diff mbox series

[v3,14/16] bcachefs: add pre-content fsnotify hook to fault

Message ID b3fc6d63e23626033ff2764a82d3e20a059ac8a4.1723228772.git.josef@toxicpanda.com (mailing list archive)
State Superseded, archived
Headers show
Series fanotify: add pre-content hooks | expand

Commit Message

Josef Bacik Aug. 9, 2024, 6:44 p.m. UTC
bcachefs has its own locking around filemap_fault, so we have to make
sure we do the fsnotify hook before the locking.  Add the check to emit
the event before the locking and return VM_FAULT_RETRY to retrigger the
fault once the event has been emitted.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/bcachefs/fs-io-pagecache.c | 4 ++++
 1 file changed, 4 insertions(+)

Comments

Kent Overstreet Aug. 10, 2024, 8:06 p.m. UTC | #1
On Fri, Aug 09, 2024 at 02:44:22PM GMT, Josef Bacik wrote:
> bcachefs has its own locking around filemap_fault, so we have to make
> sure we do the fsnotify hook before the locking.  Add the check to emit
> the event before the locking and return VM_FAULT_RETRY to retrigger the
> fault once the event has been emitted.
> 
> Signed-off-by: Josef Bacik <josef@toxicpanda.com>

Acked-by: Kent Overstreet <kent.overstreet@linux.dev>

Josef, are you testing this on bcachefs as well? I'll get you an account
for my CI if you want it (which has automated tests for more than
bcachefs).

> ---
>  fs/bcachefs/fs-io-pagecache.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/fs/bcachefs/fs-io-pagecache.c b/fs/bcachefs/fs-io-pagecache.c
> index a9cc5cad9cc9..1fa1f1ac48c8 100644
> --- a/fs/bcachefs/fs-io-pagecache.c
> +++ b/fs/bcachefs/fs-io-pagecache.c
> @@ -570,6 +570,10 @@ vm_fault_t bch2_page_fault(struct vm_fault *vmf)
>  	if (fdm == mapping)
>  		return VM_FAULT_SIGBUS;
>  
> +	ret = filemap_maybe_emit_fsnotify_event(vmf);
> +	if (unlikely(ret))
> +		return ret;
> +
>  	/* Lock ordering: */
>  	if (fdm > mapping) {
>  		struct bch_inode_info *fdm_host = to_bch_ei(fdm->host);
> -- 
> 2.43.0
>
diff mbox series

Patch

diff --git a/fs/bcachefs/fs-io-pagecache.c b/fs/bcachefs/fs-io-pagecache.c
index a9cc5cad9cc9..1fa1f1ac48c8 100644
--- a/fs/bcachefs/fs-io-pagecache.c
+++ b/fs/bcachefs/fs-io-pagecache.c
@@ -570,6 +570,10 @@  vm_fault_t bch2_page_fault(struct vm_fault *vmf)
 	if (fdm == mapping)
 		return VM_FAULT_SIGBUS;
 
+	ret = filemap_maybe_emit_fsnotify_event(vmf);
+	if (unlikely(ret))
+		return ret;
+
 	/* Lock ordering: */
 	if (fdm > mapping) {
 		struct bch_inode_info *fdm_host = to_bch_ei(fdm->host);