Commit a86c6181 authored by Alex Tomas's avatar Alex Tomas Committed by Linus Torvalds

[PATCH] ext3: add extent map support

On disk extents format:
/*
* this is extent on-disk structure
* it's used at the bottom of the tree
*/
struct ext3_extent {
__le32  ee_block;       /* first logical block extent covers */
__le16  ee_len;         /* number of blocks covered by extent */
__le16  ee_start_hi;    /* high 16 bits of physical block */
__le32  ee_start;       /* low 32 bigs of physical block */
};
Signed-off-by: default avatarAlex Tomas <alex@clusterfs.com>
Signed-off-by: default avatarDave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent c3fcc813
......@@ -5,7 +5,7 @@
obj-$(CONFIG_EXT4DEV_FS) += ext4dev.o
ext4dev-y := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o \
ioctl.o namei.o super.o symlink.o hash.o resize.o
ioctl.o namei.o super.o symlink.o hash.o resize.o extents.o
ext4dev-$(CONFIG_EXT4DEV_FS_XATTR) += xattr.o xattr_user.o xattr_trusted.o
ext4dev-$(CONFIG_EXT4DEV_FS_POSIX_ACL) += acl.o
......
......@@ -134,8 +134,7 @@ static int ext4_readdir(struct file * filp,
struct buffer_head *bh = NULL;
map_bh.b_state = 0;
err = ext4_get_blocks_handle(NULL, inode, blk, 1,
&map_bh, 0, 0);
err = ext4_get_blocks_wrap(NULL, inode, blk, 1, &map_bh, 0, 0);
if (err > 0) {
page_cache_readahead(sb->s_bdev->bd_inode->i_mapping,
&filp->f_ra,
......
/*
* Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
* Written by Alex Tomas <alex@clusterfs.com>
*
* Architecture independence:
* Copyright (c) 2005, Bull S.A.
* Written by Pierre Peiffer <pierre.peiffer@bull.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public Licens
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
*/
/*
* Extents support for EXT4
*
* TODO:
* - ext4*_error() should be used in some situations
* - analyze all BUG()/BUG_ON(), use -EIO where appropriate
* - smart tree reduction
*/
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/time.h>
#include <linux/ext4_jbd2.h>
#include <linux/jbd.h>
#include <linux/smp_lock.h>
#include <linux/highuid.h>
#include <linux/pagemap.h>
#include <linux/quotaops.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/ext4_fs_extents.h>
#include <asm/uaccess.h>
static int ext4_ext_check_header(const char *function, struct inode *inode,
struct ext4_extent_header *eh)
{
const char *error_msg = NULL;
if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
error_msg = "invalid magic";
goto corrupted;
}
if (unlikely(eh->eh_max == 0)) {
error_msg = "invalid eh_max";
goto corrupted;
}
if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) {
error_msg = "invalid eh_entries";
goto corrupted;
}
return 0;
corrupted:
ext4_error(inode->i_sb, function,
"bad header in inode #%lu: %s - magic %x, "
"entries %u, max %u, depth %u",
inode->i_ino, error_msg, le16_to_cpu(eh->eh_magic),
le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
le16_to_cpu(eh->eh_depth));
return -EIO;
}
static handle_t *ext4_ext_journal_restart(handle_t *handle, int needed)
{
int err;
if (handle->h_buffer_credits > needed)
return handle;
if (!ext4_journal_extend(handle, needed))
return handle;
err = ext4_journal_restart(handle, needed);
return handle;
}
/*
* could return:
* - EROFS
* - ENOMEM
*/
static int ext4_ext_get_access(handle_t *handle, struct inode *inode,
struct ext4_ext_path *path)
{
if (path->p_bh) {
/* path points to block */
return ext4_journal_get_write_access(handle, path->p_bh);
}
/* path points to leaf/index in inode body */
/* we use in-core data, no need to protect them */
return 0;
}
/*
* could return:
* - EROFS
* - ENOMEM
* - EIO
*/
static int ext4_ext_dirty(handle_t *handle, struct inode *inode,
struct ext4_ext_path *path)
{
int err;
if (path->p_bh) {
/* path points to block */
err = ext4_journal_dirty_metadata(handle, path->p_bh);
} else {
/* path points to leaf/index in inode body */
err = ext4_mark_inode_dirty(handle, inode);
}
return err;
}
static int ext4_ext_find_goal(struct inode *inode,
struct ext4_ext_path *path,
unsigned long block)
{
struct ext4_inode_info *ei = EXT4_I(inode);
unsigned long bg_start;
unsigned long colour;
int depth;
if (path) {
struct ext4_extent *ex;
depth = path->p_depth;
/* try to predict block placement */
if ((ex = path[depth].p_ext))
return le32_to_cpu(ex->ee_start)
+ (block - le32_to_cpu(ex->ee_block));
/* it looks index is empty
* try to find starting from index itself */
if (path[depth].p_bh)
return path[depth].p_bh->b_blocknr;
}
/* OK. use inode's group */
bg_start = (ei->i_block_group * EXT4_BLOCKS_PER_GROUP(inode->i_sb)) +
le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_first_data_block);
colour = (current->pid % 16) *
(EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
return bg_start + colour + block;
}
static int
ext4_ext_new_block(handle_t *handle, struct inode *inode,
struct ext4_ext_path *path,
struct ext4_extent *ex, int *err)
{
int goal, newblock;
goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
newblock = ext4_new_block(handle, inode, goal, err);
return newblock;
}
static inline int ext4_ext_space_block(struct inode *inode)
{
int size;
size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
/ sizeof(struct ext4_extent);
#ifdef AGRESSIVE_TEST
if (size > 6)
size = 6;
#endif
return size;
}
static inline int ext4_ext_space_block_idx(struct inode *inode)
{
int size;
size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
/ sizeof(struct ext4_extent_idx);
#ifdef AGRESSIVE_TEST
if (size > 5)
size = 5;
#endif
return size;
}
static inline int ext4_ext_space_root(struct inode *inode)
{
int size;
size = sizeof(EXT4_I(inode)->i_data);
size -= sizeof(struct ext4_extent_header);
size /= sizeof(struct ext4_extent);
#ifdef AGRESSIVE_TEST
if (size > 3)
size = 3;
#endif
return size;
}
static inline int ext4_ext_space_root_idx(struct inode *inode)
{
int size;
size = sizeof(EXT4_I(inode)->i_data);
size -= sizeof(struct ext4_extent_header);
size /= sizeof(struct ext4_extent_idx);
#ifdef AGRESSIVE_TEST
if (size > 4)
size = 4;
#endif
return size;
}
#ifdef EXT_DEBUG
static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
{
int k, l = path->p_depth;
ext_debug("path:");
for (k = 0; k <= l; k++, path++) {
if (path->p_idx) {
ext_debug(" %d->%d", le32_to_cpu(path->p_idx->ei_block),
le32_to_cpu(path->p_idx->ei_leaf));
} else if (path->p_ext) {
ext_debug(" %d:%d:%d",
le32_to_cpu(path->p_ext->ee_block),
le16_to_cpu(path->p_ext->ee_len),
le32_to_cpu(path->p_ext->ee_start));
} else
ext_debug(" []");
}
ext_debug("\n");
}
static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
{
int depth = ext_depth(inode);
struct ext4_extent_header *eh;
struct ext4_extent *ex;
int i;
if (!path)
return;
eh = path[depth].p_hdr;
ex = EXT_FIRST_EXTENT(eh);
for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
ext_debug("%d:%d:%d ", le32_to_cpu(ex->ee_block),
le16_to_cpu(ex->ee_len),
le32_to_cpu(ex->ee_start));
}
ext_debug("\n");
}
#else
#define ext4_ext_show_path(inode,path)
#define ext4_ext_show_leaf(inode,path)
#endif
static void ext4_ext_drop_refs(struct ext4_ext_path *path)
{
int depth = path->p_depth;
int i;
for (i = 0; i <= depth; i++, path++)
if (path->p_bh) {
brelse(path->p_bh);
path->p_bh = NULL;
}
}
/*
* binary search for closest index by given block
*/
static void
ext4_ext_binsearch_idx(struct inode *inode, struct ext4_ext_path *path, int block)
{
struct ext4_extent_header *eh = path->p_hdr;
struct ext4_extent_idx *r, *l, *m;
BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
BUG_ON(le16_to_cpu(eh->eh_entries) <= 0);
ext_debug("binsearch for %d(idx): ", block);
l = EXT_FIRST_INDEX(eh) + 1;
r = EXT_FIRST_INDEX(eh) + le16_to_cpu(eh->eh_entries) - 1;
while (l <= r) {
m = l + (r - l) / 2;
if (block < le32_to_cpu(m->ei_block))
r = m - 1;
else
l = m + 1;
ext_debug("%p(%u):%p(%u):%p(%u) ", l, l->ei_block,
m, m->ei_block, r, r->ei_block);
}
path->p_idx = l - 1;
ext_debug(" -> %d->%d ", le32_to_cpu(path->p_idx->ei_block),
le32_to_cpu(path->p_idx->ei_leaf));
#ifdef CHECK_BINSEARCH
{
struct ext4_extent_idx *chix, *ix;
int k;
chix = ix = EXT_FIRST_INDEX(eh);
for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) {
if (k != 0 &&
le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) {
printk("k=%d, ix=0x%p, first=0x%p\n", k,
ix, EXT_FIRST_INDEX(eh));
printk("%u <= %u\n",
le32_to_cpu(ix->ei_block),
le32_to_cpu(ix[-1].ei_block));
}
BUG_ON(k && le32_to_cpu(ix->ei_block)
<= le32_to_cpu(ix[-1].ei_block));
if (block < le32_to_cpu(ix->ei_block))
break;
chix = ix;
}
BUG_ON(chix != path->p_idx);
}
#endif
}
/*
* binary search for closest extent by given block
*/
static void
ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block)
{
struct ext4_extent_header *eh = path->p_hdr;
struct ext4_extent *r, *l, *m;
BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
if (eh->eh_entries == 0) {
/*
* this leaf is empty yet:
* we get such a leaf in split/add case
*/
return;
}
ext_debug("binsearch for %d: ", block);
l = EXT_FIRST_EXTENT(eh) + 1;
r = EXT_FIRST_EXTENT(eh) + le16_to_cpu(eh->eh_entries) - 1;
while (l <= r) {
m = l + (r - l) / 2;
if (block < le32_to_cpu(m->ee_block))
r = m - 1;
else
l = m + 1;
ext_debug("%p(%u):%p(%u):%p(%u) ", l, l->ee_block,
m, m->ee_block, r, r->ee_block);
}
path->p_ext = l - 1;
ext_debug(" -> %d:%d:%d ",
le32_to_cpu(path->p_ext->ee_block),
le32_to_cpu(path->p_ext->ee_start),
le16_to_cpu(path->p_ext->ee_len));
#ifdef CHECK_BINSEARCH
{
struct ext4_extent *chex, *ex;
int k;
chex = ex = EXT_FIRST_EXTENT(eh);
for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) {
BUG_ON(k && le32_to_cpu(ex->ee_block)
<= le32_to_cpu(ex[-1].ee_block));
if (block < le32_to_cpu(ex->ee_block))
break;
chex = ex;
}
BUG_ON(chex != path->p_ext);
}
#endif
}
int ext4_ext_tree_init(handle_t *handle, struct inode *inode)
{
struct ext4_extent_header *eh;
eh = ext_inode_hdr(inode);
eh->eh_depth = 0;
eh->eh_entries = 0;
eh->eh_magic = EXT4_EXT_MAGIC;
eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode));
ext4_mark_inode_dirty(handle, inode);
ext4_ext_invalidate_cache(inode);
return 0;
}
struct ext4_ext_path *
ext4_ext_find_extent(struct inode *inode, int block, struct ext4_ext_path *path)
{
struct ext4_extent_header *eh;
struct buffer_head *bh;
short int depth, i, ppos = 0, alloc = 0;
eh = ext_inode_hdr(inode);
BUG_ON(eh == NULL);
if (ext4_ext_check_header(__FUNCTION__, inode, eh))
return ERR_PTR(-EIO);
i = depth = ext_depth(inode);
/* account possible depth increase */
if (!path) {
path = kmalloc(sizeof(struct ext4_ext_path) * (depth + 2),
GFP_NOFS);
if (!path)
return ERR_PTR(-ENOMEM);
alloc = 1;
}
memset(path, 0, sizeof(struct ext4_ext_path) * (depth + 1));
path[0].p_hdr = eh;
/* walk through the tree */
while (i) {
ext_debug("depth %d: num %d, max %d\n",
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 = le32_to_cpu(path[ppos].p_idx->ei_leaf);
path[ppos].p_depth = i;
path[ppos].p_ext = NULL;
bh = sb_bread(inode->i_sb, path[ppos].p_block);
if (!bh)
goto err;
eh = ext_block_hdr(bh);
ppos++;
BUG_ON(ppos > depth);
path[ppos].p_bh = bh;
path[ppos].p_hdr = eh;
i--;
if (ext4_ext_check_header(__FUNCTION__, inode, eh))
goto err;
}
path[ppos].p_depth = i;
path[ppos].p_hdr = eh;
path[ppos].p_ext = NULL;
path[ppos].p_idx = NULL;
if (ext4_ext_check_header(__FUNCTION__, inode, eh))
goto err;
/* find extent */
ext4_ext_binsearch(inode, path + ppos, block);
ext4_ext_show_path(inode, path);
return path;
err:
ext4_ext_drop_refs(path);
if (alloc)
kfree(path);
return ERR_PTR(-EIO);
}
/*
* insert new index [logical;ptr] into the block at cupr
* it check where to insert: before curp or after curp
*/
static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
struct ext4_ext_path *curp,
int logical, int ptr)
{
struct ext4_extent_idx *ix;
int len, err;
if ((err = ext4_ext_get_access(handle, inode, curp)))
return err;
BUG_ON(logical == le32_to_cpu(curp->p_idx->ei_block));
len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx;
if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
/* insert after */
if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) {
len = (len - 1) * sizeof(struct ext4_extent_idx);
len = len < 0 ? 0 : len;
ext_debug("insert new index %d after: %d. "
"move %d from 0x%p to 0x%p\n",
logical, ptr, len,
(curp->p_idx + 1), (curp->p_idx + 2));
memmove(curp->p_idx + 2, curp->p_idx + 1, len);
}
ix = curp->p_idx + 1;
} else {
/* insert before */
len = len * sizeof(struct ext4_extent_idx);
len = len < 0 ? 0 : len;
ext_debug("insert new index %d before: %d. "
"move %d from 0x%p to 0x%p\n",
logical, ptr, len,
curp->p_idx, (curp->p_idx + 1));
memmove(curp->p_idx + 1, curp->p_idx, len);
ix = curp->p_idx;
}
ix->ei_block = cpu_to_le32(logical);
ix->ei_leaf = cpu_to_le32(ptr);
curp->p_hdr->eh_entries = cpu_to_le16(le16_to_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));
BUG_ON(ix > EXT_LAST_INDEX(curp->p_hdr));
err = ext4_ext_dirty(handle, inode, curp);
ext4_std_error(inode->i_sb, err);
return err;
}
/*
* routine inserts new subtree into the path, using free index entry
* at depth 'at:
* - allocates all needed blocks (new leaf and all intermediate index blocks)
* - makes decision where to split
* - moves remaining extens and index entries (right to the split point)
* into the newly allocated blocks
* - initialize subtree
*/
static int ext4_ext_split(handle_t *handle, struct inode *inode,
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;
unsigned long newblock, oldblock;
__le32 border;
int *ablocks = NULL; /* array of allocated blocks */
int err = 0;
/* make decision: where to split? */
/* FIXME: now desicion is simplest: at current extent */
/* if current leaf will be splitted, then we should use
* border from split point */
BUG_ON(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr));
if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
border = path[depth].p_ext[1].ee_block;
ext_debug("leaf will be splitted."
" next leaf starts at %d\n",
le32_to_cpu(border));
} else {
border = newext->ee_block;
ext_debug("leaf will be added."
" next leaf starts at %d\n",
le32_to_cpu(border));
}
/*
* if error occurs, then we break processing
* and turn filesystem read-only. so, index won't
* be inserted and tree will be in consistent
* state. next mount will repair buffers too
*/
/*
* get array to track all allocated blocks
* we need this to handle errors and free blocks
* upon them
*/
ablocks = kmalloc(sizeof(unsigned long) * depth, GFP_NOFS);
if (!ablocks)
return -ENOMEM;
memset(ablocks, 0, sizeof(unsigned long) * depth);
/* allocate all needed blocks */
ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
for (a = 0; a < depth - at; a++) {
newblock = ext4_ext_new_block(handle, inode, path, newext, &err);
if (newblock == 0)
goto cleanup;
ablocks[a] = newblock;
}
/* initialize new leaf */
newblock = ablocks[--a];
BUG_ON(newblock == 0);
bh = sb_getblk(inode->i_sb, newblock);
if (!bh) {
err = -EIO;
goto cleanup;
}
lock_buffer(bh);
if ((err = ext4_journal_get_create_access(handle, bh)))
goto cleanup;
neh = ext_block_hdr(bh);
neh->eh_entries = 0;
neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode));
neh->eh_magic = EXT4_EXT_MAGIC;
neh->eh_depth = 0;
ex = EXT_FIRST_EXTENT(neh);
/* move remain of path[depth] to the new leaf */
BUG_ON(path[depth].p_hdr->eh_entries != path[depth].p_hdr->eh_max);
/* 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:%d:%d in new leaf %lu\n",
le32_to_cpu(path[depth].p_ext->ee_block),
le32_to_cpu(path[depth].p_ext->ee_start),
le16_to_cpu(path[depth].p_ext->ee_len),
newblock);
/*memmove(ex++, path[depth].p_ext++,
sizeof(struct ext4_extent));
neh->eh_entries++;*/
path[depth].p_ext++;
m++;
}
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);
}
set_buffer_uptodate(bh);
unlock_buffer(bh);
if ((err = ext4_journal_dirty_metadata(handle, bh)))
goto cleanup;
brelse(bh);
bh = NULL;
/* correct old leaf */
if (m) {
if ((err = ext4_ext_get_access(handle, inode, path + depth)))
goto cleanup;
path[depth].p_hdr->eh_entries =
cpu_to_le16(le16_to_cpu(path[depth].p_hdr->eh_entries)-m);
if ((err = ext4_ext_dirty(handle, inode, path + depth)))
goto cleanup;
}
/* create intermediate indexes */
k = depth - at - 1;
BUG_ON(k < 0);
if (k)
ext_debug("create %d intermediate indices\n", k);
/* insert new index into current index block */
/* current depth stored in i var */
i = depth - 1;
while (k--) {
oldblock = newblock;
newblock = ablocks[--a];
bh = sb_getblk(inode->i_sb, newblock);
if (!bh) {
err = -EIO;
goto cleanup;
}
lock_buffer(bh);
if ((err = ext4_journal_get_create_access(handle, bh)))
goto cleanup;
neh = ext_block_hdr(bh);
neh->eh_entries = cpu_to_le16(1);
neh->eh_magic = EXT4_EXT_MAGIC;
neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode));
neh->eh_depth = cpu_to_le16(depth - i);
fidx = EXT_FIRST_INDEX(neh);
fidx->ei_block = border;
fidx->ei_leaf = cpu_to_le32(oldblock);
ext_debug("int.index at %d (block %lu): %lu -> %lu\n", i,
newblock, (unsigned long) 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));
BUG_ON(EXT_MAX_INDEX(path[i].p_hdr) !=
EXT_LAST_INDEX(path[i].p_hdr));
while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
ext_debug("%d: move %d:%d in new index %lu\n", i,
le32_to_cpu(path[i].p_idx->ei_block),
le32_to_cpu(path[i].p_idx->ei_leaf),
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++;
}
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);
}
set_buffer_uptodate(bh);
unlock_buffer(bh);
if ((err = ext4_journal_dirty_metadata(handle, bh)))
goto cleanup;
brelse(bh);
bh = NULL;
/* correct old index */
if (m) {
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);
err = ext4_ext_dirty(handle, inode, path + i);
if (err)
goto cleanup;
}
i--;
}
/* insert new index */
if (err)
goto cleanup;
err = ext4_ext_insert_index(handle, inode, path + at,
le32_to_cpu(border), newblock);
cleanup:
if (bh) {
if (buffer_locked(bh))
unlock_buffer(bh);
brelse(bh);
}
if (err) {
/* free all allocated blocks in error case */
for (i = 0; i < depth; i++) {
if (!ablocks[i])
continue;
ext4_free_blocks(handle, inode, ablocks[i], 1);
}
}
kfree(ablocks);
return err;
}
/*
* routine implements tree growing procedure:
* - allocates new block
* - moves top-level data (index block or leaf) into the new block
* - initialize new top-level, creating index that points to the
* just created block
*/
static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
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;
unsigned long newblock;
int err = 0;
newblock = ext4_ext_new_block(handle, inode, path, newext, &err);
if (newblock == 0)
return err;
bh = sb_getblk(inode->i_sb, newblock);
if (!bh) {
err = -EIO;
ext4_std_error(inode->i_sb, err);
return err;
}
lock_buffer(bh);
if ((err = ext4_journal_get_create_access(handle, bh))) {
unlock_buffer(bh);
goto out;
}
/* move top-level index/leaf into new block */
memmove(bh->b_data, curp->p_hdr, sizeof(EXT4_I(inode)->i_data));
/* set size of new block */
neh = ext_block_hdr(bh);
/* old root could have indexes or leaves
* so calculate e_max right way */
if (ext_depth(inode))
neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode));
else
neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode));
neh->eh_magic = EXT4_EXT_MAGIC;
set_buffer_uptodate(bh);
unlock_buffer(bh);
if ((err = ext4_journal_dirty_metadata(handle, bh)))
goto out;
/* create index in new top-level index: num,max,pointer */
if ((err = ext4_ext_get_access(handle, inode, curp)))
goto out;
curp->p_hdr->eh_magic = EXT4_EXT_MAGIC;
curp->p_hdr->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode));
curp->p_hdr->eh_entries = cpu_to_le16(1);
curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr);
/* FIXME: it works, but actually path[0] can be index */
curp->p_idx->ei_block = EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block;
curp->p_idx->ei_leaf = cpu_to_le32(newblock);
neh = ext_inode_hdr(inode);
fidx = EXT_FIRST_INDEX(neh);
ext_debug("new root: num %d(%d), lblock %d, ptr %d\n",
le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max),
le32_to_cpu(fidx->ei_block), le32_to_cpu(fidx->ei_leaf));
neh->eh_depth = cpu_to_le16(path->p_depth + 1);
err = ext4_ext_dirty(handle, inode, curp);
out:
brelse(bh);
return err;
}
/*
* routine finds empty index and adds new leaf. if no free index 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)
{
struct ext4_ext_path *curp;
int depth, i, err = 0;
repeat:
i = depth = ext_depth(inode);
/* walk up to the tree and look for free index entry */
curp = path + depth;
while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
i--;
curp--;
}
/* we use already allocated block for index block
* so, subsequent data blocks should be contigoues */
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);
/* refill path */
ext4_ext_drop_refs(path);
path = ext4_ext_find_extent(inode,
le32_to_cpu(newext->ee_block),
path);
if (IS_ERR(path))
err = PTR_ERR(path);
} else {
/* tree is full, time to grow in depth */
err = ext4_ext_grow_indepth(handle, inode, path, newext);
if (err)
goto out;
/* refill path */
ext4_ext_drop_refs(path);
path = ext4_ext_find_extent(inode,
le32_to_cpu(newext->ee_block),
path);
if (IS_ERR(path)) {
err = PTR_ERR(path);
goto out;
}
/*
* only first (depth 0 -> 1) produces free space
* in all other cases we have to split growed tree
*/
depth = ext_depth(inode);
if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
/* now we need split */
goto repeat;
}
}
out:
return err;
}
/*
* returns allocated block in subsequent extent or EXT_MAX_BLOCK
* NOTE: it consider block number from index entry as
* allocated block. thus, index entries have to be consistent
* with leafs
*/
static unsigned long
ext4_ext_next_allocated_block(struct ext4_ext_path *path)
{
int depth;
BUG_ON(path == NULL);
depth = path->p_depth;
if (depth == 0 && path->p_ext == NULL)
return EXT_MAX_BLOCK;
while (depth >= 0) {
if (depth == path->p_depth) {
/* leaf */
if (path[depth].p_ext !=
EXT_LAST_EXTENT(path[depth].p_hdr))
return le32_to_cpu(path[depth].p_ext[1].ee_block);
} else {
/* index */
if (path[depth].p_idx !=
EXT_LAST_INDEX(path[depth].p_hdr))
return le32_to_cpu(path[depth].p_idx[1].ei_block);
}
depth--;
}
return EXT_MAX_BLOCK;
}
/*
* returns first allocated block from next leaf or EXT_MAX_BLOCK
*/
static unsigned ext4_ext_next_leaf_block(struct inode *inode,
struct ext4_ext_path *path)
{
int depth;
BUG_ON(path == NULL);
depth = path->p_depth;
/* zero-tree has no leaf blocks at all */
if (depth == 0)
return EXT_MAX_BLOCK;
/* go to index block */
depth--;
while (depth >= 0) {
if (path[depth].p_idx !=
EXT_LAST_INDEX(path[depth].p_hdr))
return le32_to_cpu(path[depth].p_idx[1].ei_block);
depth--;
}
return EXT_MAX_BLOCK;
}
/*
* if leaf gets modified and modified extent is first in the leaf
* then we have to correct all indexes above
* TODO: do we need to correct tree in all cases?
*/
int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
struct ext4_ext_path *path)
{
struct ext4_extent_header *eh;
int depth = ext_depth(inode);
struct ext4_extent *ex;
__le32 border;
int k, err = 0;
eh = path[depth].p_hdr;
ex = path[depth].p_ext;
BUG_ON(ex == NULL);
BUG_ON(eh == NULL);
if (depth == 0) {
/* there is no tree at all */
return 0;
}
if (ex != EXT_FIRST_EXTENT(eh)) {
/* we correct tree if first leaf got modified only */
return 0;
}
/*
* TODO: we need correction if border is smaller then current one
*/
k = depth - 1;
border = path[depth].p_ext->ee_block;
if ((err = ext4_ext_get_access(handle, inode, path + k)))
return err;
path[k].p_idx->ei_block = border;
if ((err = ext4_ext_dirty(handle, inode, path + k)))
return err;
while (k--) {
/* change all left-side indexes */
if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
break;
if ((err = ext4_ext_get_access(handle, inode, path + k)))
break;
path[k].p_idx->ei_block = border;
if ((err = ext4_ext_dirty(handle, inode, path + k)))
break;
}
return err;
}
static int inline
ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
struct ext4_extent *ex2)
{
/* FIXME: 48bit support */
if (le32_to_cpu(ex1->ee_block) + le16_to_cpu(ex1->ee_len)
!= le32_to_cpu(ex2->ee_block))
return 0;
#ifdef AGRESSIVE_TEST
if (le16_to_cpu(ex1->ee_len) >= 4)
return 0;
#endif
if (le32_to_cpu(ex1->ee_start) + le16_to_cpu(ex1->ee_len)
== le32_to_cpu(ex2->ee_start))
return 1;
return 0;
}
/*
* this routine tries to merge requsted extent into the existing
* extent or inserts requested extent as new one into the tree,
* creating new leaf in no-space case
*/
int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
struct ext4_ext_path *path,
struct ext4_extent *newext)
{
struct ext4_extent_header * eh;
struct ext4_extent *ex, *fex;
struct ext4_extent *nearex; /* nearest extent */
struct ext4_ext_path *npath = NULL;
int depth, len, err, next;
BUG_ON(newext->ee_len == 0);
depth = ext_depth(inode);
ex = path[depth].p_ext;
BUG_ON(path[depth].p_hdr == NULL);
/* try to insert block into found extent and return */
if (ex && ext4_can_extents_be_merged(inode, ex, newext)) {
ext_debug("append %d block to %d:%d (from %d)\n",
le16_to_cpu(newext->ee_len),
le32_to_cpu(ex->ee_block),
le16_to_cpu(ex->ee_len),
le32_to_cpu(ex->ee_start));
if ((err = ext4_ext_get_access(handle, inode, path + depth)))
return err;
ex->ee_len = cpu_to_le16(le16_to_cpu(ex->ee_len)
+ le16_to_cpu(newext->ee_len));
eh = path[depth].p_hdr;
nearex = ex;
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))
goto has_space;
/* 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) {
ext_debug("next leaf block - %d\n", next);
BUG_ON(npath != NULL);
npath = ext4_ext_find_extent(inode, next, NULL);
if (IS_ERR(npath))
return PTR_ERR(npath);
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",
le16_to_cpu(eh->eh_entries));
path = npath;
goto repeat;
}
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 found leaf
* we're gonna add new leaf in the tree
*/
err = ext4_ext_create_new_leaf(handle, inode, path, newext);
if (err)
goto cleanup;
depth = ext_depth(inode);
eh = path[depth].p_hdr;
has_space:
nearex = path[depth].p_ext;
if ((err = ext4_ext_get_access(handle, inode, path + depth)))
goto cleanup;
if (!nearex) {
/* there is no extent in this leaf, create first one */
ext_debug("first extent in the leaf: %d:%d:%d\n",
le32_to_cpu(newext->ee_block),
le32_to_cpu(newext->ee_start),
le16_to_cpu(newext->ee_len));
path[depth].p_ext = EXT_FIRST_EXTENT(eh);
} else if (le32_to_cpu(newext->ee_block)
> le32_to_cpu(nearex->ee_block)) {
/* BUG_ON(newext->ee_block == nearex->ee_block); */
if (nearex != EXT_LAST_EXTENT(eh)) {
len = EXT_MAX_EXTENT(eh) - nearex;
len = (len - 1) * sizeof(struct ext4_extent);
len = len < 0 ? 0 : len;
ext_debug("insert %d:%d:%d after: nearest 0x%p, "
"move %d from 0x%p to 0x%p\n",
le32_to_cpu(newext->ee_block),
le32_to_cpu(newext->ee_start),
le16_to_cpu(newext->ee_len),
nearex, len, nearex + 1, nearex + 2);
memmove(nearex + 2, nearex + 1, len);
}
path[depth].p_ext = nearex + 1;
} else {
BUG_ON(newext->ee_block == nearex->ee_block);
len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext4_extent);
len = len < 0 ? 0 : len;
ext_debug("insert %d:%d:%d before: nearest 0x%p, "
"move %d from 0x%p to 0x%p\n",
le32_to_cpu(newext->ee_block),
le32_to_cpu(newext->ee_start),
le16_to_cpu(newext->ee_len),
nearex, len, nearex + 1, nearex + 2);
memmove(nearex + 1, nearex, len);
path[depth].p_ext = nearex;
}
eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)+1);
nearex = path[depth].p_ext;
nearex->ee_block = newext->ee_block;
nearex->ee_start = newext->ee_start;
nearex->ee_len = newext->ee_len;
/* FIXME: support for large fs */
nearex->ee_start_hi = 0;
merge:
/* try to merge extents to the right */
while (nearex < EXT_LAST_EXTENT(eh)) {
if (!ext4_can_extents_be_merged(inode, nearex, nearex + 1))
break;
/* merge with next extent! */
nearex->ee_len = cpu_to_le16(le16_to_cpu(nearex->ee_len)
+ le16_to_cpu(nearex[1].ee_len));
if (nearex + 1 < EXT_LAST_EXTENT(eh)) {
len = (EXT_LAST_EXTENT(eh) - nearex - 1)
* sizeof(struct ext4_extent);
memmove(nearex + 1, nearex + 2, len);
}
eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1);
BUG_ON(eh->eh_entries == 0);
}
/* try to merge extents to the left */
/* time to correct all indexes above */
err = ext4_ext_correct_indexes(handle, inode, path);
if (err)
goto cleanup;
err = ext4_ext_dirty(handle, inode, path + depth);
cleanup:
if (npath) {
ext4_ext_drop_refs(npath);
kfree(npath);
}
ext4_ext_tree_changed(inode);
ext4_ext_invalidate_cache(inode);
return err;
}
int ext4_ext_walk_space(struct inode *inode, unsigned long block,
unsigned long num, ext_prepare_callback func,
void *cbdata)
{
struct ext4_ext_path *path = NULL;
struct ext4_ext_cache cbex;
struct ext4_extent *ex;
unsigned long next, start = 0, end = 0;
unsigned long last = block + num;
int depth, exists, err = 0;
BUG_ON(func == NULL);
BUG_ON(inode == NULL);
while (block < last && block != EXT_MAX_BLOCK) {
num = last - block;
/* find extent for this block */
path = ext4_ext_find_extent(inode, block, path);
if (IS_ERR(path)) {
err = PTR_ERR(path);
path = NULL;
break;
}
depth = ext_depth(inode);
BUG_ON(path[depth].p_hdr == NULL);
ex = path[depth].p_ext;
next = ext4_ext_next_allocated_block(path);
exists = 0;
if (!ex) {
/* there is no extent yet, so try to allocate
* all requested space */
start = block;
end = block + num;
} else if (le32_to_cpu(ex->ee_block) > block) {
/* need to allocate space before found extent */
start = block;
end = le32_to_cpu(ex->ee_block);
if (block + num < end)
end = block + num;
} else if (block >=
le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len)) {
/* need to allocate space after found extent */
start = block;
end = block + num;
if (end >= next)
end = next;
} else if (block >= le32_to_cpu(ex->ee_block)) {
/*
* some part of requested space is covered
* by found extent
*/
start = block;
end = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len);
if (block + num < end)
end = block + num;
exists = 1;
} else {
BUG();
}
BUG_ON(end <= start);
if (!exists) {
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 = le16_to_cpu(ex->ee_len);
cbex.ec_start = le32_to_cpu(ex->ee_start);
cbex.ec_type = EXT4_EXT_CACHE_EXTENT;
}
BUG_ON(cbex.ec_len == 0);
err = func(inode, path, &cbex, cbdata);
ext4_ext_drop_refs(path);
if (err < 0)
break;
if (err == EXT_REPEAT)
continue;
else if (err == EXT_BREAK) {
err = 0;
break;
}
if (ext_depth(inode) != depth) {
/* depth was changed. we have to realloc path */
kfree(path);
path = NULL;
}
block = cbex.ec_block + cbex.ec_len;
}
if (path) {
ext4_ext_drop_refs(path);
kfree(path);
}
return err;
}
static inline void
ext4_ext_put_in_cache(struct inode *inode, __u32 block,
__u32 len, __u32 start, int type)
{
struct ext4_ext_cache *cex;
BUG_ON(len == 0);
cex = &EXT4_I(inode)->i_cached_extent;
cex->ec_type = type;
cex->ec_block = block;
cex->ec_len = len;
cex->ec_start = start;
}
/*
* this routine calculate boundaries of the gap requested block fits into
* and cache this gap
*/
static inline void
ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
unsigned long block)
{
int depth = ext_depth(inode);
unsigned long lblock, len;
struct ext4_extent *ex;
ex = path[depth].p_ext;
if (ex == NULL) {
/* there is no extent yet, so gap is [0;-] */
lblock = 0;
len = EXT_MAX_BLOCK;
ext_debug("cache gap(whole file):");
} else if (block < le32_to_cpu(ex->ee_block)) {
lblock = block;
len = le32_to_cpu(ex->ee_block) - block;
ext_debug("cache gap(before): %lu [%lu:%lu]",
(unsigned long) block,
(unsigned long) le32_to_cpu(ex->ee_block),
(unsigned long) le16_to_cpu(ex->ee_len));
} else if (block >= le32_to_cpu(ex->ee_block)
+ le16_to_cpu(ex->ee_len)) {
lblock = le32_to_cpu(ex->ee_block)
+ le16_to_cpu(ex->ee_len);
len = ext4_ext_next_allocated_block(path);
ext_debug("cache gap(after): [%lu:%lu] %lu",
(unsigned long) le32_to_cpu(ex->ee_block),
(unsigned long) le16_to_cpu(ex->ee_len),
(unsigned long) block);
BUG_ON(len == lblock);
len = len - lblock;
} else {
lblock = len = 0;
BUG();
}
ext_debug(" -> %lu:%lu\n", (unsigned long) lblock, len);
ext4_ext_put_in_cache(inode, lblock, len, 0, EXT4_EXT_CACHE_GAP);
}
static inline int
ext4_ext_in_cache(struct inode *inode, unsigned long block,
struct ext4_extent *ex)
{
struct ext4_ext_cache *cex;
cex = &EXT4_I(inode)->i_cached_extent;
/* has cache valid data? */
if (cex->ec_type == EXT4_EXT_CACHE_NO)
return EXT4_EXT_CACHE_NO;
BUG_ON(cex->ec_type != EXT4_EXT_CACHE_GAP &&
cex->ec_type != EXT4_EXT_CACHE_EXTENT);
if (block >= cex->ec_block && block < cex->ec_block + cex->ec_len) {
ex->ee_block = cpu_to_le32(cex->ec_block);
ex->ee_start = cpu_to_le32(cex->ec_start);
ex->ee_len = cpu_to_le16(cex->ec_len);
ext_debug("%lu cached by %lu:%lu:%lu\n",
(unsigned long) block,
(unsigned long) cex->ec_block,
(unsigned long) cex->ec_len,
(unsigned long) cex->ec_start);
return cex->ec_type;
}
/* not in cache */
return EXT4_EXT_CACHE_NO;
}
/*
* routine removes index from the index block
* it's used in truncate case only. thus all requests are for
* last index in the block only
*/
int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
struct ext4_ext_path *path)
{
struct buffer_head *bh;
int err;
unsigned long leaf;
/* free index block */
path--;
leaf = le32_to_cpu(path->p_idx->ei_leaf);
BUG_ON(path->p_hdr->eh_entries == 0);
if ((err = ext4_ext_get_access(handle, inode, path)))
return err;
path->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path->p_hdr->eh_entries)-1);
if ((err = ext4_ext_dirty(handle, inode, path)))
return err;
ext_debug("index is empty, remove it, free block %lu\n", leaf);
bh = sb_find_get_block(inode->i_sb, leaf);
ext4_forget(handle, 1, inode, bh, leaf);
ext4_free_blocks(handle, inode, leaf, 1);
return err;
}
/*
* This routine returns max. credits extent tree can consume.
* It should be OK for low-performance paths like ->writepage()
* To allow many writing process to fit a single transaction,
* caller should calculate credits under truncate_mutex and
* pass actual path.
*/
int inline ext4_ext_calc_credits_for_insert(struct inode *inode,
struct ext4_ext_path *path)
{
int depth, needed;
if (path) {
/* probably there is space in leaf? */
depth = ext_depth(inode);
if (le16_to_cpu(path[depth].p_hdr->eh_entries)
< le16_to_cpu(path[depth].p_hdr->eh_max))
return 1;
}
/*
* given 32bit logical block (4294967296 blocks), max. tree
* can be 4 levels in depth -- 4 * 340^4 == 53453440000.
* let's also add one more level for imbalance.
*/
depth = 5;
/* allocation of new data block(s) */
needed = 2;
/*
* tree can be full, so it'd need to grow in depth:
* allocation + old root + new root
*/
needed += 2 + 1 + 1;
/*
* Index split can happen, we'd need:
* allocate intermediate indexes (bitmap + group)
* + change two blocks at each level, but root (already included)
*/
needed = (depth * 2) + (depth * 2);
/* any allocation modifies superblock */
needed += 1;
return needed;
}
static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
struct ext4_extent *ex,
unsigned long from, unsigned long to)
{
struct buffer_head *bh;
int i;
#ifdef EXTENTS_STATS
{
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
unsigned short ee_len = le16_to_cpu(ex->ee_len);
spin_lock(&sbi->s_ext_stats_lock);
sbi->s_ext_blocks += ee_len;
sbi->s_ext_extents++;
if (ee_len < sbi->s_ext_min)
sbi->s_ext_min = ee_len;
if (ee_len > sbi->s_ext_max)
sbi->s_ext_max = ee_len;
if (ext_depth(inode) > sbi->s_depth_max)
sbi->s_depth_max = ext_depth(inode);
spin_unlock(&sbi->s_ext_stats_lock);
}
#endif
if (from >= le32_to_cpu(ex->ee_block)
&& to == le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) {
/* tail removal */
unsigned long num, start;
num = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - from;
start = le32_to_cpu(ex->ee_start) + le16_to_cpu(ex->ee_len) - num;
ext_debug("free last %lu blocks starting %lu\n", num, start);
for (i = 0; i < num; i++) {
bh = sb_find_get_block(inode->i_sb, start + i);
ext4_forget(handle, 0, inode, bh, start + i);
}
ext4_free_blocks(handle, inode, start, num);
} else if (from == le32_to_cpu(ex->ee_block)
&& to <= le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) {
printk("strange request: removal %lu-%lu from %u:%u\n",
from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len));
} else {
printk("strange request: removal(2) %lu-%lu from %u:%u\n",
from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len));
}
return 0;
}
static int
ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
struct ext4_ext_path *path, unsigned long start)
{
int err = 0, correct_index = 0;
int depth = ext_depth(inode), credits;
struct ext4_extent_header *eh;
unsigned a, b, block, num;
unsigned long ex_ee_block;
unsigned short ex_ee_len;
struct ext4_extent *ex;
ext_debug("truncate since %lu in leaf\n", start);
if (!path[depth].p_hdr)
path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
eh = path[depth].p_hdr;
BUG_ON(eh == NULL);
BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
/* find where to start removing */
ex = EXT_LAST_EXTENT(eh);
ex_ee_block = le32_to_cpu(ex->ee_block);
ex_ee_len = le16_to_cpu(ex->ee_len);
while (ex >= EXT_FIRST_EXTENT(eh) &&
ex_ee_block + ex_ee_len > start) {
ext_debug("remove ext %lu:%u\n", ex_ee_block, ex_ee_len);
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;
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();
} 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();
} 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);
}
/* at present, extent can't cross block group */
/* leaf + bitmap + group desc + sb + inode */
credits = 5;
if (ex == EXT_FIRST_EXTENT(eh)) {
correct_index = 1;
credits += (ext_depth(inode)) + 1;
}
#ifdef CONFIG_QUOTA
credits += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
#endif
handle = ext4_ext_journal_restart(handle, credits);
if (IS_ERR(handle)) {
err = PTR_ERR(handle);
goto out;
}
err = ext4_ext_get_access(handle, inode, path + depth);
if (err)
goto out;
err = ext4_remove_blocks(handle, inode, ex, a, b);
if (err)
goto out;
if (num == 0) {
/* this extent is removed entirely mark slot unused */
ex->ee_start = 0;
eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1);
}
ex->ee_block = cpu_to_le32(block);
ex->ee_len = cpu_to_le16(num);
err = ext4_ext_dirty(handle, inode, path + depth);
if (err)
goto out;
ext_debug("new extent: %u:%u:%u\n", block, num,
le32_to_cpu(ex->ee_start));
ex--;
ex_ee_block = le32_to_cpu(ex->ee_block);
ex_ee_len = le16_to_cpu(ex->ee_len);
}
if (correct_index && eh->eh_entries)
err = ext4_ext_correct_indexes(handle, inode, path);
/* if this leaf is free, then we should
* remove it from index block above */
if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
err = ext4_ext_rm_idx(handle, inode, path + depth);
out:
return err;
}
/*
* returns 1 if current index have to be freed (even partial)
*/
static int inline
ext4_ext_more_to_rm(struct ext4_ext_path *path)
{
BUG_ON(path->p_idx == NULL);
if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
return 0;
/*
* if truncate on deeper level happened it it wasn't partial
* so we have to consider current index for truncation
*/
if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block)
return 0;
return 1;
}
int ext4_ext_remove_space(struct inode *inode, unsigned long start)
{
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;
ext_debug("truncate since %lu\n", start);
/* probably first extent we're gonna free will be last in block */
handle = ext4_journal_start(inode, depth + 1);
if (IS_ERR(handle))
return PTR_ERR(handle);
ext4_ext_invalidate_cache(inode);
/*
* we start scanning from right side freeing all the blocks
* after i_size and walking into the deep
*/
path = kmalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_KERNEL);
if (path == NULL) {
ext4_journal_stop(handle);
return -ENOMEM;
}
memset(path, 0, sizeof(struct ext4_ext_path) * (depth + 1));
path[0].p_hdr = ext_inode_hdr(inode);
if (ext4_ext_check_header(__FUNCTION__, inode, path[0].p_hdr)) {
err = -EIO;
goto out;
}
path[0].p_depth = depth;
while (i >= 0 && err == 0) {
if (i == depth) {
/* this is leaf block */
err = ext4_ext_rm_leaf(handle, inode, path, start);
/* root level have p_bh == NULL, brelse() eats this */
brelse(path[i].p_bh);
path[i].p_bh = NULL;
i--;
continue;
}
/* this is index block */
if (!path[i].p_hdr) {
ext_debug("initialize header\n");
path[i].p_hdr = ext_block_hdr(path[i].p_bh);
if (ext4_ext_check_header(__FUNCTION__, inode,
path[i].p_hdr)) {
err = -EIO;
goto out;
}
}
BUG_ON(le16_to_cpu(path[i].p_hdr->eh_entries)
> le16_to_cpu(path[i].p_hdr->eh_max));
BUG_ON(path[i].p_hdr->eh_magic != EXT4_EXT_MAGIC);
if (!path[i].p_idx) {
/* this level hasn't touched yet */
path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr);
path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1;
ext_debug("init index ptr: hdr 0x%p, num %d\n",
path[i].p_hdr,
le16_to_cpu(path[i].p_hdr->eh_entries));
} else {
/* we've already was here, see at next index */
path[i].p_idx--;
}
ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
i, EXT_FIRST_INDEX(path[i].p_hdr),
path[i].p_idx);
if (ext4_ext_more_to_rm(path + i)) {
/* go to the next level */
ext_debug("move to level %d (block %d)\n",
i + 1, le32_to_cpu(path[i].p_idx->ei_leaf));
memset(path + i + 1, 0, sizeof(*path));
path[i+1].p_bh =
sb_bread(sb, le32_to_cpu(path[i].p_idx->ei_leaf));
if (!path[i+1].p_bh) {
/* should we reset i_size? */
err = -EIO;
break;
}
/* put actual number of indexes to know is this
* number got changed at the next iteration */
path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries);
i++;
} else {
/* we finish processing this index, go up */
if (path[i].p_hdr->eh_entries == 0 && i > 0) {
/* index is empty, remove it
* handle must be already prepared by the
* truncatei_leaf() */
err = ext4_ext_rm_idx(handle, inode, path + i);
}
/* root level have p_bh == NULL, brelse() eats this */
brelse(path[i].p_bh);
path[i].p_bh = NULL;
i--;
ext_debug("return to level %d\n", i);
}
}
/* TODO: flexible tree reduction should be here */
if (path->p_hdr->eh_entries == 0) {
/*
* truncate to zero freed all the tree
* so, we need to correct eh_depth
*/
err = ext4_ext_get_access(handle, inode, path);
if (err == 0) {
ext_inode_hdr(inode)->eh_depth = 0;
ext_inode_hdr(inode)->eh_max =
cpu_to_le16(ext4_ext_space_root(inode));
err = ext4_ext_dirty(handle, inode, path);
}
}
out:
ext4_ext_tree_changed(inode);
ext4_ext_drop_refs(path);
kfree(path);
ext4_journal_stop(handle);
return err;
}
/*
* called at mount time
*/
void ext4_ext_init(struct super_block *sb)
{
/*
* possible initialization would be here
*/
if (test_opt(sb, EXTENTS)) {
printk("EXT4-fs: file extents enabled");
#ifdef AGRESSIVE_TEST
printk(", agressive tests");
#endif
#ifdef CHECK_BINSEARCH
printk(", check binsearch");
#endif
#ifdef EXTENTS_STATS
printk(", stats");
#endif
printk("\n");
#ifdef EXTENTS_STATS
spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
EXT4_SB(sb)->s_ext_min = 1 << 30;
EXT4_SB(sb)->s_ext_max = 0;
#endif
}
}
/*
* called at umount time
*/
void ext4_ext_release(struct super_block *sb)
{
if (!test_opt(sb, EXTENTS))
return;
#ifdef EXTENTS_STATS
if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) {
struct ext4_sb_info *sbi = EXT4_SB(sb);
printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
sbi->s_ext_blocks, sbi->s_ext_extents,
sbi->s_ext_blocks / sbi->s_ext_extents);
printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max);
}
#endif
}
int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, sector_t iblock,
unsigned long max_blocks, struct buffer_head *bh_result,
int create, int extend_disksize)
{
struct ext4_ext_path *path = NULL;
struct ext4_extent newex, *ex;
int goal, newblock, err = 0, depth;
unsigned long allocated = 0;
__clear_bit(BH_New, &bh_result->b_state);
ext_debug("blocks %d/%lu requested for inode %u\n", (int) iblock,
max_blocks, (unsigned) inode->i_ino);
mutex_lock(&EXT4_I(inode)->truncate_mutex);
/* check in cache */
if ((goal = ext4_ext_in_cache(inode, iblock, &newex))) {
if (goal == EXT4_EXT_CACHE_GAP) {
if (!create) {
/* block isn't allocated yet and
* user don't want to allocate it */
goto out2;
}
/* we should allocate requested block */
} else if (goal == EXT4_EXT_CACHE_EXTENT) {
/* block is already allocated */
newblock = iblock
- le32_to_cpu(newex.ee_block)
+ le32_to_cpu(newex.ee_start);
/* number of remain blocks in the extent */
allocated = le16_to_cpu(newex.ee_len) -
(iblock - le32_to_cpu(newex.ee_block));
goto out;
} else {
BUG();
}
}
/* find extent for this block */
path = ext4_ext_find_extent(inode, iblock, NULL);
if (IS_ERR(path)) {
err = PTR_ERR(path);
path = NULL;
goto out2;
}
depth = ext_depth(inode);
/*
* consistent leaf must not be empty
* this situations is possible, though, _during_ tree modification
* this is why assert can't be put in ext4_ext_find_extent()
*/
BUG_ON(path[depth].p_ext == NULL && depth != 0);
if ((ex = path[depth].p_ext)) {
unsigned long ee_block = le32_to_cpu(ex->ee_block);
unsigned long ee_start = le32_to_cpu(ex->ee_start);
unsigned short ee_len = le16_to_cpu(ex->ee_len);
/* if found exent covers block, simple return it */
if (iblock >= ee_block && iblock < ee_block + ee_len) {
newblock = iblock - ee_block + ee_start;
/* number of remain blocks in the extent */
allocated = ee_len - (iblock - ee_block);
ext_debug("%d fit into %lu:%d -> %d\n", (int) iblock,
ee_block, ee_len, newblock);
ext4_ext_put_in_cache(inode, ee_block, ee_len,
ee_start, EXT4_EXT_CACHE_EXTENT);
goto out;
}
}
/*
* requested block isn't allocated yet
* we couldn't try to create block if create flag is zero
*/
if (!create) {
/* put just found gap into cache to speedup subsequest reqs */
ext4_ext_put_gap_in_cache(inode, path, iblock);
goto out2;
}
/*
* Okay, we need to do block allocation. Lazily initialize the block
* allocation info here if necessary
*/
if (S_ISREG(inode->i_mode) && (!EXT4_I(inode)->i_block_alloc_info))
ext4_init_block_alloc_info(inode);
/* allocate new block */
goal = ext4_ext_find_goal(inode, path, iblock);
allocated = max_blocks;
newblock = ext4_new_blocks(handle, inode, goal, &allocated, &err);
if (!newblock)
goto out2;
ext_debug("allocate new block: goal %d, found %d/%lu\n",
goal, newblock, allocated);
/* try to insert new extent into found leaf and return */
newex.ee_block = cpu_to_le32(iblock);
newex.ee_start = cpu_to_le32(newblock);
newex.ee_len = cpu_to_le16(allocated);
err = ext4_ext_insert_extent(handle, inode, path, &newex);
if (err)
goto out2;
if (extend_disksize && inode->i_size > EXT4_I(inode)->i_disksize)
EXT4_I(inode)->i_disksize = inode->i_size;
/* previous routine could use block we allocated */
newblock = le32_to_cpu(newex.ee_start);
__set_bit(BH_New, &bh_result->b_state);
ext4_ext_put_in_cache(inode, iblock, allocated, newblock,
EXT4_EXT_CACHE_EXTENT);
out:
if (allocated > max_blocks)
allocated = max_blocks;
ext4_ext_show_leaf(inode, path);
__set_bit(BH_Mapped, &bh_result->b_state);
bh_result->b_bdev = inode->i_sb->s_bdev;
bh_result->b_blocknr = newblock;
out2:
if (path) {
ext4_ext_drop_refs(path);
kfree(path);
}
mutex_unlock(&EXT4_I(inode)->truncate_mutex);
return err ? err : allocated;
}
void ext4_ext_truncate(struct inode * inode, struct page *page)
{
struct address_space *mapping = inode->i_mapping;
struct super_block *sb = inode->i_sb;
unsigned long last_block;
handle_t *handle;
int err = 0;
/*
* probably first extent we're gonna free will be last in block
*/
err = ext4_writepage_trans_blocks(inode) + 3;
handle = ext4_journal_start(inode, err);
if (IS_ERR(handle)) {
if (page) {
clear_highpage(page);
flush_dcache_page(page);
unlock_page(page);
page_cache_release(page);
}
return;
}
if (page)
ext4_block_truncate_page(handle, page, mapping, inode->i_size);
mutex_lock(&EXT4_I(inode)->truncate_mutex);
ext4_ext_invalidate_cache(inode);
/*
* TODO: optimization is possible here
* probably we need not scaning at all,
* because page truncation is enough
*/
if (ext4_orphan_add(handle, inode))
goto out_stop;
/* we have to know where to truncate from in crash case */
EXT4_I(inode)->i_disksize = inode->i_size;
ext4_mark_inode_dirty(handle, inode);
last_block = (inode->i_size + sb->s_blocksize - 1)
>> EXT4_BLOCK_SIZE_BITS(sb);
err = ext4_ext_remove_space(inode, last_block);
/* In a multi-transaction truncate, we only make the final
* transaction synchronous */
if (IS_SYNC(inode))
handle->h_sync = 1;
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.
* However, if this was a real unlink then we were called by
* ext4_delete_inode(), and we allow that function to clean up the
* orphan info for us.
*/
if (inode->i_nlink)
ext4_orphan_del(handle, inode);
mutex_unlock(&EXT4_I(inode)->truncate_mutex);
ext4_journal_stop(handle);
}
/*
* this routine calculate max number of blocks we could modify
* in order to allocate new block for an inode
*/
int ext4_ext_writepage_trans_blocks(struct inode *inode, int num)
{
int needed;
needed = ext4_ext_calc_credits_for_insert(inode, NULL);
/* caller want to allocate num blocks, but note it includes sb */
needed = needed * num - (num - 1);
#ifdef CONFIG_QUOTA
needed += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
#endif
return needed;
}
EXPORT_SYMBOL(ext4_mark_inode_dirty);
EXPORT_SYMBOL(ext4_ext_invalidate_cache);
EXPORT_SYMBOL(ext4_ext_insert_extent);
EXPORT_SYMBOL(ext4_ext_walk_space);
EXPORT_SYMBOL(ext4_ext_find_goal);
EXPORT_SYMBOL(ext4_ext_calc_credits_for_insert);
......@@ -615,6 +615,17 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode * dir, int mode)
ext4_std_error(sb, err);
goto fail_free_drop;
}
if (test_opt(sb, EXTENTS)) {
EXT4_I(inode)->i_flags |= EXT4_EXTENTS_FL;
ext4_ext_tree_init(handle, inode);
if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
if (err) goto fail;
EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS);
BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "call ext4_journal_dirty_metadata");
err = ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh);
}
}
ext4_debug("allocating inode %lu\n", inode->i_ino);
goto really_out;
......
......@@ -40,8 +40,6 @@
#include "xattr.h"
#include "acl.h"
static int ext4_writepage_trans_blocks(struct inode *inode);
/*
* Test whether an inode is a fast symlink.
*/
......@@ -804,6 +802,7 @@ int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
ext4_fsblk_t first_block = 0;
J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL));
J_ASSERT(handle != NULL || create == 0);
depth = ext4_block_to_path(inode,iblock,offsets,&blocks_to_boundary);
......@@ -984,7 +983,7 @@ static int ext4_get_block(struct inode *inode, sector_t iblock,
get_block:
if (ret == 0) {
ret = ext4_get_blocks_handle(handle, inode, iblock,
ret = ext4_get_blocks_wrap(handle, inode, iblock,
max_blocks, bh_result, create, 0);
if (ret > 0) {
bh_result->b_size = (ret << inode->i_blkbits);
......@@ -1008,7 +1007,7 @@ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode,
dummy.b_state = 0;
dummy.b_blocknr = -1000;
buffer_trace_init(&dummy.b_history);
err = ext4_get_blocks_handle(handle, inode, block, 1,
err = ext4_get_blocks_wrap(handle, inode, block, 1,
&dummy, create, 1);
/*
* ext4_get_blocks_handle() returns number of blocks
......@@ -1759,7 +1758,7 @@ void ext4_set_aops(struct inode *inode)
* This required during truncate. We need to physically zero the tail end
* of that block so it doesn't yield old data if the file is later grown.
*/
static int ext4_block_truncate_page(handle_t *handle, struct page *page,
int ext4_block_truncate_page(handle_t *handle, struct page *page,
struct address_space *mapping, loff_t from)
{
ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT;
......@@ -2263,6 +2262,9 @@ void ext4_truncate(struct inode *inode)
return;
}
if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
return ext4_ext_truncate(inode, page);
handle = start_transaction(inode);
if (IS_ERR(handle)) {
if (page) {
......@@ -3003,12 +3005,15 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
* block and work out the exact number of indirects which are touched. Pah.
*/
static int ext4_writepage_trans_blocks(struct inode *inode)
int ext4_writepage_trans_blocks(struct inode *inode)
{
int bpp = ext4_journal_blocks_per_page(inode);
int indirects = (EXT4_NDIR_BLOCKS % bpp) ? 5 : 3;
int ret;
if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
return ext4_ext_writepage_trans_blocks(inode, bpp);
if (ext4_should_journal_data(inode))
ret = 3 * (bpp + indirects) + 2;
else
......
......@@ -248,7 +248,6 @@ int ext4_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
return err;
}
default:
return -ENOTTY;
}
......
......@@ -390,6 +390,7 @@ static void ext4_put_super (struct super_block * sb)
struct ext4_super_block *es = sbi->s_es;
int i;
ext4_ext_release(sb);
ext4_xattr_put_super(sb);
jbd2_journal_destroy(sbi->s_journal);
if (!(sb->s_flags & MS_RDONLY)) {
......@@ -454,6 +455,7 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
#endif
ei->i_block_alloc_info = NULL;
ei->vfs_inode.i_version = 1;
memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
return &ei->vfs_inode;
}
......@@ -677,7 +679,7 @@ enum {
Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
Opt_grpquota
Opt_grpquota, Opt_extents,
};
static match_table_t tokens = {
......@@ -727,6 +729,7 @@ static match_table_t tokens = {
{Opt_quota, "quota"},
{Opt_usrquota, "usrquota"},
{Opt_barrier, "barrier=%u"},
{Opt_extents, "extents"},
{Opt_err, NULL},
{Opt_resize, "resize"},
};
......@@ -1059,6 +1062,9 @@ static int parse_options (char *options, struct super_block *sb,
case Opt_bh:
clear_opt(sbi->s_mount_opt, NOBH);
break;
case Opt_extents:
set_opt (sbi->s_mount_opt, EXTENTS);
break;
default:
printk (KERN_ERR
"EXT4-fs: Unrecognized mount option \"%s\" "
......@@ -1787,6 +1793,8 @@ static int ext4_fill_super (struct super_block *sb, void *data, int silent)
test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA ? "ordered":
"writeback");
ext4_ext_init(sb);
lock_kernel();
return 0;
......
......@@ -178,8 +178,9 @@ struct ext4_group_desc
#define EXT4_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
#define EXT4_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
#define EXT4_RESERVED_FL 0x80000000 /* reserved for ext4 lib */
#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
#define EXT4_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
#define EXT4_FL_USER_VISIBLE 0x000BDFFF /* User visible flags */
#define EXT4_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */
/*
......@@ -384,6 +385,7 @@ struct ext4_inode {
#define EXT4_MOUNT_QUOTA 0x80000 /* Some quota option set */
#define EXT4_MOUNT_USRQUOTA 0x100000 /* "old" user quota */
#define EXT4_MOUNT_GRPQUOTA 0x200000 /* "old" group quota */
#define EXT4_MOUNT_EXTENTS 0x400000 /* Extents support */
/* Compatibility, for having both ext2_fs.h and ext4_fs.h included at once */
#ifndef _LINUX_EXT2_FS_H
......@@ -582,11 +584,13 @@ static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
#define EXT4_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */
#define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
#define EXT4_FEATURE_INCOMPAT_META_BG 0x0010
#define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040 /* extents support */
#define EXT4_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR
#define EXT4_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \
EXT4_FEATURE_INCOMPAT_RECOVER| \
EXT4_FEATURE_INCOMPAT_META_BG)
EXT4_FEATURE_INCOMPAT_META_BG| \
EXT4_FEATURE_INCOMPAT_EXTENTS)
#define EXT4_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
......@@ -825,6 +829,9 @@ extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
extern void ext4_truncate (struct inode *);
extern void ext4_set_inode_flags(struct inode *);
extern void ext4_set_aops(struct inode *inode);
extern int ext4_writepage_trans_blocks(struct inode *);
extern int ext4_block_truncate_page(handle_t *handle, struct page *page,
struct address_space *mapping, loff_t from);
/* ioctl.c */
extern int ext4_ioctl (struct inode *, struct file *, unsigned int,
......@@ -879,6 +886,28 @@ extern struct inode_operations ext4_special_inode_operations;
extern struct inode_operations ext4_symlink_inode_operations;
extern struct inode_operations ext4_fast_symlink_inode_operations;
/* extents.c */
extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
ext4_fsblk_t iblock,
unsigned long max_blocks, struct buffer_head *bh_result,
int create, int extend_disksize);
extern void ext4_ext_truncate(struct inode *, struct page *);
extern void ext4_ext_init(struct super_block *);
extern void ext4_ext_release(struct super_block *);
static inline int
ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
unsigned long max_blocks, struct buffer_head *bh,
int create, int extend_disksize)
{
if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
return ext4_ext_get_blocks(handle, inode, block, max_blocks,
bh, create, extend_disksize);
return ext4_get_blocks_handle(handle, inode, block, max_blocks, bh,
create, extend_disksize);
}
#endif /* __KERNEL__ */
......
/*
* Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
* Written by Alex Tomas <alex@clusterfs.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public Licens
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
*/
#ifndef _LINUX_EXT4_EXTENTS
#define _LINUX_EXT4_EXTENTS
#include <linux/ext4_fs.h>
/*
* with AGRESSIVE_TEST defined capacity of index/leaf blocks
* become very little, so index split, in-depth growing and
* other hard changes happens much more often
* this is for debug purposes only
*/
#define AGRESSIVE_TEST_
/*
* with EXTENTS_STATS defined number of blocks and extents
* are collected in truncate path. they'll be showed at
* umount time
*/
#define EXTENTS_STATS__
/*
* if CHECK_BINSEARCH defined, then results of binary search
* will be checked by linear search
*/
#define CHECK_BINSEARCH__
/*
* if EXT_DEBUG is defined you can use 'extdebug' mount option
* to get lots of info what's going on
*/
#define EXT_DEBUG__
#ifdef EXT_DEBUG
#define ext_debug(a...) printk(a)
#else
#define ext_debug(a...)
#endif
/*
* if EXT_STATS is defined then stats numbers are collected
* these number will be displayed at umount time
*/
#define EXT_STATS_
/*
* ext4_inode has i_block array (60 bytes total)
* first 12 bytes store ext4_extent_header
* the remain stores array of ext4_extent
*/
/*
* this is extent on-disk structure
* it's used at the bottom of the tree
*/
struct ext4_extent {
__le32 ee_block; /* first logical block extent covers */
__le16 ee_len; /* number of blocks covered by extent */
__le16 ee_start_hi; /* high 16 bits of physical block */
__le32 ee_start; /* low 32 bigs of physical block */
};
/*
* this is index on-disk structure
* it's used at all the levels, but the bottom
*/
struct ext4_extent_idx {
__le32 ei_block; /* index covers logical blocks from 'block' */
__le32 ei_leaf; /* pointer to the physical block of the next *
* level. leaf or next index could bet here */
__le16 ei_leaf_hi; /* high 16 bits of physical block */
__u16 ei_unused;
};
/*
* each block (leaves and indexes), even inode-stored has header
*/
struct ext4_extent_header {
__le16 eh_magic; /* probably will support different formats */
__le16 eh_entries; /* number of valid entries */
__le16 eh_max; /* capacity of store in entries */
__le16 eh_depth; /* has tree real underlaying blocks? */
__le32 eh_generation; /* generation of the tree */
};
#define EXT4_EXT_MAGIC cpu_to_le16(0xf30a)
/*
* array of ext4_ext_path contains path to some extent
* creation/lookup routines use it for traversal/splitting/etc
* truncate uses it to simulate recursive walking
*/
struct ext4_ext_path {
__u32 p_block;
__u16 p_depth;
struct ext4_extent *p_ext;
struct ext4_extent_idx *p_idx;
struct ext4_extent_header *p_hdr;
struct buffer_head *p_bh;
};
/*
* structure for external API
*/
#define EXT4_EXT_CACHE_NO 0
#define EXT4_EXT_CACHE_GAP 1
#define EXT4_EXT_CACHE_EXTENT 2
/*
* to be called by ext4_ext_walk_space()
* negative retcode - error
* positive retcode - signal for ext4_ext_walk_space(), see below
* callback must return valid extent (passed or newly created)
*/
typedef int (*ext_prepare_callback)(struct inode *, struct ext4_ext_path *,
struct ext4_ext_cache *,
void *);
#define EXT_CONTINUE 0
#define EXT_BREAK 1
#define EXT_REPEAT 2
#define EXT_MAX_BLOCK 0xffffffff
#define EXT_FIRST_EXTENT(__hdr__) \
((struct ext4_extent *) (((char *) (__hdr__)) + \
sizeof(struct ext4_extent_header)))
#define EXT_FIRST_INDEX(__hdr__) \
((struct ext4_extent_idx *) (((char *) (__hdr__)) + \
sizeof(struct ext4_extent_header)))
#define EXT_HAS_FREE_INDEX(__path__) \
(le16_to_cpu((__path__)->p_hdr->eh_entries) \
< le16_to_cpu((__path__)->p_hdr->eh_max))
#define EXT_LAST_EXTENT(__hdr__) \
(EXT_FIRST_EXTENT((__hdr__)) + le16_to_cpu((__hdr__)->eh_entries) - 1)
#define EXT_LAST_INDEX(__hdr__) \
(EXT_FIRST_INDEX((__hdr__)) + le16_to_cpu((__hdr__)->eh_entries) - 1)
#define EXT_MAX_EXTENT(__hdr__) \
(EXT_FIRST_EXTENT((__hdr__)) + le16_to_cpu((__hdr__)->eh_max) - 1)
#define EXT_MAX_INDEX(__hdr__) \
(EXT_FIRST_INDEX((__hdr__)) + le16_to_cpu((__hdr__)->eh_max) - 1)
static inline struct ext4_extent_header *ext_inode_hdr(struct inode *inode)
{
return (struct ext4_extent_header *) EXT4_I(inode)->i_data;
}
static inline struct ext4_extent_header *ext_block_hdr(struct buffer_head *bh)
{
return (struct ext4_extent_header *) bh->b_data;
}
static inline unsigned short ext_depth(struct inode *inode)
{
return le16_to_cpu(ext_inode_hdr(inode)->eh_depth);
}
static inline void ext4_ext_tree_changed(struct inode *inode)
{
EXT4_I(inode)->i_ext_generation++;
}
static inline void
ext4_ext_invalidate_cache(struct inode *inode)
{
EXT4_I(inode)->i_cached_extent.ec_type = EXT4_EXT_CACHE_NO;
}
extern int ext4_extent_tree_init(handle_t *, struct inode *);
extern int ext4_ext_calc_credits_for_insert(struct inode *, struct ext4_ext_path *);
extern int ext4_ext_insert_extent(handle_t *, struct inode *, struct ext4_ext_path *, struct ext4_extent *);
extern int ext4_ext_walk_space(struct inode *, unsigned long, unsigned long, ext_prepare_callback, void *);
extern struct ext4_ext_path * ext4_ext_find_extent(struct inode *, int, struct ext4_ext_path *);
#endif /* _LINUX_EXT4_EXTENTS */
......@@ -64,6 +64,16 @@ struct ext4_block_alloc_info {
#define rsv_start rsv_window._rsv_start
#define rsv_end rsv_window._rsv_end
/*
* storage for cached extent
*/
struct ext4_ext_cache {
__u32 ec_start;
__u32 ec_block;
__u32 ec_len; /* must be 32bit to return holes */
__u32 ec_type;
};
/*
* third extended file system inode data in memory
*/
......@@ -142,6 +152,9 @@ struct ext4_inode_info {
*/
struct mutex truncate_mutex;
struct inode vfs_inode;
unsigned long i_ext_generation;
struct ext4_ext_cache i_cached_extent;
};
#endif /* _LINUX_EXT4_FS_I */
......@@ -78,6 +78,16 @@ struct ext4_sb_info {
char *s_qf_names[MAXQUOTAS]; /* Names of quota files with journalled quota */
int s_jquota_fmt; /* Format of quota to use */
#endif
#ifdef EXTENTS_STATS
/* ext4 extents stats */
unsigned long s_ext_min;
unsigned long s_ext_max;
unsigned long s_depth_max;
spinlock_t s_ext_stats_lock;
unsigned long s_ext_blocks;
unsigned long s_ext_extents;
#endif
};
#endif /* _LINUX_EXT4_FS_SB */
......@@ -26,9 +26,14 @@
*
* We may have to touch one inode, one bitmap buffer, up to three
* indirection blocks, the group and superblock summaries, and the data
* block to complete the transaction. */
* block to complete the transaction.
*
* For extents-enabled fs we may have to allocate and modify upto
* 5 levels of tree + root which is stored in inode. */
#define EXT4_SINGLEDATA_TRANS_BLOCKS 8U
#define EXT4_SINGLEDATA_TRANS_BLOCKS(sb) \
(EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS) \
|| test_opt(sb, EXTENTS) ? 27U : 8U)
/* Extended attribute operations touch at most two data buffers,
* two bitmap buffers, and two group summaries, in addition to the inode
......@@ -42,7 +47,7 @@
* superblock only gets updated once, of course, so don't bother
* counting that again for the quota updates. */
#define EXT4_DATA_TRANS_BLOCKS(sb) (EXT4_SINGLEDATA_TRANS_BLOCKS + \
#define EXT4_DATA_TRANS_BLOCKS(sb) (EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + \
EXT4_XATTR_TRANS_BLOCKS - 2 + \
2*EXT4_QUOTA_TRANS_BLOCKS(sb))
......@@ -78,9 +83,9 @@
/* Amount of blocks needed for quota insert/delete - we do some block writes
* but inode, sb and group updates are done only once */
#define EXT4_QUOTA_INIT_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_INIT_ALLOC*\
(EXT4_SINGLEDATA_TRANS_BLOCKS-3)+3+DQUOT_INIT_REWRITE) : 0)
(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)+3+DQUOT_INIT_REWRITE) : 0)
#define EXT4_QUOTA_DEL_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_DEL_ALLOC*\
(EXT4_SINGLEDATA_TRANS_BLOCKS-3)+3+DQUOT_DEL_REWRITE) : 0)
(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)+3+DQUOT_DEL_REWRITE) : 0)
#else
#define EXT4_QUOTA_TRANS_BLOCKS(sb) 0
#define EXT4_QUOTA_INIT_BLOCKS(sb) 0
......
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