@@ -393,12 +393,10 @@ static void buf_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
struct gfs2_meta_header *mh;
struct gfs2_trans *tr;
- lock_buffer(bd->bd_bh);
- gfs2_log_lock(sdp);
tr = current->journal_info;
tr->tr_touched = 1;
if (!list_empty(&bd->bd_list))
- goto out;
+ return;
set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
gfs2_meta_check(sdp, bd->bd_bh);
@@ -409,9 +407,6 @@ static void buf_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
sdp->sd_log_num_buf++;
list_add(&bd->bd_list, &sdp->sd_log_le_buf);
tr->tr_num_buf_new++;
-out:
- gfs2_log_unlock(sdp);
- unlock_buffer(bd->bd_bh);
}
static void gfs2_check_magic(struct buffer_head *bh)
@@ -772,12 +767,10 @@ static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
struct address_space *mapping = bd->bd_bh->b_page->mapping;
struct gfs2_inode *ip = GFS2_I(mapping->host);
- lock_buffer(bd->bd_bh);
- gfs2_log_lock(sdp);
if (tr)
tr->tr_touched = 1;
if (!list_empty(&bd->bd_list))
- goto out;
+ return;
set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
if (gfs2_is_jdata(ip)) {
@@ -788,9 +781,6 @@ static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
} else {
list_add_tail(&bd->bd_list, &sdp->sd_log_le_ordered);
}
-out:
- gfs2_log_unlock(sdp);
- unlock_buffer(bd->bd_bh);
}
/**
@@ -151,14 +151,22 @@ void gfs2_trans_add_bh(struct gfs2_glock *gl, struct buffer_head *bh, int meta)
struct gfs2_sbd *sdp = gl->gl_sbd;
struct gfs2_bufdata *bd;
+ lock_buffer(bh);
+ gfs2_log_lock(sdp);
bd = bh->b_private;
if (bd)
gfs2_assert(sdp, bd->bd_gl == gl);
else {
+ gfs2_log_unlock(sdp);
+ unlock_buffer(bh);
gfs2_attach_bufdata(gl, bh, meta);
bd = bh->b_private;
+ lock_buffer(bh);
+ gfs2_log_lock(sdp);
}
lops_add(sdp, bd);
+ gfs2_log_unlock(sdp);
+ unlock_buffer(bh);
}
void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
This is a note to let you know that I have just added a patch titled GFS2: Test bufdata with buffer locked and gfs2_log_lock held to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Herton ------ From 98ab5107c3429252fb5ca097dcf6c8e1109bdd90 Mon Sep 17 00:00:00 2001 From: Benjamin Marzinski <bmarzins@redhat.com> Date: Wed, 7 Nov 2012 00:38:06 -0600 Subject: [PATCH] GFS2: Test bufdata with buffer locked and gfs2_log_lock held commit 96e5d1d3adf56f1c7eeb07258f6a1a0a7ae9c489 upstream. In gfs2_trans_add_bh(), gfs2 was testing if a there was a bd attached to the buffer without having the gfs2_log_lock held. It was then assuming it would stay attached for the rest of the function. However, without either the log lock being held of the buffer locked, __gfs2_ail_flush() could detach bd at any time. This patch moves the locking before the test. If there isn't a bd already attached, gfs2 can safely allocate one and attach it before locking. There is no way that the newly allocated bd could be on the ail list, and thus no way for __gfs2_ail_flush() to detach it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com> Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> --- fs/gfs2/lops.c | 14 ++------------ fs/gfs2/trans.c | 8 ++++++++ 2 files changed, 10 insertions(+), 12 deletions(-) -- 1.7.9.5