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authorSteven Whitehouse <swhiteho@redhat.com>2010-08-11 09:37:53 +0100
committerSteven Whitehouse <swhiteho@redhat.com>2010-09-20 11:18:16 +0100
commitff8f33c8b30d7b7efdcf2548c7f6e64db6a89b29 (patch)
treea21bad4d2b48f743dd96277b1c966c35aefe1ce2 /fs/gfs2/bmap.c
parent2422084a94fcd5038406261b331672a13c92c050 (diff)
GFS2: New truncate sequence
This updates GFS2's truncate code to use the new truncate sequence correctly. This is a stepping stone to being able to remove ip->i_disksize in favour of using i_size everywhere now that the two sizes are always identical. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'fs/gfs2/bmap.c')
-rw-r--r--fs/gfs2/bmap.c247
1 files changed, 119 insertions, 128 deletions
diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index 6f482809d1a3..20b971ad4973 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -50,7 +50,7 @@ struct strip_mine {
* @ip: the inode
* @dibh: the dinode buffer
* @block: the block number that was allocated
- * @private: any locked page held by the caller process
+ * @page: The (optional) page. This is looked up if @page is NULL
*
* Returns: errno
*/
@@ -109,8 +109,7 @@ static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh,
/**
* gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big
* @ip: The GFS2 inode to unstuff
- * @unstuffer: the routine that handles unstuffing a non-zero length file
- * @private: private data for the unstuffer
+ * @page: The (optional) page. This is looked up if the @page is NULL
*
* This routine unstuffs a dinode and returns it to a "normal" state such
* that the height can be grown in the traditional way.
@@ -885,83 +884,14 @@ out:
}
/**
- * do_grow - Make a file look bigger than it is
- * @ip: the inode
- * @size: the size to set the file to
- *
- * Called with an exclusive lock on @ip.
- *
- * Returns: errno
- */
-
-static int do_grow(struct gfs2_inode *ip, u64 size)
-{
- struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
- struct gfs2_alloc *al;
- struct buffer_head *dibh;
- int error;
-
- al = gfs2_alloc_get(ip);
- if (!al)
- return -ENOMEM;
-
- error = gfs2_quota_lock_check(ip);
- if (error)
- goto out;
-
- al->al_requested = sdp->sd_max_height + RES_DATA;
-
- error = gfs2_inplace_reserve(ip);
- if (error)
- goto out_gunlock_q;
-
- error = gfs2_trans_begin(sdp,
- sdp->sd_max_height + al->al_rgd->rd_length +
- RES_JDATA + RES_DINODE + RES_STATFS + RES_QUOTA, 0);
- if (error)
- goto out_ipres;
-
- error = gfs2_meta_inode_buffer(ip, &dibh);
- if (error)
- goto out_end_trans;
-
- if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
- if (gfs2_is_stuffed(ip)) {
- error = gfs2_unstuff_dinode(ip, NULL);
- if (error)
- goto out_brelse;
- }
- }
-
- ip->i_disksize = size;
- ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
- gfs2_trans_add_bh(ip->i_gl, dibh, 1);
- gfs2_dinode_out(ip, dibh->b_data);
-
-out_brelse:
- brelse(dibh);
-out_end_trans:
- gfs2_trans_end(sdp);
-out_ipres:
- gfs2_inplace_release(ip);
-out_gunlock_q:
- gfs2_quota_unlock(ip);
-out:
- gfs2_alloc_put(ip);
- return error;
-}
-
-
-/**
* gfs2_block_truncate_page - Deal with zeroing out data for truncate
*
* This is partly borrowed from ext3.
*/
-static int gfs2_block_truncate_page(struct address_space *mapping)
+static int gfs2_block_truncate_page(struct address_space *mapping, loff_t from)
{
struct inode *inode = mapping->host;
struct gfs2_inode *ip = GFS2_I(inode);
- loff_t from = inode->i_size;
unsigned long index = from >> PAGE_CACHE_SHIFT;
unsigned offset = from & (PAGE_CACHE_SIZE-1);
unsigned blocksize, iblock, length, pos;
@@ -1023,9 +953,11 @@ unlock:
return err;
}
-static int trunc_start(struct gfs2_inode *ip, u64 size)
+static int trunc_start(struct inode *inode, u64 oldsize, u64 newsize)
{
- struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_sbd *sdp = GFS2_SB(inode);
+ struct address_space *mapping = inode->i_mapping;
struct buffer_head *dibh;
int journaled = gfs2_is_jdata(ip);
int error;
@@ -1039,31 +971,27 @@ static int trunc_start(struct gfs2_inode *ip, u64 size)
if (error)
goto out;
+ gfs2_trans_add_bh(ip->i_gl, dibh, 1);
+
if (gfs2_is_stuffed(ip)) {
- u64 dsize = size + sizeof(struct gfs2_dinode);
- ip->i_disksize = size;
- ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
- gfs2_trans_add_bh(ip->i_gl, dibh, 1);
- gfs2_dinode_out(ip, dibh->b_data);
- if (dsize > dibh->b_size)
- dsize = dibh->b_size;
- gfs2_buffer_clear_tail(dibh, dsize);
- error = 1;
+ gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + newsize);
} else {
- if (size & (u64)(sdp->sd_sb.sb_bsize - 1))
- error = gfs2_block_truncate_page(ip->i_inode.i_mapping);
-
- if (!error) {
- ip->i_disksize = size;
- ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
- ip->i_diskflags |= GFS2_DIF_TRUNC_IN_PROG;
- gfs2_trans_add_bh(ip->i_gl, dibh, 1);
- gfs2_dinode_out(ip, dibh->b_data);
+ if (newsize & (u64)(sdp->sd_sb.sb_bsize - 1)) {
+ error = gfs2_block_truncate_page(mapping, newsize);
+ if (error)
+ goto out_brelse;
}
+ ip->i_diskflags |= GFS2_DIF_TRUNC_IN_PROG;
}
- brelse(dibh);
+ i_size_write(inode, newsize);
+ ip->i_disksize = newsize;
+ ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
+ gfs2_dinode_out(ip, dibh->b_data);
+ truncate_pagecache(inode, oldsize, newsize);
+out_brelse:
+ brelse(dibh);
out:
gfs2_trans_end(sdp);
return error;
@@ -1143,86 +1071,149 @@ out:
/**
* do_shrink - make a file smaller
- * @ip: the inode
- * @size: the size to make the file
- * @truncator: function to truncate the last partial block
+ * @inode: the inode
+ * @oldsize: the current inode size
+ * @newsize: the size to make the file
*
- * Called with an exclusive lock on @ip.
+ * Called with an exclusive lock on @inode. The @size must
+ * be equal to or smaller than the current inode size.
*
* Returns: errno
*/
-static int do_shrink(struct gfs2_inode *ip, u64 size)
+static int do_shrink(struct inode *inode, u64 oldsize, u64 newsize)
{
+ struct gfs2_inode *ip = GFS2_I(inode);
int error;
- error = trunc_start(ip, size);
+ error = trunc_start(inode, oldsize, newsize);
if (error < 0)
return error;
- if (error > 0)
+ if (gfs2_is_stuffed(ip))
return 0;
- error = trunc_dealloc(ip, size);
- if (!error)
+ error = trunc_dealloc(ip, newsize);
+ if (error == 0)
error = trunc_end(ip);
return error;
}
-static int do_touch(struct gfs2_inode *ip, u64 size)
+void gfs2_trim_blocks(struct inode *inode)
{
- struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
+ u64 size = inode->i_size;
+ int ret;
+
+ ret = do_shrink(inode, size, size);
+ WARN_ON(ret != 0);
+}
+
+/**
+ * do_grow - Touch and update inode size
+ * @inode: The inode
+ * @size: The new size
+ *
+ * This function updates the timestamps on the inode and
+ * may also increase the size of the inode. This function
+ * must not be called with @size any smaller than the current
+ * inode size.
+ *
+ * Although it is not strictly required to unstuff files here,
+ * earlier versions of GFS2 have a bug in the stuffed file reading
+ * code which will result in a buffer overrun if the size is larger
+ * than the max stuffed file size. In order to prevent this from
+ * occuring, such files are unstuffed, but in other cases we can
+ * just update the inode size directly.
+ *
+ * Returns: 0 on success, or -ve on error
+ */
+
+static int do_grow(struct inode *inode, u64 size)
+{
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_sbd *sdp = GFS2_SB(inode);
struct buffer_head *dibh;
+ struct gfs2_alloc *al = NULL;
int error;
- error = gfs2_trans_begin(sdp, RES_DINODE, 0);
+ if (gfs2_is_stuffed(ip) &&
+ (size > (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)))) {
+ al = gfs2_alloc_get(ip);
+ if (al == NULL)
+ return -ENOMEM;
+
+ error = gfs2_quota_lock_check(ip);
+ if (error)
+ goto do_grow_alloc_put;
+
+ al->al_requested = 1;
+ error = gfs2_inplace_reserve(ip);
+ if (error)
+ goto do_grow_qunlock;
+ }
+
+ error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);
if (error)
- return error;
+ goto do_grow_release;
- down_write(&ip->i_rw_mutex);
+ if (al) {
+ error = gfs2_unstuff_dinode(ip, NULL);
+ if (error)
+ goto do_end_trans;
+ }
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
- goto do_touch_out;
+ goto do_end_trans;
+ i_size_write(inode, size);
+ ip->i_disksize = size;
ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
brelse(dibh);
-do_touch_out:
- up_write(&ip->i_rw_mutex);
+do_end_trans:
gfs2_trans_end(sdp);
+do_grow_release:
+ if (al) {
+ gfs2_inplace_release(ip);
+do_grow_qunlock:
+ gfs2_quota_unlock(ip);
+do_grow_alloc_put:
+ gfs2_alloc_put(ip);
+ }
return error;
}
/**
- * gfs2_truncatei - make a file a given size
- * @ip: the inode
- * @size: the size to make the file
- * @truncator: function to truncate the last partial block
+ * gfs2_setattr_size - make a file a given size
+ * @inode: the inode
+ * @newsize: the size to make the file
*
- * The file size can grow, shrink, or stay the same size.
+ * The file size can grow, shrink, or stay the same size. This
+ * is called holding i_mutex and an exclusive glock on the inode
+ * in question.
*
* Returns: errno
*/
-int gfs2_truncatei(struct gfs2_inode *ip, u64 size)
+int gfs2_setattr_size(struct inode *inode, u64 newsize)
{
- int error;
+ int ret;
+ u64 oldsize;
- if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), S_ISREG(ip->i_inode.i_mode)))
- return -EINVAL;
+ BUG_ON(!S_ISREG(inode->i_mode));
- if (size > ip->i_disksize)
- error = do_grow(ip, size);
- else if (size < ip->i_disksize)
- error = do_shrink(ip, size);
- else
- /* update time stamps */
- error = do_touch(ip, size);
+ ret = inode_newsize_ok(inode, newsize);
+ if (ret)
+ return ret;
- return error;
+ oldsize = inode->i_size;
+ if (newsize >= oldsize)
+ return do_grow(inode, newsize);
+
+ return do_shrink(inode, oldsize, newsize);
}
int gfs2_truncatei_resume(struct gfs2_inode *ip)