| Message ID | 20250214-fuse-link-eperm-v1-1-8c241d987008@codeconstruct.com.au (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | fuse: Return EPERM rather than ENOSYS from link() | expand |
On Fri, 14 Feb 2025 at 02:18, Matt Johnston <matt@codeconstruct.com.au> wrote: > > link() is documented to return EPERM when a filesystem doesn't support > the operation, return that instead. Applied, thanks. Also added the following optimization patch if link is not supported. Thanks, Miklos From 150b838b03e887f4e5ffdadcffafef698e34c619 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi <mszeredi@redhat.com> Date: Fri, 14 Feb 2025 11:00:53 +0100 Subject: [PATCH] fuse: optmize missing FUSE_LINK support If filesystem doesn't support FUSE_LINK (i.e. returns -ENOSYS), then remember this and next time return immediately, without incurring the overhead of a round trip to the server. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> --- fs/fuse/dir.c | 9 ++++++++- fs/fuse/fuse_i.h | 3 +++ 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index f07ccaefd1ec..589e88822368 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -1123,6 +1123,9 @@ static int fuse_link(struct dentry *entry, struct inode *newdir, struct fuse_mount *fm = get_fuse_mount(inode); FUSE_ARGS(args); + if (fm->fc->no_link) + goto out; + memset(&inarg, 0, sizeof(inarg)); inarg.oldnodeid = get_node_id(inode); args.opcode = FUSE_LINK; @@ -1138,7 +1141,11 @@ static int fuse_link(struct dentry *entry, struct inode *newdir, fuse_invalidate_attr(inode); if (err == -ENOSYS) - err = -EPERM; + fm->fc->no_link = 1; +out: + if (fm->fc->no_link) + return -EPERM; + return err; } diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index fee96fe7887b..3ad5d4b8f7c5 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -867,6 +867,9 @@ struct fuse_conn { /* Use pages instead of pointer for kernel I/O */ unsigned int use_pages_for_kvec_io:1; + /* Is link not implemented by fs? */ + unsigned int no_link:1; + /* Use io_uring for communication */ unsigned int io_uring;
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 198862b086ff7bad4007ec2f3200377d12a78385..f07ccaefd1ecfe02b806c30fa9edc6f481260ee8 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -1137,6 +1137,8 @@ static int fuse_link(struct dentry *entry, struct inode *newdir, else if (err == -EINTR) fuse_invalidate_attr(inode); + if (err == -ENOSYS) + err = -EPERM; return err; }
link() is documented to return EPERM when a filesystem doesn't support the operation, return that instead. Link: https://github.com/libfuse/libfuse/issues/925 Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> --- fs/fuse/dir.c | 2 ++ 1 file changed, 2 insertions(+) --- base-commit: 68763b29e0a6441f57f9ee652bbf8e7bc59183e5 change-id: 20250214-fuse-link-eperm-544b081eac34 Best regards,