#include "ext4_jbd2.h"
#include "ext4_extents.h"
+#include <trace/events/ext4.h>
-/*
- * ext_pblock:
- * combine low and high parts of physical block number into ext4_fsblk_t
- */
-ext4_fsblk_t ext_pblock(struct ext4_extent *ex)
-{
- ext4_fsblk_t block;
-
- block = le32_to_cpu(ex->ee_start_lo);
- block |= ((ext4_fsblk_t) le16_to_cpu(ex->ee_start_hi) << 31) << 1;
- return block;
-}
-
-/*
- * idx_pblock:
- * combine low and high parts of a leaf physical block number into ext4_fsblk_t
- */
-ext4_fsblk_t idx_pblock(struct ext4_extent_idx *ix)
-{
- ext4_fsblk_t block;
-
- block = le32_to_cpu(ix->ei_leaf_lo);
- block |= ((ext4_fsblk_t) le16_to_cpu(ix->ei_leaf_hi) << 31) << 1;
- return block;
-}
-
-/*
- * ext4_ext_store_pblock:
- * stores a large physical block number into an extent struct,
- * breaking it into parts
- */
-void ext4_ext_store_pblock(struct ext4_extent *ex, ext4_fsblk_t pb)
-{
- ex->ee_start_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff));
- ex->ee_start_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
-}
-
-/*
- * ext4_idx_store_pblock:
- * stores a large physical block number into an index struct,
- * breaking it into parts
- */
-static void ext4_idx_store_pblock(struct ext4_extent_idx *ix, ext4_fsblk_t pb)
-{
- ix->ei_leaf_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff));
- ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
-}
+static int ext4_split_extent(handle_t *handle,
+ struct inode *inode,
+ struct ext4_ext_path *path,
+ struct ext4_map_blocks *map,
+ int split_flag,
+ int flags);
static int ext4_ext_truncate_extend_restart(handle_t *handle,
struct inode *inode,
if (err <= 0)
return err;
err = ext4_truncate_restart_trans(handle, inode, needed);
- /*
- * We have dropped i_data_sem so someone might have cached again
- * an extent we are going to truncate.
- */
- ext4_ext_invalidate_cache(inode);
+ if (err == 0)
+ err = -EAGAIN;
return err;
}
struct ext4_ext_path *path,
ext4_lblk_t block)
{
- struct ext4_inode_info *ei = EXT4_I(inode);
- ext4_fsblk_t bg_start;
- ext4_fsblk_t last_block;
- ext4_grpblk_t colour;
- ext4_group_t block_group;
- int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb));
int depth;
if (path) {
struct ext4_extent *ex;
depth = path->p_depth;
- /* try to predict block placement */
+ /*
+ * Try to predict block placement assuming that we are
+ * filling in a file which will eventually be
+ * non-sparse --- i.e., in the case of libbfd writing
+ * an ELF object sections out-of-order but in a way
+ * the eventually results in a contiguous object or
+ * executable file, or some database extending a table
+ * space file. However, this is actually somewhat
+ * non-ideal if we are writing a sparse file such as
+ * qemu or KVM writing a raw image file that is going
+ * to stay fairly sparse, since it will end up
+ * fragmenting the file system's free space. Maybe we
+ * should have some hueristics or some way to allow
+ * userspace to pass a hint to file system,
+ * especially if the latter case turns out to be
+ * common.
+ */
ex = path[depth].p_ext;
- if (ex)
- return ext_pblock(ex)+(block-le32_to_cpu(ex->ee_block));
+ if (ex) {
+ ext4_fsblk_t ext_pblk = ext4_ext_pblock(ex);
+ ext4_lblk_t ext_block = le32_to_cpu(ex->ee_block);
+
+ if (block > ext_block)
+ return ext_pblk + (block - ext_block);
+ else
+ return ext_pblk - (ext_block - block);
+ }
/* it looks like index is empty;
* try to find starting block from index itself */
}
/* OK. use inode's group */
- block_group = ei->i_block_group;
- if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) {
- /*
- * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME
- * block groups per flexgroup, reserve the first block
- * group for directories and special files. Regular
- * files will start at the second block group. This
- * tends to speed up directory access and improves
- * fsck times.
- */
- block_group &= ~(flex_size-1);
- if (S_ISREG(inode->i_mode))
- block_group++;
- }
- bg_start = ext4_group_first_block_no(inode->i_sb, block_group);
- last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;
-
- /*
- * If we are doing delayed allocation, we don't need take
- * colour into account.
- */
- if (test_opt(inode->i_sb, DELALLOC))
- return bg_start;
-
- if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block)
- colour = (current->pid % 16) *
- (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
- else
- colour = (current->pid % 16) * ((last_block - bg_start) / 16);
- return bg_start + colour + block;
+ return ext4_inode_to_goal_block(inode);
}
/*
static ext4_fsblk_t
ext4_ext_new_meta_block(handle_t *handle, struct inode *inode,
struct ext4_ext_path *path,
- struct ext4_extent *ex, int *err)
+ struct ext4_extent *ex, int *err, unsigned int flags)
{
ext4_fsblk_t goal, newblock;
goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
- newblock = ext4_new_meta_blocks(handle, inode, goal, NULL, err);
+ newblock = ext4_new_meta_blocks(handle, inode, goal, flags,
+ NULL, err);
return newblock;
}
* to allocate @blocks
* Worse case is one block per extent
*/
-int ext4_ext_calc_metadata_amount(struct inode *inode, sector_t lblock)
+int ext4_ext_calc_metadata_amount(struct inode *inode, ext4_lblk_t lblock)
{
struct ext4_inode_info *ei = EXT4_I(inode);
int idxs, num = 0;
static int ext4_valid_extent(struct inode *inode, struct ext4_extent *ext)
{
- ext4_fsblk_t block = ext_pblock(ext);
+ ext4_fsblk_t block = ext4_ext_pblock(ext);
int len = ext4_ext_get_actual_len(ext);
return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len);
static int ext4_valid_extent_idx(struct inode *inode,
struct ext4_extent_idx *ext_idx)
{
- ext4_fsblk_t block = idx_pblock(ext_idx);
+ ext4_fsblk_t block = ext4_idx_pblock(ext_idx);
return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, 1);
}
return 1;
}
-static int __ext4_ext_check(const char *function, struct inode *inode,
- struct ext4_extent_header *eh,
- int depth)
+static int __ext4_ext_check(const char *function, unsigned int line,
+ struct inode *inode, struct ext4_extent_header *eh,
+ int depth)
{
const char *error_msg;
int max = 0;
return 0;
corrupted:
- ext4_error_inode(function, inode,
+ ext4_error_inode(inode, function, line, 0,
"bad header/extent: %s - magic %x, "
"entries %u, max %u(%u), depth %u(%u)",
error_msg, le16_to_cpu(eh->eh_magic),
}
#define ext4_ext_check(inode, eh, depth) \
- __ext4_ext_check(__func__, inode, eh, depth)
+ __ext4_ext_check(__func__, __LINE__, inode, eh, depth)
int ext4_ext_check_inode(struct inode *inode)
{
for (k = 0; k <= l; k++, path++) {
if (path->p_idx) {
ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block),
- idx_pblock(path->p_idx));
+ ext4_idx_pblock(path->p_idx));
} else if (path->p_ext) {
ext_debug(" %d:[%d]%d:%llu ",
le32_to_cpu(path->p_ext->ee_block),
ext4_ext_is_uninitialized(path->p_ext),
ext4_ext_get_actual_len(path->p_ext),
- ext_pblock(path->p_ext));
+ ext4_ext_pblock(path->p_ext));
} else
ext_debug(" []");
}
for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex->ee_block),
ext4_ext_is_uninitialized(ex),
- ext4_ext_get_actual_len(ex), ext_pblock(ex));
+ ext4_ext_get_actual_len(ex), ext4_ext_pblock(ex));
}
ext_debug("\n");
}
+
+static void ext4_ext_show_move(struct inode *inode, struct ext4_ext_path *path,
+ ext4_fsblk_t newblock, int level)
+{
+ int depth = ext_depth(inode);
+ struct ext4_extent *ex;
+
+ if (depth != level) {
+ struct ext4_extent_idx *idx;
+ idx = path[level].p_idx;
+ while (idx <= EXT_MAX_INDEX(path[level].p_hdr)) {
+ ext_debug("%d: move %d:%llu in new index %llu\n", level,
+ le32_to_cpu(idx->ei_block),
+ ext4_idx_pblock(idx),
+ newblock);
+ idx++;
+ }
+
+ return;
+ }
+
+ ex = path[depth].p_ext;
+ while (ex <= EXT_MAX_EXTENT(path[depth].p_hdr)) {
+ ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
+ le32_to_cpu(ex->ee_block),
+ ext4_ext_pblock(ex),
+ ext4_ext_is_uninitialized(ex),
+ ext4_ext_get_actual_len(ex),
+ newblock);
+ ex++;
+ }
+}
+
#else
#define ext4_ext_show_path(inode, path)
#define ext4_ext_show_leaf(inode, path)
+#define ext4_ext_show_move(inode, path, newblock, level)
#endif
void ext4_ext_drop_refs(struct ext4_ext_path *path)
path->p_idx = l - 1;
ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block),
- idx_pblock(path->p_idx));
+ ext4_idx_pblock(path->p_idx));
#ifdef CHECK_BINSEARCH
{
path->p_ext = l - 1;
ext_debug(" -> %d:%llu:[%d]%d ",
le32_to_cpu(path->p_ext->ee_block),
- ext_pblock(path->p_ext),
+ ext4_ext_pblock(path->p_ext),
ext4_ext_is_uninitialized(path->p_ext),
ext4_ext_get_actual_len(path->p_ext));
ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
ext4_ext_binsearch_idx(inode, path + ppos, block);
- path[ppos].p_block = idx_pblock(path[ppos].p_idx);
+ path[ppos].p_block = ext4_idx_pblock(path[ppos].p_idx);
path[ppos].p_depth = i;
path[ppos].p_ext = NULL;
if (unlikely(!bh))
goto err;
if (!bh_uptodate_or_lock(bh)) {
+ trace_ext4_ext_load_extent(inode, block,
+ path[ppos].p_block);
if (bh_submit_read(bh) < 0) {
put_bh(bh);
goto err;
ext4_ext_binsearch(inode, path + ppos, block);
/* if not an empty leaf */
if (path[ppos].p_ext)
- path[ppos].p_block = ext_pblock(path[ppos].p_ext);
+ path[ppos].p_block = ext4_ext_pblock(path[ppos].p_ext);
ext4_ext_show_path(inode, path);
* insert new index [@logical;@ptr] into the block at @curp;
* check where to insert: before @curp or after @curp
*/
-int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
- struct ext4_ext_path *curp,
- int logical, ext4_fsblk_t ptr)
+static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *curp,
+ int logical, ext4_fsblk_t ptr)
{
struct ext4_extent_idx *ix;
int len, err;
if (unlikely(le16_to_cpu(curp->p_hdr->eh_entries)
> le16_to_cpu(curp->p_hdr->eh_max))) {
EXT4_ERROR_INODE(inode,
- "logical %d == ei_block %d!",
- logical, le32_to_cpu(curp->p_idx->ei_block));
+ "eh_entries %d > eh_max %d!",
+ le16_to_cpu(curp->p_hdr->eh_entries),
+ le16_to_cpu(curp->p_hdr->eh_max));
return -EIO;
}
if (unlikely(ix > EXT_LAST_INDEX(curp->p_hdr))) {
* - initializes subtree
*/
static int ext4_ext_split(handle_t *handle, struct inode *inode,
- struct ext4_ext_path *path,
- struct ext4_extent *newext, int at)
+ unsigned int flags,
+ struct ext4_ext_path *path,
+ struct ext4_extent *newext, int at)
{
struct buffer_head *bh = NULL;
int depth = ext_depth(inode);
struct ext4_extent_header *neh;
struct ext4_extent_idx *fidx;
- struct ext4_extent *ex;
int i = at, k, m, a;
ext4_fsblk_t newblock, oldblock;
__le32 border;
ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
for (a = 0; a < depth - at; a++) {
newblock = ext4_ext_new_meta_block(handle, inode, path,
- newext, &err);
+ newext, &err, flags);
if (newblock == 0)
goto cleanup;
ablocks[a] = newblock;
neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
neh->eh_magic = EXT4_EXT_MAGIC;
neh->eh_depth = 0;
- ex = EXT_FIRST_EXTENT(neh);
/* move remainder of path[depth] to the new leaf */
if (unlikely(path[depth].p_hdr->eh_entries !=
goto cleanup;
}
/* start copy from next extent */
- /* TODO: we could do it by single memmove */
- m = 0;
- path[depth].p_ext++;
- while (path[depth].p_ext <=
- EXT_MAX_EXTENT(path[depth].p_hdr)) {
- ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
- le32_to_cpu(path[depth].p_ext->ee_block),
- ext_pblock(path[depth].p_ext),
- ext4_ext_is_uninitialized(path[depth].p_ext),
- ext4_ext_get_actual_len(path[depth].p_ext),
- newblock);
- /*memmove(ex++, path[depth].p_ext++,
- sizeof(struct ext4_extent));
- neh->eh_entries++;*/
- path[depth].p_ext++;
- m++;
- }
+ m = EXT_MAX_EXTENT(path[depth].p_hdr) - path[depth].p_ext++;
+ ext4_ext_show_move(inode, path, newblock, depth);
if (m) {
- memmove(ex, path[depth].p_ext-m, sizeof(struct ext4_extent)*m);
+ struct ext4_extent *ex;
+ ex = EXT_FIRST_EXTENT(neh);
+ memmove(ex, path[depth].p_ext, sizeof(struct ext4_extent) * m);
le16_add_cpu(&neh->eh_entries, m);
}
ext_debug("int.index at %d (block %llu): %u -> %llu\n",
i, newblock, le32_to_cpu(border), oldblock);
- /* copy indexes */
- m = 0;
- path[i].p_idx++;
- ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
- EXT_MAX_INDEX(path[i].p_hdr));
+ /* move remainder of path[i] to the new index block */
if (unlikely(EXT_MAX_INDEX(path[i].p_hdr) !=
EXT_LAST_INDEX(path[i].p_hdr))) {
EXT4_ERROR_INODE(inode,
err = -EIO;
goto cleanup;
}
- while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
- ext_debug("%d: move %d:%llu in new index %llu\n", i,
- le32_to_cpu(path[i].p_idx->ei_block),
- idx_pblock(path[i].p_idx),
- newblock);
- /*memmove(++fidx, path[i].p_idx++,
- sizeof(struct ext4_extent_idx));
- neh->eh_entries++;
- BUG_ON(neh->eh_entries > neh->eh_max);*/
- path[i].p_idx++;
- m++;
- }
+ /* start copy indexes */
+ m = EXT_MAX_INDEX(path[i].p_hdr) - path[i].p_idx++;
+ ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
+ EXT_MAX_INDEX(path[i].p_hdr));
+ ext4_ext_show_move(inode, path, newblock, i);
if (m) {
- memmove(++fidx, path[i].p_idx - m,
+ memmove(++fidx, path[i].p_idx,
sizeof(struct ext4_extent_idx) * m);
le16_add_cpu(&neh->eh_entries, m);
}
for (i = 0; i < depth; i++) {
if (!ablocks[i])
continue;
- ext4_free_blocks(handle, inode, 0, ablocks[i], 1,
+ ext4_free_blocks(handle, inode, NULL, ablocks[i], 1,
EXT4_FREE_BLOCKS_METADATA);
}
}
* just created block
*/
static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
- struct ext4_ext_path *path,
- struct ext4_extent *newext)
+ unsigned int flags,
+ struct ext4_ext_path *path,
+ struct ext4_extent *newext)
{
struct ext4_ext_path *curp = path;
struct ext4_extent_header *neh;
- struct ext4_extent_idx *fidx;
struct buffer_head *bh;
ext4_fsblk_t newblock;
int err = 0;
- newblock = ext4_ext_new_meta_block(handle, inode, path, newext, &err);
+ newblock = ext4_ext_new_meta_block(handle, inode, path,
+ newext, &err, flags);
if (newblock == 0)
return err;
ext4_idx_store_pblock(curp->p_idx, newblock);
neh = ext_inode_hdr(inode);
- fidx = EXT_FIRST_INDEX(neh);
ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max),
- le32_to_cpu(fidx->ei_block), idx_pblock(fidx));
+ le32_to_cpu(EXT_FIRST_INDEX(neh)->ei_block),
+ ext4_idx_pblock(EXT_FIRST_INDEX(neh)));
neh->eh_depth = cpu_to_le16(path->p_depth + 1);
err = ext4_ext_dirty(handle, inode, curp);
* if no free index is found, then it requests in-depth growing.
*/
static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,
- struct ext4_ext_path *path,
- struct ext4_extent *newext)
+ unsigned int flags,
+ struct ext4_ext_path *path,
+ struct ext4_extent *newext)
{
struct ext4_ext_path *curp;
int depth, i, err = 0;
if (EXT_HAS_FREE_INDEX(curp)) {
/* if we found index with free entry, then use that
* entry: create all needed subtree and add new leaf */
- err = ext4_ext_split(handle, inode, path, newext, i);
+ err = ext4_ext_split(handle, inode, flags, path, newext, i);
if (err)
goto out;
err = PTR_ERR(path);
} else {
/* tree is full, time to grow in depth */
- err = ext4_ext_grow_indepth(handle, inode, path, newext);
+ err = ext4_ext_grow_indepth(handle, inode, flags,
+ path, newext);
if (err)
goto out;
* returns 0 at @phys
* return value contains 0 (success) or error code
*/
-int
-ext4_ext_search_left(struct inode *inode, struct ext4_ext_path *path,
- ext4_lblk_t *logical, ext4_fsblk_t *phys)
+static int ext4_ext_search_left(struct inode *inode,
+ struct ext4_ext_path *path,
+ ext4_lblk_t *logical, ext4_fsblk_t *phys)
{
struct ext4_extent_idx *ix;
struct ext4_extent *ex;
}
*logical = le32_to_cpu(ex->ee_block) + ee_len - 1;
- *phys = ext_pblock(ex) + ee_len - 1;
+ *phys = ext4_ext_pblock(ex) + ee_len - 1;
return 0;
}
* returns 0 at @phys
* return value contains 0 (success) or error code
*/
-int
-ext4_ext_search_right(struct inode *inode, struct ext4_ext_path *path,
- ext4_lblk_t *logical, ext4_fsblk_t *phys)
+static int ext4_ext_search_right(struct inode *inode,
+ struct ext4_ext_path *path,
+ ext4_lblk_t *logical, ext4_fsblk_t *phys)
{
struct buffer_head *bh = NULL;
struct ext4_extent_header *eh;
}
}
*logical = le32_to_cpu(ex->ee_block);
- *phys = ext_pblock(ex);
+ *phys = ext4_ext_pblock(ex);
return 0;
}
/* next allocated block in this leaf */
ex++;
*logical = le32_to_cpu(ex->ee_block);
- *phys = ext_pblock(ex);
+ *phys = ext4_ext_pblock(ex);
return 0;
}
* follow it and find the closest allocated
* block to the right */
ix++;
- block = idx_pblock(ix);
+ block = ext4_idx_pblock(ix);
while (++depth < path->p_depth) {
bh = sb_bread(inode->i_sb, block);
if (bh == NULL)
return -EIO;
}
ix = EXT_FIRST_INDEX(eh);
- block = idx_pblock(ix);
+ block = ext4_idx_pblock(ix);
put_bh(bh);
}
}
ex = EXT_FIRST_EXTENT(eh);
*logical = le32_to_cpu(ex->ee_block);
- *phys = ext_pblock(ex);
+ *phys = ext4_ext_pblock(ex);
put_bh(bh);
return 0;
}
/*
* ext4_ext_next_allocated_block:
- * returns allocated block in subsequent extent or EXT_MAX_BLOCK.
+ * returns allocated block in subsequent extent or EXT_MAX_BLOCKS.
* NOTE: it considers block number from index entry as
* allocated block. Thus, index entries have to be consistent
* with leaves.
depth = path->p_depth;
if (depth == 0 && path->p_ext == NULL)
- return EXT_MAX_BLOCK;
+ return EXT_MAX_BLOCKS;
while (depth >= 0) {
if (depth == path->p_depth) {
depth--;
}
- return EXT_MAX_BLOCK;
+ return EXT_MAX_BLOCKS;
}
/*
* ext4_ext_next_leaf_block:
- * returns first allocated block from next leaf or EXT_MAX_BLOCK
+ * returns first allocated block from next leaf or EXT_MAX_BLOCKS
*/
static ext4_lblk_t ext4_ext_next_leaf_block(struct inode *inode,
struct ext4_ext_path *path)
/* zero-tree has no leaf blocks at all */
if (depth == 0)
- return EXT_MAX_BLOCK;
+ return EXT_MAX_BLOCKS;
/* go to index block */
depth--;
depth--;
}
- return EXT_MAX_BLOCK;
+ return EXT_MAX_BLOCKS;
}
/*
return 0;
#endif
- if (ext_pblock(ex1) + ext1_ee_len == ext_pblock(ex2))
+ if (ext4_ext_pblock(ex1) + ext1_ee_len == ext4_ext_pblock(ex2))
return 1;
return 0;
}
* Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
* 1 if they got merged.
*/
-int ext4_ext_try_to_merge(struct inode *inode,
- struct ext4_ext_path *path,
- struct ext4_extent *ex)
+static int ext4_ext_try_to_merge_right(struct inode *inode,
+ struct ext4_ext_path *path,
+ struct ext4_extent *ex)
{
struct ext4_extent_header *eh;
unsigned int depth, len;
return merge_done;
}
+/*
+ * This function tries to merge the @ex extent to neighbours in the tree.
+ * return 1 if merge left else 0.
+ */
+static int ext4_ext_try_to_merge(struct inode *inode,
+ struct ext4_ext_path *path,
+ struct ext4_extent *ex) {
+ struct ext4_extent_header *eh;
+ unsigned int depth;
+ int merge_done = 0;
+ int ret = 0;
+
+ depth = ext_depth(inode);
+ BUG_ON(path[depth].p_hdr == NULL);
+ eh = path[depth].p_hdr;
+
+ if (ex > EXT_FIRST_EXTENT(eh))
+ merge_done = ext4_ext_try_to_merge_right(inode, path, ex - 1);
+
+ if (!merge_done)
+ ret = ext4_ext_try_to_merge_right(inode, path, ex);
+
+ return ret;
+}
+
/*
* check if a portion of the "newext" extent overlaps with an
* existing extent.
* such that there will be no overlap, and then returns 1.
* If there is no overlap found, it returns 0.
*/
-unsigned int ext4_ext_check_overlap(struct inode *inode,
- struct ext4_extent *newext,
- struct ext4_ext_path *path)
+static unsigned int ext4_ext_check_overlap(struct inode *inode,
+ struct ext4_extent *newext,
+ struct ext4_ext_path *path)
{
ext4_lblk_t b1, b2;
unsigned int depth, len1;
*/
if (b2 < b1) {
b2 = ext4_ext_next_allocated_block(path);
- if (b2 == EXT_MAX_BLOCK)
+ if (b2 == EXT_MAX_BLOCKS)
goto out;
}
/* check for wrap through zero on extent logical start block*/
if (b1 + len1 < b1) {
- len1 = EXT_MAX_BLOCK - b1;
+ len1 = EXT_MAX_BLOCKS - b1;
newext->ee_len = cpu_to_le16(len1);
ret = 1;
}
int depth, len, err;
ext4_lblk_t next;
unsigned uninitialized = 0;
+ int flags = 0;
if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
if (ex && !(flag & EXT4_GET_BLOCKS_PRE_IO)
&& ext4_can_extents_be_merged(inode, ex, newext)) {
ext_debug("append [%d]%d block to %d:[%d]%d (from %llu)\n",
- ext4_ext_is_uninitialized(newext),
- ext4_ext_get_actual_len(newext),
- le32_to_cpu(ex->ee_block),
- ext4_ext_is_uninitialized(ex),
- ext4_ext_get_actual_len(ex), ext_pblock(ex));
+ ext4_ext_is_uninitialized(newext),
+ ext4_ext_get_actual_len(newext),
+ le32_to_cpu(ex->ee_block),
+ ext4_ext_is_uninitialized(ex),
+ ext4_ext_get_actual_len(ex),
+ ext4_ext_pblock(ex));
err = ext4_ext_get_access(handle, inode, path + depth);
if (err)
return err;
goto merge;
}
-repeat:
depth = ext_depth(inode);
eh = path[depth].p_hdr;
if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max))
/* probably next leaf has space for us? */
fex = EXT_LAST_EXTENT(eh);
- next = ext4_ext_next_leaf_block(inode, path);
- if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block)
- && next != EXT_MAX_BLOCK) {
+ next = EXT_MAX_BLOCKS;
+ if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block))
+ next = ext4_ext_next_leaf_block(inode, path);
+ if (next != EXT_MAX_BLOCKS) {
ext_debug("next leaf block - %d\n", next);
BUG_ON(npath != NULL);
npath = ext4_ext_find_extent(inode, next, NULL);
BUG_ON(npath->p_depth != path->p_depth);
eh = npath[depth].p_hdr;
if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) {
- ext_debug("next leaf isnt full(%d)\n",
+ ext_debug("next leaf isn't full(%d)\n",
le16_to_cpu(eh->eh_entries));
path = npath;
- goto repeat;
+ goto has_space;
}
ext_debug("next leaf has no free space(%d,%d)\n",
le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
* There is no free space in the found leaf.
* We're gonna add a new leaf in the tree.
*/
- err = ext4_ext_create_new_leaf(handle, inode, path, newext);
+ if (flag & EXT4_GET_BLOCKS_PUNCH_OUT_EXT)
+ flags = EXT4_MB_USE_ROOT_BLOCKS;
+ err = ext4_ext_create_new_leaf(handle, inode, flags, path, newext);
if (err)
goto cleanup;
depth = ext_depth(inode);
/* there is no extent in this leaf, create first one */
ext_debug("first extent in the leaf: %d:%llu:[%d]%d\n",
le32_to_cpu(newext->ee_block),
- ext_pblock(newext),
+ ext4_ext_pblock(newext),
ext4_ext_is_uninitialized(newext),
ext4_ext_get_actual_len(newext));
path[depth].p_ext = EXT_FIRST_EXTENT(eh);
ext_debug("insert %d:%llu:[%d]%d after: nearest 0x%p, "
"move %d from 0x%p to 0x%p\n",
le32_to_cpu(newext->ee_block),
- ext_pblock(newext),
+ ext4_ext_pblock(newext),
ext4_ext_is_uninitialized(newext),
ext4_ext_get_actual_len(newext),
nearex, len, nearex + 1, nearex + 2);
ext_debug("insert %d:%llu:[%d]%d before: nearest 0x%p, "
"move %d from 0x%p to 0x%p\n",
le32_to_cpu(newext->ee_block),
- ext_pblock(newext),
+ ext4_ext_pblock(newext),
ext4_ext_is_uninitialized(newext),
ext4_ext_get_actual_len(newext),
nearex, len, nearex + 1, nearex + 2);
le16_add_cpu(&eh->eh_entries, 1);
nearex = path[depth].p_ext;
nearex->ee_block = newext->ee_block;
- ext4_ext_store_pblock(nearex, ext_pblock(newext));
+ ext4_ext_store_pblock(nearex, ext4_ext_pblock(newext));
nearex->ee_len = newext->ee_len;
merge:
return err;
}
-int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block,
- ext4_lblk_t num, ext_prepare_callback func,
- void *cbdata)
+static int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block,
+ ext4_lblk_t num, ext_prepare_callback func,
+ void *cbdata)
{
struct ext4_ext_path *path = NULL;
struct ext4_ext_cache cbex;
BUG_ON(func == NULL);
BUG_ON(inode == NULL);
- while (block < last && block != EXT_MAX_BLOCK) {
+ while (block < last && block != EXT_MAX_BLOCKS) {
num = last - block;
/* find extent for this block */
down_read(&EXT4_I(inode)->i_data_sem);
cbex.ec_block = start;
cbex.ec_len = end - start;
cbex.ec_start = 0;
- cbex.ec_type = EXT4_EXT_CACHE_GAP;
} else {
cbex.ec_block = le32_to_cpu(ex->ee_block);
cbex.ec_len = ext4_ext_get_actual_len(ex);
- cbex.ec_start = ext_pblock(ex);
- cbex.ec_type = EXT4_EXT_CACHE_EXTENT;
+ cbex.ec_start = ext4_ext_pblock(ex);
}
if (unlikely(cbex.ec_len == 0)) {
err = -EIO;
break;
}
- err = func(inode, path, &cbex, ex, cbdata);
+ err = func(inode, next, &cbex, ex, cbdata);
ext4_ext_drop_refs(path);
if (err < 0)
static void
ext4_ext_put_in_cache(struct inode *inode, ext4_lblk_t block,
- __u32 len, ext4_fsblk_t start, int type)
+ __u32 len, ext4_fsblk_t start)
{
struct ext4_ext_cache *cex;
BUG_ON(len == 0);
spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
cex = &EXT4_I(inode)->i_cached_extent;
- cex->ec_type = type;
cex->ec_block = block;
cex->ec_len = len;
cex->ec_start = start;
if (ex == NULL) {
/* there is no extent yet, so gap is [0;-] */
lblock = 0;
- len = EXT_MAX_BLOCK;
+ len = EXT_MAX_BLOCKS;
ext_debug("cache gap(whole file):");
} else if (block < le32_to_cpu(ex->ee_block)) {
lblock = block;
}
ext_debug(" -> %u:%lu\n", lblock, len);
- ext4_ext_put_in_cache(inode, lblock, len, 0, EXT4_EXT_CACHE_GAP);
+ ext4_ext_put_in_cache(inode, lblock, len, 0);
}
-static int
-ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block,
- struct ext4_extent *ex)
-{
+/*
+ * ext4_ext_in_cache()
+ * Checks to see if the given block is in the cache.
+ * If it is, the cached extent is stored in the given
+ * cache extent pointer. If the cached extent is a hole,
+ * this routine should be used instead of
+ * ext4_ext_in_cache if the calling function needs to
+ * know the size of the hole.
+ *
+ * @inode: The files inode
+ * @block: The block to look for in the cache
+ * @ex: Pointer where the cached extent will be stored
+ * if it contains block
+ *
+ * Return 0 if cache is invalid; 1 if the cache is valid
+ */
+static int ext4_ext_check_cache(struct inode *inode, ext4_lblk_t block,
+ struct ext4_ext_cache *ex){
struct ext4_ext_cache *cex;
- int ret = EXT4_EXT_CACHE_NO;
+ struct ext4_sb_info *sbi;
+ int ret = 0;
- /*
+ /*
* We borrow i_block_reservation_lock to protect i_cached_extent
*/
spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
cex = &EXT4_I(inode)->i_cached_extent;
+ sbi = EXT4_SB(inode->i_sb);
/* has cache valid data? */
- if (cex->ec_type == EXT4_EXT_CACHE_NO)
+ if (cex->ec_len == 0)
goto errout;
- BUG_ON(cex->ec_type != EXT4_EXT_CACHE_GAP &&
- cex->ec_type != EXT4_EXT_CACHE_EXTENT);
if (in_range(block, cex->ec_block, cex->ec_len)) {
- ex->ee_block = cpu_to_le32(cex->ec_block);
- ext4_ext_store_pblock(ex, cex->ec_start);
- ex->ee_len = cpu_to_le16(cex->ec_len);
+ memcpy(ex, cex, sizeof(struct ext4_ext_cache));
ext_debug("%u cached by %u:%u:%llu\n",
block,
cex->ec_block, cex->ec_len, cex->ec_start);
- ret = cex->ec_type;
+ ret = 1;
}
errout:
+ if (!ret)
+ sbi->extent_cache_misses++;
+ else
+ sbi->extent_cache_hits++;
spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
return ret;
}
+/*
+ * ext4_ext_in_cache()
+ * Checks to see if the given block is in the cache.
+ * If it is, the cached extent is stored in the given
+ * extent pointer.
+ *
+ * @inode: The files inode
+ * @block: The block to look for in the cache
+ * @ex: Pointer where the cached extent will be stored
+ * if it contains block
+ *
+ * Return 0 if cache is invalid; 1 if the cache is valid
+ */
+static int
+ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block,
+ struct ext4_extent *ex)
+{
+ struct ext4_ext_cache cex;
+ int ret = 0;
+
+ if (ext4_ext_check_cache(inode, block, &cex)) {
+ ex->ee_block = cpu_to_le32(cex.ec_block);
+ ext4_ext_store_pblock(ex, cex.ec_start);
+ ex->ee_len = cpu_to_le16(cex.ec_len);
+ ret = 1;
+ }
+
+ return ret;
+}
+
+
/*
* ext4_ext_rm_idx:
* removes index from the index block.
/* free index block */
path--;
- leaf = idx_pblock(path->p_idx);
+ leaf = ext4_idx_pblock(path->p_idx);
if (unlikely(path->p_hdr->eh_entries == 0)) {
EXT4_ERROR_INODE(inode, "path->p_hdr->eh_entries == 0");
return -EIO;
if (err)
return err;
ext_debug("index is empty, remove it, free block %llu\n", leaf);
- ext4_free_blocks(handle, inode, 0, leaf, 1,
+ ext4_free_blocks(handle, inode, NULL, leaf, 1,
EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
return err;
}
ext4_fsblk_t start;
num = le32_to_cpu(ex->ee_block) + ee_len - from;
- start = ext_pblock(ex) + ee_len - num;
+ start = ext4_ext_pblock(ex) + ee_len - num;
ext_debug("free last %u blocks starting %llu\n", num, start);
- ext4_free_blocks(handle, inode, 0, start, num, flags);
+ ext4_free_blocks(handle, inode, NULL, start, num, flags);
} else if (from == le32_to_cpu(ex->ee_block)
&& to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
- printk(KERN_INFO "strange request: removal %u-%u from %u:%u\n",
- from, to, le32_to_cpu(ex->ee_block), ee_len);
+ /* head removal */
+ ext4_lblk_t num;
+ ext4_fsblk_t start;
+
+ num = to - from;
+ start = ext4_ext_pblock(ex);
+
+ ext_debug("free first %u blocks starting %llu\n", num, start);
+ ext4_free_blocks(handle, inode, 0, start, num, flags);
+
} else {
printk(KERN_INFO "strange request: removal(2) "
"%u-%u from %u:%u\n",
return 0;
}
+
+/*
+ * ext4_ext_rm_leaf() Removes the extents associated with the
+ * blocks appearing between "start" and "end", and splits the extents
+ * if "start" and "end" appear in the same extent
+ *
+ * @handle: The journal handle
+ * @inode: The files inode
+ * @path: The path to the leaf
+ * @start: The first block to remove
+ * @end: The last block to remove
+ */
static int
ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
- struct ext4_ext_path *path, ext4_lblk_t start)
+ struct ext4_ext_path *path, ext4_lblk_t start,
+ ext4_lblk_t end)
{
int err = 0, correct_index = 0;
int depth = ext_depth(inode), credits;
unsigned short ex_ee_len;
unsigned uninitialized = 0;
struct ext4_extent *ex;
+ struct ext4_map_blocks map;
/* the header must be checked already in ext4_ext_remove_space() */
ext_debug("truncate since %u in leaf\n", start);
path[depth].p_ext = ex;
a = ex_ee_block > start ? ex_ee_block : start;
- b = ex_ee_block + ex_ee_len - 1 < EXT_MAX_BLOCK ?
- ex_ee_block + ex_ee_len - 1 : EXT_MAX_BLOCK;
+ b = ex_ee_block+ex_ee_len - 1 < end ?
+ ex_ee_block+ex_ee_len - 1 : end;
ext_debug(" border %u:%u\n", a, b);
- if (a != ex_ee_block && b != ex_ee_block + ex_ee_len - 1) {
- block = 0;
- num = 0;
- BUG();
+ /* If this extent is beyond the end of the hole, skip it */
+ if (end <= ex_ee_block) {
+ ex--;
+ ex_ee_block = le32_to_cpu(ex->ee_block);
+ ex_ee_len = ext4_ext_get_actual_len(ex);
+ continue;
+ } else if (a != ex_ee_block &&
+ b != ex_ee_block + ex_ee_len - 1) {
+ /*
+ * If this is a truncate, then this condition should
+ * never happen because at least one of the end points
+ * needs to be on the edge of the extent.
+ */
+ if (end == EXT_MAX_BLOCKS - 1) {
+ ext_debug(" bad truncate %u:%u\n",
+ start, end);
+ block = 0;
+ num = 0;
+ err = -EIO;
+ goto out;
+ }
+ /*
+ * else this is a hole punch, so the extent needs to
+ * be split since neither edge of the hole is on the
+ * extent edge
+ */
+ else{
+ map.m_pblk = ext4_ext_pblock(ex);
+ map.m_lblk = ex_ee_block;
+ map.m_len = b - ex_ee_block;
+
+ err = ext4_split_extent(handle,
+ inode, path, &map, 0,
+ EXT4_GET_BLOCKS_PUNCH_OUT_EXT |
+ EXT4_GET_BLOCKS_PRE_IO);
+
+ if (err < 0)
+ goto out;
+
+ ex_ee_len = ext4_ext_get_actual_len(ex);
+
+ b = ex_ee_block+ex_ee_len - 1 < end ?
+ ex_ee_block+ex_ee_len - 1 : end;
+
+ /* Then remove tail of this extent */
+ block = ex_ee_block;
+ num = a - block;
+ }
} else if (a != ex_ee_block) {
/* remove tail of the extent */
block = ex_ee_block;
num = a - block;
} else if (b != ex_ee_block + ex_ee_len - 1) {
/* remove head of the extent */
- block = a;
- num = b - a;
- /* there is no "make a hole" API yet */
- BUG();
+ block = b;
+ num = ex_ee_block + ex_ee_len - b;
+
+ /*
+ * If this is a truncate, this condition
+ * should never happen
+ */
+ if (end == EXT_MAX_BLOCKS - 1) {
+ ext_debug(" bad truncate %u:%u\n",
+ start, end);
+ err = -EIO;
+ goto out;
+ }
} else {
/* remove whole extent: excellent! */
block = ex_ee_block;
num = 0;
- BUG_ON(a != ex_ee_block);
- BUG_ON(b != ex_ee_block + ex_ee_len - 1);
+ if (a != ex_ee_block) {
+ ext_debug(" bad truncate %u:%u\n",
+ start, end);
+ err = -EIO;
+ goto out;
+ }
+
+ if (b != ex_ee_block + ex_ee_len - 1) {
+ ext_debug(" bad truncate %u:%u\n",
+ start, end);
+ err = -EIO;
+ goto out;
+ }
}
/*
if (num == 0) {
/* this extent is removed; mark slot entirely unused */
ext4_ext_store_pblock(ex, 0);
- le16_add_cpu(&eh->eh_entries, -1);
+ } else if (block != ex_ee_block) {
+ /*
+ * If this was a head removal, then we need to update
+ * the physical block since it is now at a different
+ * location
+ */
+ ext4_ext_store_pblock(ex, ext4_ext_pblock(ex) + (b-a));
}
ex->ee_block = cpu_to_le32(block);
if (err)
goto out;
+ /*
+ * If the extent was completely released,
+ * we need to remove it from the leaf
+ */
+ if (num == 0) {
+ if (end != EXT_MAX_BLOCKS - 1) {
+ /*
+ * For hole punching, we need to scoot all the
+ * extents up when an extent is removed so that
+ * we dont have blank extents in the middle
+ */
+ memmove(ex, ex+1, (EXT_LAST_EXTENT(eh) - ex) *
+ sizeof(struct ext4_extent));
+
+ /* Now get rid of the one at the end */
+ memset(EXT_LAST_EXTENT(eh), 0,
+ sizeof(struct ext4_extent));
+ }
+ le16_add_cpu(&eh->eh_entries, -1);
+ }
+
ext_debug("new extent: %u:%u:%llu\n", block, num,
- ext_pblock(ex));
+ ext4_ext_pblock(ex));
ex--;
ex_ee_block = le32_to_cpu(ex->ee_block);
ex_ee_len = ext4_ext_get_actual_len(ex);
return 1;
}
-static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start)
+static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
+ ext4_lblk_t end)
{
struct super_block *sb = inode->i_sb;
int depth = ext_depth(inode);
struct ext4_ext_path *path;
handle_t *handle;
- int i = 0, err = 0;
+ int i, err;
ext_debug("truncate since %u\n", start);
if (IS_ERR(handle))
return PTR_ERR(handle);
+again:
ext4_ext_invalidate_cache(inode);
/*
* We start scanning from right side, freeing all the blocks
* after i_size and walking into the tree depth-wise.
*/
+ depth = ext_depth(inode);
path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_NOFS);
if (path == NULL) {
ext4_journal_stop(handle);
return -ENOMEM;
}
+ path[0].p_depth = depth;
path[0].p_hdr = ext_inode_hdr(inode);
if (ext4_ext_check(inode, path[0].p_hdr, depth)) {
err = -EIO;
goto out;
}
- path[0].p_depth = depth;
+ i = err = 0;
while (i >= 0 && err == 0) {
if (i == depth) {
/* this is leaf block */
- err = ext4_ext_rm_leaf(handle, inode, path, start);
+ err = ext4_ext_rm_leaf(handle, inode, path,
+ start, end);
/* root level has p_bh == NULL, brelse() eats this */
brelse(path[i].p_bh);
path[i].p_bh = NULL;
struct buffer_head *bh;
/* go to the next level */
ext_debug("move to level %d (block %llu)\n",
- i + 1, idx_pblock(path[i].p_idx));
+ i + 1, ext4_idx_pblock(path[i].p_idx));
memset(path + i + 1, 0, sizeof(*path));
- bh = sb_bread(sb, idx_pblock(path[i].p_idx));
+ bh = sb_bread(sb, ext4_idx_pblock(path[i].p_idx));
if (!bh) {
/* should we reset i_size? */
err = -EIO;
out:
ext4_ext_drop_refs(path);
kfree(path);
+ if (err == -EAGAIN)
+ goto again;
ext4_journal_stop(handle);
return err;
#endif
}
-static void bi_complete(struct bio *bio, int error)
-{
- complete((struct completion *)bio->bi_private);
-}
-
/* FIXME!! we need to try to merge to left or right after zero-out */
static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
{
+ ext4_fsblk_t ee_pblock;
+ unsigned int ee_len;
int ret;
- struct bio *bio;
- int blkbits, blocksize;
- sector_t ee_pblock;
- struct completion event;
- unsigned int ee_len, len, done, offset;
-
- blkbits = inode->i_blkbits;
- blocksize = inode->i_sb->s_blocksize;
ee_len = ext4_ext_get_actual_len(ex);
- ee_pblock = ext_pblock(ex);
-
- /* convert ee_pblock to 512 byte sectors */
- ee_pblock = ee_pblock << (blkbits - 9);
-
- while (ee_len > 0) {
-
- if (ee_len > BIO_MAX_PAGES)
- len = BIO_MAX_PAGES;
- else
- len = ee_len;
-
- bio = bio_alloc(GFP_NOIO, len);
- if (!bio)
- return -ENOMEM;
-
- bio->bi_sector = ee_pblock;
- bio->bi_bdev = inode->i_sb->s_bdev;
-
- done = 0;
- offset = 0;
- while (done < len) {
- ret = bio_add_page(bio, ZERO_PAGE(0),
- blocksize, offset);
- if (ret != blocksize) {
- /*
- * We can't add any more pages because of
- * hardware limitations. Start a new bio.
- */
- break;
- }
- done++;
- offset += blocksize;
- if (offset >= PAGE_CACHE_SIZE)
- offset = 0;
- }
+ ee_pblock = ext4_ext_pblock(ex);
- init_completion(&event);
- bio->bi_private = &event;
- bio->bi_end_io = bi_complete;
- submit_bio(WRITE, bio);
- wait_for_completion(&event);
+ ret = sb_issue_zeroout(inode->i_sb, ee_pblock, ee_len, GFP_NOFS);
+ if (ret > 0)
+ ret = 0;
- if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) {
- bio_put(bio);
- return -EIO;
- }
- bio_put(bio);
- ee_len -= done;
- ee_pblock += done << (blkbits - 9);
- }
- return 0;
+ return ret;
}
-#define EXT4_EXT_ZERO_LEN 7
/*
- * This function is called by ext4_ext_map_blocks() if someone tries to write
- * to an uninitialized extent. It may result in splitting the uninitialized
- * extent into multiple extents (upto three - one initialized and two
- * uninitialized).
- * There are three possibilities:
- * a> There is no split required: Entire extent should be initialized
- * b> Splits in two extents: Write is happening at either end of the extent
- * c> Splits in three extents: Somone is writing in middle of the extent
+ * used by extent splitting.
*/
-static int ext4_ext_convert_to_initialized(handle_t *handle,
- struct inode *inode,
- struct ext4_map_blocks *map,
- struct ext4_ext_path *path)
+#define EXT4_EXT_MAY_ZEROOUT 0x1 /* safe to zeroout if split fails \
+ due to ENOSPC */
+#define EXT4_EXT_MARK_UNINIT1 0x2 /* mark first half uninitialized */
+#define EXT4_EXT_MARK_UNINIT2 0x4 /* mark second half uninitialized */
+
+/*
+ * ext4_split_extent_at() splits an extent at given block.
+ *
+ * @handle: the journal handle
+ * @inode: the file inode
+ * @path: the path to the extent
+ * @split: the logical block where the extent is splitted.
+ * @split_flags: indicates if the extent could be zeroout if split fails, and
+ * the states(init or uninit) of new extents.
+ * @flags: flags used to insert new extent to extent tree.
+ *
+ *
+ * Splits extent [a, b] into two extents [a, @split) and [@split, b], states
+ * of which are deterimined by split_flag.
+ *
+ * There are two cases:
+ * a> the extent are splitted into two extent.
+ * b> split is not needed, and just mark the extent.
+ *
+ * return 0 on success.
+ */
+static int ext4_split_extent_at(handle_t *handle,
+ struct inode *inode,
+ struct ext4_ext_path *path,
+ ext4_lblk_t split,
+ int split_flag,
+ int flags)
{
+ ext4_fsblk_t newblock;
+ ext4_lblk_t ee_block;
struct ext4_extent *ex, newex, orig_ex;
- struct ext4_extent *ex1 = NULL;
struct ext4_extent *ex2 = NULL;
- struct ext4_extent *ex3 = NULL;
- struct ext4_extent_header *eh;
- ext4_lblk_t ee_block, eof_block;
- unsigned int allocated, ee_len, depth;
- ext4_fsblk_t newblock;
+ unsigned int ee_len, depth;
int err = 0;
- int ret = 0;
- int may_zeroout;
- ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical"
- "block %llu, max_blocks %u\n", inode->i_ino,
- (unsigned long long)map->m_lblk, map->m_len);
+ ext_debug("ext4_split_extents_at: inode %lu, logical"
+ "block %llu\n", inode->i_ino, (unsigned long long)split);
- eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
- inode->i_sb->s_blocksize_bits;
- if (eof_block < map->m_lblk + map->m_len)
- eof_block = map->m_lblk + map->m_len;
+ ext4_ext_show_leaf(inode, path);
depth = ext_depth(inode);
- eh = path[depth].p_hdr;
ex = path[depth].p_ext;
ee_block = le32_to_cpu(ex->ee_block);
ee_len = ext4_ext_get_actual_len(ex);
- allocated = ee_len - (map->m_lblk - ee_block);
- newblock = map->m_lblk - ee_block + ext_pblock(ex);
+ newblock = split - ee_block + ext4_ext_pblock(ex);
- ex2 = ex;
- orig_ex.ee_block = ex->ee_block;
- orig_ex.ee_len = cpu_to_le16(ee_len);
- ext4_ext_store_pblock(&orig_ex, ext_pblock(ex));
-
- /*
- * It is safe to convert extent to initialized via explicit
- * zeroout only if extent is fully insde i_size or new_size.
- */
- may_zeroout = ee_block + ee_len <= eof_block;
+ BUG_ON(split < ee_block || split >= (ee_block + ee_len));
err = ext4_ext_get_access(handle, inode, path + depth);
if (err)
goto out;
- /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
- if (ee_len <= 2*EXT4_EXT_ZERO_LEN && may_zeroout) {
- err = ext4_ext_zeroout(inode, &orig_ex);
- if (err)
- goto fix_extent_len;
- /* update the extent length and mark as initialized */
- ex->ee_block = orig_ex.ee_block;
- ex->ee_len = orig_ex.ee_len;
- ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
- ext4_ext_dirty(handle, inode, path + depth);
- /* zeroed the full extent */
- return allocated;
- }
-
- /* ex1: ee_block to map->m_lblk - 1 : uninitialized */
- if (map->m_lblk > ee_block) {
- ex1 = ex;
- ex1->ee_len = cpu_to_le16(map->m_lblk - ee_block);
- ext4_ext_mark_uninitialized(ex1);
- ex2 = &newex;
- }
- /*
- * for sanity, update the length of the ex2 extent before
- * we insert ex3, if ex1 is NULL. This is to avoid temporary
- * overlap of blocks.
- */
- if (!ex1 && allocated > map->m_len)
- ex2->ee_len = cpu_to_le16(map->m_len);
- /* ex3: to ee_block + ee_len : uninitialised */
- if (allocated > map->m_len) {
- unsigned int newdepth;
- /* If extent has less than EXT4_EXT_ZERO_LEN zerout directly */
- if (allocated <= EXT4_EXT_ZERO_LEN && may_zeroout) {
- /*
- * map->m_lblk == ee_block is handled by the zerouout
- * at the beginning.
- * Mark first half uninitialized.
- * Mark second half initialized and zero out the
- * initialized extent
- */
- ex->ee_block = orig_ex.ee_block;
- ex->ee_len = cpu_to_le16(ee_len - allocated);
- ext4_ext_mark_uninitialized(ex);
- ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
- ext4_ext_dirty(handle, inode, path + depth);
-
- ex3 = &newex;
- ex3->ee_block = cpu_to_le32(map->m_lblk);
- ext4_ext_store_pblock(ex3, newblock);
- ex3->ee_len = cpu_to_le16(allocated);
- err = ext4_ext_insert_extent(handle, inode, path,
- ex3, 0);
- if (err == -ENOSPC) {
- err = ext4_ext_zeroout(inode, &orig_ex);
- if (err)
- goto fix_extent_len;
- ex->ee_block = orig_ex.ee_block;
- ex->ee_len = orig_ex.ee_len;
- ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
- ext4_ext_dirty(handle, inode, path + depth);
- /* blocks available from map->m_lblk */
- return allocated;
-
- } else if (err)
- goto fix_extent_len;
-
- /*
- * We need to zero out the second half because
- * an fallocate request can update file size and
- * converting the second half to initialized extent
- * implies that we can leak some junk data to user
- * space.
- */
- err = ext4_ext_zeroout(inode, ex3);
- if (err) {
- /*
- * We should actually mark the
- * second half as uninit and return error
- * Insert would have changed the extent
- */
- depth = ext_depth(inode);
- ext4_ext_drop_refs(path);
- path = ext4_ext_find_extent(inode, map->m_lblk,
- path);
- if (IS_ERR(path)) {
- err = PTR_ERR(path);
- return err;
- }
- /* get the second half extent details */
- ex = path[depth].p_ext;
- err = ext4_ext_get_access(handle, inode,
- path + depth);
- if (err)
- return err;
- ext4_ext_mark_uninitialized(ex);
- ext4_ext_dirty(handle, inode, path + depth);
- return err;
- }
- /* zeroed the second half */
- return allocated;
- }
- ex3 = &newex;
- ex3->ee_block = cpu_to_le32(map->m_lblk + map->m_len);
- ext4_ext_store_pblock(ex3, newblock + map->m_len);
- ex3->ee_len = cpu_to_le16(allocated - map->m_len);
- ext4_ext_mark_uninitialized(ex3);
- err = ext4_ext_insert_extent(handle, inode, path, ex3, 0);
- if (err == -ENOSPC && may_zeroout) {
- err = ext4_ext_zeroout(inode, &orig_ex);
- if (err)
- goto fix_extent_len;
- /* update the extent length and mark as initialized */
- ex->ee_block = orig_ex.ee_block;
- ex->ee_len = orig_ex.ee_len;
- ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
- ext4_ext_dirty(handle, inode, path + depth);
- /* zeroed the full extent */
- /* blocks available from map->m_lblk */
- return allocated;
-
- } else if (err)
- goto fix_extent_len;
- /*
- * The depth, and hence eh & ex might change
- * as part of the insert above.
- */
- newdepth = ext_depth(inode);
+ if (split == ee_block) {
/*
- * update the extent length after successful insert of the
- * split extent
+ * case b: block @split is the block that the extent begins with
+ * then we just change the state of the extent, and splitting
+ * is not needed.
*/
- ee_len -= ext4_ext_get_actual_len(ex3);
- orig_ex.ee_len = cpu_to_le16(ee_len);
- may_zeroout = ee_block + ee_len <= eof_block;
+ if (split_flag & EXT4_EXT_MARK_UNINIT2)
+ ext4_ext_mark_uninitialized(ex);
+ else
+ ext4_ext_mark_initialized(ex);
- depth = newdepth;
- ext4_ext_drop_refs(path);
- path = ext4_ext_find_extent(inode, map->m_lblk, path);
- if (IS_ERR(path)) {
- err = PTR_ERR(path);
- goto out;
- }
- eh = path[depth].p_hdr;
- ex = path[depth].p_ext;
- if (ex2 != &newex)
- ex2 = ex;
+ if (!(flags & EXT4_GET_BLOCKS_PRE_IO))
+ ext4_ext_try_to_merge(inode, path, ex);
- err = ext4_ext_get_access(handle, inode, path + depth);
- if (err)
- goto out;
+ err = ext4_ext_dirty(handle, inode, path + depth);
+ goto out;
+ }
- allocated = map->m_len;
+ /* case a */
+ memcpy(&orig_ex, ex, sizeof(orig_ex));
+ ex->ee_len = cpu_to_le16(split - ee_block);
+ if (split_flag & EXT4_EXT_MARK_UNINIT1)
+ ext4_ext_mark_uninitialized(ex);
- /* If extent has less than EXT4_EXT_ZERO_LEN and we are trying
- * to insert a extent in the middle zerout directly
- * otherwise give the extent a chance to merge to left
- */
- if (le16_to_cpu(orig_ex.ee_len) <= EXT4_EXT_ZERO_LEN &&
- map->m_lblk != ee_block && may_zeroout) {
- err = ext4_ext_zeroout(inode, &orig_ex);
- if (err)
- goto fix_extent_len;
- /* update the extent length and mark as initialized */
- ex->ee_block = orig_ex.ee_block;
- ex->ee_len = orig_ex.ee_len;
- ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
- ext4_ext_dirty(handle, inode, path + depth);
- /* zero out the first half */
- /* blocks available from map->m_lblk */
- return allocated;
- }
- }
- /*
- * If there was a change of depth as part of the
- * insertion of ex3 above, we need to update the length
- * of the ex1 extent again here
- */
- if (ex1 && ex1 != ex) {
- ex1 = ex;
- ex1->ee_len = cpu_to_le16(map->m_lblk - ee_block);
- ext4_ext_mark_uninitialized(ex1);
- ex2 = &newex;
- }
- /* ex2: map->m_lblk to map->m_lblk + maxblocks-1 : initialised */
- ex2->ee_block = cpu_to_le32(map->m_lblk);
- ext4_ext_store_pblock(ex2, newblock);
- ex2->ee_len = cpu_to_le16(allocated);
- if (ex2 != ex)
- goto insert;
/*
- * New (initialized) extent starts from the first block
- * in the current extent. i.e., ex2 == ex
- * We have to see if it can be merged with the extent
- * on the left.
+ * path may lead to new leaf, not to original leaf any more
+ * after ext4_ext_insert_extent() returns,
*/
- if (ex2 > EXT_FIRST_EXTENT(eh)) {
- /*
- * To merge left, pass "ex2 - 1" to try_to_merge(),
- * since it merges towards right _only_.
- */
- ret = ext4_ext_try_to_merge(inode, path, ex2 - 1);
- if (ret) {
- err = ext4_ext_correct_indexes(handle, inode, path);
- if (err)
- goto out;
- depth = ext_depth(inode);
- ex2--;
- }
- }
- /*
- * Try to Merge towards right. This might be required
- * only when the whole extent is being written to.
- * i.e. ex2 == ex and ex3 == NULL.
- */
- if (!ex3) {
- ret = ext4_ext_try_to_merge(inode, path, ex2);
- if (ret) {
- err = ext4_ext_correct_indexes(handle, inode, path);
- if (err)
- goto out;
- }
- }
- /* Mark modified extent as dirty */
err = ext4_ext_dirty(handle, inode, path + depth);
- goto out;
-insert:
- err = ext4_ext_insert_extent(handle, inode, path, &newex, 0);
- if (err == -ENOSPC && may_zeroout) {
- err = ext4_ext_zeroout(inode, &orig_ex);
+ if (err)
+ goto fix_extent_len;
+
+ ex2 = &newex;
+ ex2->ee_block = cpu_to_le32(split);
+ ex2->ee_len = cpu_to_le16(ee_len - (split - ee_block));
+ ext4_ext_store_pblock(ex2, newblock);
+ if (split_flag & EXT4_EXT_MARK_UNINIT2)
+ ext4_ext_mark_uninitialized(ex2);
+
+ err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
+ if (err == -ENOSPC && (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
+ err = ext4_ext_zeroout(inode, &orig_ex);
if (err)
goto fix_extent_len;
/* update the extent length and mark as initialized */
- ex->ee_block = orig_ex.ee_block;
- ex->ee_len = orig_ex.ee_len;
- ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
- ext4_ext_dirty(handle, inode, path + depth);
- /* zero out the first half */
- return allocated;
+ ex->ee_len = cpu_to_le32(ee_len);
+ ext4_ext_try_to_merge(inode, path, ex);
+ err = ext4_ext_dirty(handle, inode, path + depth);
+ goto out;
} else if (err)
goto fix_extent_len;
+
out:
ext4_ext_show_leaf(inode, path);
- return err ? err : allocated;
+ return err;
fix_extent_len:
- ex->ee_block = orig_ex.ee_block;
- ex->ee_len = orig_ex.ee_len;
- ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
- ext4_ext_mark_uninitialized(ex);
+ ex->ee_len = orig_ex.ee_len;
ext4_ext_dirty(handle, inode, path + depth);
return err;
}
/*
- * This function is called by ext4_ext_map_blocks() from
- * ext4_get_blocks_dio_write() when DIO to write
- * to an uninitialized extent.
+ * ext4_split_extents() splits an extent and mark extent which is covered
+ * by @map as split_flags indicates
*
- * Writing to an uninitized extent may result in splitting the uninitialized
- * extent into multiple /intialized unintialized extents (up to three)
+ * It may result in splitting the extent into multiple extents (upto three)
* There are three possibilities:
- * a> There is no split required: Entire extent should be uninitialized
+ * a> There is no split required
+ * b> Splits in two extents: Split is happening at either end of the extent
+ * c> Splits in three extents: Somone is splitting in middle of the extent
+ *
+ */
+static int ext4_split_extent(handle_t *handle,
+ struct inode *inode,
+ struct ext4_ext_path *path,
+ struct ext4_map_blocks *map,
+ int split_flag,
+ int flags)
+{
+ ext4_lblk_t ee_block;
+ struct ext4_extent *ex;
+ unsigned int ee_len, depth;
+ int err = 0;
+ int uninitialized;
+ int split_flag1, flags1;
+
+ depth = ext_depth(inode);
+ ex = path[depth].p_ext;
+ ee_block = le32_to_cpu(ex->ee_block);
+ ee_len = ext4_ext_get_actual_len(ex);
+ uninitialized = ext4_ext_is_uninitialized(ex);
+
+ if (map->m_lblk + map->m_len < ee_block + ee_len) {
+ split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT ?
+ EXT4_EXT_MAY_ZEROOUT : 0;
+ flags1 = flags | EXT4_GET_BLOCKS_PRE_IO;
+ if (uninitialized)
+ split_flag1 |= EXT4_EXT_MARK_UNINIT1 |
+ EXT4_EXT_MARK_UNINIT2;
+ err = ext4_split_extent_at(handle, inode, path,
+ map->m_lblk + map->m_len, split_flag1, flags1);
+ if (err)
+ goto out;
+ }
+
+ ext4_ext_drop_refs(path);
+ path = ext4_ext_find_extent(inode, map->m_lblk, path);
+ if (IS_ERR(path))
+ return PTR_ERR(path);
+
+ if (map->m_lblk >= ee_block) {
+ split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT ?
+ EXT4_EXT_MAY_ZEROOUT : 0;
+ if (uninitialized)
+ split_flag1 |= EXT4_EXT_MARK_UNINIT1;
+ if (split_flag & EXT4_EXT_MARK_UNINIT2)
+ split_flag1 |= EXT4_EXT_MARK_UNINIT2;
+ err = ext4_split_extent_at(handle, inode, path,
+ map->m_lblk, split_flag1, flags);
+ if (err)
+ goto out;
+ }
+
+ ext4_ext_show_leaf(inode, path);
+out:
+ return err ? err : map->m_len;
+}
+
+#define EXT4_EXT_ZERO_LEN 7
+/*
+ * This function is called by ext4_ext_map_blocks() if someone tries to write
+ * to an uninitialized extent. It may result in splitting the uninitialized
+ * extent into multiple extents (up to three - one initialized and two
+ * uninitialized).
+ * There are three possibilities:
+ * a> There is no split required: Entire extent should be initialized
* b> Splits in two extents: Write is happening at either end of the extent
* c> Splits in three extents: Somone is writing in middle of the extent
- *
- * One of more index blocks maybe needed if the extent tree grow after
- * the unintialized extent split. To prevent ENOSPC occur at the IO
- * complete, we need to split the uninitialized extent before DIO submit
- * the IO. The uninitilized extent called at this time will be split
- * into three uninitialized extent(at most). After IO complete, the part
- * being filled will be convert to initialized by the end_io callback function
- * via ext4_convert_unwritten_extents().
- *
- * Returns the size of uninitialized extent to be written on success.
*/
-static int ext4_split_unwritten_extents(handle_t *handle,
- struct inode *inode,
- struct ext4_map_blocks *map,
- struct ext4_ext_path *path,
- int flags)
+static int ext4_ext_convert_to_initialized(handle_t *handle,
+ struct inode *inode,
+ struct ext4_map_blocks *map,
+ struct ext4_ext_path *path)
{
- struct ext4_extent *ex, newex, orig_ex;
- struct ext4_extent *ex1 = NULL;
- struct ext4_extent *ex2 = NULL;
- struct ext4_extent *ex3 = NULL;
- struct ext4_extent_header *eh;
+ struct ext4_map_blocks split_map;
+ struct ext4_extent zero_ex;
+ struct ext4_extent *ex;
ext4_lblk_t ee_block, eof_block;
unsigned int allocated, ee_len, depth;
- ext4_fsblk_t newblock;
int err = 0;
- int may_zeroout;
+ int split_flag = 0;
- ext_debug("ext4_split_unwritten_extents: inode %lu, logical"
+ ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical"
"block %llu, max_blocks %u\n", inode->i_ino,
(unsigned long long)map->m_lblk, map->m_len);
eof_block = map->m_lblk + map->m_len;
depth = ext_depth(inode);
- eh = path[depth].p_hdr;
ex = path[depth].p_ext;
ee_block = le32_to_cpu(ex->ee_block);
ee_len = ext4_ext_get_actual_len(ex);
allocated = ee_len - (map->m_lblk - ee_block);
- newblock = map->m_lblk - ee_block + ext_pblock(ex);
-
- ex2 = ex;
- orig_ex.ee_block = ex->ee_block;
- orig_ex.ee_len = cpu_to_le16(ee_len);
- ext4_ext_store_pblock(&orig_ex, ext_pblock(ex));
+ WARN_ON(map->m_lblk < ee_block);
/*
* It is safe to convert extent to initialized via explicit
* zeroout only if extent is fully insde i_size or new_size.
*/
- may_zeroout = ee_block + ee_len <= eof_block;
+ split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
- /*
- * If the uninitialized extent begins at the same logical
- * block where the write begins, and the write completely
- * covers the extent, then we don't need to split it.
- */
- if ((map->m_lblk == ee_block) && (allocated <= map->m_len))
- return allocated;
+ /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
+ if (ee_len <= 2*EXT4_EXT_ZERO_LEN &&
+ (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
+ err = ext4_ext_zeroout(inode, ex);
+ if (err)
+ goto out;
- err = ext4_ext_get_access(handle, inode, path + depth);
- if (err)
+ err = ext4_ext_get_access(handle, inode, path + depth);
+ if (err)
+ goto out;
+ ext4_ext_mark_initialized(ex);
+ ext4_ext_try_to_merge(inode, path, ex);
+ err = ext4_ext_dirty(handle, inode, path + depth);
goto out;
- /* ex1: ee_block to map->m_lblk - 1 : uninitialized */
- if (map->m_lblk > ee_block) {
- ex1 = ex;
- ex1->ee_len = cpu_to_le16(map->m_lblk - ee_block);
- ext4_ext_mark_uninitialized(ex1);
- ex2 = &newex;
}
+
/*
- * for sanity, update the length of the ex2 extent before
- * we insert ex3, if ex1 is NULL. This is to avoid temporary
- * overlap of blocks.
+ * four cases:
+ * 1. split the extent into three extents.
+ * 2. split the extent into two extents, zeroout the first half.
+ * 3. split the extent into two extents, zeroout the second half.
+ * 4. split the extent into two extents with out zeroout.
*/
- if (!ex1 && allocated > map->m_len)
- ex2->ee_len = cpu_to_le16(map->m_len);
- /* ex3: to ee_block + ee_len : uninitialised */
+ split_map.m_lblk = map->m_lblk;
+ split_map.m_len = map->m_len;
+
if (allocated > map->m_len) {
- unsigned int newdepth;
- ex3 = &newex;
- ex3->ee_block = cpu_to_le32(map->m_lblk + map->m_len);
- ext4_ext_store_pblock(ex3, newblock + map->m_len);
- ex3->ee_len = cpu_to_le16(allocated - map->m_len);
- ext4_ext_mark_uninitialized(ex3);
- err = ext4_ext_insert_extent(handle, inode, path, ex3, flags);
- if (err == -ENOSPC && may_zeroout) {
- err = ext4_ext_zeroout(inode, &orig_ex);
+ if (allocated <= EXT4_EXT_ZERO_LEN &&
+ (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
+ /* case 3 */
+ zero_ex.ee_block =
+ cpu_to_le32(map->m_lblk);
+ zero_ex.ee_len = cpu_to_le16(allocated);
+ ext4_ext_store_pblock(&zero_ex,
+ ext4_ext_pblock(ex) + map->m_lblk - ee_block);
+ err = ext4_ext_zeroout(inode, &zero_ex);
if (err)
- goto fix_extent_len;
- /* update the extent length and mark as initialized */
- ex->ee_block = orig_ex.ee_block;
- ex->ee_len = orig_ex.ee_len;
- ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
- ext4_ext_dirty(handle, inode, path + depth);
- /* zeroed the full extent */
- /* blocks available from map->m_lblk */
- return allocated;
-
- } else if (err)
- goto fix_extent_len;
- /*
- * The depth, and hence eh & ex might change
- * as part of the insert above.
- */
- newdepth = ext_depth(inode);
- /*
- * update the extent length after successful insert of the
- * split extent
- */
- ee_len -= ext4_ext_get_actual_len(ex3);
- orig_ex.ee_len = cpu_to_le16(ee_len);
- may_zeroout = ee_block + ee_len <= eof_block;
+ goto out;
+ split_map.m_lblk = map->m_lblk;
+ split_map.m_len = allocated;
+ } else if ((map->m_lblk - ee_block + map->m_len <
+ EXT4_EXT_ZERO_LEN) &&
+ (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
+ /* case 2 */
+ if (map->m_lblk != ee_block) {
+ zero_ex.ee_block = ex->ee_block;
+ zero_ex.ee_len = cpu_to_le16(map->m_lblk -
+ ee_block);
+ ext4_ext_store_pblock(&zero_ex,
+ ext4_ext_pblock(ex));
+ err = ext4_ext_zeroout(inode, &zero_ex);
+ if (err)
+ goto out;
+ }
- depth = newdepth;
- ext4_ext_drop_refs(path);
- path = ext4_ext_find_extent(inode, map->m_lblk, path);
- if (IS_ERR(path)) {
- err = PTR_ERR(path);
- goto out;
+ split_map.m_lblk = ee_block;
+ split_map.m_len = map->m_lblk - ee_block + map->m_len;
+ allocated = map->m_len;
}
- eh = path[depth].p_hdr;
- ex = path[depth].p_ext;
- if (ex2 != &newex)
- ex2 = ex;
+ }
- err = ext4_ext_get_access(handle, inode, path + depth);
- if (err)
- goto out;
+ allocated = ext4_split_extent(handle, inode, path,
+ &split_map, split_flag, 0);
+ if (allocated < 0)
+ err = allocated;
- allocated = map->m_len;
- }
- /*
- * If there was a change of depth as part of the
- * insertion of ex3 above, we need to update the length
- * of the ex1 extent again here
- */
- if (ex1 && ex1 != ex) {
- ex1 = ex;
- ex1->ee_len = cpu_to_le16(map->m_lblk - ee_block);
- ext4_ext_mark_uninitialized(ex1);
- ex2 = &newex;
- }
- /*
- * ex2: map->m_lblk to map->m_lblk + map->m_len-1 : to be written
- * using direct I/O, uninitialised still.
- */
- ex2->ee_block = cpu_to_le32(map->m_lblk);
- ext4_ext_store_pblock(ex2, newblock);
- ex2->ee_len = cpu_to_le16(allocated);
- ext4_ext_mark_uninitialized(ex2);
- if (ex2 != ex)
- goto insert;
- /* Mark modified extent as dirty */
- err = ext4_ext_dirty(handle, inode, path + depth);
- ext_debug("out here\n");
- goto out;
-insert:
- err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
- if (err == -ENOSPC && may_zeroout) {
- err = ext4_ext_zeroout(inode, &orig_ex);
- if (err)
- goto fix_extent_len;
- /* update the extent length and mark as initialized */
- ex->ee_block = orig_ex.ee_block;
- ex->ee_len = orig_ex.ee_len;
- ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
- ext4_ext_dirty(handle, inode, path + depth);
- /* zero out the first half */
- return allocated;
- } else if (err)
- goto fix_extent_len;
out:
- ext4_ext_show_leaf(inode, path);
return err ? err : allocated;
+}
-fix_extent_len:
- ex->ee_block = orig_ex.ee_block;
- ex->ee_len = orig_ex.ee_len;
- ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
- ext4_ext_mark_uninitialized(ex);
- ext4_ext_dirty(handle, inode, path + depth);
- return err;
+/*
+ * This function is called by ext4_ext_map_blocks() from
+ * ext4_get_blocks_dio_write() when DIO to write
+ * to an uninitialized extent.
+ *
+ * Writing to an uninitialized extent may result in splitting the uninitialized
+ * extent into multiple /initialized uninitialized extents (up to three)
+ * There are three possibilities:
+ * a> There is no split required: Entire extent should be uninitialized
+ * b> Splits in two extents: Write is happening at either end of the extent
+ * c> Splits in three extents: Somone is writing in middle of the extent
+ *
+ * One of more index blocks maybe needed if the extent tree grow after
+ * the uninitialized extent split. To prevent ENOSPC occur at the IO
+ * complete, we need to split the uninitialized extent before DIO submit
+ * the IO. The uninitialized extent called at this time will be split
+ * into three uninitialized extent(at most). After IO complete, the part
+ * being filled will be convert to initialized by the end_io callback function
+ * via ext4_convert_unwritten_extents().
+ *
+ * Returns the size of uninitialized extent to be written on success.
+ */
+static int ext4_split_unwritten_extents(handle_t *handle,
+ struct inode *inode,
+ struct ext4_map_blocks *map,
+ struct ext4_ext_path *path,
+ int flags)
+{
+ ext4_lblk_t eof_block;
+ ext4_lblk_t ee_block;
+ struct ext4_extent *ex;
+ unsigned int ee_len;
+ int split_flag = 0, depth;
+
+ ext_debug("ext4_split_unwritten_extents: inode %lu, logical"
+ "block %llu, max_blocks %u\n", inode->i_ino,
+ (unsigned long long)map->m_lblk, map->m_len);
+
+ eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
+ inode->i_sb->s_blocksize_bits;
+ if (eof_block < map->m_lblk + map->m_len)
+ eof_block = map->m_lblk + map->m_len;
+ /*
+ * It is safe to convert extent to initialized via explicit
+ * zeroout only if extent is fully insde i_size or new_size.
+ */
+ depth = ext_depth(inode);
+ ex = path[depth].p_ext;
+ ee_block = le32_to_cpu(ex->ee_block);
+ ee_len = ext4_ext_get_actual_len(ex);
+
+ split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
+ split_flag |= EXT4_EXT_MARK_UNINIT2;
+
+ flags |= EXT4_GET_BLOCKS_PRE_IO;
+ return ext4_split_extent(handle, inode, path, map, split_flag, flags);
}
+
static int ext4_convert_unwritten_extents_endio(handle_t *handle,
struct inode *inode,
struct ext4_ext_path *path)
{
struct ext4_extent *ex;
- struct ext4_extent_header *eh;
int depth;
int err = 0;
- int ret = 0;
depth = ext_depth(inode);
- eh = path[depth].p_hdr;
ex = path[depth].p_ext;
+ ext_debug("ext4_convert_unwritten_extents_endio: inode %lu, logical"
+ "block %llu, max_blocks %u\n", inode->i_ino,
+ (unsigned long long)le32_to_cpu(ex->ee_block),
+ ext4_ext_get_actual_len(ex));
+
err = ext4_ext_get_access(handle, inode, path + depth);
if (err)
goto out;
/* first mark the extent as initialized */
ext4_ext_mark_initialized(ex);
- /*
- * We have to see if it can be merged with the extent
- * on the left.
- */
- if (ex > EXT_FIRST_EXTENT(eh)) {
- /*
- * To merge left, pass "ex - 1" to try_to_merge(),
- * since it merges towards right _only_.
- */
- ret = ext4_ext_try_to_merge(inode, path, ex - 1);
- if (ret) {
- err = ext4_ext_correct_indexes(handle, inode, path);
- if (err)
- goto out;
- depth = ext_depth(inode);
- ex--;
- }
- }
- /*
- * Try to Merge towards right.
+ /* note: ext4_ext_correct_indexes() isn't needed here because
+ * borders are not changed
*/
- ret = ext4_ext_try_to_merge(inode, path, ex);
- if (ret) {
- err = ext4_ext_correct_indexes(handle, inode, path);
- if (err)
- goto out;
- depth = ext_depth(inode);
- }
+ ext4_ext_try_to_merge(inode, path, ex);
+
/* Mark modified extent as dirty */
err = ext4_ext_dirty(handle, inode, path + depth);
out:
unmap_underlying_metadata(bdev, block + i);
}
+/*
+ * Handle EOFBLOCKS_FL flag, clearing it if necessary
+ */
+static int check_eofblocks_fl(handle_t *handle, struct inode *inode,
+ ext4_lblk_t lblk,
+ struct ext4_ext_path *path,
+ unsigned int len)
+{
+ int i, depth;
+ struct ext4_extent_header *eh;
+ struct ext4_extent *last_ex;
+
+ if (!ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))
+ return 0;
+
+ depth = ext_depth(inode);
+ eh = path[depth].p_hdr;
+
+ if (unlikely(!eh->eh_entries)) {
+ EXT4_ERROR_INODE(inode, "eh->eh_entries == 0 and "
+ "EOFBLOCKS_FL set");
+ return -EIO;
+ }
+ last_ex = EXT_LAST_EXTENT(eh);
+ /*
+ * We should clear the EOFBLOCKS_FL flag if we are writing the
+ * last block in the last extent in the file. We test this by
+ * first checking to see if the caller to
+ * ext4_ext_get_blocks() was interested in the last block (or
+ * a block beyond the last block) in the current extent. If
+ * this turns out to be false, we can bail out from this
+ * function immediately.
+ */
+ if (lblk + len < le32_to_cpu(last_ex->ee_block) +
+ ext4_ext_get_actual_len(last_ex))
+ return 0;
+ /*
+ * If the caller does appear to be planning to write at or
+ * beyond the end of the current extent, we then test to see
+ * if the current extent is the last extent in the file, by
+ * checking to make sure it was reached via the rightmost node
+ * at each level of the tree.
+ */
+ for (i = depth-1; i >= 0; i--)
+ if (path[i].p_idx != EXT_LAST_INDEX(path[i].p_hdr))
+ return 0;
+ ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
+ return ext4_mark_inode_dirty(handle, inode);
+}
+
static int
ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
struct ext4_map_blocks *map,
path, flags);
/*
* Flag the inode(non aio case) or end_io struct (aio case)
- * that this IO needs to convertion to written when IO is
+ * that this IO needs to conversion to written when IO is
* completed
*/
- if (io)
- io->flag = EXT4_IO_UNWRITTEN;
- else
+ if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) {
+ io->flag = EXT4_IO_END_UNWRITTEN;
+ atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
+ } else
ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
if (ext4_should_dioread_nolock(inode))
map->m_flags |= EXT4_MAP_UNINIT;
if ((flags & EXT4_GET_BLOCKS_CONVERT)) {
ret = ext4_convert_unwritten_extents_endio(handle, inode,
path);
- if (ret >= 0)
+ if (ret >= 0) {
ext4_update_inode_fsync_trans(handle, inode, 1);
+ err = check_eofblocks_fl(handle, inode, map->m_lblk,
+ path, map->m_len);
+ } else
+ err = ret;
goto out2;
}
/* buffered IO case */
/* buffered write, writepage time, convert*/
ret = ext4_ext_convert_to_initialized(handle, inode, map, path);
- if (ret >= 0)
+ if (ret >= 0) {
ext4_update_inode_fsync_trans(handle, inode, 1);
+ err = check_eofblocks_fl(handle, inode, map->m_lblk, path,
+ map->m_len);
+ if (err < 0)
+ goto out2;
+ }
+
out:
if (ret <= 0) {
err = ret;
}
return err ? err : allocated;
}
+
/*
* Block allocation/map/preallocation routine for extents based files
*
struct ext4_map_blocks *map, int flags)
{
struct ext4_ext_path *path = NULL;
- struct ext4_extent_header *eh;
- struct ext4_extent newex, *ex, *last_ex;
- ext4_fsblk_t newblock;
- int err = 0, depth, ret, cache_type;
+ struct ext4_extent newex, *ex;
+ ext4_fsblk_t newblock = 0;
+ int err = 0, depth, ret;
unsigned int allocated = 0;
+ unsigned int punched_out = 0;
+ unsigned int result = 0;
struct ext4_allocation_request ar;
ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
+ struct ext4_map_blocks punch_map;
ext_debug("blocks %u/%u requested for inode %lu\n",
map->m_lblk, map->m_len, inode->i_ino);
+ trace_ext4_ext_map_blocks_enter(inode, map->m_lblk, map->m_len, flags);
/* check in cache */
- cache_type = ext4_ext_in_cache(inode, map->m_lblk, &newex);
- if (cache_type) {
- if (cache_type == EXT4_EXT_CACHE_GAP) {
+ if (ext4_ext_in_cache(inode, map->m_lblk, &newex) &&
+ ((flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) == 0)) {
+ if (!newex.ee_start_lo && !newex.ee_start_hi) {
if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
/*
* block isn't allocated yet and
goto out2;
}
/* we should allocate requested block */
- } else if (cache_type == EXT4_EXT_CACHE_EXTENT) {
+ } else {
/* block is already allocated */
newblock = map->m_lblk
- le32_to_cpu(newex.ee_block)
- + ext_pblock(&newex);
+ + ext4_ext_pblock(&newex);
/* number of remaining blocks in the extent */
allocated = ext4_ext_get_actual_len(&newex) -
(map->m_lblk - le32_to_cpu(newex.ee_block));
goto out;
- } else {
- BUG();
}
}
err = -EIO;
goto out2;
}
- eh = path[depth].p_hdr;
ex = path[depth].p_ext;
if (ex) {
ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
- ext4_fsblk_t ee_start = ext_pblock(ex);
+ ext4_fsblk_t ee_start = ext4_ext_pblock(ex);
unsigned short ee_len;
/*
ext_debug("%u fit into %u:%d -> %llu\n", map->m_lblk,
ee_block, ee_len, newblock);
- /* Do not put uninitialized extent in the cache */
- if (!ext4_ext_is_uninitialized(ex)) {
- ext4_ext_put_in_cache(inode, ee_block,
- ee_len, ee_start,
- EXT4_EXT_CACHE_EXTENT);
- goto out;
+ if ((flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) == 0) {
+ /*
+ * Do not put uninitialized extent
+ * in the cache
+ */
+ if (!ext4_ext_is_uninitialized(ex)) {
+ ext4_ext_put_in_cache(inode, ee_block,
+ ee_len, ee_start);
+ goto out;
+ }
+ ret = ext4_ext_handle_uninitialized_extents(
+ handle, inode, map, path, flags,
+ allocated, newblock);
+ return ret;
}
- ret = ext4_ext_handle_uninitialized_extents(handle,
- inode, map, path, flags, allocated,
- newblock);
- return ret;
+
+ /*
+ * Punch out the map length, but only to the
+ * end of the extent
+ */
+ punched_out = allocated < map->m_len ?
+ allocated : map->m_len;
+
+ /*
+ * Sense extents need to be converted to
+ * uninitialized, they must fit in an
+ * uninitialized extent
+ */
+ if (punched_out > EXT_UNINIT_MAX_LEN)
+ punched_out = EXT_UNINIT_MAX_LEN;
+
+ punch_map.m_lblk = map->m_lblk;
+ punch_map.m_pblk = newblock;
+ punch_map.m_len = punched_out;
+ punch_map.m_flags = 0;
+
+ /* Check to see if the extent needs to be split */
+ if (punch_map.m_len != ee_len ||
+ punch_map.m_lblk != ee_block) {
+
+ ret = ext4_split_extent(handle, inode,
+ path, &punch_map, 0,
+ EXT4_GET_BLOCKS_PUNCH_OUT_EXT |
+ EXT4_GET_BLOCKS_PRE_IO);
+
+ if (ret < 0) {
+ err = ret;
+ goto out2;
+ }
+ /*
+ * find extent for the block at
+ * the start of the hole
+ */
+ ext4_ext_drop_refs(path);
+ kfree(path);
+
+ path = ext4_ext_find_extent(inode,
+ map->m_lblk, NULL);
+ if (IS_ERR(path)) {
+ err = PTR_ERR(path);
+ path = NULL;
+ goto out2;
+ }
+
+ depth = ext_depth(inode);
+ ex = path[depth].p_ext;
+ ee_len = ext4_ext_get_actual_len(ex);
+ ee_block = le32_to_cpu(ex->ee_block);
+ ee_start = ext4_ext_pblock(ex);
+
+ }
+
+ ext4_ext_mark_uninitialized(ex);
+
+ err = ext4_ext_remove_space(inode, map->m_lblk,
+ map->m_lblk + punched_out);
+
+ goto out2;
}
}
else
/* disable in-core preallocation for non-regular files */
ar.flags = 0;
+ if (flags & EXT4_GET_BLOCKS_NO_NORMALIZE)
+ ar.flags |= EXT4_MB_HINT_NOPREALLOC;
newblock = ext4_mb_new_blocks(handle, &ar, &err);
if (!newblock)
goto out2;
ext4_ext_mark_uninitialized(&newex);
/*
* io_end structure was created for every IO write to an
- * uninitialized extent. To avoid unecessary conversion,
+ * uninitialized extent. To avoid unnecessary conversion,
* here we flag the IO that really needs the conversion.
* For non asycn direct IO case, flag the inode state
- * that we need to perform convertion when IO is done.
+ * that we need to perform conversion when IO is done.
*/
if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
- if (io)
- io->flag = EXT4_IO_UNWRITTEN;
- else
+ if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) {
+ io->flag = EXT4_IO_END_UNWRITTEN;
+ atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
+ } else
ext4_set_inode_state(inode,
EXT4_STATE_DIO_UNWRITTEN);
}
map->m_flags |= EXT4_MAP_UNINIT;
}
- if (unlikely(ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))) {
- if (unlikely(!eh->eh_entries)) {
- EXT4_ERROR_INODE(inode,
- "eh->eh_entries == 0 and "
- "EOFBLOCKS_FL set");
- err = -EIO;
- goto out2;
- }
- last_ex = EXT_LAST_EXTENT(eh);
- if (map->m_lblk + ar.len > le32_to_cpu(last_ex->ee_block)
- + ext4_ext_get_actual_len(last_ex))
- ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
- }
- err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
+ err = check_eofblocks_fl(handle, inode, map->m_lblk, path, ar.len);
+ if (!err)
+ err = ext4_ext_insert_extent(handle, inode, path,
+ &newex, flags);
if (err) {
+ int fb_flags = flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE ?
+ EXT4_FREE_BLOCKS_NO_QUOT_UPDATE : 0;
/* free data blocks we just allocated */
/* not a good idea to call discard here directly,
* but otherwise we'd need to call it every free() */
ext4_discard_preallocations(inode);
- ext4_free_blocks(handle, inode, 0, ext_pblock(&newex),
- ext4_ext_get_actual_len(&newex), 0);
+ ext4_free_blocks(handle, inode, NULL, ext4_ext_pblock(&newex),
+ ext4_ext_get_actual_len(&newex), fb_flags);
goto out2;
}
/* previous routine could use block we allocated */
- newblock = ext_pblock(&newex);
+ newblock = ext4_ext_pblock(&newex);
allocated = ext4_ext_get_actual_len(&newex);
if (allocated > map->m_len)
allocated = map->m_len;
* when it is _not_ an uninitialized extent.
*/
if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0) {
- ext4_ext_put_in_cache(inode, map->m_lblk, allocated, newblock,
- EXT4_EXT_CACHE_EXTENT);
+ ext4_ext_put_in_cache(inode, map->m_lblk, allocated, newblock);
ext4_update_inode_fsync_trans(handle, inode, 1);
} else
ext4_update_inode_fsync_trans(handle, inode, 0);
ext4_ext_drop_refs(path);
kfree(path);
}
- return err ? err : allocated;
+ trace_ext4_ext_map_blocks_exit(inode, map->m_lblk,
+ newblock, map->m_len, err ? err : allocated);
+
+ result = (flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) ?
+ punched_out : allocated;
+
+ return err ? err : result;
}
void ext4_ext_truncate(struct inode *inode)
handle_t *handle;
int err = 0;
+ /*
+ * finish any pending end_io work so we won't run the risk of
+ * converting any truncated blocks to initialized later
+ */
+ ext4_flush_completed_IO(inode);
+
/*
* probably first extent we're gonna free will be last in block
*/
last_block = (inode->i_size + sb->s_blocksize - 1)
>> EXT4_BLOCK_SIZE_BITS(sb);
- err = ext4_ext_remove_space(inode, last_block);
+ err = ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCKS - 1);
/* In a multi-transaction truncate, we only make the final
* transaction synchronous.
if (IS_SYNC(inode))
ext4_handle_sync(handle);
-out_stop:
up_write(&EXT4_I(inode)->i_data_sem);
+
+out_stop:
/*
* If this was a simple ftruncate() and the file will remain alive,
* then we need to clear up the orphan record which we created above.
}
/*
- * preallocate space for a file. This implements ext4's fallocate inode
+ * preallocate space for a file. This implements ext4's fallocate file
* operation, which gets called from sys_fallocate system call.
* For block-mapped files, posix_fallocate should fall back to the method
* of writing zeroes to the required new blocks (the same behavior which is
* expected for file systems which do not support fallocate() system call).
*/
-long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
+long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
{
+ struct inode *inode = file->f_path.dentry->d_inode;
handle_t *handle;
loff_t new_size;
unsigned int max_blocks;
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
return -EOPNOTSUPP;
- /* preallocation to directories is currently not supported */
- if (S_ISDIR(inode->i_mode))
- return -ENODEV;
+ /* Return error if mode is not supported */
+ if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
+ return -EOPNOTSUPP;
+ if (mode & FALLOC_FL_PUNCH_HOLE)
+ return ext4_punch_hole(file, offset, len);
+
+ trace_ext4_fallocate_enter(inode, offset, len, mode);
map.m_lblk = offset >> blkbits;
/*
* We can't just convert len to max_blocks because
ret = inode_newsize_ok(inode, (len + offset));
if (ret) {
mutex_unlock(&inode->i_mutex);
+ trace_ext4_fallocate_exit(inode, offset, max_blocks, ret);
return ret;
}
retry:
break;
}
ret = ext4_map_blocks(handle, inode, &map,
- EXT4_GET_BLOCKS_CREATE_UNINIT_EXT);
+ EXT4_GET_BLOCKS_CREATE_UNINIT_EXT |
+ EXT4_GET_BLOCKS_NO_NORMALIZE);
if (ret <= 0) {
#ifdef EXT4FS_DEBUG
WARN_ON(ret <= 0);
printk(KERN_ERR "%s: ext4_ext_map_blocks "
"returned error inode#%lu, block=%u, "
"max_blocks=%u", __func__,
- inode->i_ino, block, max_blocks);
+ inode->i_ino, map.m_lblk, max_blocks);
#endif
ext4_mark_inode_dirty(handle, inode);
ret2 = ext4_journal_stop(handle);
goto retry;
}
mutex_unlock(&inode->i_mutex);
+ trace_ext4_fallocate_exit(inode, offset, max_blocks,
+ ret > 0 ? ret2 : ret);
return ret > 0 ? ret2 : ret;
}
}
return ret > 0 ? ret2 : ret;
}
+
/*
* Callback function called for each extent to gather FIEMAP information.
*/
-static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
+static int ext4_ext_fiemap_cb(struct inode *inode, ext4_lblk_t next,
struct ext4_ext_cache *newex, struct ext4_extent *ex,
void *data)
{
- struct fiemap_extent_info *fieinfo = data;
- unsigned char blksize_bits = inode->i_sb->s_blocksize_bits;
__u64 logical;
__u64 physical;
__u64 length;
__u32 flags = 0;
- int error;
+ int ret = 0;
+ struct fiemap_extent_info *fieinfo = data;
+ unsigned char blksize_bits;
- logical = (__u64)newex->ec_block << blksize_bits;
+ blksize_bits = inode->i_sb->s_blocksize_bits;
+ logical = (__u64)newex->ec_block << blksize_bits;
- if (newex->ec_type == EXT4_EXT_CACHE_GAP) {
- pgoff_t offset;
- struct page *page;
+ if (newex->ec_start == 0) {
+ /*
+ * No extent in extent-tree contains block @newex->ec_start,
+ * then the block may stay in 1)a hole or 2)delayed-extent.
+ *
+ * Holes or delayed-extents are processed as follows.
+ * 1. lookup dirty pages with specified range in pagecache.
+ * If no page is got, then there is no delayed-extent and
+ * return with EXT_CONTINUE.
+ * 2. find the 1st mapped buffer,
+ * 3. check if the mapped buffer is both in the request range
+ * and a delayed buffer. If not, there is no delayed-extent,
+ * then return.
+ * 4. a delayed-extent is found, the extent will be collected.
+ */
+ ext4_lblk_t end = 0;
+ pgoff_t last_offset;
+ pgoff_t offset;
+ pgoff_t index;
+ pgoff_t start_index = 0;
+ struct page **pages = NULL;
struct buffer_head *bh = NULL;
+ struct buffer_head *head = NULL;
+ unsigned int nr_pages = PAGE_SIZE / sizeof(struct page *);
+
+ pages = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (pages == NULL)
+ return -ENOMEM;
offset = logical >> PAGE_SHIFT;
- page = find_get_page(inode->i_mapping, offset);
- if (!page || !page_has_buffers(page))
- return EXT_CONTINUE;
+repeat:
+ last_offset = offset;
+ head = NULL;
+ ret = find_get_pages_tag(inode->i_mapping, &offset,
+ PAGECACHE_TAG_DIRTY, nr_pages, pages);
+
+ if (!(flags & FIEMAP_EXTENT_DELALLOC)) {
+ /* First time, try to find a mapped buffer. */
+ if (ret == 0) {
+out:
+ for (index = 0; index < ret; index++)
+ page_cache_release(pages[index]);
+ /* just a hole. */
+ kfree(pages);
+ return EXT_CONTINUE;
+ }
+ index = 0;
- bh = page_buffers(page);
+next_page:
+ /* Try to find the 1st mapped buffer. */
+ end = ((__u64)pages[index]->index << PAGE_SHIFT) >>
+ blksize_bits;
+ if (!page_has_buffers(pages[index]))
+ goto out;
+ head = page_buffers(pages[index]);
+ if (!head)
+ goto out;
+
+ index++;
+ bh = head;
+ do {
+ if (end >= newex->ec_block +
+ newex->ec_len)
+ /* The buffer is out of
+ * the request range.
+ */
+ goto out;
+
+ if (buffer_mapped(bh) &&
+ end >= newex->ec_block) {
+ start_index = index - 1;
+ /* get the 1st mapped buffer. */
+ goto found_mapped_buffer;
+ }
- if (!bh)
- return EXT_CONTINUE;
+ bh = bh->b_this_page;
+ end++;
+ } while (bh != head);
- if (buffer_delay(bh)) {
- flags |= FIEMAP_EXTENT_DELALLOC;
- page_cache_release(page);
+ /* No mapped buffer in the range found in this page,
+ * We need to look up next page.
+ */
+ if (index >= ret) {
+ /* There is no page left, but we need to limit
+ * newex->ec_len.
+ */
+ newex->ec_len = end - newex->ec_block;
+ goto out;
+ }
+ goto next_page;
} else {
- page_cache_release(page);
- return EXT_CONTINUE;
+ /*Find contiguous delayed buffers. */
+ if (ret > 0 && pages[0]->index == last_offset)
+ head = page_buffers(pages[0]);
+ bh = head;
+ index = 1;
+ start_index = 0;
+ }
+
+found_mapped_buffer:
+ if (bh != NULL && buffer_delay(bh)) {
+ /* 1st or contiguous delayed buffer found. */
+ if (!(flags & FIEMAP_EXTENT_DELALLOC)) {
+ /*
+ * 1st delayed buffer found, record
+ * the start of extent.
+ */
+ flags |= FIEMAP_EXTENT_DELALLOC;
+ newex->ec_block = end;
+ logical = (__u64)end << blksize_bits;
+ }
+ /* Find contiguous delayed buffers. */
+ do {
+ if (!buffer_delay(bh))
+ goto found_delayed_extent;
+ bh = bh->b_this_page;
+ end++;
+ } while (bh != head);
+
+ for (; index < ret; index++) {
+ if (!page_has_buffers(pages[index])) {
+ bh = NULL;
+ break;
+ }
+ head = page_buffers(pages[index]);
+ if (!head) {
+ bh = NULL;
+ break;
+ }
+
+ if (pages[index]->index !=
+ pages[start_index]->index + index
+ - start_index) {
+ /* Blocks are not contiguous. */
+ bh = NULL;
+ break;
+ }
+ bh = head;
+ do {
+ if (!buffer_delay(bh))
+ /* Delayed-extent ends. */
+ goto found_delayed_extent;
+ bh = bh->b_this_page;
+ end++;
+ } while (bh != head);
+ }
+ } else if (!(flags & FIEMAP_EXTENT_DELALLOC))
+ /* a hole found. */
+ goto out;
+
+found_delayed_extent:
+ newex->ec_len = min(end - newex->ec_block,
+ (ext4_lblk_t)EXT_INIT_MAX_LEN);
+ if (ret == nr_pages && bh != NULL &&
+ newex->ec_len < EXT_INIT_MAX_LEN &&
+ buffer_delay(bh)) {
+ /* Have not collected an extent and continue. */
+ for (index = 0; index < ret; index++)
+ page_cache_release(pages[index]);
+ goto repeat;
}
+
+ for (index = 0; index < ret; index++)
+ page_cache_release(pages[index]);
+ kfree(pages);
}
physical = (__u64)newex->ec_start << blksize_bits;
if (ex && ext4_ext_is_uninitialized(ex))
flags |= FIEMAP_EXTENT_UNWRITTEN;
- /*
- * If this extent reaches EXT_MAX_BLOCK, it must be last.
- *
- * Or if ext4_ext_next_allocated_block is EXT_MAX_BLOCK,
- * this also indicates no more allocated blocks.
- *
- * XXX this might miss a single-block extent at EXT_MAX_BLOCK
- */
- if (ext4_ext_next_allocated_block(path) == EXT_MAX_BLOCK ||
- newex->ec_block + newex->ec_len - 1 == EXT_MAX_BLOCK) {
- loff_t size = i_size_read(inode);
- loff_t bs = EXT4_BLOCK_SIZE(inode->i_sb);
-
+ if (next == EXT_MAX_BLOCKS)
flags |= FIEMAP_EXTENT_LAST;
- if ((flags & FIEMAP_EXTENT_DELALLOC) &&
- logical+length > size)
- length = (size - logical + bs - 1) & ~(bs-1);
- }
- error = fiemap_fill_next_extent(fieinfo, logical, physical,
+ ret = fiemap_fill_next_extent(fieinfo, logical, physical,
length, flags);
- if (error < 0)
- return error;
- if (error == 1)
+ if (ret < 0)
+ return ret;
+ if (ret == 1)
return EXT_BREAK;
-
return EXT_CONTINUE;
}
return (error < 0 ? error : 0);
}
+/*
+ * ext4_ext_punch_hole
+ *
+ * Punches a hole of "length" bytes in a file starting
+ * at byte "offset"
+ *
+ * @inode: The inode of the file to punch a hole in
+ * @offset: The starting byte offset of the hole
+ * @length: The length of the hole
+ *
+ * Returns the number of blocks removed or negative on err
+ */
+int ext4_ext_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;
+ struct ext4_ext_cache cache_ex;
+ ext4_lblk_t first_block, last_block, num_blocks, iblock, max_blocks;
+ struct address_space *mapping = inode->i_mapping;
+ struct ext4_map_blocks map;
+ handle_t *handle;
+ loff_t first_block_offset, last_block_offset, block_len;
+ loff_t first_page, last_page, first_page_offset, last_page_offset;
+ int ret, credits, blocks_released, err = 0;
+
+ first_block = (offset + sb->s_blocksize - 1) >>
+ EXT4_BLOCK_SIZE_BITS(sb);
+ last_block = (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb);
+
+ first_block_offset = first_block << EXT4_BLOCK_SIZE_BITS(sb);
+ last_block_offset = last_block << EXT4_BLOCK_SIZE_BITS(sb);
+
+ 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;
+
+ /*
+ * 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,
+ first_page_offset == 0 ? 0 : first_page_offset-1,
+ last_page_offset);
+
+ if (err)
+ return err;
+ }
+
+ /* Now release the pages */
+ if (last_page_offset > first_page_offset) {
+ truncate_inode_pages_range(mapping, first_page_offset,
+ last_page_offset-1);
+ }
+
+ /* finish any pending end_io work */
+ ext4_flush_completed_IO(inode);
+
+ credits = ext4_writepage_trans_blocks(inode);
+ handle = ext4_journal_start(inode, credits);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ err = ext4_orphan_add(handle, inode);
+ if (err)
+ goto out;
+
+ /*
+ * Now we need to zero out the un block aligned data.
+ * If the file is smaller than a block, just
+ * zero out the middle
+ */
+ if (first_block > last_block)
+ ext4_block_zero_page_range(handle, mapping, offset, length);
+ else {
+ /* zero out the head of the hole before the first block */
+ block_len = first_block_offset - offset;
+ if (block_len > 0)
+ ext4_block_zero_page_range(handle, mapping,
+ offset, block_len);
+
+ /* zero out the tail of the hole after the last block */
+ block_len = offset + length - last_block_offset;
+ if (block_len > 0) {
+ ext4_block_zero_page_range(handle, mapping,
+ last_block_offset, block_len);
+ }
+ }
+
+ /* If there are no blocks to remove, return now */
+ if (first_block >= last_block)
+ goto out;
+
+ down_write(&EXT4_I(inode)->i_data_sem);
+ ext4_ext_invalidate_cache(inode);
+ ext4_discard_preallocations(inode);
+
+ /*
+ * Loop over all the blocks and identify blocks
+ * that need to be punched out
+ */
+ iblock = first_block;
+ blocks_released = 0;
+ while (iblock < last_block) {
+ max_blocks = last_block - iblock;
+ num_blocks = 1;
+ memset(&map, 0, sizeof(map));
+ map.m_lblk = iblock;
+ map.m_len = max_blocks;
+ ret = ext4_ext_map_blocks(handle, inode, &map,
+ EXT4_GET_BLOCKS_PUNCH_OUT_EXT);
+
+ if (ret > 0) {
+ blocks_released += ret;
+ num_blocks = ret;
+ } else if (ret == 0) {
+ /*
+ * If map blocks could not find the block,
+ * then it is in a hole. If the hole was
+ * not already cached, then map blocks should
+ * put it in the cache. So we can get the hole
+ * out of the cache
+ */
+ memset(&cache_ex, 0, sizeof(cache_ex));
+ if ((ext4_ext_check_cache(inode, iblock, &cache_ex)) &&
+ !cache_ex.ec_start) {
+
+ /* The hole is cached */
+ num_blocks = cache_ex.ec_block +
+ cache_ex.ec_len - iblock;
+
+ } else {
+ /* The block could not be identified */
+ err = -EIO;
+ break;
+ }
+ } else {
+ /* Map blocks error */
+ err = ret;
+ break;
+ }
+
+ if (num_blocks == 0) {
+ /* This condition should never happen */
+ ext_debug("Block lookup failed");
+ err = -EIO;
+ break;
+ }
+
+ iblock += num_blocks;
+ }
+
+ if (blocks_released > 0) {
+ ext4_ext_invalidate_cache(inode);
+ ext4_discard_preallocations(inode);
+ }
+
+ if (IS_SYNC(inode))
+ ext4_handle_sync(handle);
+
+ up_write(&EXT4_I(inode)->i_data_sem);
+
+out:
+ ext4_orphan_del(handle, inode);
+ inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
+ ext4_mark_inode_dirty(handle, inode);
+ ext4_journal_stop(handle);
+ return err;
+}
int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
__u64 start, __u64 len)
{
start_blk = start >> inode->i_sb->s_blocksize_bits;
last_blk = (start + len - 1) >> inode->i_sb->s_blocksize_bits;
- if (last_blk >= EXT_MAX_BLOCK)
- last_blk = EXT_MAX_BLOCK-1;
+ if (last_blk >= EXT_MAX_BLOCKS)
+ last_blk = EXT_MAX_BLOCKS-1;
len_blks = ((ext4_lblk_t) last_blk) - start_blk + 1;
/*
return error;
}
-