GFS2: Cache dir hash table in a contiguous buffer

[pandora-kernel.git] / fs / gfs2 / super.c

diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index ed540e7..b7beadd 100644 (file)
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -757,13 +757,17 @@ static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
        struct timespec atime;
        struct gfs2_dinode *di;
        int ret = -EAGAIN;
+       int unlock_required = 0;
 
        /* Skip timestamp update, if this is from a memalloc */
        if (current->flags & PF_MEMALLOC)
                goto do_flush;
-       ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
-       if (ret)
-               goto do_flush;
+       if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
+               ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
+               if (ret)
+                       goto do_flush;
+               unlock_required = 1;
+       }
        ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
        if (ret)
                goto do_unlock;
@@ -780,7 +784,8 @@ static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
        }
        gfs2_trans_end(sdp);
 do_unlock:
-       gfs2_glock_dq_uninit(&gh);
+       if (unlock_required)
+               gfs2_glock_dq_uninit(&gh);
 do_flush:
        if (wbc->sync_mode == WB_SYNC_ALL)
                gfs2_log_flush(GFS2_SB(inode), ip->i_gl);
@@ -1427,7 +1432,20 @@ out:
        return error;
 }
 
-/*
+/**
+ * gfs2_evict_inode - Remove an inode from cache
+ * @inode: The inode to evict
+ *
+ * There are three cases to consider:
+ * 1. i_nlink == 0, we are final opener (and must deallocate)
+ * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
+ * 3. i_nlink > 0
+ *
+ * If the fs is read only, then we have to treat all cases as per #3
+ * since we are unable to do any deallocation. The inode will be
+ * deallocated by the next read/write node to attempt an allocation
+ * in the same resource group
+ *
  * We have to (at the moment) hold the inodes main lock to cover
  * the gap between unlocking the shared lock on the iopen lock and
  * taking the exclusive lock. I'd rather do a shared -> exclusive
@@ -1470,6 +1488,8 @@ static void gfs2_evict_inode(struct inode *inode)
        if (error)
                goto out_truncate;
 
+       /* Case 1 starts here */
+
        if (S_ISDIR(inode->i_mode) &&
            (ip->i_diskflags & GFS2_DIF_EXHASH)) {
                error = gfs2_dir_exhash_dealloc(ip);
@@ -1493,13 +1513,16 @@ static void gfs2_evict_inode(struct inode *inode)
        goto out_unlock;
 
 out_truncate:
+       /* Case 2 starts here */
        error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
        if (error)
                goto out_unlock;
-       gfs2_final_release_pages(ip);
+       /* Needs to be done before glock release & also in a transaction */
+       truncate_inode_pages(&inode->i_data, 0);
        gfs2_trans_end(sdp);
 
 out_unlock:
+       /* Error path for case 1 */
        if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags))
                gfs2_glock_dq(&ip->i_iopen_gh);
        gfs2_holder_uninit(&ip->i_iopen_gh);
@@ -1507,9 +1530,10 @@ out_unlock:
        if (error && error != GLR_TRYFAILED && error != -EROFS)
                fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
 out:
+       /* Case 3 starts here */
        truncate_inode_pages(&inode->i_data, 0);
        end_writeback(inode);
-
+       gfs2_dir_hash_inval(ip);
        ip->i_gl->gl_object = NULL;
        gfs2_glock_add_to_lru(ip->i_gl);
        gfs2_glock_put(ip->i_gl);