From patchwork Thu Jan 25 10:43:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 13530402 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 2986A60B9B; Thu, 25 Jan 2024 10:44:31 +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=1706179472; cv=none; b=mGrNuil0NGIUDKBrcx2wKkiIZ4FJMrByI1vh9TYqLD7am3Tcc28WVWv28cVp1lawiuOHDYjvSlTIA6yPIqZNfBe+E2BXZ9Ck84SL2d6EPb4xJY9ZfpOeHMJ3HCQZ1curQ8MgkOBFwuODz2Wl3EI8H/uwXG9KuYc3XtfjpNClQcQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706179472; c=relaxed/simple; bh=Ghbte5EbxS7nyasl+Gb2DnaWu0CsjIyjXTgQhNH8UK4=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=VA11Z0dxCJae+F1dTIrCfH6rRg2wQf3XTc/hFLzV/bE8ejf7822jTMR9blTHTJhEwrGzllsJOnR3WDVeU4uw+sR5Wu4sTUzrlyzvZRVrjR7CrTMGBO7tlgyFNeMhiYbrrn0oP1H1/Ncs4kxeYrDoakm9USUtPrzLpS9bXn1mtgE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HYNbZ34m; 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="HYNbZ34m" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1EDC1C43399; Thu, 25 Jan 2024 10:44:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706179471; bh=Ghbte5EbxS7nyasl+Gb2DnaWu0CsjIyjXTgQhNH8UK4=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=HYNbZ34m8uZQXpO00B79Hjf6dBM4nPvPZSVbPtgJBkhrIVKvI2WHn3rw6MLclixfE 8o8gXeOFmC2eITDSSdEeqXsKU6Qrezk8LB6L0s5w1TGSNF6+jcPyW5+rYsWyal4LtH oyxODhKIt00Hli33Y4l893GYNXXEjidBw7S8C8rjZFpZPEL/HcIq0k2IOdgK9PO7LZ hFrjK1rz5OetZpbGI5rkxFBx8dJOVU65sd7GU4tjUWIfMow6NXL7j2A1p3l0JamT4x Cm9tlVtvHHisgLMvS/071UOpoI1gwHb98gvAAlL1bvGx3h/K61ZC7jWbTBrhXZKFF9 7Y7I1oAaSMaKg== From: Jeff Layton Date: Thu, 25 Jan 2024 05:43:01 -0500 Subject: [PATCH v2 20/41] 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: <20240125-flsplit-v2-20-7485322b62c7@kernel.org> References: <20240125-flsplit-v2-0-7485322b62c7@kernel.org> In-Reply-To: <20240125-flsplit-v2-0-7485322b62c7@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 , Shyam Prasad N , Namjae Jeon , Sergey Senozhatsky , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Ronnie Sahlberg 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, linux-trace-kernel@vger.kernel.org, Jeff Layton X-Mailer: b4 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=10987; i=jlayton@kernel.org; h=from:subject:message-id; bh=Ghbte5EbxS7nyasl+Gb2DnaWu0CsjIyjXTgQhNH8UK4=; b=owEBbQKS/ZANAwAIAQAOaEEZVoIVAcsmYgBlsjs8H6APyCBiq/PBoIYn3BDdbi8o+VVElAlQX 8ov6ZUnCfSJAjMEAAEIAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCZbI7PAAKCRAADmhBGVaC FRTUEACgqkoVOH/M6C8gDaH3qq1l2QqyHcik8rnZgTJ1H5xgXr80OkqyZMpavgfPsoP2S+ygf9h VAyd+sPCux6LKaWpIA47Ae3N643sqzAV/C2BCGa58fJBU5KTfo15zdX4+uGqPlireIVmxYUJ1PR FOm0UEjp4zaxVFCwfWGXPnPRAC4TvfWYEkAuQiekNKFNIyq89P9agy/nDjCu3yCWvON2GNQ1422 erInykImjOmsS9T+jdSyr0A+vVYVZKI+7AlkmGS154ODu2xGiv+q81O2qWj4sA0MaXX07tgz1bg xGGemeBqJIQWqD0xBPlAalitL7Fe8fgLZKDOiCyig1jKR0wHL6V4dxpHMhgzA6ZkPAPNEbtrigS Fj5aUlTcEWDRVVjgk4Ea5e7bndAcsZk4IcsOzVy04iz2l6Lxp6cEznGyRqy3++nXN7/pkJXp5ok fIJbqZjRRdJwvvPjO7NyMaFwQto8Q5T2Rx0n8DHaOdHPEbhuXf+N9Ok27N8TdHyYbGcO2mVHXgS Gl61qKtgoSsRWvMFSiCRuo/n5CvB+LFVjC16qdV/lyFIzNk0jzXOvp+FGeObc4XQiUwaB8aG6je qAQLJThOxZqZTmD8wfRQ+orN6Q/fN0fevaHv5p4pAsRDBcmkvvH8w+jNF/504LFt1PGK3pVq+JT hhRwYzO65pbsyYg== 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 | 134 +++++++++++++++++++++++++++++++++---------------------------- 1 file changed, 73 insertions(+), 61 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index fb113103dc1b..a86841fc8220 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -757,39 +757,41 @@ 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; - BUG_ON(!list_empty(&waiter->fl_core.flc_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->flc_blocked_member)); new_blocker: - list_for_each_entry(fl, &blocker->fl_core.flc_blocked_requests, - fl_core.flc_blocked_member) - if (conflict(fl, waiter)) { - blocker = fl; + list_for_each_entry(flc, &blocker->flc_blocked_requests, flc_blocked_member) + if (conflict(flc, waiter)) { + blocker = flc; goto new_blocker; } - waiter->fl_core.flc_blocker = blocker; - list_add_tail(&waiter->fl_core.flc_blocked_member, - &blocker->fl_core.flc_blocked_requests); - if ((blocker->fl_core.flc_flags & (FL_POSIX|FL_OFDLCK)) == FL_POSIX) - locks_insert_global_blocked(&waiter->fl_core); + waiter->flc_blocker = file_lock(blocker); + list_add_tail(&waiter->flc_blocked_member, + &blocker->flc_blocked_requests); - /* The requests in waiter->fl_blocked are known to conflict with + if ((blocker->flc_flags & (FL_POSIX|FL_OFDLCK)) == (FL_POSIX|FL_OFDLCK)) + locks_insert_global_blocked(waiter); + + /* The requests in waiter->flc_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); @@ -846,12 +848,12 @@ 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.flc_type == F_WRLCK) + if (sys_fl->flc_type == F_WRLCK) return true; - if (caller_fl->fl_core.flc_type == F_WRLCK) + if (caller_fl->flc_type == F_WRLCK) return true; return false; } @@ -859,20 +861,23 @@ 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 @@ -881,28 +886,31 @@ 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.flc_type == F_UNLCK) { - if (!posix_same_owner(&caller_fl->fl_core, &sys_fl->fl_core)) + if (caller->flc_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.flc_file == sys_fl->fl_core.flc_file) + if (caller_flc->flc_file == sys_flc->flc_file) return false; - return locks_conflict(caller_fl, sys_fl); + return locks_conflict(caller_flc, sys_flc); } void @@ -980,25 +988,27 @@ 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.flc_link, posix_owner_key(&block_fl->fl_core)) { - if (posix_same_owner(&fl->fl_core, &block_fl->fl_core)) { - while (fl->fl_core.flc_blocker) - fl = fl->fl_core.flc_blocker; - return fl; + hash_for_each_possible(blocked_hash, flc, flc_link, posix_owner_key(blocker)) { + if (posix_same_owner(flc, blocker)) { + while (flc->flc_blocker) + flc = &flc->flc_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; lockdep_assert_held(&blocked_lock_lock); @@ -1007,16 +1017,16 @@ 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 (caller_fl->fl_core.flc_flags & FL_OFDLCK) - return 0; + if (caller->flc_flags & FL_OFDLCK) + return false; - 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 @@ -1071,7 +1081,7 @@ static int flock_lock_inode(struct inode *inode, struct file_lock *request) find_conflict: list_for_each_entry(fl, &ctx->flc_flock, fl_core.flc_list) { - if (!flock_locks_conflict(request, fl)) + if (!flock_locks_conflict(&request->fl_core, &fl->fl_core)) continue; error = -EAGAIN; if (!(request->fl_core.flc_flags & FL_SLEEP)) @@ -1140,7 +1150,7 @@ static int posix_lock_inode(struct inode *inode, struct file_lock *request, */ if (request->fl_core.flc_type != F_UNLCK) { list_for_each_entry(fl, &ctx->flc_posix, fl_core.flc_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)) { @@ -1442,23 +1452,25 @@ 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.flc_flags & FL_LAYOUT) != (lease->fl_core.flc_flags & FL_LAYOUT)) { + if ((bc->flc_flags & FL_LAYOUT) != (lc->flc_flags & FL_LAYOUT)) { rc = false; goto trace; } - if ((breaker->fl_core.flc_flags & FL_DELEG) && (lease->fl_core.flc_flags & FL_LEASE)) { + if ((bc->flc_flags & FL_DELEG) && (lc->flc_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; @@ -1468,12 +1480,12 @@ 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.flc_list) { - if (leases_conflict(fl, breaker)) + list_for_each_entry(flc, &ctx->flc_lease, flc_list) { + if (leases_conflict(flc, &breaker->fl_core)) return true; } return false; @@ -1529,7 +1541,7 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type) } list_for_each_entry_safe(fl, tmp, &ctx->flc_lease, fl_core.flc_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.flc_flags & FL_UNLOCK_PENDING)