diff options
| author | Remi Pommarel <repk@triplefau.lt> | 2026-05-21 11:40:30 +0200 |
|---|---|---|
| committer | Dominique Martinet <asmadeus@codewreck.org> | 2026-05-29 02:16:40 +0000 |
| commit | 7025a34eda23ddedcb1c1d585b7bdc66586434f4 (patch) | |
| tree | 458e42b580c659a59a9dde6f1940fcd7b2df9b9f /fs | |
| parent | e7b0c932b719b7f54e5e10c467b234ce36bb7ab7 (diff) | |
| download | linux-next-history-7025a34eda23ddedcb1c1d585b7bdc66586434f4.tar.gz | |
9p: Add mount option for negative dentry cache retention
Introduce a new mount option, negtimeout, for v9fs that allows users
to specify how long negative dentries are retained in the cache. The
retention time can be set in milliseconds (e.g. negtimeout=10000 for
a 10secs retention time) or a negative value (e.g. negtimeout=-1) to
keep negative entries until the buffer cache management removes them.
For consistency reasons, this option should only be used in exclusive
or read-only mount scenarios, aligning with the cache=loose usage.
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Message-ID: <b2d66500aa5a2f6540347c4aa46a4be10dd01bc6.1779355927.git.repk@triplefau.lt>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/9p/v9fs.c | 16 | ||||
| -rw-r--r-- | fs/9p/v9fs.h | 23 |
2 files changed, 28 insertions, 11 deletions
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c index be83744b75b27..3e758b66fefae 100644 --- a/fs/9p/v9fs.c +++ b/fs/9p/v9fs.c @@ -39,7 +39,7 @@ enum { * source if we rejected it as EINVAL */ Opt_source, /* Options that take integer arguments */ - Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid, + Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid, Opt_negtimeout, /* String options */ Opt_uname, Opt_remotename, Opt_cache, Opt_cachetag, /* Options that take no arguments */ @@ -93,6 +93,7 @@ const struct fs_parameter_spec v9fs_param_spec[] = { fsparam_string ("access", Opt_access), fsparam_flag ("posixacl", Opt_posixacl), fsparam_u32 ("locktimeout", Opt_locktimeout), + fsparam_s32 ("negtimeout", Opt_negtimeout), /* client options */ fsparam_u32 ("msize", Opt_msize), @@ -159,6 +160,9 @@ int v9fs_show_options(struct seq_file *m, struct dentry *root) from_kgid_munged(&init_user_ns, v9ses->dfltgid)); if (v9ses->afid != ~0) seq_printf(m, ",afid=%u", v9ses->afid); + if (v9ses->flags & V9FS_NDENTRY_TIMEOUT_SET) + seq_printf(m, ",negtimeout=%d", + (int)v9ses->ndentry_timeout_ms); if (strcmp(v9ses->uname, V9FS_DEFUSER) != 0) seq_printf(m, ",uname=%s", v9ses->uname); if (strcmp(v9ses->aname, V9FS_DEFANAME) != 0) @@ -337,6 +341,16 @@ int v9fs_parse_param(struct fs_context *fc, struct fs_parameter *param) session_opts->session_lock_timeout = (long)result.uint_32 * HZ; break; + case Opt_negtimeout: + session_opts->flags |= V9FS_NDENTRY_TIMEOUT_SET; + if (result.int_32 < 0) { + session_opts->ndentry_timeout_ms = + NDENTRY_TIMEOUT_NEVER; + } else { + session_opts->ndentry_timeout_ms = result.int_32; + } + break; + /* Options for client */ case Opt_msize: if (result.uint_32 < 4096) { diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h index e630c5111d749..a462bcbfc7da4 100644 --- a/fs/9p/v9fs.h +++ b/fs/9p/v9fs.h @@ -24,6 +24,8 @@ * @V9FS_ACCESS_ANY: use a single attach for all users * @V9FS_ACCESS_MASK: bit mask of different ACCESS options * @V9FS_POSIX_ACL: POSIX ACLs are enforced + * @V9FS_NDENTRY_TIMEOUT_SET: Has negative dentry timeout retention time been + * overridden by negtimeout mount option * * Session flags reflect options selected by users at mount time */ @@ -34,16 +36,17 @@ #define V9FS_ACL_MASK V9FS_POSIX_ACL enum p9_session_flags { - V9FS_PROTO_2000U = 0x01, - V9FS_PROTO_2000L = 0x02, - V9FS_ACCESS_SINGLE = 0x04, - V9FS_ACCESS_USER = 0x08, - V9FS_ACCESS_CLIENT = 0x10, - V9FS_POSIX_ACL = 0x20, - V9FS_NO_XATTR = 0x40, - V9FS_IGNORE_QV = 0x80, /* ignore qid.version for cache hints */ - V9FS_DIRECT_IO = 0x100, - V9FS_SYNC = 0x200 + V9FS_PROTO_2000U = 0x01, + V9FS_PROTO_2000L = 0x02, + V9FS_ACCESS_SINGLE = 0x04, + V9FS_ACCESS_USER = 0x08, + V9FS_ACCESS_CLIENT = 0x10, + V9FS_POSIX_ACL = 0x20, + V9FS_NO_XATTR = 0x40, + V9FS_IGNORE_QV = 0x80, /* ignore qid.version for cache hints */ + V9FS_DIRECT_IO = 0x100, + V9FS_SYNC = 0x200, + V9FS_NDENTRY_TIMEOUT_SET = 0x400, }; /** |