[ Upstream commit 5e172f75e51e3de1b4274146d9b990f803cb5c2a ]
The default P9_LOCK_TIMEOUT can be too long for some users exporting a local file system to a guest VM (30s), make this configurable at mount time.
Link: http://lkml.kernel.org/r/1536295827-3181-1-git-send-email-asmadeus@codewreck... Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195727 Signed-off-by: Dinu-Razvan Chis-Serban justcsdr@gmail.com Signed-off-by: Dominique Martinet dominique.martinet@cea.fr Signed-off-by: Sasha Levin sashal@kernel.org --- fs/9p/v9fs.c | 21 +++++++++++++++++++++ fs/9p/v9fs.h | 1 + fs/9p/vfs_file.c | 6 +++++- 3 files changed, 27 insertions(+), 1 deletion(-)
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c index 6caca025019d..1e9bb8db7b48 100644 --- a/fs/9p/v9fs.c +++ b/fs/9p/v9fs.c @@ -59,6 +59,8 @@ enum { Opt_cache_loose, Opt_fscache, Opt_mmap, /* Access options */ Opt_access, Opt_posixacl, + /* Lock timeout option */ + Opt_locktimeout, /* Error token */ Opt_err }; @@ -78,6 +80,7 @@ static const match_table_t tokens = { {Opt_cachetag, "cachetag=%s"}, {Opt_access, "access=%s"}, {Opt_posixacl, "posixacl"}, + {Opt_locktimeout, "locktimeout=%u"}, {Opt_err, NULL} };
@@ -126,6 +129,7 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts) #ifdef CONFIG_9P_FSCACHE v9ses->cachetag = NULL; #endif + v9ses->session_lock_timeout = P9_LOCK_TIMEOUT;
if (!opts) return 0; @@ -298,6 +302,23 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts) #endif break;
+ case Opt_locktimeout: + r = match_int(&args[0], &option); + if (r < 0) { + p9_debug(P9_DEBUG_ERROR, + "integer field, but no integer?\n"); + ret = r; + continue; + } + if (option < 1) { + p9_debug(P9_DEBUG_ERROR, + "locktimeout must be a greater than zero integer.\n"); + ret = -EINVAL; + continue; + } + v9ses->session_lock_timeout = (long)option * HZ; + break; + default: continue; } diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h index 6877050384a1..3775f275ede3 100644 --- a/fs/9p/v9fs.h +++ b/fs/9p/v9fs.h @@ -116,6 +116,7 @@ struct v9fs_session_info { struct list_head slist; /* list of sessions registered with v9fs */ struct backing_dev_info bdi; struct rw_semaphore rename_sem; + long session_lock_timeout; /* retry interval for blocking locks */ };
/* cache_validity flags */ diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c index 62ce8b4a7e5f..373cc50544e9 100644 --- a/fs/9p/vfs_file.c +++ b/fs/9p/vfs_file.c @@ -154,6 +154,7 @@ static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl) uint8_t status = P9_LOCK_ERROR; int res = 0; unsigned char fl_type; + struct v9fs_session_info *v9ses;
fid = filp->private_data; BUG_ON(fid == NULL); @@ -189,6 +190,8 @@ static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl) if (IS_SETLKW(cmd)) flock.flags = P9_LOCK_FLAGS_BLOCK;
+ v9ses = v9fs_inode2v9ses(file_inode(filp)); + /* * if its a blocked request and we get P9_LOCK_BLOCKED as the status * for lock request, keep on trying @@ -202,7 +205,8 @@ static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl) break; if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd)) break; - if (schedule_timeout_interruptible(P9_LOCK_TIMEOUT) != 0) + if (schedule_timeout_interruptible(v9ses->session_lock_timeout) + != 0) break; /* * p9_client_lock_dotl overwrites flock.client_id with the