diff options
| author | J. Bruce Fields <bfields@redhat.com> | 2021-08-20 17:02:05 -0400 |
|---|---|---|
| committer | Chuck Lever <chuck.lever@oracle.com> | 2021-08-26 15:32:18 -0400 |
| commit | b840be2f00c0bc00d993f8f76e251052b83e4382 (patch) | |
| tree | 4fc70472ee87ffbed4c62c9a465d0ad2a0b034ef /fs/lockd | |
| parent | f657f8eef3ff870552c9fd2839e0061046f44618 (diff) | |
| download | lwn-b840be2f00c0bc00d993f8f76e251052b83e4382.tar.gz lwn-b840be2f00c0bc00d993f8f76e251052b83e4382.zip | |
lockd: don't attempt blocking locks on nfs reexports
As in the v4 case, it doesn't work well to block waiting for a lock on
an nfs filesystem.
As in the v4 case, that means we're depending on the client to poll.
It's probably incorrect to depend on that, but I *think* clients do poll
in practice. In any case, it's an improvement over hanging the lockd
thread indefinitely as we currently are.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Diffstat (limited to 'fs/lockd')
| -rw-r--r-- | fs/lockd/svclock.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c index a7b4c51667ad..e9b85d8fd5fe 100644 --- a/fs/lockd/svclock.c +++ b/fs/lockd/svclock.c @@ -31,6 +31,7 @@ #include <linux/lockd/nlm.h> #include <linux/lockd/lockd.h> #include <linux/kthread.h> +#include <linux/exportfs.h> #define NLMDBG_FACILITY NLMDBG_SVCLOCK @@ -470,18 +471,24 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file, struct nlm_cookie *cookie, int reclaim) { struct nlm_block *block = NULL; + struct inode *inode = nlmsvc_file_inode(file); int error; int mode; + int async_block = 0; __be32 ret; dprintk("lockd: nlmsvc_lock(%s/%ld, ty=%d, pi=%d, %Ld-%Ld, bl=%d)\n", - nlmsvc_file_inode(file)->i_sb->s_id, - nlmsvc_file_inode(file)->i_ino, + inode->i_sb->s_id, inode->i_ino, lock->fl.fl_type, lock->fl.fl_pid, (long long)lock->fl.fl_start, (long long)lock->fl.fl_end, wait); + if (inode->i_sb->s_export_op->flags & EXPORT_OP_SYNC_LOCKS) { + async_block = wait; + wait = 0; + } + /* Lock file against concurrent access */ mutex_lock(&file->f_mutex); /* Get existing block (in case client is busy-waiting) @@ -542,7 +549,7 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file, */ if (wait) break; - ret = nlm_lck_denied; + ret = async_block ? nlm_lck_blocked : nlm_lck_denied; goto out; case FILE_LOCK_DEFERRED: if (wait) |