diff mbox series

[v2,15/16] gfs2: add pre-content fsnotify hook to fault

Message ID 5d4babb06516f5288a999eefb1a4dec09e775195.1723144881.git.josef@toxicpanda.com (mailing list archive)
State New
Headers show
Series fanotify: add pre-content hooks | expand

Commit Message

Josef Bacik Aug. 8, 2024, 7:27 p.m. UTC 
gfs2 takes the glock before calling into filemap fault, so add the
fsnotify hook for ->fault before we take the glock in order to avoid any
possible deadlock with the HSM.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/gfs2/file.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)
diff mbox series

Patch

diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index 08982937b5df..b841b1720b5c 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -553,9 +553,22 @@  static vm_fault_t gfs2_fault(struct vm_fault *vmf)
 	struct inode *inode = file_inode(vmf->vma->vm_file);
 	struct gfs2_inode *ip = GFS2_I(inode);
 	struct gfs2_holder gh;
+	struct file *fpin = NULL;
 	vm_fault_t ret;
 	int err;
 
+	ret = filemap_maybe_emit_fsnotify_event(vmf, &fpin);
+	if (unlikely(ret)) {
+		if (fpin) {
+			fput(fpin);
+			ret |= VM_FAULT_RETRY;
+		}
+		return ret;
+	} else if (fpin) {
+		fput(fpin);
+		return VM_FAULT_RETRY;
+	}
+
 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
 	err = gfs2_glock_nq(&gh);
 	if (err) {