NLM/NFSD: Fix lock notifications for async-capable filesystems

Instead of checking just the exportfs flag, use the new
locks_can_async_lock() helper which allows NLM and NFSD to once again
support lock notifications for all filesystems which use posix_lock_file().

Signed-off-by: Benjamin Coddington <[email protected]>
Link: https://lore.kernel.org/r/865c40da44af67939e8eb560d17a26c9c50f23e0.1726083391.git.bcodding@redhat.com
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index 1f2149db10f2469562fce16af291246dbeae9ee6..2359347c9fbd0fc1064f63c99af539aa5f15d657 100644 (file)
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -30,7 +30,6 @@
 #include <linux/sunrpc/svc_xprt.h>
 #include <linux/lockd/nlm.h>
 #include <linux/lockd/lockd.h>
-#include <linux/exportfs.h>
 
 #define NLMDBG_FACILITY                NLMDBG_SVCLOCK
 
@@ -481,7 +480,7 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
            struct nlm_host *host, struct nlm_lock *lock, int wait,
            struct nlm_cookie *cookie, int reclaim)
 {
-       struct inode            *inode = nlmsvc_file_inode(file);
+       struct inode            *inode __maybe_unused = nlmsvc_file_inode(file);
        struct nlm_block        *block = NULL;
        int                     error;
        int                     mode;
@@ -496,7 +495,7 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
                                (long long)lock->fl.fl_end,
                                wait);
 
-       if (!exportfs_lock_op_is_async(inode->i_sb->s_export_op)) {
+       if (!locks_can_async_lock(nlmsvc_file_file(file)->f_op)) {
                async_block = wait;
                wait = 0;
        }
@@ -550,7 +549,7 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
         * requests on the underlaying ->lock() implementation but
         * only one nlm_block to being granted by lm_grant().
         */
-       if (exportfs_lock_op_is_async(inode->i_sb->s_export_op) &&
+       if (locks_can_async_lock(nlmsvc_file_file(file)->f_op) &&
            !list_empty(&block->b_list)) {
                spin_unlock(&nlm_blocked_lock);
                ret = nlm_lck_blocked;

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index a366fb1c1b9b4f23a290ed96449ce0614a149207..a061987abee37525ec893f8cd3c35eaa77996382 100644 (file)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -7953,9 +7953,6 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
        fp = lock_stp->st_stid.sc_file;
        switch (lock->lk_type) {
                case NFS4_READW_LT:
-                       if (nfsd4_has_session(cstate) ||
-                           exportfs_lock_op_is_async(sb->s_export_op))
-                               flags |= FL_SLEEP;
                        fallthrough;
                case NFS4_READ_LT:
                        spin_lock(&fp->fi_lock);
@@ -7966,9 +7963,6 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                        type = F_RDLCK;
                        break;
                case NFS4_WRITEW_LT:
-                       if (nfsd4_has_session(cstate) ||
-                           exportfs_lock_op_is_async(sb->s_export_op))
-                               flags |= FL_SLEEP;
                        fallthrough;
                case NFS4_WRITE_LT:
                        spin_lock(&fp->fi_lock);
@@ -7988,15 +7982,10 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                goto out;
        }
 
-       /*
-        * Most filesystems with their own ->lock operations will block
-        * the nfsd thread waiting to acquire the lock.  That leads to
-        * deadlocks (we don't want every nfsd thread tied up waiting
-        * for file locks), so don't attempt blocking lock notifications
-        * on those filesystems:
-        */
-       if (!exportfs_lock_op_is_async(sb->s_export_op))
-               flags &= ~FL_SLEEP;
+       if (lock->lk_type & (NFS4_READW_LT | NFS4_WRITEW_LT) &&
+               nfsd4_has_session(cstate) &&
+               locks_can_async_lock(nf->nf_file->f_op))
+                       flags |= FL_SLEEP;
 
        nbl = find_or_allocate_block(lock_sop, &fp->fi_fhandle, nn);
        if (!nbl) {