fuse: negotiate per inode DAX in FUSE_INIT

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@linux.alibaba.com>
Reviewed-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This commit is contained in:
Jeffle Xu 2021-11-25 15:05:28 +08:00 committed by Miklos Szeredi
parent 93a497b9ad
commit 2ee019fadc
3 changed files with 13 additions and 5 deletions

View File

@ -1349,7 +1349,7 @@ static bool fuse_should_enable_dax(struct inode *inode, unsigned int flags)
return true;
/* dax_mode is FUSE_DAX_INODE* */
return flags & FUSE_ATTR_DAX;
return fc->inode_dax && (flags & FUSE_ATTR_DAX);
}
void fuse_dax_inode_init(struct inode *inode, unsigned int flags)

View File

@ -780,6 +780,9 @@ struct fuse_conn {
/* Initialize security xattrs when creating a new inode */
unsigned int init_security:1;
/* Does the filesystem support per inode DAX? */
unsigned int inode_dax:1;
/** The number of requests waiting for completion */
atomic_t num_waiting;

View File

@ -1171,11 +1171,14 @@ 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) &&
flags & FUSE_MAP_ALIGNMENT &&
if (IS_ENABLED(CONFIG_FUSE_DAX)) {
if (flags & FUSE_MAP_ALIGNMENT &&
!fuse_dax_check_alignment(fc, arg->map_alignment)) {
ok = false;
}
if (flags & FUSE_HAS_INODE_DAX)
fc->inode_dax = 1;
}
if (flags & FUSE_HANDLE_KILLPRIV_V2) {
fc->handle_killpriv_v2 = 1;
fm->sb->s_flags |= SB_NOSEC;
@ -1233,6 +1236,8 @@ void fuse_send_init(struct fuse_mount *fm)
#ifdef CONFIG_FUSE_DAX
if (fm->fc->dax)
flags |= FUSE_MAP_ALIGNMENT;
if (fuse_is_inode_dax_mode(fm->fc->dax_mode))
flags |= FUSE_HAS_INODE_DAX;
#endif
if (fm->fc->auto_submounts)
flags |= FUSE_SUBMOUNTS;