From 5509826f1e548d14bb888c1cb6e3bbf23f855770 Mon Sep 17 00:00:00 2001 From: "S. Wendy Cheng" Date: Thu, 18 Jan 2007 15:56:34 -0500 Subject: [PATCH] [GFS2] Fix change nlink deadlock Bugzilla 215088 Fix deadlock in gfs2_change_nlink() while installing RHEL5 into GFS2 partition. The gfs2_rename() apparently needs block allocation for the new name (into the directory) where it requires rg locks. At the same time, while updating the nlink count for the replaced file, gfs2_change_nlink() tries to return the inode meta-data back to resource group where it needs rg locks too. Our logic doesn't allow process to acquire these locks recursively by the same process (RHEL installer) that results a BUG call. This only happens within rename code path and only if the destination file exists before the rename operation. Signed-off-by: S. Wendy Cheng Signed-off-by: Steven Whitehouse --- fs/gfs2/inode.c | 20 ++++++++++++++++---- fs/gfs2/inode.h | 1 + fs/gfs2/ops_inode.c | 25 ++++++++++++++++++++++--- 3 files changed, 39 insertions(+), 7 deletions(-) diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c index d122074c45..6bc443644c 100644 --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -281,16 +281,14 @@ out: } /** - * gfs2_change_nlink - Change nlink count on inode + * gfs2_change_nlink_i - Change nlink count on inode * @ip: The GFS2 inode * @diff: The change in the nlink count required * * Returns: errno */ - -int gfs2_change_nlink(struct gfs2_inode *ip, int diff) +int gfs2_change_nlink_i(struct gfs2_inode *ip, int diff) { - struct gfs2_sbd *sdp = ip->i_inode.i_sb->s_fs_info; struct buffer_head *dibh; u32 nlink; int error; @@ -322,6 +320,20 @@ int gfs2_change_nlink(struct gfs2_inode *ip, int diff) brelse(dibh); mark_inode_dirty(&ip->i_inode); + return error; +} + +int gfs2_change_nlink(struct gfs2_inode *ip, int diff) +{ + struct gfs2_sbd *sdp = ip->i_inode.i_sb->s_fs_info; + int error; + + /* update the nlink */ + error = gfs2_change_nlink_i(ip, diff); + if (error) + return error; + + /* return meta data block back to rg */ if (ip->i_inode.i_nlink == 0) { struct gfs2_rgrpd *rgd; struct gfs2_holder ri_gh, rg_gh; diff --git a/fs/gfs2/inode.h b/fs/gfs2/inode.h index b57f448b15..85c67cb568 100644 --- a/fs/gfs2/inode.h +++ b/fs/gfs2/inode.h @@ -40,6 +40,7 @@ int gfs2_inode_refresh(struct gfs2_inode *ip); int gfs2_dinode_dealloc(struct gfs2_inode *inode); int gfs2_change_nlink(struct gfs2_inode *ip, int diff); +int gfs2_change_nlink_i(struct gfs2_inode *ip, int diff); struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name, int is_root, struct nameidata *nd); struct inode *gfs2_createi(struct gfs2_holder *ghs, const struct qstr *name, diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c index 636dda4c7d..919e8947e7 100644 --- a/fs/gfs2/ops_inode.c +++ b/fs/gfs2/ops_inode.c @@ -553,6 +553,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry, int alloc_required; unsigned int x; int error; + struct gfs2_rgrpd *rgd; if (ndentry->d_inode) { nip = GFS2_I(ndentry->d_inode); @@ -684,12 +685,12 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry, error = gfs2_trans_begin(sdp, sdp->sd_max_dirres + al->al_rgd->rd_ri.ri_length + 4 * RES_DINODE + 4 * RES_LEAF + - RES_STATFS + RES_QUOTA, 0); + RES_STATFS + RES_QUOTA + 1, 0); if (error) goto out_ipreserv; } else { error = gfs2_trans_begin(sdp, 4 * RES_DINODE + - 5 * RES_LEAF, 0); + 5 * RES_LEAF + 1, 0); if (error) goto out_gunlock; } @@ -703,7 +704,25 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry, error = gfs2_dir_del(ndip, &ndentry->d_name); if (error) goto out_end_trans; - error = gfs2_change_nlink(nip, -1); + error = gfs2_change_nlink_i(nip, -1); + if ((!error) && (nip->i_inode.i_nlink == 0)) { + error = -EIO; + rgd = gfs2_blk2rgrpd(sdp, nip->i_num.no_addr); + if (rgd) { + struct gfs2_holder nlink_rg_gh; + if (rgd != nip->i_alloc.al_rgd) + error = gfs2_glock_nq_init( + rgd->rd_gl, LM_ST_EXCLUSIVE, + 0, &nlink_rg_gh); + else + error = 0; + if (!error) { + gfs2_unlink_di(&nip->i_inode); + if (rgd != nip->i_alloc.al_rgd) + gfs2_glock_dq_uninit(&nlink_rg_gh); + } + } + } } if (error) goto out_end_trans; -- 2.39.5