numbe... |
2132 |
lock_get_status(f, bfl, *((loff_t *)f->private), " ->"); |
094f28252 fs/locks.c: use l... |
2133 |
|
7f8ada98d Rework /proc/lock... |
2134 2135 |
return 0; } |
1da177e4c Linux-2.6.12-rc2 |
2136 |
|
7f8ada98d Rework /proc/lock... |
2137 2138 |
static void *locks_start(struct seq_file *f, loff_t *pos) { |
99dc82925 procfs: fix numbe... |
2139 |
loff_t *p = f->private; |
b89f43213 fs/locks.c: prepa... |
2140 |
lock_flocks(); |
99dc82925 procfs: fix numbe... |
2141 |
*p = (*pos + 1); |
7f8ada98d Rework /proc/lock... |
2142 2143 |
return seq_list_start(&file_lock_list, *pos); } |
1da177e4c Linux-2.6.12-rc2 |
2144 |
|
7f8ada98d Rework /proc/lock... |
2145 2146 |
static void *locks_next(struct seq_file *f, void *v, loff_t *pos) { |
99dc82925 procfs: fix numbe... |
2147 2148 |
loff_t *p = f->private; ++*p; |
7f8ada98d Rework /proc/lock... |
2149 2150 |
return seq_list_next(v, &file_lock_list, pos); } |
1da177e4c Linux-2.6.12-rc2 |
2151 |
|
7f8ada98d Rework /proc/lock... |
2152 2153 |
static void locks_stop(struct seq_file *f, void *v) { |
b89f43213 fs/locks.c: prepa... |
2154 |
unlock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
2155 |
} |
d8ba7a363 proc: move rest o... |
2156 |
static const struct seq_operations locks_seq_operations = { |
7f8ada98d Rework /proc/lock... |
2157 2158 2159 2160 2161 |
.start = locks_start, .next = locks_next, .stop = locks_stop, .show = locks_show, }; |
d8ba7a363 proc: move rest o... |
2162 2163 2164 |
static int locks_open(struct inode *inode, struct file *filp) { |
99dc82925 procfs: fix numbe... |
2165 |
return seq_open_private(filp, &locks_seq_operations, sizeof(loff_t)); |
d8ba7a363 proc: move rest o... |
2166 2167 2168 2169 2170 2171 |
} static const struct file_operations proc_locks_operations = { .open = locks_open, .read = seq_read, .llseek = seq_lseek, |
99dc82925 procfs: fix numbe... |
2172 |
.release = seq_release_private, |
d8ba7a363 proc: move rest o... |
2173 2174 2175 2176 2177 2178 2179 2180 |
}; static int __init proc_locks_init(void) { proc_create("locks", 0, NULL, &proc_locks_operations); return 0; } module_init(proc_locks_init); |
7f8ada98d Rework /proc/lock... |
2181 |
#endif |
1da177e4c Linux-2.6.12-rc2 |
2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 |
/** * lock_may_read - checks that the region is free of locks * @inode: the inode that is being read * @start: the first byte to read * @len: the number of bytes to read * * Emulates Windows locking requirements. Whole-file * mandatory locks (share modes) can prohibit a read and * byte-range POSIX locks can prohibit a read if they overlap. * * N.B. this function is only ever called * from knfsd and ownership of locks is never checked. */ int lock_may_read(struct inode *inode, loff_t start, unsigned long len) { struct file_lock *fl; int result = 1; |
b89f43213 fs/locks.c: prepa... |
2199 |
lock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 |
for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) { if (IS_POSIX(fl)) { if (fl->fl_type == F_RDLCK) continue; if ((fl->fl_end < start) || (fl->fl_start > (start + len))) continue; } else if (IS_FLOCK(fl)) { if (!(fl->fl_type & LOCK_MAND)) continue; if (fl->fl_type & LOCK_READ) continue; } else continue; result = 0; break; } |
b89f43213 fs/locks.c: prepa... |
2216 |
unlock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 |
return result; } EXPORT_SYMBOL(lock_may_read); /** * lock_may_write - checks that the region is free of locks * @inode: the inode that is being written * @start: the first byte to write * @len: the number of bytes to write * * Emulates Windows locking requirements. Whole-file * mandatory locks (share modes) can prohibit a write and * byte-range POSIX locks can prohibit a write if they overlap. * * N.B. this function is only ever called * from knfsd and ownership of locks is never checked. */ int lock_may_write(struct inode *inode, loff_t start, unsigned long len) { struct file_lock *fl; int result = 1; |
b89f43213 fs/locks.c: prepa... |
2239 |
lock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 |
for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) { if (IS_POSIX(fl)) { if ((fl->fl_end < start) || (fl->fl_start > (start + len))) continue; } else if (IS_FLOCK(fl)) { if (!(fl->fl_type & LOCK_MAND)) continue; if (fl->fl_type & LOCK_WRITE) continue; } else continue; result = 0; break; } |
b89f43213 fs/locks.c: prepa... |
2254 |
unlock_flocks(); |
1da177e4c Linux-2.6.12-rc2 |
2255 2256 2257 2258 |
return result; } EXPORT_SYMBOL(lock_may_write); |
1da177e4c Linux-2.6.12-rc2 |
2259 2260 2261 2262 |
static int __init filelock_init(void) { filelock_cache = kmem_cache_create("file_lock_cache", sizeof(struct file_lock), 0, SLAB_PANIC, |
20c2df83d mm: Remove slab d... |
2263 |
init_once); |
1da177e4c Linux-2.6.12-rc2 |
2264 2265 2266 2267 |
return 0; } core_initcall(filelock_init); |