GFS2: Prevent delete work from occurring on glocks used for create
authorBob Peterson <rpeterso@redhat.com>
Mon, 7 Dec 2015 22:24:27 +0000 (16:24 -0600)
committerBob Peterson <rpeterso@redhat.com>
Tue, 15 Mar 2016 14:46:37 +0000 (10:46 -0400)
This patch tries to prevent delete work (queued via iopen callback)
from executing if the glock is currently being used to create
a new inode.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
fs/gfs2/glock.c
fs/gfs2/incore.h
fs/gfs2/inode.c

index 5788ebff716a43cdbb68c345de26749ca7c4571d..7f0257309b3e8a5ef3f180b400fe5e39f0143e65 100644 (file)
@@ -572,6 +572,12 @@ static void delete_work_func(struct work_struct *work)
        struct inode *inode;
        u64 no_addr = gl->gl_name.ln_number;
 
+       /* If someone's using this glock to create a new dinode, the block must
+          have been freed by another node, then re-used, in which case our
+          iopen callback is too late after the fact. Ignore it. */
+       if (test_bit(GLF_INODE_CREATING, &gl->gl_flags))
+               goto out;
+
        ip = gl->gl_object;
        /* Note: Unsafe to dereference ip as we don't hold right refs/locks */
 
@@ -583,6 +589,7 @@ static void delete_work_func(struct work_struct *work)
                d_prune_aliases(inode);
                iput(inode);
        }
+out:
        gfs2_glock_put(gl);
 }
 
index 845fb09cc60668037b67edf243c2ab05c6f9e6e4..a6a3389a07fc67187288e5bb82a3b19d4996bf37 100644 (file)
@@ -328,6 +328,7 @@ enum {
        GLF_LRU                         = 13,
        GLF_OBJECT                      = 14, /* Used only for tracing */
        GLF_BLOCKING                    = 15,
+       GLF_INODE_CREATING              = 16, /* Inode creation occurring */
 };
 
 struct gfs2_glock {
index 3e94400d587c4e1efdea6afee130b7b35c0a16f5..95a914524a39757585eeeec9357aa57cfeb0c5d7 100644 (file)
@@ -592,7 +592,7 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
        struct inode *inode = NULL;
        struct gfs2_inode *dip = GFS2_I(dir), *ip;
        struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
-       struct gfs2_glock *io_gl;
+       struct gfs2_glock *io_gl = NULL;
        int error, free_vfs_inode = 1;
        u32 aflags = 0;
        unsigned blocks = 1;
@@ -729,6 +729,8 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
        if (error)
                goto fail_gunlock2;
 
+       BUG_ON(test_and_set_bit(GLF_INODE_CREATING, &io_gl->gl_flags));
+
        error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
        if (error)
                goto fail_gunlock2;
@@ -771,12 +773,15 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
        }
        gfs2_glock_dq_uninit(ghs);
        gfs2_glock_dq_uninit(ghs + 1);
+       clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
        return error;
 
 fail_gunlock3:
        gfs2_glock_dq_uninit(&ip->i_iopen_gh);
        gfs2_glock_put(io_gl);
 fail_gunlock2:
+       if (io_gl)
+               clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
        gfs2_glock_dq_uninit(ghs + 1);
 fail_free_inode:
        if (ip->i_gl)