gfs2: Fix freeze consistency check in gfs2_trans_add_meta

Function gfs2_trans_add_meta() checks for the SDF_FROZEN flag to make
sure that no buffers are added to a transaction while the filesystem is
frozen.  With the recent freeze/thaw rework, the SDF_FROZEN flag is
cleared after thaw_super() is called, which is sufficient for
serializing freeze/thaw.

However, other filesystem operations started after thaw_super() may now
be calling gfs2_trans_add_meta() before the SDF_FROZEN flag is cleared,
which will trigger the SDF_FROZEN check in gfs2_trans_add_meta().  Fix
that by checking the s_writers.frozen state instead.

In addition, make sure not to call gfs2_assert_withdraw() with the
sd_log_lock spin lock held.  Check for a withdrawn filesystem before
checking for a frozen filesystem, and don't pin/add buffers to the
current transaction in case of a failure in either case.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
This commit is contained in:
Andreas Gruenbacher 2023-08-04 22:17:32 +02:00
parent 94c76955e8
commit 2cbd80642b

View file

@ -230,9 +230,11 @@ void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
{
struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
struct super_block *sb = sdp->sd_vfs;
struct gfs2_bufdata *bd;
struct gfs2_meta_header *mh;
struct gfs2_trans *tr = current->journal_info;
bool withdraw = false;
lock_buffer(bh);
if (buffer_pinned(bh)) {
@ -266,13 +268,15 @@ void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
(unsigned long long)bd->bd_bh->b_blocknr);
BUG();
}
if (unlikely(test_bit(SDF_FROZEN, &sdp->sd_flags))) {
fs_info(sdp, "GFS2:adding buf while frozen\n");
gfs2_assert_withdraw(sdp, 0);
}
if (unlikely(gfs2_withdrawn(sdp))) {
fs_info(sdp, "GFS2:adding buf while withdrawn! 0x%llx\n",
(unsigned long long)bd->bd_bh->b_blocknr);
goto out_unlock;
}
if (unlikely(sb->s_writers.frozen == SB_FREEZE_COMPLETE)) {
fs_info(sdp, "GFS2:adding buf while frozen\n");
withdraw = true;
goto out_unlock;
}
gfs2_pin(sdp, bd->bd_bh);
mh->__pad0 = cpu_to_be64(0);
@ -281,6 +285,8 @@ void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
tr->tr_num_buf_new++;
out_unlock:
gfs2_log_unlock(sdp);
if (withdraw)
gfs2_assert_withdraw(sdp, 0);
out:
unlock_buffer(bh);
}