From patchwork Tue Jan 16 19:46:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 13521106 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7DFFA7CF3E; Tue, 16 Jan 2024 19:47:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705434458; cv=none; b=S6AaqkBEngVBHE6URGtK+U8Ynf6BtpzBZjoF5L4h6FbUUgA962NgeLPyw2Se5h5x6enYN2cbkaMASs2rO1KwWurNcf3CjturlefH/XMVbgfNHHcaxMISfWVKuV4aUyR7qnO+MYdT4iTI1XO4nFAZ3xIWlYkFs24k2Lv5ugU28pI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705434458; c=relaxed/simple; bh=pwXKsOLMA39qGe1pWMGJ+cEJ/IOGKFqtfcRpJaO4ADs=; h=Received:DKIM-Signature:From:Date:Subject:MIME-Version: Content-Type:Content-Transfer-Encoding:Message-Id:References: In-Reply-To:To:Cc:X-Mailer:X-Developer-Signature:X-Developer-Key; b=uPE6CzsE8GmvGWbJ6zj3KAu2cF+wOR5RJQbpSgVaRkTPwl8QBaHdiywzeWF6dPG3HmaNJbL8zDxx5+cuSeN6pUqzWjYvCkkPTKT4kLnSGVcopNw+sDzqfrOQIywY5l+Ss35dOVxslY2QTPpOWUS7a6Im/dUZQtClkvN/LsQJ9nE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=KX8LQhaG; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="KX8LQhaG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 50558C43390; Tue, 16 Jan 2024 19:47:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705434458; bh=pwXKsOLMA39qGe1pWMGJ+cEJ/IOGKFqtfcRpJaO4ADs=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=KX8LQhaG7gcLIN8wB5hcLNWMPpZkdBfa5pQuw3JMkaLkY3p5HVP3riXhXktFNgcav uNplozIrYQPkL8OE67thPoA4PLrmYTC4yVaSAUXWEi97QkcAOfqhMYNv1TuBphhOHM LrZqUYXOskQkCM9XfNTL7KWPpw9CCIKED12EbN5OnlQrckAMzzq0FPreIr7L1ajCAK ef8edYI5YFSLlXZUXbuZV5iSFnBXGdK4iSr6U+AmYMhCiHahVnYmV5ny1a37BGWloa qHAqQnJKcpA28je/tpx8M+v0bUQzO3wqox6VgfK/XI7H1CTlobiCgRKOvMSQsDRmdo 0eAWhGnNTrMcg== From: Jeff Layton Date: Tue, 16 Jan 2024 14:46:09 -0500 Subject: [PATCH 13/20] filelock: convert __locks_insert_block, conflict and deadlock checks to use file_lock_core Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240116-flsplit-v1-13-c9d0f4370a5d@kernel.org> References: <20240116-flsplit-v1-0-c9d0f4370a5d@kernel.org> In-Reply-To: <20240116-flsplit-v1-0-c9d0f4370a5d@kernel.org> To: Christian Brauner , Alexander Viro , Eric Van Hensbergen , Latchesar Ionkov , Dominique Martinet , Christian Schoenebeck , David Howells , Marc Dionne , Xiubo Li , Ilya Dryomov , Alexander Aring , David Teigland , Miklos Szeredi , Andreas Gruenbacher , Trond Myklebust , Anna Schumaker , Chuck Lever , Neil Brown , Olga Kornievskaia , Dai Ngo , Tom Talpey , Jan Kara , Mark Fasheh , Joel Becker , Joseph Qi , Steve French , Paulo Alcantara , Ronnie Sahlberg , Shyam Prasad N , Namjae Jeon , Sergey Senozhatsky , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers Cc: linux-kernel@vger.kernel.org, v9fs@lists.linux.dev, linux-afs@lists.infradead.org, ceph-devel@vger.kernel.org, gfs2@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, ocfs2-devel@lists.linux.dev, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-trace-kernel@vger.kernel.org, Jeff Layton X-Mailer: b4 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=10881; i=jlayton@kernel.org; h=from:subject:message-id; bh=pwXKsOLMA39qGe1pWMGJ+cEJ/IOGKFqtfcRpJaO4ADs=; b=owEBbQKS/ZANAwAIAQAOaEEZVoIVAcsmYgBlpt0hs8i3UlSny6JLQMGxbpqdfGCP/rIswXMio dcEEduC982JAjMEAAEIAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCZabdIQAKCRAADmhBGVaC FQ9tD/41k11ICXk15Y9Te7Z3HUZHaJn4udDfFN0uHj75kXGXAIHblmPG8U8xiAMtkiIVBJFEXUu jgmjAhkUcoHTIeLH7uijcwJI8VvMSWwf2icK7y1CarU114iJED/NJT9EqPYY29v+flqDTZ6walz W/m15lnn3XhUKVpICHpR5ywmJ0rrBxIG7zbFKTW86qPrQknIuTeQNziZUTTO1j7kKF1SwxzR5N/ gB2/qIHhGvcfNnyl64TfkyJg47o5XdzlpZn1ha35O5T+Ji+UXFG27gTXMhlywhxJ4HPO3Izo8iE 0AzAItP3wRARdJBbc3L+pd8xKZUdCe0XhNDDm9LABfOmPCMa/EyDMwdeFa3bNKeQG2UCMB61SJz /pjR0OrV/Upu39irnotDryYb3MJ9WsuI6j91J5di9veTfin3lqCbRosQ41UE2dB0tO331TGuJIx S8Vi1wwV+OwmcXPfSR4UuVnyTsx6GHeHzQ5+KJQkSueoBsC70bLRhXfNF0p6nHEk+9FwM6iCHKi VYiBz92ICl47NBkgG3xjMyJSVxkvZaoZJD2uOVP+2d+nJzxxhytMoBMXDOHk9wc/5RVw+Dxe3M5 YNklTNCWQ1YFmIm6ylavX+/JfEGIgNWSP1yj9xKbrbxh3zCLN9GkHIAK9RMwNtZyM4k44n8l8U+ L7mvGHfF9WiChBA== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 Have both __locks_insert_block and the deadlock and conflict checking functions take a struct file_lock_core pointer instead of a struct file_lock one. Also, change posix_locks_deadlock to return bool. Signed-off-by: Jeff Layton --- fs/locks.c | 132 ++++++++++++++++++++++++++++++++----------------------------- 1 file changed, 70 insertions(+), 62 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index 6b8e8820dec9..280149860d5e 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -780,42 +780,41 @@ EXPORT_SYMBOL(locks_delete_block); * waiters, and add beneath any waiter that blocks the new waiter. * Thus wakeups don't happen until needed. */ -static void __locks_insert_block(struct file_lock *blocker, - struct file_lock *waiter, - bool conflict(struct file_lock *, - struct file_lock *)) +static void __locks_insert_block(struct file_lock *blocker_fl, + struct file_lock *waiter_fl, + bool conflict(struct file_lock_core *, + struct file_lock_core *)) { - struct file_lock *fl; - struct file_lock_core *bflc; - BUG_ON(!list_empty(&waiter->fl_core.fl_blocked_member)); + struct file_lock_core *blocker = &blocker_fl->fl_core; + struct file_lock_core *waiter = &waiter_fl->fl_core; + struct file_lock_core *flc; + BUG_ON(!list_empty(&waiter->fl_blocked_member)); new_blocker: - list_for_each_entry(fl, &blocker->fl_core.fl_blocked_requests, - fl_core.fl_blocked_member) - if (conflict(fl, waiter)) { - blocker = fl; + list_for_each_entry(flc, &blocker->fl_blocked_requests, fl_blocked_member) + if (conflict(flc, waiter)) { + blocker = flc; goto new_blocker; } - waiter->fl_core.fl_blocker = blocker; - list_add_tail(&waiter->fl_core.fl_blocked_member, - &blocker->fl_core.fl_blocked_requests); + waiter->fl_blocker = file_lock(blocker); + list_add_tail(&waiter->fl_blocked_member, + &blocker->fl_blocked_requests); - bflc = &blocker->fl_core; - if (IS_POSIX(bflc) && !IS_OFDLCK(bflc)) - locks_insert_global_blocked(&waiter->fl_core); + 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->fl_core); + __locks_wake_up_blocks(waiter); } /* Must be called with flc_lock held. */ static void locks_insert_block(struct file_lock *blocker, struct file_lock *waiter, - bool conflict(struct file_lock *, - struct file_lock *)) + bool conflict(struct file_lock_core *, + struct file_lock_core *)) { spin_lock(&blocked_lock_lock); __locks_insert_block(blocker, waiter, conflict); @@ -872,12 +871,12 @@ locks_delete_lock_ctx(struct file_lock *fl, struct list_head *dispose) /* Determine if lock sys_fl blocks lock caller_fl. Common functionality * checks for shared/exclusive status of overlapping locks. */ -static bool locks_conflict(struct file_lock *caller_fl, - struct file_lock *sys_fl) +static bool locks_conflict(struct file_lock_core *caller_fl, + struct file_lock_core *sys_fl) { - if (sys_fl->fl_core.fl_type == F_WRLCK) + if (sys_fl->fl_type == F_WRLCK) return true; - if (caller_fl->fl_core.fl_type == F_WRLCK) + if (caller_fl->fl_type == F_WRLCK) return true; return false; } @@ -885,20 +884,23 @@ static bool locks_conflict(struct file_lock *caller_fl, /* Determine if lock sys_fl blocks lock caller_fl. POSIX specific * checking before calling the locks_conflict(). */ -static bool posix_locks_conflict(struct file_lock *caller_fl, - struct file_lock *sys_fl) +static bool posix_locks_conflict(struct file_lock_core *caller_flc, + struct file_lock_core *sys_flc) { + struct file_lock *caller_fl = file_lock(caller_flc); + struct file_lock *sys_fl = file_lock(sys_flc); + /* POSIX locks owned by the same process do not conflict with * each other. */ - if (posix_same_owner(&caller_fl->fl_core, &sys_fl->fl_core)) + if (posix_same_owner(caller_flc, sys_flc)) return false; /* Check whether they overlap */ if (!locks_overlap(caller_fl, sys_fl)) return false; - return locks_conflict(caller_fl, sys_fl); + return locks_conflict(caller_flc, sys_flc); } /* Determine if lock sys_fl blocks lock caller_fl. Used on xx_GETLK @@ -907,28 +909,31 @@ static bool posix_locks_conflict(struct file_lock *caller_fl, static bool posix_test_locks_conflict(struct file_lock *caller_fl, struct file_lock *sys_fl) { + struct file_lock_core *caller = &caller_fl->fl_core; + struct file_lock_core *sys = &sys_fl->fl_core; + /* F_UNLCK checks any locks on the same fd. */ - if (caller_fl->fl_core.fl_type == F_UNLCK) { - if (!posix_same_owner(&caller_fl->fl_core, &sys_fl->fl_core)) + if (caller->fl_type == F_UNLCK) { + if (!posix_same_owner(caller, sys)) return false; return locks_overlap(caller_fl, sys_fl); } - return posix_locks_conflict(caller_fl, sys_fl); + return posix_locks_conflict(caller, sys); } /* Determine if lock sys_fl blocks lock caller_fl. FLOCK specific * checking before calling the locks_conflict(). */ -static bool flock_locks_conflict(struct file_lock *caller_fl, - struct file_lock *sys_fl) +static bool flock_locks_conflict(struct file_lock_core *caller_flc, + struct file_lock_core *sys_flc) { /* FLOCK locks referring to the same filp do not conflict with * each other. */ - if (caller_fl->fl_core.fl_file == sys_fl->fl_core.fl_file) + if (caller_flc->fl_file == sys_flc->fl_file) return false; - return locks_conflict(caller_fl, sys_fl); + return locks_conflict(caller_flc, sys_flc); } void @@ -1006,27 +1011,28 @@ EXPORT_SYMBOL(posix_test_lock); #define MAX_DEADLK_ITERATIONS 10 -/* 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) +/* Find a lock that the owner of the given @blocker is blocking on. */ +static struct file_lock_core *what_owner_is_waiting_for(struct file_lock_core *blocker) { - struct file_lock *fl; + struct file_lock_core *flc; - hash_for_each_possible(blocked_hash, fl, fl_core.fl_link, posix_owner_key(&block_fl->fl_core)) { - if (posix_same_owner(&fl->fl_core, &block_fl->fl_core)) { - while (fl->fl_core.fl_blocker) - fl = fl->fl_core.fl_blocker; - return fl; + hash_for_each_possible(blocked_hash, flc, fl_link, posix_owner_key(blocker)) { + if (posix_same_owner(flc, blocker)) { + while (flc->fl_blocker) + flc = &flc->fl_blocker->fl_core; + return flc; } } return NULL; } /* Must be called with the blocked_lock_lock held! */ -static int posix_locks_deadlock(struct file_lock *caller_fl, - struct file_lock *block_fl) +static bool posix_locks_deadlock(struct file_lock *caller_fl, + struct file_lock *block_fl) { + struct file_lock_core *caller = &caller_fl->fl_core; + struct file_lock_core *blocker = &block_fl->fl_core; int i = 0; - struct file_lock_core *flc = &caller_fl->fl_core; lockdep_assert_held(&blocked_lock_lock); @@ -1034,16 +1040,16 @@ static int posix_locks_deadlock(struct file_lock *caller_fl, * This deadlock detector can't reasonably detect deadlocks with * FL_OFDLCK locks, since they aren't owned by a process, per-se. */ - if (IS_OFDLCK(flc)) + if (IS_OFDLCK(caller)) return 0; - while ((block_fl = what_owner_is_waiting_for(block_fl))) { + while ((blocker = what_owner_is_waiting_for(blocker))) { if (i++ > MAX_DEADLK_ITERATIONS) - return 0; - if (posix_same_owner(&caller_fl->fl_core, &block_fl->fl_core)) - return 1; + return false; + if (posix_same_owner(caller, blocker)) + return true; } - return 0; + return false; } /* Try to create a FLOCK lock on filp. We always insert new FLOCK locks @@ -1098,7 +1104,7 @@ static int flock_lock_inode(struct inode *inode, struct file_lock *request) find_conflict: list_for_each_entry(fl, &ctx->flc_flock, fl_core.fl_list) { - if (!flock_locks_conflict(request, fl)) + if (!flock_locks_conflict(&request->fl_core, &fl->fl_core)) continue; error = -EAGAIN; if (!(request->fl_core.fl_flags & FL_SLEEP)) @@ -1167,7 +1173,7 @@ static int posix_lock_inode(struct inode *inode, struct file_lock *request, */ if (request->fl_core.fl_type != F_UNLCK) { list_for_each_entry(fl, &ctx->flc_posix, fl_core.fl_list) { - if (!posix_locks_conflict(request, fl)) + if (!posix_locks_conflict(&request->fl_core, &fl->fl_core)) continue; if (fl->fl_lmops && fl->fl_lmops->lm_lock_expirable && (*fl->fl_lmops->lm_lock_expirable)(fl)) { @@ -1469,23 +1475,25 @@ static void time_out_leases(struct inode *inode, struct list_head *dispose) } } -static bool leases_conflict(struct file_lock *lease, struct file_lock *breaker) +static bool leases_conflict(struct file_lock_core *lc, struct file_lock_core *bc) { bool rc; + struct file_lock *lease = file_lock(lc); + struct file_lock *breaker = file_lock(bc); if (lease->fl_lmops->lm_breaker_owns_lease && lease->fl_lmops->lm_breaker_owns_lease(lease)) return false; - if ((breaker->fl_core.fl_flags & FL_LAYOUT) != (lease->fl_core.fl_flags & FL_LAYOUT)) { + if ((bc->fl_flags & FL_LAYOUT) != (lc->fl_flags & FL_LAYOUT)) { rc = false; goto trace; } - if ((breaker->fl_core.fl_flags & FL_DELEG) && (lease->fl_core.fl_flags & FL_LEASE)) { + if ((bc->fl_flags & FL_DELEG) && (lc->fl_flags & FL_LEASE)) { rc = false; goto trace; } - rc = locks_conflict(breaker, lease); + rc = locks_conflict(bc, lc); trace: trace_leases_conflict(rc, lease, breaker); return rc; @@ -1495,12 +1503,12 @@ static bool any_leases_conflict(struct inode *inode, struct file_lock *breaker) { struct file_lock_context *ctx = inode->i_flctx; - struct file_lock *fl; + struct file_lock_core *flc; lockdep_assert_held(&ctx->flc_lock); - list_for_each_entry(fl, &ctx->flc_lease, fl_core.fl_list) { - if (leases_conflict(fl, breaker)) + list_for_each_entry(flc, &ctx->flc_lease, fl_list) { + if (leases_conflict(flc, &breaker->fl_core)) return true; } return false; @@ -1556,7 +1564,7 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type) } list_for_each_entry_safe(fl, tmp, &ctx->flc_lease, fl_core.fl_list) { - if (!leases_conflict(fl, new_fl)) + if (!leases_conflict(&fl->fl_core, &new_fl->fl_core)) continue; if (want_write) { if (fl->fl_core.fl_flags & FL_UNLOCK_PENDING)