X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Flocks.c;h=11dbf08651b70861d31530ef73436dc2e3beffc1;hb=bb6dfb32f90094fea647e1f27d994a8b6ddd2766;hp=c3eecb895acf1346944d2dd3af217cf11c9c0f5a;hpb=b533184fc353d4a2d07929b4ac424a6f1bf5a3b9;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/locks.c b/fs/locks.c index c3eecb8..11dbf08 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -116,6 +116,7 @@ #include #include +#include #include #include #include @@ -125,8 +126,8 @@ #include #include #include +#include -#include #include #define IS_POSIX(fl) (fl->fl_flags & FL_POSIX) @@ -185,6 +186,7 @@ void locks_init_lock(struct file_lock *fl) fl->fl_fasync = NULL; fl->fl_owner = NULL; fl->fl_pid = 0; + fl->fl_nspid = NULL; fl->fl_file = NULL; fl->fl_flags = 0; fl->fl_type = 0; @@ -223,7 +225,7 @@ static void locks_copy_private(struct file_lock *new, struct file_lock *fl) /* * Initialize a new lock from an existing file_lock structure. */ -static void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl) +void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl) { new->fl_owner = fl->fl_owner; new->fl_pid = fl->fl_pid; @@ -235,6 +237,7 @@ static void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl) new->fl_ops = NULL; new->fl_lmops = NULL; } +EXPORT_SYMBOL(__locks_copy_lock); void locks_copy_lock(struct file_lock *new, struct file_lock *fl) { @@ -553,6 +556,8 @@ static void locks_insert_lock(struct file_lock **pos, struct file_lock *fl) { list_add(&fl->fl_link, &file_lock_list); + fl->fl_nspid = get_pid(task_tgid(current)); + /* insert into file's list */ fl->fl_next = *pos; *pos = fl; @@ -584,6 +589,11 @@ static void locks_delete_lock(struct file_lock **thisfl_p) if (fl->fl_ops && fl->fl_ops->fl_remove) fl->fl_ops->fl_remove(fl); + if (fl->fl_nspid) { + put_pid(fl->fl_nspid); + fl->fl_nspid = NULL; + } + locks_wake_up_blocks(fl); locks_free_lock(fl); } @@ -634,33 +644,6 @@ static int flock_locks_conflict(struct file_lock *caller_fl, struct file_lock *s return (locks_conflict(caller_fl, sys_fl)); } -static int interruptible_sleep_on_locked(wait_queue_head_t *fl_wait, int timeout) -{ - int result = 0; - DECLARE_WAITQUEUE(wait, current); - - __set_current_state(TASK_INTERRUPTIBLE); - add_wait_queue(fl_wait, &wait); - if (timeout == 0) - schedule(); - else - result = schedule_timeout(timeout); - if (signal_pending(current)) - result = -ERESTARTSYS; - remove_wait_queue(fl_wait, &wait); - __set_current_state(TASK_RUNNING); - return result; -} - -static int locks_block_on_timeout(struct file_lock *blocker, struct file_lock *waiter, int time) -{ - int result; - locks_insert_block(blocker, waiter); - result = interruptible_sleep_on_locked(&waiter->fl_wait, time); - __locks_delete_block(waiter); - return result; -} - void posix_test_lock(struct file *filp, struct file_lock *fl) { @@ -673,14 +656,15 @@ posix_test_lock(struct file *filp, struct file_lock *fl) if (posix_locks_conflict(fl, cfl)) break; } - if (cfl) + if (cfl) { __locks_copy_lock(fl, cfl); - else + if (cfl->fl_nspid) + fl->fl_pid = pid_vnr(cfl->fl_nspid); + } else fl->fl_type = F_UNLCK; unlock_kernel(); return; } - EXPORT_SYMBOL(posix_test_lock); /* @@ -789,7 +773,7 @@ static int flock_lock_file(struct file *filp, struct file_lock *request) * give it the opportunity to lock the file. */ if (found) - cond_resched(); + cond_resched_bkl(); find_conflict: for_each_lock(inode, before) { @@ -851,7 +835,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str if (!posix_locks_conflict(request, fl)) continue; if (conflock) - locks_copy_lock(conflock, fl); + __locks_copy_lock(conflock, fl); error = -EAGAIN; if (!(request->fl_flags & FL_SLEEP)) goto out; @@ -1266,7 +1250,10 @@ restart: if (break_time == 0) break_time++; } - error = locks_block_on_timeout(flock, new_fl, break_time); + locks_insert_block(flock, new_fl); + error = wait_event_interruptible_timeout(new_fl->fl_wait, + !new_fl->fl_next, break_time); + __locks_delete_block(new_fl); if (error >= 0) { if (error == 0) time_out_leases(inode); @@ -1289,13 +1276,13 @@ out: EXPORT_SYMBOL(__break_lease); /** - * lease_get_mtime + * lease_get_mtime - get the last modified time of an inode * @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 - * exclusive lease, then they could be modifiying it. + * exclusive lease, then they could be modifying it. */ void lease_get_mtime(struct inode *inode, struct timespec *time) { @@ -1382,18 +1369,20 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp) lease = *flp; - error = -EAGAIN; - if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0)) - goto out; - if ((arg == F_WRLCK) - && ((atomic_read(&dentry->d_count) > 1) - || (atomic_read(&inode->i_count) > 1))) - goto out; + if (arg != F_UNLCK) { + error = -ENOMEM; + new_fl = locks_alloc_lock(); + if (new_fl == NULL) + goto out; - error = -ENOMEM; - new_fl = locks_alloc_lock(); - if (new_fl == NULL) - goto out; + error = -EAGAIN; + if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0)) + goto out; + if ((arg == F_WRLCK) + && ((atomic_read(&dentry->d_count) > 1) + || (atomic_read(&inode->i_count) > 1))) + goto out; + } /* * At this point, we know that if there is an exclusive @@ -1419,6 +1408,7 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp) rdlease_count++; } + error = -EAGAIN; if ((arg == F_RDLCK && (wrlease_count > 0)) || (arg == F_WRLCK && ((rdlease_count + wrlease_count) > 0))) goto out; @@ -1505,8 +1495,7 @@ EXPORT_SYMBOL_GPL(vfs_setlease); int fcntl_setlease(unsigned int fd, struct file *filp, long arg) { struct file_lock fl, *flp = &fl; - struct dentry *dentry = filp->f_path.dentry; - struct inode *inode = dentry->d_inode; + struct inode *inode = filp->f_path.dentry->d_inode; int error; locks_init_lock(&fl); @@ -1764,6 +1753,7 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, struct file_lock *file_lock = locks_alloc_lock(); struct flock flock; struct inode *inode; + struct file *f; int error; if (file_lock == NULL) @@ -1815,24 +1805,36 @@ again: if (error) goto out; - for (;;) { - error = vfs_lock_file(filp, cmd, file_lock, NULL); - if (error != -EAGAIN || cmd == F_SETLK) - break; - error = wait_event_interruptible(file_lock->fl_wait, - !file_lock->fl_next); - if (!error) - continue; + if (filp->f_op && filp->f_op->lock != NULL) + error = filp->f_op->lock(filp, cmd, file_lock); + else { + for (;;) { + error = posix_lock_file(filp, file_lock, NULL); + if (error != -EAGAIN || cmd == F_SETLK) + break; + error = wait_event_interruptible(file_lock->fl_wait, + !file_lock->fl_next); + if (!error) + continue; - locks_delete_block(file_lock); - break; + locks_delete_block(file_lock); + break; + } } /* * Attempt to detect a close/fcntl race and recover by * releasing the lock that was just acquired. */ - if (!error && fcheck(fd) != filp && flock.l_type != F_UNLCK) { + /* + * 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) { flock.l_type = F_UNLCK; goto again; } @@ -1888,6 +1890,7 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd, struct file_lock *file_lock = locks_alloc_lock(); struct flock64 flock; struct inode *inode; + struct file *f; int error; if (file_lock == NULL) @@ -1939,24 +1942,31 @@ again: if (error) goto out; - for (;;) { - error = vfs_lock_file(filp, cmd, file_lock, NULL); - if (error != -EAGAIN || cmd == F_SETLK64) - break; - error = wait_event_interruptible(file_lock->fl_wait, - !file_lock->fl_next); - if (!error) - continue; + if (filp->f_op && filp->f_op->lock != NULL) + error = filp->f_op->lock(filp, cmd, file_lock); + else { + for (;;) { + error = posix_lock_file(filp, file_lock, NULL); + if (error != -EAGAIN || cmd == F_SETLK64) + break; + error = wait_event_interruptible(file_lock->fl_wait, + !file_lock->fl_next); + if (!error) + continue; - locks_delete_block(file_lock); - break; + locks_delete_block(file_lock); + break; + } } /* * Attempt to detect a close/fcntl race and recover by * releasing the lock that was just acquired. */ - if (!error && fcheck(fd) != filp && flock.l_type != F_UNLCK) { + spin_lock(¤t->files->file_lock); + f = fcheck(fd); + spin_unlock(¤t->files->file_lock); + if (!error && f != filp && flock.l_type != F_UNLCK) { flock.l_type = F_UNLCK; goto again; } @@ -2094,6 +2104,12 @@ static void lock_get_status(struct seq_file *f, struct file_lock *fl, int id, char *pfx) { struct inode *inode = NULL; + unsigned int fl_pid; + + if (fl->fl_nspid) + fl_pid = pid_vnr(fl->fl_nspid); + else + fl_pid = fl->fl_pid; if (fl->fl_file != NULL) inode = fl->fl_file->f_path.dentry->d_inode; @@ -2134,16 +2150,16 @@ static void lock_get_status(struct seq_file *f, struct file_lock *fl, } if (inode) { #ifdef WE_CAN_BREAK_LSLK_NOW - seq_printf(f, "%d %s:%ld ", fl->fl_pid, + seq_printf(f, "%d %s:%ld ", fl_pid, inode->i_sb->s_id, inode->i_ino); #else /* userspace relies on this representation of dev_t ;-( */ - seq_printf(f, "%d %02x:%02x:%ld ", fl->fl_pid, + seq_printf(f, "%d %02x:%02x:%ld ", fl_pid, MAJOR(inode->i_sb->s_dev), MINOR(inode->i_sb->s_dev), inode->i_ino); #endif } else { - seq_printf(f, "%d :0 ", fl->fl_pid); + seq_printf(f, "%d :0 ", fl_pid); } if (IS_POSIX(fl)) { if (fl->fl_end == OFFSET_MAX)