diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-03-25 03:53:42 -0300 |
---|---|---|
committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-03-25 03:53:42 -0300 |
commit | 03dd4cb26d967f9588437b0fc9cc0e8353322bb7 (patch) | |
tree | fa581f6dc1c0596391690d1f67eceef3af8246dc /fs/locks.c | |
parent | d4e493caf788ef44982e131ff9c786546904d934 (diff) |
Linux-libre 4.5-gnu
Diffstat (limited to 'fs/locks.c')
-rw-r--r-- | fs/locks.c | 119 |
1 files changed, 76 insertions, 43 deletions
diff --git a/fs/locks.c b/fs/locks.c index 6333263b7..7c5f91be9 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -119,7 +119,6 @@ #include <linux/fdtable.h> #include <linux/fs.h> #include <linux/init.h> -#include <linux/module.h> #include <linux/security.h> #include <linux/slab.h> #include <linux/syscalls.h> @@ -230,16 +229,44 @@ locks_get_lock_context(struct inode *inode, int type) ctx = smp_load_acquire(&inode->i_flctx); } out: + trace_locks_get_lock_context(inode, type, ctx); return ctx; } +static void +locks_dump_ctx_list(struct list_head *list, char *list_type) +{ + struct file_lock *fl; + + list_for_each_entry(fl, list, fl_list) { + pr_warn("%s: fl_owner=%p fl_flags=0x%x fl_type=0x%x fl_pid=%u\n", list_type, fl->fl_owner, fl->fl_flags, fl->fl_type, fl->fl_pid); + } +} + +static void +locks_check_ctx_lists(struct inode *inode) +{ + struct file_lock_context *ctx = inode->i_flctx; + + if (unlikely(!list_empty(&ctx->flc_flock) || + !list_empty(&ctx->flc_posix) || + !list_empty(&ctx->flc_lease))) { + pr_warn("Leaked locks on dev=0x%x:0x%x ino=0x%lx:\n", + MAJOR(inode->i_sb->s_dev), MINOR(inode->i_sb->s_dev), + inode->i_ino); + locks_dump_ctx_list(&ctx->flc_flock, "FLOCK"); + locks_dump_ctx_list(&ctx->flc_posix, "POSIX"); + locks_dump_ctx_list(&ctx->flc_lease, "LEASE"); + } +} + void -locks_free_lock_context(struct file_lock_context *ctx) +locks_free_lock_context(struct inode *inode) { - if (ctx) { - WARN_ON_ONCE(!list_empty(&ctx->flc_flock)); - WARN_ON_ONCE(!list_empty(&ctx->flc_posix)); - WARN_ON_ONCE(!list_empty(&ctx->flc_lease)); + struct file_lock_context *ctx = inode->i_flctx; + + if (unlikely(ctx)) { + locks_check_ctx_lists(inode); kmem_cache_free(flctx_cache, ctx); } } @@ -934,7 +961,8 @@ out: return error; } -static int __posix_lock_file(struct inode *inode, struct file_lock *request, struct file_lock *conflock) +static int posix_lock_inode(struct inode *inode, struct file_lock *request, + struct file_lock *conflock) { struct file_lock *fl, *tmp; struct file_lock *new_fl = NULL; @@ -1142,6 +1170,8 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str if (new_fl2) locks_free_lock(new_fl2); locks_dispose_list(&dispose); + trace_posix_lock_inode(inode, request, error); + return error; } @@ -1162,7 +1192,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str int posix_lock_file(struct file *filp, struct file_lock *fl, struct file_lock *conflock) { - return __posix_lock_file(file_inode(filp), fl, conflock); + return posix_lock_inode(file_inode(filp), fl, conflock); } EXPORT_SYMBOL(posix_lock_file); @@ -1178,7 +1208,7 @@ static int posix_lock_inode_wait(struct inode *inode, struct file_lock *fl) int error; might_sleep (); for (;;) { - error = __posix_lock_file(inode, fl, NULL); + error = posix_lock_inode(inode, fl, NULL); if (error != FILE_LOCK_DEFERRED) break; error = wait_event_interruptible(fl->fl_wait, !fl->fl_next); @@ -1191,6 +1221,7 @@ static int posix_lock_inode_wait(struct inode *inode, struct file_lock *fl) return error; } +#ifdef CONFIG_MANDATORY_FILE_LOCKING /** * locks_mandatory_locked - Check for an active lock * @file: the file to check @@ -1227,20 +1258,16 @@ int locks_mandatory_locked(struct file *file) /** * 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 + * @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 + * @start: first byte in the file to check + * @end: lastbyte in the file to check + * @type: %F_WRLCK for a write lock, else %F_RDLCK * * 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) +int locks_mandatory_area(struct inode *inode, struct file *filp, loff_t start, + loff_t end, unsigned char type) { struct file_lock fl; int error; @@ -1252,15 +1279,15 @@ int locks_mandatory_area(int read_write, struct inode *inode, fl.fl_flags = FL_POSIX | FL_ACCESS; if (filp && !(filp->f_flags & O_NONBLOCK)) sleep = true; - fl.fl_type = (read_write == FLOCK_VERIFY_WRITE) ? F_WRLCK : F_RDLCK; - fl.fl_start = offset; - fl.fl_end = offset + count - 1; + fl.fl_type = type; + fl.fl_start = start; + fl.fl_end = end; for (;;) { if (filp) { fl.fl_owner = filp; fl.fl_flags &= ~FL_SLEEP; - error = __posix_lock_file(inode, &fl, NULL); + error = posix_lock_inode(inode, &fl, NULL); if (!error) break; } @@ -1268,7 +1295,7 @@ int locks_mandatory_area(int read_write, struct inode *inode, if (sleep) fl.fl_flags |= FL_SLEEP; fl.fl_owner = current->files; - error = __posix_lock_file(inode, &fl, NULL); + error = posix_lock_inode(inode, &fl, NULL); if (error != FILE_LOCK_DEFERRED) break; error = wait_event_interruptible(fl.fl_wait, !fl.fl_next); @@ -1289,6 +1316,7 @@ int locks_mandatory_area(int read_write, struct inode *inode, } EXPORT_SYMBOL(locks_mandatory_area); +#endif /* CONFIG_MANDATORY_FILE_LOCKING */ static void lease_clear_pending(struct file_lock *fl, int arg) { @@ -1503,12 +1531,10 @@ void lease_get_mtime(struct inode *inode, struct timespec *time) ctx = smp_load_acquire(&inode->i_flctx); if (ctx && !list_empty_careful(&ctx->flc_lease)) { spin_lock(&ctx->flc_lock); - if (!list_empty(&ctx->flc_lease)) { - fl = list_first_entry(&ctx->flc_lease, - struct file_lock, fl_list); - if (fl->fl_type == F_WRLCK) - has_lease = true; - } + fl = list_first_entry_or_null(&ctx->flc_lease, + struct file_lock, fl_list); + if (fl && (fl->fl_type == F_WRLCK)) + has_lease = true; spin_unlock(&ctx->flc_lock); } @@ -1624,12 +1650,12 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr * bother, maybe that's a sign this just isn't a good file to * hand out a delegation on. */ - if (is_deleg && !mutex_trylock(&inode->i_mutex)) + if (is_deleg && !inode_trylock(inode)) return -EAGAIN; if (is_deleg && arg == F_WRLCK) { /* Write delegations are not currently supported: */ - mutex_unlock(&inode->i_mutex); + inode_unlock(inode); WARN_ON_ONCE(1); return -EINVAL; } @@ -1706,7 +1732,7 @@ out: spin_unlock(&ctx->flc_lock); locks_dispose_list(&dispose); if (is_deleg) - mutex_unlock(&inode->i_mutex); + inode_unlock(inode); if (!error && !my_fl) *flp = NULL; return error; @@ -2165,6 +2191,8 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, if (file_lock == NULL) return -ENOLCK; + inode = file_inode(filp); + /* * This might block, so we do it before checking the inode. */ @@ -2172,8 +2200,6 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, if (copy_from_user(&flock, l, sizeof(flock))) goto out; - inode = file_inode(filp); - /* Don't allow mandatory locks on files that may be memory mapped * and shared. */ @@ -2220,10 +2246,12 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, error = do_lock_file_wait(filp, cmd, file_lock); /* - * Attempt to detect a close/fcntl race and recover by - * releasing the lock that was just acquired. + * Attempt to detect a close/fcntl race and recover by releasing the + * lock that was just acquired. There is no need to do that when we're + * unlocking though, or for OFD locks. */ - if (!error && file_lock->fl_type != F_UNLCK) { + if (!error && file_lock->fl_type != F_UNLCK && + !(file_lock->fl_flags & FL_OFDLCK)) { /* * We need that spin_lock here - it prevents reordering between * update of i_flctx->flc_posix and check for it done in @@ -2240,6 +2268,7 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, } } out: + trace_fcntl_setlk(inode, file_lock, error); locks_free_lock(file_lock); return error; } @@ -2362,10 +2391,12 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd, error = do_lock_file_wait(filp, cmd, file_lock); /* - * Attempt to detect a close/fcntl race and recover by - * releasing the lock that was just acquired. + * Attempt to detect a close/fcntl race and recover by releasing the + * lock that was just acquired. There is no need to do that when we're + * unlocking though, or for OFD locks. */ - if (!error && file_lock->fl_type != F_UNLCK) { + if (!error && file_lock->fl_type != F_UNLCK && + !(file_lock->fl_flags & FL_OFDLCK)) { /* * We need that spin_lock here - it prevents reordering between * update of i_flctx->flc_posix and check for it done in @@ -2394,6 +2425,7 @@ out: */ void locks_remove_posix(struct file *filp, fl_owner_t owner) { + int error; struct file_lock lock; struct file_lock_context *ctx; @@ -2416,10 +2448,11 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner) lock.fl_ops = NULL; lock.fl_lmops = NULL; - vfs_lock_file(filp, F_SETLK, &lock, NULL); + error = vfs_lock_file(filp, F_SETLK, &lock, NULL); if (lock.fl_ops && lock.fl_ops->fl_release_private) lock.fl_ops->fl_release_private(&lock); + trace_locks_remove_posix(file_inode(filp), &lock, error); } EXPORT_SYMBOL(locks_remove_posix); @@ -2715,7 +2748,7 @@ static int __init proc_locks_init(void) proc_create("locks", 0, NULL, &proc_locks_operations); return 0; } -module_init(proc_locks_init); +fs_initcall(proc_locks_init); #endif static int __init filelock_init(void) |