diff options
Diffstat (limited to '')
| -rw-r--r-- | fs/locks.c | 43 |
1 files changed, 37 insertions, 6 deletions
diff --git a/fs/locks.c b/fs/locks.c index 492d970c67d7..1260c265ba62 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -402,6 +402,24 @@ void locks_copy_lock(struct file_lock *new, struct file_lock *fl) EXPORT_SYMBOL(locks_copy_lock); +static void locks_move_blocks(struct file_lock *new, struct file_lock *fl) +{ + struct file_lock *f; + + /* + * As ctx->flc_lock is held, new requests cannot be added to + * ->fl_blocked_requests, so we don't need a lock to check if it + * is empty. + */ + if (list_empty(&fl->fl_blocked_requests)) + return; + spin_lock(&blocked_lock_lock); + list_splice_init(&fl->fl_blocked_requests, &new->fl_blocked_requests); + list_for_each_entry(f, &fl->fl_blocked_requests, fl_blocked_member) + f->fl_blocker = new; + spin_unlock(&blocked_lock_lock); +} + static inline int flock_translate_cmd(int cmd) { if (cmd & LOCK_MAND) return cmd & (LOCK_MAND | LOCK_RW); @@ -693,6 +711,7 @@ static void __locks_wake_up_blocks(struct file_lock *blocker) static void locks_delete_block(struct file_lock *waiter) { spin_lock(&blocked_lock_lock); + __locks_wake_up_blocks(waiter); __locks_delete_block(waiter); spin_unlock(&blocked_lock_lock); } @@ -716,6 +735,12 @@ static void __locks_insert_block(struct file_lock *blocker, list_add_tail(&waiter->fl_blocked_member, &blocker->fl_blocked_requests); if (IS_POSIX(blocker) && !IS_OFDLCK(blocker)) locks_insert_global_blocked(waiter); + + /* The requests in waiter->fl_blocked are known to conflict with + * waiter, but might not conflict with blocker, or the requests + * and lock which block it. So they all need to be woken. + */ + __locks_wake_up_blocks(waiter); } /* Must be called with flc_lock held. */ @@ -888,8 +913,11 @@ static struct file_lock *what_owner_is_waiting_for(struct file_lock *block_fl) struct file_lock *fl; hash_for_each_possible(blocked_hash, fl, fl_link, posix_owner_key(block_fl)) { - if (posix_same_owner(fl, block_fl)) - return fl->fl_blocker; + if (posix_same_owner(fl, block_fl)) { + while (fl->fl_blocker) + fl = fl->fl_blocker; + return fl; + } } return NULL; } @@ -982,6 +1010,7 @@ find_conflict: if (request->fl_flags & FL_ACCESS) goto out; locks_copy_lock(new_fl, request); + locks_move_blocks(new_fl, request); locks_insert_lock_ctx(new_fl, &ctx->flc_flock); new_fl = NULL; error = 0; @@ -1175,6 +1204,7 @@ static int posix_lock_inode(struct inode *inode, struct file_lock *request, goto out; } locks_copy_lock(new_fl, request); + locks_move_blocks(new_fl, request); locks_insert_lock_ctx(new_fl, &fl->fl_list); fl = new_fl; new_fl = NULL; @@ -2586,13 +2616,14 @@ void locks_remove_file(struct file *filp) int posix_unblock_lock(struct file_lock *waiter) { - int status = 0; + int status = -ENOENT; spin_lock(&blocked_lock_lock); - if (waiter->fl_blocker) + if (waiter->fl_blocker) { + __locks_wake_up_blocks(waiter); __locks_delete_block(waiter); - else - status = -ENOENT; + status = 0; + } spin_unlock(&blocked_lock_lock); return status; } |