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@@ -723,7 +723,7 @@ err:
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* insert new index [@logical;@ptr] into the block at @curp;
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* check where to insert: before @curp or after @curp
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*/
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-static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
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+int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
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struct ext4_ext_path *curp,
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int logical, ext4_fsblk_t ptr)
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{
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@@ -1586,7 +1586,7 @@ out:
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*/
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int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
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struct ext4_ext_path *path,
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- struct ext4_extent *newext)
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+ struct ext4_extent *newext, int flag)
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{
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struct ext4_extent_header *eh;
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struct ext4_extent *ex, *fex;
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@@ -1602,7 +1602,8 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
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BUG_ON(path[depth].p_hdr == NULL);
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/* try to insert block into found extent and return */
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- if (ex && ext4_can_extents_be_merged(inode, ex, newext)) {
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+ if (ex && (flag != EXT4_GET_BLOCKS_DIO_CREATE_EXT)
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+ && ext4_can_extents_be_merged(inode, ex, newext)) {
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ext_debug("append [%d]%d block to %d:[%d]%d (from %llu)\n",
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ext4_ext_is_uninitialized(newext),
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ext4_ext_get_actual_len(newext),
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@@ -1722,7 +1723,8 @@ has_space:
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merge:
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/* try to merge extents to the right */
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- ext4_ext_try_to_merge(inode, path, nearex);
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+ if (flag != EXT4_GET_BLOCKS_DIO_CREATE_EXT)
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+ ext4_ext_try_to_merge(inode, path, nearex);
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/* try to merge extents to the left */
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@@ -2490,7 +2492,6 @@ static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
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}
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#define EXT4_EXT_ZERO_LEN 7
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-
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/*
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* This function is called by ext4_ext_get_blocks() if someone tries to write
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* to an uninitialized extent. It may result in splitting the uninitialized
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@@ -2583,7 +2584,8 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
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ex3->ee_block = cpu_to_le32(iblock);
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ext4_ext_store_pblock(ex3, newblock);
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ex3->ee_len = cpu_to_le16(allocated);
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- err = ext4_ext_insert_extent(handle, inode, path, ex3);
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+ err = ext4_ext_insert_extent(handle, inode, path,
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+ ex3, 0);
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if (err == -ENOSPC) {
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err = ext4_ext_zeroout(inode, &orig_ex);
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if (err)
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@@ -2639,7 +2641,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
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ext4_ext_store_pblock(ex3, newblock + max_blocks);
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ex3->ee_len = cpu_to_le16(allocated - max_blocks);
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ext4_ext_mark_uninitialized(ex3);
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- err = ext4_ext_insert_extent(handle, inode, path, ex3);
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+ err = ext4_ext_insert_extent(handle, inode, path, ex3, 0);
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if (err == -ENOSPC) {
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err = ext4_ext_zeroout(inode, &orig_ex);
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if (err)
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@@ -2757,7 +2759,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
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err = ext4_ext_dirty(handle, inode, path + depth);
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goto out;
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insert:
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- err = ext4_ext_insert_extent(handle, inode, path, &newex);
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+ err = ext4_ext_insert_extent(handle, inode, path, &newex, 0);
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if (err == -ENOSPC) {
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err = ext4_ext_zeroout(inode, &orig_ex);
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if (err)
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@@ -2784,6 +2786,320 @@ fix_extent_len:
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return err;
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}
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+/*
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+ * This function is called by ext4_ext_get_blocks() from
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+ * ext4_get_blocks_dio_write() when DIO to write
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+ * to an uninitialized extent.
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+ *
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+ * Writing to an uninitized extent may result in splitting the uninitialized
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+ * extent into multiple /intialized unintialized extents (up to three)
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+ * There are three possibilities:
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+ * a> There is no split required: Entire extent should be uninitialized
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+ * b> Splits in two extents: Write is happening at either end of the extent
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+ * c> Splits in three extents: Somone is writing in middle of the extent
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+ *
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+ * One of more index blocks maybe needed if the extent tree grow after
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+ * the unintialized extent split. To prevent ENOSPC occur at the IO
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+ * complete, we need to split the uninitialized extent before DIO submit
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+ * the IO. The uninitilized extent called at this time will be split
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+ * into three uninitialized extent(at most). After IO complete, the part
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+ * being filled will be convert to initialized by the end_io callback function
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+ * via ext4_convert_unwritten_extents().
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+ */
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+static int ext4_split_unwritten_extents(handle_t *handle,
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+ struct inode *inode,
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+ struct ext4_ext_path *path,
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+ ext4_lblk_t iblock,
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+ unsigned int max_blocks,
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+ int flags)
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+{
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+ struct ext4_extent *ex, newex, orig_ex;
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+ struct ext4_extent *ex1 = NULL;
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+ struct ext4_extent *ex2 = NULL;
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+ struct ext4_extent *ex3 = NULL;
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+ struct ext4_extent_header *eh;
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+ ext4_lblk_t ee_block;
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+ unsigned int allocated, ee_len, depth;
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+ ext4_fsblk_t newblock;
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+ int err = 0;
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+ int ret = 0;
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+
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+ ext_debug("ext4_split_unwritten_extents: inode %lu,"
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+ "iblock %llu, max_blocks %u\n", inode->i_ino,
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+ (unsigned long long)iblock, max_blocks);
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+ depth = ext_depth(inode);
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+ eh = path[depth].p_hdr;
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+ ex = path[depth].p_ext;
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+ ee_block = le32_to_cpu(ex->ee_block);
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+ ee_len = ext4_ext_get_actual_len(ex);
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+ allocated = ee_len - (iblock - ee_block);
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+ newblock = iblock - ee_block + ext_pblock(ex);
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+ ex2 = ex;
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+ orig_ex.ee_block = ex->ee_block;
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+ orig_ex.ee_len = cpu_to_le16(ee_len);
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+ ext4_ext_store_pblock(&orig_ex, ext_pblock(ex));
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+
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+ /*
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+ * if the entire unintialized extent length less than
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+ * the size of extent to write, there is no need to split
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+ * uninitialized extent
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+ */
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+ if (allocated <= max_blocks)
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+ return ret;
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+
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+ err = ext4_ext_get_access(handle, inode, path + depth);
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+ if (err)
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+ goto out;
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+ /* ex1: ee_block to iblock - 1 : uninitialized */
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+ if (iblock > ee_block) {
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+ ex1 = ex;
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+ ex1->ee_len = cpu_to_le16(iblock - ee_block);
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+ ext4_ext_mark_uninitialized(ex1);
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+ ex2 = &newex;
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+ }
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+ /*
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+ * for sanity, update the length of the ex2 extent before
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+ * we insert ex3, if ex1 is NULL. This is to avoid temporary
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+ * overlap of blocks.
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+ */
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+ if (!ex1 && allocated > max_blocks)
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+ ex2->ee_len = cpu_to_le16(max_blocks);
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+ /* ex3: to ee_block + ee_len : uninitialised */
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+ if (allocated > max_blocks) {
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+ unsigned int newdepth;
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+ ex3 = &newex;
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+ ex3->ee_block = cpu_to_le32(iblock + max_blocks);
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+ ext4_ext_store_pblock(ex3, newblock + max_blocks);
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+ ex3->ee_len = cpu_to_le16(allocated - max_blocks);
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+ ext4_ext_mark_uninitialized(ex3);
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+ err = ext4_ext_insert_extent(handle, inode, path, ex3, flags);
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+ if (err == -ENOSPC) {
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+ err = ext4_ext_zeroout(inode, &orig_ex);
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+ if (err)
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+ goto fix_extent_len;
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+ /* update the extent length and mark as initialized */
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+ ex->ee_block = orig_ex.ee_block;
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+ ex->ee_len = orig_ex.ee_len;
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+ ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
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+ ext4_ext_dirty(handle, inode, path + depth);
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+ /* zeroed the full extent */
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+ /* blocks available from iblock */
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+ return allocated;
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+
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+ } else if (err)
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+ goto fix_extent_len;
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+ /*
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+ * The depth, and hence eh & ex might change
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+ * as part of the insert above.
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+ */
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+ newdepth = ext_depth(inode);
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+ /*
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+ * update the extent length after successful insert of the
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+ * split extent
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+ */
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+ orig_ex.ee_len = cpu_to_le16(ee_len -
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+ ext4_ext_get_actual_len(ex3));
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+ depth = newdepth;
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+ ext4_ext_drop_refs(path);
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+ path = ext4_ext_find_extent(inode, iblock, path);
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+ if (IS_ERR(path)) {
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+ err = PTR_ERR(path);
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+ goto out;
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+ }
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+ eh = path[depth].p_hdr;
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+ ex = path[depth].p_ext;
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+ if (ex2 != &newex)
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+ ex2 = ex;
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+
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+ err = ext4_ext_get_access(handle, inode, path + depth);
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+ if (err)
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+ goto out;
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+
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+ allocated = max_blocks;
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+ }
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+ /*
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+ * If there was a change of depth as part of the
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+ * insertion of ex3 above, we need to update the length
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+ * of the ex1 extent again here
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+ */
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+ if (ex1 && ex1 != ex) {
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+ ex1 = ex;
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+ ex1->ee_len = cpu_to_le16(iblock - ee_block);
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+ ext4_ext_mark_uninitialized(ex1);
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+ ex2 = &newex;
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+ }
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+ /*
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+ * ex2: iblock to iblock + maxblocks-1 : to be direct IO written,
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+ * uninitialised still.
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+ */
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+ ex2->ee_block = cpu_to_le32(iblock);
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+ ext4_ext_store_pblock(ex2, newblock);
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+ ex2->ee_len = cpu_to_le16(allocated);
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+ ext4_ext_mark_uninitialized(ex2);
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+ if (ex2 != ex)
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+ goto insert;
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+ /* Mark modified extent as dirty */
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+ err = ext4_ext_dirty(handle, inode, path + depth);
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+ ext_debug("out here\n");
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+ goto out;
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+insert:
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+ err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
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+ if (err == -ENOSPC) {
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+ err = ext4_ext_zeroout(inode, &orig_ex);
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+ if (err)
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+ goto fix_extent_len;
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+ /* update the extent length and mark as initialized */
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+ ex->ee_block = orig_ex.ee_block;
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+ ex->ee_len = orig_ex.ee_len;
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+ ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
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+ ext4_ext_dirty(handle, inode, path + depth);
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+ /* zero out the first half */
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+ return allocated;
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+ } else if (err)
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+ goto fix_extent_len;
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+out:
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+ ext4_ext_show_leaf(inode, path);
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+ return err ? err : allocated;
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+
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+fix_extent_len:
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+ ex->ee_block = orig_ex.ee_block;
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+ ex->ee_len = orig_ex.ee_len;
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+ ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
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+ ext4_ext_mark_uninitialized(ex);
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+ ext4_ext_dirty(handle, inode, path + depth);
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+ return err;
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+}
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+static int ext4_convert_unwritten_extents_dio(handle_t *handle,
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+ struct inode *inode,
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+ struct ext4_ext_path *path)
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+{
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+ struct ext4_extent *ex;
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+ struct ext4_extent_header *eh;
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+ int depth;
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+ int err = 0;
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+ int ret = 0;
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+
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+ depth = ext_depth(inode);
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+ eh = path[depth].p_hdr;
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+ ex = path[depth].p_ext;
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+
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+ err = ext4_ext_get_access(handle, inode, path + depth);
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+ if (err)
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+ goto out;
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+ /* first mark the extent as initialized */
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+ ext4_ext_mark_initialized(ex);
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+
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+ /*
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+ * We have to see if it can be merged with the extent
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+ * on the left.
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+ */
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+ if (ex > EXT_FIRST_EXTENT(eh)) {
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+ /*
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+ * To merge left, pass "ex - 1" to try_to_merge(),
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+ * since it merges towards right _only_.
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+ */
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+ ret = ext4_ext_try_to_merge(inode, path, ex - 1);
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+ if (ret) {
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+ err = ext4_ext_correct_indexes(handle, inode, path);
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+ if (err)
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+ goto out;
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+ depth = ext_depth(inode);
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+ ex--;
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+ }
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+ }
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|
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+ /*
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+ * Try to Merge towards right.
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+ */
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+ ret = ext4_ext_try_to_merge(inode, path, ex);
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+ if (ret) {
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+ err = ext4_ext_correct_indexes(handle, inode, path);
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+ if (err)
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+ goto out;
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+ depth = ext_depth(inode);
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+ }
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+ /* Mark modified extent as dirty */
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+ err = ext4_ext_dirty(handle, inode, path + depth);
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+out:
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+ ext4_ext_show_leaf(inode, path);
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+ return err;
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+}
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+
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+static int
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+ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
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|
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+ ext4_lblk_t iblock, unsigned int max_blocks,
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+ struct ext4_ext_path *path, int flags,
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+ unsigned int allocated, struct buffer_head *bh_result,
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+ ext4_fsblk_t newblock)
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|
|
+{
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|
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+ int ret = 0;
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+ int err = 0;
|
|
|
+
|
|
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+ ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical"
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|
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+ "block %llu, max_blocks %u, flags %d, allocated %u",
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|
|
+ inode->i_ino, (unsigned long long)iblock, max_blocks,
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+ flags, allocated);
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|
+ ext4_ext_show_leaf(inode, path);
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+
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+ /* DIO get_block() before submit the IO, split the extent */
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+ if (flags == EXT4_GET_BLOCKS_DIO_CREATE_EXT) {
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|
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+ ret = ext4_split_unwritten_extents(handle,
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+ inode, path, iblock,
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+ max_blocks, flags);
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+ goto out;
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+ }
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|
|
+ /* DIO end_io complete, convert the filled extent to written */
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|
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+ if (flags == EXT4_GET_BLOCKS_DIO_CONVERT_EXT) {
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+ ret = ext4_convert_unwritten_extents_dio(handle, inode,
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+ path);
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+ goto out2;
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+ }
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|
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+ /* buffered IO case */
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+ /*
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+ * repeat fallocate creation request
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+ * we already have an unwritten extent
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+ */
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+ if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)
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+ goto map_out;
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+
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+ /* buffered READ or buffered write_begin() lookup */
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+ if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
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|
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+ /*
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|
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+ * We have blocks reserved already. We
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+ * return allocated blocks so that delalloc
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+ * won't do block reservation for us. But
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|
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+ * the buffer head will be unmapped so that
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|
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+ * a read from the block returns 0s.
|
|
|
+ */
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+ set_buffer_unwritten(bh_result);
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+ goto out1;
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+ }
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|
|
+
|
|
|
+ /* buffered write, writepage time, convert*/
|
|
|
+ ret = ext4_ext_convert_to_initialized(handle, inode,
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|
|
+ path, iblock,
|
|
|
+ max_blocks);
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|
|
+out:
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+ if (ret <= 0) {
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|
+ err = ret;
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+ goto out2;
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|
|
+ } else
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|
+ allocated = ret;
|
|
|
+ set_buffer_new(bh_result);
|
|
|
+map_out:
|
|
|
+ set_buffer_mapped(bh_result);
|
|
|
+out1:
|
|
|
+ if (allocated > max_blocks)
|
|
|
+ allocated = max_blocks;
|
|
|
+ ext4_ext_show_leaf(inode, path);
|
|
|
+ bh_result->b_bdev = inode->i_sb->s_bdev;
|
|
|
+ bh_result->b_blocknr = newblock;
|
|
|
+out2:
|
|
|
+ if (path) {
|
|
|
+ ext4_ext_drop_refs(path);
|
|
|
+ kfree(path);
|
|
|
+ }
|
|
|
+ return err ? err : allocated;
|
|
|
+}
|
|
|
/*
|
|
|
* Block allocation/map/preallocation routine for extents based files
|
|
|
*
|
|
@@ -2889,33 +3205,10 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
|
|
|
EXT4_EXT_CACHE_EXTENT);
|
|
|
goto out;
|
|
|
}
|
|
|
- if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)
|
|
|
- goto out;
|
|
|
- if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
|
|
|
- if (allocated > max_blocks)
|
|
|
- allocated = max_blocks;
|
|
|
- /*
|
|
|
- * We have blocks reserved already. We
|
|
|
- * return allocated blocks so that delalloc
|
|
|
- * won't do block reservation for us. But
|
|
|
- * the buffer head will be unmapped so that
|
|
|
- * a read from the block returns 0s.
|
|
|
- */
|
|
|
- set_buffer_unwritten(bh_result);
|
|
|
- bh_result->b_bdev = inode->i_sb->s_bdev;
|
|
|
- bh_result->b_blocknr = newblock;
|
|
|
- goto out2;
|
|
|
- }
|
|
|
-
|
|
|
- ret = ext4_ext_convert_to_initialized(handle, inode,
|
|
|
- path, iblock,
|
|
|
- max_blocks);
|
|
|
- if (ret <= 0) {
|
|
|
- err = ret;
|
|
|
- goto out2;
|
|
|
- } else
|
|
|
- allocated = ret;
|
|
|
- goto outnew;
|
|
|
+ ret = ext4_ext_handle_uninitialized_extents(handle,
|
|
|
+ inode, iblock, max_blocks, path,
|
|
|
+ flags, allocated, bh_result, newblock);
|
|
|
+ return ret;
|
|
|
}
|
|
|
}
|
|
|
|
|
@@ -2988,7 +3281,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
|
|
|
newex.ee_len = cpu_to_le16(ar.len);
|
|
|
if (flags & EXT4_GET_BLOCKS_UNINIT_EXT) /* Mark uninitialized */
|
|
|
ext4_ext_mark_uninitialized(&newex);
|
|
|
- err = ext4_ext_insert_extent(handle, inode, path, &newex);
|
|
|
+ err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
|
|
|
if (err) {
|
|
|
/* free data blocks we just allocated */
|
|
|
/* not a good idea to call discard here directly,
|
|
@@ -3002,7 +3295,6 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
|
|
|
/* previous routine could use block we allocated */
|
|
|
newblock = ext_pblock(&newex);
|
|
|
allocated = ext4_ext_get_actual_len(&newex);
|
|
|
-outnew:
|
|
|
set_buffer_new(bh_result);
|
|
|
|
|
|
/* Cache only when it is _not_ an uninitialized extent */
|
|
@@ -3200,6 +3492,63 @@ retry:
|
|
|
return ret > 0 ? ret2 : ret;
|
|
|
}
|
|
|
|
|
|
+/*
|
|
|
+ * This function convert a range of blocks to written extents
|
|
|
+ * The caller of this function will pass the start offset and the size.
|
|
|
+ * all unwritten extents within this range will be converted to
|
|
|
+ * written extents.
|
|
|
+ *
|
|
|
+ * This function is called from the direct IO end io call back
|
|
|
+ * function, to convert the fallocated extents after IO is completed.
|
|
|
+ */
|
|
|
+int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
|
|
|
+ loff_t len)
|
|
|
+{
|
|
|
+ handle_t *handle;
|
|
|
+ ext4_lblk_t block;
|
|
|
+ unsigned int max_blocks;
|
|
|
+ int ret = 0;
|
|
|
+ int ret2 = 0;
|
|
|
+ struct buffer_head map_bh;
|
|
|
+ unsigned int credits, blkbits = inode->i_blkbits;
|
|
|
+
|
|
|
+ block = offset >> blkbits;
|
|
|
+ /*
|
|
|
+ * We can't just convert len to max_blocks because
|
|
|
+ * If blocksize = 4096 offset = 3072 and len = 2048
|
|
|
+ */
|
|
|
+ max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
|
|
|
+ - block;
|
|
|
+ /*
|
|
|
+ * credits to insert 1 extent into extent tree
|
|
|
+ */
|
|
|
+ credits = ext4_chunk_trans_blocks(inode, max_blocks);
|
|
|
+ while (ret >= 0 && ret < max_blocks) {
|
|
|
+ block = block + ret;
|
|
|
+ max_blocks = max_blocks - ret;
|
|
|
+ handle = ext4_journal_start(inode, credits);
|
|
|
+ if (IS_ERR(handle)) {
|
|
|
+ ret = PTR_ERR(handle);
|
|
|
+ break;
|
|
|
+ }
|
|
|
+ map_bh.b_state = 0;
|
|
|
+ ret = ext4_get_blocks(handle, inode, block,
|
|
|
+ max_blocks, &map_bh,
|
|
|
+ EXT4_GET_BLOCKS_DIO_CONVERT_EXT);
|
|
|
+ if (ret <= 0) {
|
|
|
+ WARN_ON(ret <= 0);
|
|
|
+ printk(KERN_ERR "%s: ext4_ext_get_blocks "
|
|
|
+ "returned error inode#%lu, block=%u, "
|
|
|
+ "max_blocks=%u", __func__,
|
|
|
+ inode->i_ino, block, max_blocks);
|
|
|
+ }
|
|
|
+ ext4_mark_inode_dirty(handle, inode);
|
|
|
+ ret2 = ext4_journal_stop(handle);
|
|
|
+ if (ret <= 0 || ret2 )
|
|
|
+ break;
|
|
|
+ }
|
|
|
+ return ret > 0 ? ret2 : ret;
|
|
|
+}
|
|
|
/*
|
|
|
* Callback function called for each extent to gather FIEMAP information.
|
|
|
*/
|