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Diffstat (limited to 'fs/ext4/extents.c')
-rw-r--r--fs/ext4/extents.c354
1 files changed, 284 insertions, 70 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 9ae6e67..47929c4 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -32,7 +32,6 @@
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/time.h>
-#include <linux/ext4_jbd2.h>
#include <linux/jbd2.h>
#include <linux/highuid.h>
#include <linux/pagemap.h>
@@ -40,8 +39,9 @@
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/falloc.h>
-#include <linux/ext4_fs_extents.h>
#include <asm/uaccess.h>
+#include "ext4_jbd2.h"
+#include "ext4_extents.h"
/*
@@ -308,7 +308,7 @@ corrupted:
}
#define ext4_ext_check_header(inode, eh, depth) \
- __ext4_ext_check_header(__FUNCTION__, inode, eh, depth)
+ __ext4_ext_check_header(__func__, inode, eh, depth)
#ifdef EXT_DEBUG
static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
@@ -614,7 +614,7 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
ix->ei_block = cpu_to_le32(logical);
ext4_idx_store_pblock(ix, ptr);
- curp->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(curp->p_hdr->eh_entries)+1);
+ le16_add_cpu(&curp->p_hdr->eh_entries, 1);
BUG_ON(le16_to_cpu(curp->p_hdr->eh_entries)
> le16_to_cpu(curp->p_hdr->eh_max));
@@ -736,7 +736,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
}
if (m) {
memmove(ex, path[depth].p_ext-m, sizeof(struct ext4_extent)*m);
- neh->eh_entries = cpu_to_le16(le16_to_cpu(neh->eh_entries)+m);
+ le16_add_cpu(&neh->eh_entries, m);
}
set_buffer_uptodate(bh);
@@ -753,8 +753,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
err = ext4_ext_get_access(handle, inode, path + depth);
if (err)
goto cleanup;
- path[depth].p_hdr->eh_entries =
- cpu_to_le16(le16_to_cpu(path[depth].p_hdr->eh_entries)-m);
+ le16_add_cpu(&path[depth].p_hdr->eh_entries, -m);
err = ext4_ext_dirty(handle, inode, path + depth);
if (err)
goto cleanup;
@@ -817,8 +816,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
if (m) {
memmove(++fidx, path[i].p_idx - m,
sizeof(struct ext4_extent_idx) * m);
- neh->eh_entries =
- cpu_to_le16(le16_to_cpu(neh->eh_entries) + m);
+ le16_add_cpu(&neh->eh_entries, m);
}
set_buffer_uptodate(bh);
unlock_buffer(bh);
@@ -834,7 +832,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
err = ext4_ext_get_access(handle, inode, path + i);
if (err)
goto cleanup;
- path[i].p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path[i].p_hdr->eh_entries)-m);
+ le16_add_cpu(&path[i].p_hdr->eh_entries, -m);
err = ext4_ext_dirty(handle, inode, path + i);
if (err)
goto cleanup;
@@ -1369,7 +1367,7 @@ int ext4_ext_try_to_merge(struct inode *inode,
* sizeof(struct ext4_extent);
memmove(ex + 1, ex + 2, len);
}
- eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries) - 1);
+ le16_add_cpu(&eh->eh_entries, -1);
merge_done = 1;
WARN_ON(eh->eh_entries == 0);
if (!eh->eh_entries)
@@ -1560,7 +1558,7 @@ has_space:
path[depth].p_ext = nearex;
}
- eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)+1);
+ 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));
@@ -1699,7 +1697,7 @@ static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
err = ext4_ext_get_access(handle, inode, path);
if (err)
return err;
- path->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path->p_hdr->eh_entries)-1);
+ le16_add_cpu(&path->p_hdr->eh_entries, -1);
err = ext4_ext_dirty(handle, inode, path);
if (err)
return err;
@@ -1902,7 +1900,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
if (num == 0) {
/* this extent is removed; mark slot entirely unused */
ext4_ext_store_pblock(ex, 0);
- eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1);
+ le16_add_cpu(&eh->eh_entries, -1);
}
ex->ee_block = cpu_to_le32(block);
@@ -1979,7 +1977,7 @@ static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start)
* We start scanning from right side, freeing all the blocks
* after i_size and walking into the tree depth-wise.
*/
- path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_KERNEL);
+ path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_NOFS);
if (path == NULL) {
ext4_journal_stop(handle);
return -ENOMEM;
@@ -2138,6 +2136,82 @@ void ext4_ext_release(struct super_block *sb)
#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)
+{
+ int ret = -EIO;
+ 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;
+ }
+
+ init_completion(&event);
+ bio->bi_private = &event;
+ bio->bi_end_io = bi_complete;
+ submit_bio(WRITE, bio);
+ wait_for_completion(&event);
+
+ if (test_bit(BIO_UPTODATE, &bio->bi_flags))
+ ret = 0;
+ else {
+ ret = -EIO;
+ break;
+ }
+ bio_put(bio);
+ ee_len -= done;
+ ee_pblock += done << (blkbits - 9);
+ }
+ return ret;
+}
+
+#define EXT4_EXT_ZERO_LEN 7
+
/*
* This function is called by ext4_ext_get_blocks() if someone tries to write
* to an uninitialized extent. It may result in splitting the uninitialized
@@ -2154,7 +2228,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
ext4_lblk_t iblock,
unsigned long max_blocks)
{
- struct ext4_extent *ex, newex;
+ struct ext4_extent *ex, newex, orig_ex;
struct ext4_extent *ex1 = NULL;
struct ext4_extent *ex2 = NULL;
struct ext4_extent *ex3 = NULL;
@@ -2173,10 +2247,26 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
allocated = ee_len - (iblock - ee_block);
newblock = iblock - 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));
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) {
+ 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 iblock - 1 : uninitialized */
if (iblock > ee_block) {
@@ -2195,19 +2285,103 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
/* ex3: to ee_block + ee_len : uninitialised */
if (allocated > max_blocks) {
unsigned int newdepth;
+ /* If extent has less than EXT4_EXT_ZERO_LEN zerout directly */
+ if (allocated <= EXT4_EXT_ZERO_LEN) {
+ /* 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(iblock);
+ ext4_ext_store_pblock(ex3, newblock);
+ ex3->ee_len = cpu_to_le16(allocated);
+ err = ext4_ext_insert_extent(handle, inode, path, ex3);
+ 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);
+ /* zeroed the full extent */
+ 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,
+ iblock, path);
+ if (IS_ERR(path)) {
+ err = PTR_ERR(path);
+ return err;
+ }
+ 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(iblock + max_blocks);
ext4_ext_store_pblock(ex3, newblock + max_blocks);
ex3->ee_len = cpu_to_le16(allocated - max_blocks);
ext4_ext_mark_uninitialized(ex3);
err = ext4_ext_insert_extent(handle, inode, path, ex3);
- if (err)
- goto out;
+ if (err == -ENOSPC) {
+ 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;
+
+ } 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 successfull insert of the
+ * split extent
+ */
+ orig_ex.ee_len = cpu_to_le16(ee_len -
+ ext4_ext_get_actual_len(ex3));
if (newdepth != depth) {
depth = newdepth;
ext4_ext_drop_refs(path);
@@ -2226,6 +2400,24 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
goto out;
}
allocated = max_blocks;
+
+ /* 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 &&
+ iblock != ee_block) {
+ 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;
+ }
}
/*
* If there was a change of depth as part of the
@@ -2282,8 +2474,29 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
goto out;
insert:
err = ext4_ext_insert_extent(handle, inode, path, &newex);
+ if (err == -ENOSPC) {
+ 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:
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;
}
/*
@@ -2393,8 +2606,20 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
}
if (create == EXT4_CREATE_UNINITIALIZED_EXT)
goto out;
- if (!create)
+ if (!create) {
+ /*
+ * 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.
+ */
+ if (allocated > max_blocks)
+ allocated = max_blocks;
+ /* mark the buffer unwritten */
+ __set_bit(BH_Unwritten, &bh_result->b_state);
goto out2;
+ }
ret = ext4_ext_convert_to_initialized(handle, inode,
path, iblock,
@@ -2584,6 +2809,8 @@ out_stop:
ext4_orphan_del(handle, inode);
up_write(&EXT4_I(inode)->i_data_sem);
+ inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
+ ext4_mark_inode_dirty(handle, inode);
ext4_journal_stop(handle);
}
@@ -2608,6 +2835,28 @@ int ext4_ext_writepage_trans_blocks(struct inode *inode, int num)
return needed;
}
+static void ext4_falloc_update_inode(struct inode *inode,
+ int mode, loff_t new_size, int update_ctime)
+{
+ struct timespec now;
+
+ if (update_ctime) {
+ now = current_fs_time(inode->i_sb);
+ if (!timespec_equal(&inode->i_ctime, &now))
+ inode->i_ctime = now;
+ }
+ /*
+ * Update only when preallocation was requested beyond
+ * the file size.
+ */
+ if (!(mode & FALLOC_FL_KEEP_SIZE) &&
+ new_size > i_size_read(inode)) {
+ i_size_write(inode, new_size);
+ EXT4_I(inode)->i_disksize = new_size;
+ }
+
+}
+
/*
* preallocate space for a file. This implements ext4's fallocate inode
* operation, which gets called from sys_fallocate system call.
@@ -2619,8 +2868,8 @@ long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
{
handle_t *handle;
ext4_lblk_t block;
+ loff_t new_size;
unsigned long max_blocks;
- ext4_fsblk_t nblocks = 0;
int ret = 0;
int ret2 = 0;
int retries = 0;
@@ -2639,9 +2888,12 @@ long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
return -ENODEV;
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;
-
+ - block;
/*
* credits to insert 1 extent into extent tree + buffers to be able to
* modify 1 super block, 1 block bitmap and 1 group descriptor.
@@ -2657,7 +2909,6 @@ retry:
ret = PTR_ERR(handle);
break;
}
-
ret = ext4_get_blocks_wrap(handle, inode, block,
max_blocks, &map_bh,
EXT4_CREATE_UNINITIALIZED_EXT, 0);
@@ -2673,61 +2924,24 @@ retry:
ret2 = ext4_journal_stop(handle);
break;
}
- if (ret > 0) {
- /* check wrap through sign-bit/zero here */
- if ((block + ret) < 0 || (block + ret) < block) {
- ret = -EIO;
- ext4_mark_inode_dirty(handle, inode);
- ret2 = ext4_journal_stop(handle);
- break;
- }
- if (buffer_new(&map_bh) && ((block + ret) >
- (EXT4_BLOCK_ALIGN(i_size_read(inode), blkbits)
- >> blkbits)))
- nblocks = nblocks + ret;
- }
-
- /* Update ctime if new blocks get allocated */
- if (nblocks) {
- struct timespec now;
-
- now = current_fs_time(inode->i_sb);
- if (!timespec_equal(&inode->i_ctime, &now))
- inode->i_ctime = now;
- }
+ if ((block + ret) >= (EXT4_BLOCK_ALIGN(offset + len,
+ blkbits) >> blkbits))
+ new_size = offset + len;
+ else
+ new_size = (block + ret) << blkbits;
+ ext4_falloc_update_inode(inode, mode, new_size,
+ buffer_new(&map_bh));
ext4_mark_inode_dirty(handle, inode);
ret2 = ext4_journal_stop(handle);
if (ret2)
break;
}
-
- if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+ if (ret == -ENOSPC &&
+ ext4_should_retry_alloc(inode->i_sb, &retries)) {
+ ret = 0;
goto retry;
-
- /*
- * Time to update the file size.
- * Update only when preallocation was requested beyond the file size.
- */
- if (!(mode & FALLOC_FL_KEEP_SIZE) &&
- (offset + len) > i_size_read(inode)) {
- if (ret > 0) {
- /*
- * if no error, we assume preallocation succeeded
- * completely
- */
- i_size_write(inode, offset + len);
- EXT4_I(inode)->i_disksize = i_size_read(inode);
- } else if (ret < 0 && nblocks) {
- /* Handle partial allocation scenario */
- loff_t newsize;
-
- newsize = (nblocks << blkbits) + i_size_read(inode);
- i_size_write(inode, EXT4_BLOCK_ALIGN(newsize, blkbits));
- EXT4_I(inode)->i_disksize = i_size_read(inode);
- }
}
-
mutex_unlock(&inode->i_mutex);
return ret > 0 ? ret2 : ret;
}