Among the FUSE_INIT phase, client shall advertise per inode DAX if it's
mounted with "dax=inode". Then server is aware that client is in per
inode DAX mode, and will construct per-inode DAX attribute accordingly.
Server shall also advertise support for per inode DAX. If server doesn't
support it while client is mounted with "dax=inode", client will
silently fallback to "dax=never" since "dax=inode" is advisory only.
Signed-off-by: Jeffle Xu <jefflexu@xxxxxxxxxxxxxxxxx>
---
fs/fuse/dax.c | 2 +-
fs/fuse/fuse_i.h | 3 +++
fs/fuse/inode.c | 16 +++++++++++++---
3 files changed, 17 insertions(+), 4 deletions(-)
diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
index 8a328fb20dcb..c8ee601b94b8 100644
--- a/fs/fuse/dax.c
+++ b/fs/fuse/dax.c
@@ -1350,7 +1350,7 @@ static bool fuse_should_enable_dax(struct inode *inode, unsigned int flags)
return true;
/* dax_mode is FUSE_DAX_INODE or FUSE_DAX_NONE */
- return flags & FUSE_ATTR_DAX;
+ return fc->inode_dax && (flags & FUSE_ATTR_DAX);
}
void fuse_dax_inode_init(struct inode *inode, unsigned int flags)
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 055b39430540..58e54b5a4d65 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -777,6 +777,9 @@ struct fuse_conn {
/* Propagate syncfs() to server */
unsigned int sync_fs:1;
+ /* Does the filesystem support per inode DAX? */
+ unsigned int inode_dax:1;
+
/** The number of requests waiting for completion */
atomic_t num_waiting;
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index acba14002d04..0512d8cb36c3 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -1136,11 +1136,19 @@ static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args,
min_t(unsigned int, fc->max_pages_limit,
max_t(unsigned int, arg->max_pages, 1));
}
- if (IS_ENABLED(CONFIG_FUSE_DAX) &&
- arg->flags & FUSE_MAP_ALIGNMENT &&
+#ifdef CONFIG_FUSE_DAX
+ if ((arg->flags & FUSE_HAS_INODE_DAX) &&
+ fuse_is_inode_dax_mode(fc->dax_mode)) {
+ fc->inode_dax = 1;
+ }
+ if (arg->flags & FUSE_MAP_ALIGNMENT &&
!fuse_dax_check_alignment(fc, arg->map_alignment)) {
- ok = false;
+ if (fuse_is_inode_dax_mode(fc->dax_mode))
+ fc->inode_dax = 0;
+ else
+ ok = false;
}
+#endif
if (arg->flags & FUSE_HANDLE_KILLPRIV_V2) {
fc->handle_killpriv_v2 = 1;
fm->sb->s_flags |= SB_NOSEC;
@@ -1194,6 +1202,8 @@ void fuse_send_init(struct fuse_mount *fm)
#ifdef CONFIG_FUSE_DAX
if (fm->fc->dax)
ia->in.flags |= FUSE_MAP_ALIGNMENT;
+ if (fuse_is_inode_dax_mode(fm->fc->dax_mode))
+ ia->in.flags |= FUSE_HAS_INODE_DAX;
#endif
if (fm->fc->auto_submounts)
ia->in.flags |= FUSE_SUBMOUNTS;
--
2.27.0
