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Diffstat (limited to 'fs/ext4/indirect.c')
-rw-r--r--fs/ext4/indirect.c259
1 files changed, 251 insertions, 8 deletions
diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c
index 20862f96e8ae..c541ab8b64dd 100644
--- a/fs/ext4/indirect.c
+++ b/fs/ext4/indirect.c
@@ -146,6 +146,7 @@ static Indirect *ext4_get_branch(struct inode *inode, int depth,
struct super_block *sb = inode->i_sb;
Indirect *p = chain;
struct buffer_head *bh;
+ int ret = -EIO;
*err = 0;
/* i_data is not going away, no lock needed */
@@ -154,8 +155,10 @@ static Indirect *ext4_get_branch(struct inode *inode, int depth,
goto no_block;
while (--depth) {
bh = sb_getblk(sb, le32_to_cpu(p->key));
- if (unlikely(!bh))
+ if (unlikely(!bh)) {
+ ret = -ENOMEM;
goto failure;
+ }
if (!bh_uptodate_or_lock(bh)) {
if (bh_submit_read(bh) < 0) {
@@ -177,7 +180,7 @@ static Indirect *ext4_get_branch(struct inode *inode, int depth,
return NULL;
failure:
- *err = -EIO;
+ *err = ret;
no_block:
return p;
}
@@ -355,9 +358,8 @@ static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
* for the first direct block
*/
new_blocks[index] = current_block;
- printk(KERN_INFO "%s returned more blocks than "
+ WARN(1, KERN_INFO "%s returned more blocks than "
"requested\n", __func__);
- WARN_ON(1);
break;
}
}
@@ -471,7 +473,7 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
*/
bh = sb_getblk(inode->i_sb, new_blocks[n-1]);
if (unlikely(!bh)) {
- err = -EIO;
+ err = -ENOMEM;
goto failed;
}
@@ -789,7 +791,7 @@ ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
if (final_size > inode->i_size) {
/* Credits for sb + inode write */
- handle = ext4_journal_start(inode, 2);
+ handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
goto out;
@@ -849,7 +851,7 @@ locked:
int err;
/* Credits for sb + inode write */
- handle = ext4_journal_start(inode, 2);
+ handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
if (IS_ERR(handle)) {
/* This is really bad luck. We've written the data
* but cannot extend i_size. Bail out and pretend
@@ -948,7 +950,8 @@ static handle_t *start_transaction(struct inode *inode)
{
handle_t *result;
- result = ext4_journal_start(inode, ext4_blocks_for_truncate(inode));
+ result = ext4_journal_start(inode, EXT4_HT_TRUNCATE,
+ ext4_blocks_for_truncate(inode));
if (!IS_ERR(result))
return result;
@@ -1515,3 +1518,243 @@ out_stop:
trace_ext4_truncate_exit(inode);
}
+static int free_hole_blocks(handle_t *handle, struct inode *inode,
+ struct buffer_head *parent_bh, __le32 *i_data,
+ int level, ext4_lblk_t first,
+ ext4_lblk_t count, int max)
+{
+ struct buffer_head *bh = NULL;
+ int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb);
+ int ret = 0;
+ int i, inc;
+ ext4_lblk_t offset;
+ __le32 blk;
+
+ inc = 1 << ((EXT4_BLOCK_SIZE_BITS(inode->i_sb) - 2) * level);
+ for (i = 0, offset = 0; i < max; i++, i_data++, offset += inc) {
+ if (offset >= count + first)
+ break;
+ if (*i_data == 0 || (offset + inc) <= first)
+ continue;
+ blk = *i_data;
+ if (level > 0) {
+ ext4_lblk_t first2;
+ bh = sb_bread(inode->i_sb, blk);
+ if (!bh) {
+ EXT4_ERROR_INODE_BLOCK(inode, blk,
+ "Read failure");
+ return -EIO;
+ }
+ first2 = (first > offset) ? first - offset : 0;
+ ret = free_hole_blocks(handle, inode, bh,
+ (__le32 *)bh->b_data, level - 1,
+ first2, count - offset,
+ inode->i_sb->s_blocksize >> 2);
+ if (ret) {
+ brelse(bh);
+ goto err;
+ }
+ }
+ if (level == 0 ||
+ (bh && all_zeroes((__le32 *)bh->b_data,
+ (__le32 *)bh->b_data + addr_per_block))) {
+ ext4_free_data(handle, inode, parent_bh, &blk, &blk+1);
+ *i_data = 0;
+ }
+ brelse(bh);
+ bh = NULL;
+ }
+
+err:
+ return ret;
+}
+
+static int ext4_free_hole_blocks(handle_t *handle, struct inode *inode,
+ ext4_lblk_t first, ext4_lblk_t stop)
+{
+ int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb);
+ int level, ret = 0;
+ int num = EXT4_NDIR_BLOCKS;
+ ext4_lblk_t count, max = EXT4_NDIR_BLOCKS;
+ __le32 *i_data = EXT4_I(inode)->i_data;
+
+ count = stop - first;
+ for (level = 0; level < 4; level++, max *= addr_per_block) {
+ if (first < max) {
+ ret = free_hole_blocks(handle, inode, NULL, i_data,
+ level, first, count, num);
+ if (ret)
+ goto err;
+ if (count > max - first)
+ count -= max - first;
+ else
+ break;
+ first = 0;
+ } else {
+ first -= max;
+ }
+ i_data += num;
+ if (level == 0) {
+ num = 1;
+ max = 1;
+ }
+ }
+
+err:
+ return ret;
+}
+
+int ext4_ind_punch_hole(struct file *file, loff_t offset, loff_t length)
+{
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct super_block *sb = inode->i_sb;
+ ext4_lblk_t first_block, stop_block;
+ struct address_space *mapping = inode->i_mapping;
+ handle_t *handle = NULL;
+ loff_t first_page, last_page, page_len;
+ loff_t first_page_offset, last_page_offset;
+ int err = 0;
+
+ /*
+ * Write out all dirty pages to avoid race conditions
+ * Then release them.
+ */
+ if (mapping->nrpages && mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
+ err = filemap_write_and_wait_range(mapping,
+ offset, offset + length - 1);
+ if (err)
+ return err;
+ }
+
+ mutex_lock(&inode->i_mutex);
+ /* It's not possible punch hole on append only file */
+ if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) {
+ err = -EPERM;
+ goto out_mutex;
+ }
+ if (IS_SWAPFILE(inode)) {
+ err = -ETXTBSY;
+ goto out_mutex;
+ }
+
+ /* No need to punch hole beyond i_size */
+ if (offset >= inode->i_size)
+ goto out_mutex;
+
+ /*
+ * If the hole extents beyond i_size, set the hole
+ * to end after the page that contains i_size
+ */
+ if (offset + length > inode->i_size) {
+ length = inode->i_size +
+ PAGE_CACHE_SIZE - (inode->i_size & (PAGE_CACHE_SIZE - 1)) -
+ offset;
+ }
+
+ first_page = (offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+ last_page = (offset + length) >> PAGE_CACHE_SHIFT;
+
+ first_page_offset = first_page << PAGE_CACHE_SHIFT;
+ last_page_offset = last_page << PAGE_CACHE_SHIFT;
+
+ /* Now release the pages */
+ if (last_page_offset > first_page_offset) {
+ truncate_pagecache_range(inode, first_page_offset,
+ last_page_offset - 1);
+ }
+
+ /* Wait all existing dio works, newcomers will block on i_mutex */
+ inode_dio_wait(inode);
+
+ handle = start_transaction(inode);
+ if (IS_ERR(handle))
+ goto out_mutex;
+
+ /*
+ * Now we need to zero out the non-page-aligned data in the
+ * pages at the start and tail of the hole, and unmap the buffer
+ * heads for the block aligned regions of the page that were
+ * completely zerod.
+ */
+ if (first_page > last_page) {
+ /*
+ * If the file space being truncated is contained within a page
+ * just zero out and unmap the middle of that page
+ */
+ err = ext4_discard_partial_page_buffers(handle,
+ mapping, offset, length, 0);
+ if (err)
+ goto out;
+ } else {
+ /*
+ * Zero out and unmap the paritial page that contains
+ * the start of the hole
+ */
+ page_len = first_page_offset - offset;
+ if (page_len > 0) {
+ err = ext4_discard_partial_page_buffers(handle, mapping,
+ offset, page_len, 0);
+ if (err)
+ goto out;
+ }
+
+ /*
+ * Zero out and unmap the partial page that contains
+ * the end of the hole
+ */
+ page_len = offset + length - last_page_offset;
+ if (page_len > 0) {
+ err = ext4_discard_partial_page_buffers(handle, mapping,
+ last_page_offset, page_len, 0);
+ if (err)
+ goto out;
+ }
+ }
+
+ /*
+ * If i_size contained in the last page, we need to
+ * unmap and zero the paritial page after i_size
+ */
+ if (inode->i_size >> PAGE_CACHE_SHIFT == last_page &&
+ inode->i_size % PAGE_CACHE_SIZE != 0) {
+ page_len = PAGE_CACHE_SIZE -
+ (inode->i_size & (PAGE_CACHE_SIZE - 1));
+ if (page_len > 0) {
+ err = ext4_discard_partial_page_buffers(handle,
+ mapping, inode->i_size, page_len, 0);
+ if (err)
+ goto out;
+ }
+ }
+
+ first_block = (offset + sb->s_blocksize - 1) >>
+ EXT4_BLOCK_SIZE_BITS(sb);
+ stop_block = (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb);
+
+ if (first_block >= stop_block)
+ goto out;
+
+ down_write(&EXT4_I(inode)->i_data_sem);
+ ext4_discard_preallocations(inode);
+
+ err = ext4_es_remove_extent(inode, first_block,
+ stop_block - first_block);
+ err = ext4_free_hole_blocks(handle, inode, first_block, stop_block);
+
+ ext4_discard_preallocations(inode);
+
+ if (IS_SYNC(inode))
+ ext4_handle_sync(handle);
+
+ up_write(&EXT4_I(inode)->i_data_sem);
+
+out:
+ inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
+ ext4_mark_inode_dirty(handle, inode);
+ ext4_journal_stop(handle);
+
+out_mutex:
+ mutex_unlock(&inode->i_mutex);
+
+ return err;
+}