gfs2: Replace GIF_DEFER_DELETE with GLF_DEFER_DELETE

Having this flag attached to the iopen glock instead of the inode is
much simpler; it eliminates a protential weird race in gfs2_try_evict().

Signed-off-by: Andreas Gruenbacher <[email protected]>

Author: Andreas Gruenbacher

fs/gfs2/glock.c

@@ -991,15 +991,15 @@ static void gfs2_try_evict(struct gfs2_glock *gl)
 		}
 	}
 	if (ip) {
-		set_bit(GIF_DEFER_DELETE, &ip->i_flags);
+		set_bit(GLF_DEFER_DELETE, &gl->gl_flags);
 		d_prune_aliases(&ip->i_inode);
 		iput(&ip->i_inode);
+		clear_bit(GLF_DEFER_DELETE, &gl->gl_flags);
 
 		/* If the inode was evicted, gl->gl_object will now be NULL. */
 		spin_lock(&gl->gl_lockref.lock);
 		ip = gl->gl_object;
 		if (ip) {
-			clear_bit(GIF_DEFER_DELETE, &ip->i_flags);
 			if (!igrab(&ip->i_inode))
 				ip = NULL;
 		}
@@ -2350,6 +2350,8 @@ static const char *gflags2str(char *buf, const struct gfs2_glock *gl)
 		*p++ = 'e';
 	if (test_bit(GLF_VERIFY_DELETE, gflags))
 		*p++ = 'E';
+	if (test_bit(GLF_DEFER_DELETE, gflags))
+		*p++ = 's';
 	*p = 0;
 	return buf;
 }

fs/gfs2/incore.h

@@ -331,6 +331,7 @@ enum {
 	GLF_TRY_TO_EVICT		= 17, /* iopen glocks only */
 	GLF_VERIFY_DELETE		= 18, /* iopen glocks only */
 	GLF_PENDING_REPLY		= 19,
+	GLF_DEFER_DELETE		= 20, /* iopen glocks only */
 };
 
 struct gfs2_glock {
@@ -377,7 +378,6 @@ enum {
 	GIF_SW_PAGED		= 3,
 	GIF_FREE_VFS_INODE      = 5,
 	GIF_GLOP_PENDING	= 6,
-	GIF_DEFER_DELETE	= 7,
 };
 
 struct gfs2_inode {

fs/gfs2/super.c

@@ -1329,7 +1329,8 @@ static enum evict_behavior evict_should_delete(struct inode *inode,
 	if (unlikely(test_bit(GIF_ALLOC_FAILED, &ip->i_flags)))
 		goto should_delete;
 
-	if (test_bit(GIF_DEFER_DELETE, &ip->i_flags))
+	if (gfs2_holder_initialized(&ip->i_iopen_gh) &&
+	    test_bit(GLF_DEFER_DELETE, &ip->i_iopen_gh.gh_gl->gl_flags))
 		return EVICT_SHOULD_DEFER_DELETE;
 
 	/* Deletes should never happen under memory pressure anymore.  */

fs/gfs2/trace_gfs2.h

@@ -64,7 +64,8 @@
 	{(1UL << GLF_INSTANTIATE_NEEDED),	"n" },		\
 	{(1UL << GLF_INSTANTIATE_IN_PROG),	"N" },		\
 	{(1UL << GLF_TRY_TO_EVICT),		"e" },		\
-	{(1UL << GLF_VERIFY_DELETE),		"E" })
+	{(1UL << GLF_VERIFY_DELETE),		"E" },		\
+	{(1UL << GLF_DEFER_DELETE),		"s" })
 
 #ifndef NUMPTY
 #define NUMPTY