linux-stable/fs/ext4/ialloc.c
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00

1470 lines
40 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/ext4/ialloc.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* BSD ufs-inspired inode and directory allocation by
* Stephen Tweedie (sct@redhat.com), 1993
* Big-endian to little-endian byte-swapping/bitmaps by
* David S. Miller (davem@caip.rutgers.edu), 1995
*/
#include <linux/time.h>
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/quotaops.h>
#include <linux/buffer_head.h>
#include <linux/random.h>
#include <linux/bitops.h>
#include <linux/blkdev.h>
#include <linux/cred.h>
#include <asm/byteorder.h>
#include "ext4.h"
#include "ext4_jbd2.h"
#include "xattr.h"
#include "acl.h"
#include <trace/events/ext4.h>
/*
* ialloc.c contains the inodes allocation and deallocation routines
*/
/*
* The free inodes are managed by bitmaps. A file system contains several
* blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
* block for inodes, N blocks for the inode table and data blocks.
*
* The file system contains group descriptors which are located after the
* super block. Each descriptor contains the number of the bitmap block and
* the free blocks count in the block.
*/
/*
* To avoid calling the atomic setbit hundreds or thousands of times, we only
* need to use it within a single byte (to ensure we get endianness right).
* We can use memset for the rest of the bitmap as there are no other users.
*/
void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
{
int i;
if (start_bit >= end_bit)
return;
ext4_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
ext4_set_bit(i, bitmap);
if (i < end_bit)
memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
}
/* Initializes an uninitialized inode bitmap */
static int ext4_init_inode_bitmap(struct super_block *sb,
struct buffer_head *bh,
ext4_group_t block_group,
struct ext4_group_desc *gdp)
{
struct ext4_group_info *grp;
struct ext4_sb_info *sbi = EXT4_SB(sb);
J_ASSERT_BH(bh, buffer_locked(bh));
/* If checksum is bad mark all blocks and inodes use to prevent
* allocation, essentially implementing a per-group read-only flag. */
if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) {
grp = ext4_get_group_info(sb, block_group);
if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
percpu_counter_sub(&sbi->s_freeclusters_counter,
grp->bb_free);
set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
int count;
count = ext4_free_inodes_count(sb, gdp);
percpu_counter_sub(&sbi->s_freeinodes_counter,
count);
}
set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state);
return -EFSBADCRC;
}
memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), sb->s_blocksize * 8,
bh->b_data);
ext4_inode_bitmap_csum_set(sb, block_group, gdp, bh,
EXT4_INODES_PER_GROUP(sb) / 8);
ext4_group_desc_csum_set(sb, block_group, gdp);
return 0;
}
void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate)
{
if (uptodate) {
set_buffer_uptodate(bh);
set_bitmap_uptodate(bh);
}
unlock_buffer(bh);
put_bh(bh);
}
static int ext4_validate_inode_bitmap(struct super_block *sb,
struct ext4_group_desc *desc,
ext4_group_t block_group,
struct buffer_head *bh)
{
ext4_fsblk_t blk;
struct ext4_group_info *grp = ext4_get_group_info(sb, block_group);
struct ext4_sb_info *sbi = EXT4_SB(sb);
if (buffer_verified(bh))
return 0;
if (EXT4_MB_GRP_IBITMAP_CORRUPT(grp))
return -EFSCORRUPTED;
ext4_lock_group(sb, block_group);
blk = ext4_inode_bitmap(sb, desc);
if (!ext4_inode_bitmap_csum_verify(sb, block_group, desc, bh,
EXT4_INODES_PER_GROUP(sb) / 8)) {
ext4_unlock_group(sb, block_group);
ext4_error(sb, "Corrupt inode bitmap - block_group = %u, "
"inode_bitmap = %llu", block_group, blk);
grp = ext4_get_group_info(sb, block_group);
if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
int count;
count = ext4_free_inodes_count(sb, desc);
percpu_counter_sub(&sbi->s_freeinodes_counter,
count);
}
set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state);
return -EFSBADCRC;
}
set_buffer_verified(bh);
ext4_unlock_group(sb, block_group);
return 0;
}
/*
* Read the inode allocation bitmap for a given block_group, reading
* into the specified slot in the superblock's bitmap cache.
*
* Return buffer_head of bitmap on success or NULL.
*/
static struct buffer_head *
ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
{
struct ext4_group_desc *desc;
struct buffer_head *bh = NULL;
ext4_fsblk_t bitmap_blk;
int err;
desc = ext4_get_group_desc(sb, block_group, NULL);
if (!desc)
return ERR_PTR(-EFSCORRUPTED);
bitmap_blk = ext4_inode_bitmap(sb, desc);
bh = sb_getblk(sb, bitmap_blk);
if (unlikely(!bh)) {
ext4_error(sb, "Cannot read inode bitmap - "
"block_group = %u, inode_bitmap = %llu",
block_group, bitmap_blk);
return ERR_PTR(-EIO);
}
if (bitmap_uptodate(bh))
goto verify;
lock_buffer(bh);
if (bitmap_uptodate(bh)) {
unlock_buffer(bh);
goto verify;
}
ext4_lock_group(sb, block_group);
if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
err = ext4_init_inode_bitmap(sb, bh, block_group, desc);
set_bitmap_uptodate(bh);
set_buffer_uptodate(bh);
set_buffer_verified(bh);
ext4_unlock_group(sb, block_group);
unlock_buffer(bh);
if (err) {
ext4_error(sb, "Failed to init inode bitmap for group "
"%u: %d", block_group, err);
goto out;
}
return bh;
}
ext4_unlock_group(sb, block_group);
if (buffer_uptodate(bh)) {
/*
* if not uninit if bh is uptodate,
* bitmap is also uptodate
*/
set_bitmap_uptodate(bh);
unlock_buffer(bh);
goto verify;
}
/*
* submit the buffer_head for reading
*/
trace_ext4_load_inode_bitmap(sb, block_group);
bh->b_end_io = ext4_end_bitmap_read;
get_bh(bh);
submit_bh(REQ_OP_READ, REQ_META | REQ_PRIO, bh);
wait_on_buffer(bh);
if (!buffer_uptodate(bh)) {
put_bh(bh);
ext4_error(sb, "Cannot read inode bitmap - "
"block_group = %u, inode_bitmap = %llu",
block_group, bitmap_blk);
return ERR_PTR(-EIO);
}
verify:
err = ext4_validate_inode_bitmap(sb, desc, block_group, bh);
if (err)
goto out;
return bh;
out:
put_bh(bh);
return ERR_PTR(err);
}
/*
* NOTE! When we get the inode, we're the only people
* that have access to it, and as such there are no
* race conditions we have to worry about. The inode
* is not on the hash-lists, and it cannot be reached
* through the filesystem because the directory entry
* has been deleted earlier.
*
* HOWEVER: we must make sure that we get no aliases,
* which means that we have to call "clear_inode()"
* _before_ we mark the inode not in use in the inode
* bitmaps. Otherwise a newly created file might use
* the same inode number (not actually the same pointer
* though), and then we'd have two inodes sharing the
* same inode number and space on the harddisk.
*/
void ext4_free_inode(handle_t *handle, struct inode *inode)
{
struct super_block *sb = inode->i_sb;
int is_directory;
unsigned long ino;
struct buffer_head *bitmap_bh = NULL;
struct buffer_head *bh2;
ext4_group_t block_group;
unsigned long bit;
struct ext4_group_desc *gdp;
struct ext4_super_block *es;
struct ext4_sb_info *sbi;
int fatal = 0, err, count, cleared;
struct ext4_group_info *grp;
if (!sb) {
printk(KERN_ERR "EXT4-fs: %s:%d: inode on "
"nonexistent device\n", __func__, __LINE__);
return;
}
if (atomic_read(&inode->i_count) > 1) {
ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: count=%d",
__func__, __LINE__, inode->i_ino,
atomic_read(&inode->i_count));
return;
}
if (inode->i_nlink) {
ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: nlink=%d\n",
__func__, __LINE__, inode->i_ino, inode->i_nlink);
return;
}
sbi = EXT4_SB(sb);
ino = inode->i_ino;
ext4_debug("freeing inode %lu\n", ino);
trace_ext4_free_inode(inode);
/*
* Note: we must free any quota before locking the superblock,
* as writing the quota to disk may need the lock as well.
*/
dquot_initialize(inode);
dquot_free_inode(inode);
dquot_drop(inode);
is_directory = S_ISDIR(inode->i_mode);
/* Do this BEFORE marking the inode not in use or returning an error */
ext4_clear_inode(inode);
es = EXT4_SB(sb)->s_es;
if (ino < EXT4_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
ext4_error(sb, "reserved or nonexistent inode %lu", ino);
goto error_return;
}
block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
/* Don't bother if the inode bitmap is corrupt. */
grp = ext4_get_group_info(sb, block_group);
if (IS_ERR(bitmap_bh)) {
fatal = PTR_ERR(bitmap_bh);
bitmap_bh = NULL;
goto error_return;
}
if (unlikely(EXT4_MB_GRP_IBITMAP_CORRUPT(grp))) {
fatal = -EFSCORRUPTED;
goto error_return;
}
BUFFER_TRACE(bitmap_bh, "get_write_access");
fatal = ext4_journal_get_write_access(handle, bitmap_bh);
if (fatal)
goto error_return;
fatal = -ESRCH;
gdp = ext4_get_group_desc(sb, block_group, &bh2);
if (gdp) {
BUFFER_TRACE(bh2, "get_write_access");
fatal = ext4_journal_get_write_access(handle, bh2);
}
ext4_lock_group(sb, block_group);
cleared = ext4_test_and_clear_bit(bit, bitmap_bh->b_data);
if (fatal || !cleared) {
ext4_unlock_group(sb, block_group);
goto out;
}
count = ext4_free_inodes_count(sb, gdp) + 1;
ext4_free_inodes_set(sb, gdp, count);
if (is_directory) {
count = ext4_used_dirs_count(sb, gdp) - 1;
ext4_used_dirs_set(sb, gdp, count);
percpu_counter_dec(&sbi->s_dirs_counter);
}
ext4_inode_bitmap_csum_set(sb, block_group, gdp, bitmap_bh,
EXT4_INODES_PER_GROUP(sb) / 8);
ext4_group_desc_csum_set(sb, block_group, gdp);
ext4_unlock_group(sb, block_group);
percpu_counter_inc(&sbi->s_freeinodes_counter);
if (sbi->s_log_groups_per_flex) {
ext4_group_t f = ext4_flex_group(sbi, block_group);
atomic_inc(&sbi->s_flex_groups[f].free_inodes);
if (is_directory)
atomic_dec(&sbi->s_flex_groups[f].used_dirs);
}
BUFFER_TRACE(bh2, "call ext4_handle_dirty_metadata");
fatal = ext4_handle_dirty_metadata(handle, NULL, bh2);
out:
if (cleared) {
BUFFER_TRACE(bitmap_bh, "call ext4_handle_dirty_metadata");
err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh);
if (!fatal)
fatal = err;
} else {
ext4_error(sb, "bit already cleared for inode %lu", ino);
if (gdp && !EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
int count;
count = ext4_free_inodes_count(sb, gdp);
percpu_counter_sub(&sbi->s_freeinodes_counter,
count);
}
set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state);
}
error_return:
brelse(bitmap_bh);
ext4_std_error(sb, fatal);
}
struct orlov_stats {
__u64 free_clusters;
__u32 free_inodes;
__u32 used_dirs;
};
/*
* Helper function for Orlov's allocator; returns critical information
* for a particular block group or flex_bg. If flex_size is 1, then g
* is a block group number; otherwise it is flex_bg number.
*/
static void get_orlov_stats(struct super_block *sb, ext4_group_t g,
int flex_size, struct orlov_stats *stats)
{
struct ext4_group_desc *desc;
struct flex_groups *flex_group = EXT4_SB(sb)->s_flex_groups;
if (flex_size > 1) {
stats->free_inodes = atomic_read(&flex_group[g].free_inodes);
stats->free_clusters = atomic64_read(&flex_group[g].free_clusters);
stats->used_dirs = atomic_read(&flex_group[g].used_dirs);
return;
}
desc = ext4_get_group_desc(sb, g, NULL);
if (desc) {
stats->free_inodes = ext4_free_inodes_count(sb, desc);
stats->free_clusters = ext4_free_group_clusters(sb, desc);
stats->used_dirs = ext4_used_dirs_count(sb, desc);
} else {
stats->free_inodes = 0;
stats->free_clusters = 0;
stats->used_dirs = 0;
}
}
/*
* Orlov's allocator for directories.
*
* We always try to spread first-level directories.
*
* If there are blockgroups with both free inodes and free blocks counts
* not worse than average we return one with smallest directory count.
* Otherwise we simply return a random group.
*
* For the rest rules look so:
*
* It's OK to put directory into a group unless
* it has too many directories already (max_dirs) or
* it has too few free inodes left (min_inodes) or
* it has too few free blocks left (min_blocks) or
* Parent's group is preferred, if it doesn't satisfy these
* conditions we search cyclically through the rest. If none
* of the groups look good we just look for a group with more
* free inodes than average (starting at parent's group).
*/
static int find_group_orlov(struct super_block *sb, struct inode *parent,
ext4_group_t *group, umode_t mode,
const struct qstr *qstr)
{
ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
struct ext4_sb_info *sbi = EXT4_SB(sb);
ext4_group_t real_ngroups = ext4_get_groups_count(sb);
int inodes_per_group = EXT4_INODES_PER_GROUP(sb);
unsigned int freei, avefreei, grp_free;
ext4_fsblk_t freeb, avefreec;
unsigned int ndirs;
int max_dirs, min_inodes;
ext4_grpblk_t min_clusters;
ext4_group_t i, grp, g, ngroups;
struct ext4_group_desc *desc;
struct orlov_stats stats;
int flex_size = ext4_flex_bg_size(sbi);
struct dx_hash_info hinfo;
ngroups = real_ngroups;
if (flex_size > 1) {
ngroups = (real_ngroups + flex_size - 1) >>
sbi->s_log_groups_per_flex;
parent_group >>= sbi->s_log_groups_per_flex;
}
freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
avefreei = freei / ngroups;
freeb = EXT4_C2B(sbi,
percpu_counter_read_positive(&sbi->s_freeclusters_counter));
avefreec = freeb;
do_div(avefreec, ngroups);
ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
if (S_ISDIR(mode) &&
((parent == d_inode(sb->s_root)) ||
(ext4_test_inode_flag(parent, EXT4_INODE_TOPDIR)))) {
int best_ndir = inodes_per_group;
int ret = -1;
if (qstr) {
hinfo.hash_version = DX_HASH_HALF_MD4;
hinfo.seed = sbi->s_hash_seed;
ext4fs_dirhash(qstr->name, qstr->len, &hinfo);
grp = hinfo.hash;
} else
grp = prandom_u32();
parent_group = (unsigned)grp % ngroups;
for (i = 0; i < ngroups; i++) {
g = (parent_group + i) % ngroups;
get_orlov_stats(sb, g, flex_size, &stats);
if (!stats.free_inodes)
continue;
if (stats.used_dirs >= best_ndir)
continue;
if (stats.free_inodes < avefreei)
continue;
if (stats.free_clusters < avefreec)
continue;
grp = g;
ret = 0;
best_ndir = stats.used_dirs;
}
if (ret)
goto fallback;
found_flex_bg:
if (flex_size == 1) {
*group = grp;
return 0;
}
/*
* We pack inodes at the beginning of the flexgroup's
* inode tables. Block allocation decisions will do
* something similar, although regular files will
* start at 2nd block group of the flexgroup. See
* ext4_ext_find_goal() and ext4_find_near().
*/
grp *= flex_size;
for (i = 0; i < flex_size; i++) {
if (grp+i >= real_ngroups)
break;
desc = ext4_get_group_desc(sb, grp+i, NULL);
if (desc && ext4_free_inodes_count(sb, desc)) {
*group = grp+i;
return 0;
}
}
goto fallback;
}
max_dirs = ndirs / ngroups + inodes_per_group / 16;
min_inodes = avefreei - inodes_per_group*flex_size / 4;
if (min_inodes < 1)
min_inodes = 1;
min_clusters = avefreec - EXT4_CLUSTERS_PER_GROUP(sb)*flex_size / 4;
/*
* Start looking in the flex group where we last allocated an
* inode for this parent directory
*/
if (EXT4_I(parent)->i_last_alloc_group != ~0) {
parent_group = EXT4_I(parent)->i_last_alloc_group;
if (flex_size > 1)
parent_group >>= sbi->s_log_groups_per_flex;
}
for (i = 0; i < ngroups; i++) {
grp = (parent_group + i) % ngroups;
get_orlov_stats(sb, grp, flex_size, &stats);
if (stats.used_dirs >= max_dirs)
continue;
if (stats.free_inodes < min_inodes)
continue;
if (stats.free_clusters < min_clusters)
continue;
goto found_flex_bg;
}
fallback:
ngroups = real_ngroups;
avefreei = freei / ngroups;
fallback_retry:
parent_group = EXT4_I(parent)->i_block_group;
for (i = 0; i < ngroups; i++) {
grp = (parent_group + i) % ngroups;
desc = ext4_get_group_desc(sb, grp, NULL);
if (desc) {
grp_free = ext4_free_inodes_count(sb, desc);
if (grp_free && grp_free >= avefreei) {
*group = grp;
return 0;
}
}
}
if (avefreei) {
/*
* The free-inodes counter is approximate, and for really small
* filesystems the above test can fail to find any blockgroups
*/
avefreei = 0;
goto fallback_retry;
}
return -1;
}
static int find_group_other(struct super_block *sb, struct inode *parent,
ext4_group_t *group, umode_t mode)
{
ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
ext4_group_t i, last, ngroups = ext4_get_groups_count(sb);
struct ext4_group_desc *desc;
int flex_size = ext4_flex_bg_size(EXT4_SB(sb));
/*
* Try to place the inode is the same flex group as its
* parent. If we can't find space, use the Orlov algorithm to
* find another flex group, and store that information in the
* parent directory's inode information so that use that flex
* group for future allocations.
*/
if (flex_size > 1) {
int retry = 0;
try_again:
parent_group &= ~(flex_size-1);
last = parent_group + flex_size;
if (last > ngroups)
last = ngroups;
for (i = parent_group; i < last; i++) {
desc = ext4_get_group_desc(sb, i, NULL);
if (desc && ext4_free_inodes_count(sb, desc)) {
*group = i;
return 0;
}
}
if (!retry && EXT4_I(parent)->i_last_alloc_group != ~0) {
retry = 1;
parent_group = EXT4_I(parent)->i_last_alloc_group;
goto try_again;
}
/*
* If this didn't work, use the Orlov search algorithm
* to find a new flex group; we pass in the mode to
* avoid the topdir algorithms.
*/
*group = parent_group + flex_size;
if (*group > ngroups)
*group = 0;
return find_group_orlov(sb, parent, group, mode, NULL);
}
/*
* Try to place the inode in its parent directory
*/
*group = parent_group;
desc = ext4_get_group_desc(sb, *group, NULL);
if (desc && ext4_free_inodes_count(sb, desc) &&
ext4_free_group_clusters(sb, desc))
return 0;
/*
* We're going to place this inode in a different blockgroup from its
* parent. We want to cause files in a common directory to all land in
* the same blockgroup. But we want files which are in a different
* directory which shares a blockgroup with our parent to land in a
* different blockgroup.
*
* So add our directory's i_ino into the starting point for the hash.
*/
*group = (*group + parent->i_ino) % ngroups;
/*
* Use a quadratic hash to find a group with a free inode and some free
* blocks.
*/
for (i = 1; i < ngroups; i <<= 1) {
*group += i;
if (*group >= ngroups)
*group -= ngroups;
desc = ext4_get_group_desc(sb, *group, NULL);
if (desc && ext4_free_inodes_count(sb, desc) &&
ext4_free_group_clusters(sb, desc))
return 0;
}
/*
* That failed: try linear search for a free inode, even if that group
* has no free blocks.
*/
*group = parent_group;
for (i = 0; i < ngroups; i++) {
if (++*group >= ngroups)
*group = 0;
desc = ext4_get_group_desc(sb, *group, NULL);
if (desc && ext4_free_inodes_count(sb, desc))
return 0;
}
return -1;
}
/*
* In no journal mode, if an inode has recently been deleted, we want
* to avoid reusing it until we're reasonably sure the inode table
* block has been written back to disk. (Yes, these values are
* somewhat arbitrary...)
*/
#define RECENTCY_MIN 5
#define RECENTCY_DIRTY 300
static int recently_deleted(struct super_block *sb, ext4_group_t group, int ino)
{
struct ext4_group_desc *gdp;
struct ext4_inode *raw_inode;
struct buffer_head *bh;
int inodes_per_block = EXT4_SB(sb)->s_inodes_per_block;
int offset, ret = 0;
int recentcy = RECENTCY_MIN;
u32 dtime, now;
gdp = ext4_get_group_desc(sb, group, NULL);
if (unlikely(!gdp))
return 0;
bh = sb_find_get_block(sb, ext4_inode_table(sb, gdp) +
(ino / inodes_per_block));
if (!bh || !buffer_uptodate(bh))
/*
* If the block is not in the buffer cache, then it
* must have been written out.
*/
goto out;
offset = (ino % inodes_per_block) * EXT4_INODE_SIZE(sb);
raw_inode = (struct ext4_inode *) (bh->b_data + offset);
/* i_dtime is only 32 bits on disk, but we only care about relative
* times in the range of a few minutes (i.e. long enough to sync a
* recently-deleted inode to disk), so using the low 32 bits of the
* clock (a 68 year range) is enough, see time_before32() */
dtime = le32_to_cpu(raw_inode->i_dtime);
now = ktime_get_real_seconds();
if (buffer_dirty(bh))
recentcy += RECENTCY_DIRTY;
if (dtime && time_before32(dtime, now) &&
time_before32(now, dtime + recentcy))
ret = 1;
out:
brelse(bh);
return ret;
}
static int find_inode_bit(struct super_block *sb, ext4_group_t group,
struct buffer_head *bitmap, unsigned long *ino)
{
next:
*ino = ext4_find_next_zero_bit((unsigned long *)
bitmap->b_data,
EXT4_INODES_PER_GROUP(sb), *ino);
if (*ino >= EXT4_INODES_PER_GROUP(sb))
return 0;
if ((EXT4_SB(sb)->s_journal == NULL) &&
recently_deleted(sb, group, *ino)) {
*ino = *ino + 1;
if (*ino < EXT4_INODES_PER_GROUP(sb))
goto next;
return 0;
}
return 1;
}
/*
* There are two policies for allocating an inode. If the new inode is
* a directory, then a forward search is made for a block group with both
* free space and a low directory-to-inode ratio; if that fails, then of
* the groups with above-average free space, that group with the fewest
* directories already is chosen.
*
* For other inodes, search forward from the parent directory's block
* group to find a free inode.
*/
struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
umode_t mode, const struct qstr *qstr,
__u32 goal, uid_t *owner, __u32 i_flags,
int handle_type, unsigned int line_no,
int nblocks)
{
struct super_block *sb;
struct buffer_head *inode_bitmap_bh = NULL;
struct buffer_head *group_desc_bh;
ext4_group_t ngroups, group = 0;
unsigned long ino = 0;
struct inode *inode;
struct ext4_group_desc *gdp = NULL;
struct ext4_inode_info *ei;
struct ext4_sb_info *sbi;
int ret2, err;
struct inode *ret;
ext4_group_t i;
ext4_group_t flex_group;
struct ext4_group_info *grp;
int encrypt = 0;
/* Cannot create files in a deleted directory */
if (!dir || !dir->i_nlink)
return ERR_PTR(-EPERM);
sb = dir->i_sb;
sbi = EXT4_SB(sb);
if (unlikely(ext4_forced_shutdown(sbi)))
return ERR_PTR(-EIO);
if ((ext4_encrypted_inode(dir) || DUMMY_ENCRYPTION_ENABLED(sbi)) &&
(S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) &&
!(i_flags & EXT4_EA_INODE_FL)) {
err = fscrypt_get_encryption_info(dir);
if (err)
return ERR_PTR(err);
if (!fscrypt_has_encryption_key(dir))
return ERR_PTR(-ENOKEY);
encrypt = 1;
}
if (!handle && sbi->s_journal && !(i_flags & EXT4_EA_INODE_FL)) {
#ifdef CONFIG_EXT4_FS_POSIX_ACL
struct posix_acl *p = get_acl(dir, ACL_TYPE_DEFAULT);
if (p) {
int acl_size = p->a_count * sizeof(ext4_acl_entry);
nblocks += (S_ISDIR(mode) ? 2 : 1) *
__ext4_xattr_set_credits(sb, NULL /* inode */,
NULL /* block_bh */, acl_size,
true /* is_create */);
posix_acl_release(p);
}
#endif
#ifdef CONFIG_SECURITY
{
int num_security_xattrs = 1;
#ifdef CONFIG_INTEGRITY
num_security_xattrs++;
#endif
/*
* We assume that security xattrs are never
* more than 1k. In practice they are under
* 128 bytes.
*/
nblocks += num_security_xattrs *
__ext4_xattr_set_credits(sb, NULL /* inode */,
NULL /* block_bh */, 1024,
true /* is_create */);
}
#endif
if (encrypt)
nblocks += __ext4_xattr_set_credits(sb,
NULL /* inode */, NULL /* block_bh */,
FSCRYPT_SET_CONTEXT_MAX_SIZE,
true /* is_create */);
}
ngroups = ext4_get_groups_count(sb);
trace_ext4_request_inode(dir, mode);
inode = new_inode(sb);
if (!inode)
return ERR_PTR(-ENOMEM);
ei = EXT4_I(inode);
/*
* Initialize owners and quota early so that we don't have to account
* for quota initialization worst case in standard inode creating
* transaction
*/
if (owner) {
inode->i_mode = mode;
i_uid_write(inode, owner[0]);
i_gid_write(inode, owner[1]);
} else if (test_opt(sb, GRPID)) {
inode->i_mode = mode;
inode->i_uid = current_fsuid();
inode->i_gid = dir->i_gid;
} else
inode_init_owner(inode, dir, mode);
if (ext4_has_feature_project(sb) &&
ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT))
ei->i_projid = EXT4_I(dir)->i_projid;
else
ei->i_projid = make_kprojid(&init_user_ns, EXT4_DEF_PROJID);
err = dquot_initialize(inode);
if (err)
goto out;
if (!goal)
goal = sbi->s_inode_goal;
if (goal && goal <= le32_to_cpu(sbi->s_es->s_inodes_count)) {
group = (goal - 1) / EXT4_INODES_PER_GROUP(sb);
ino = (goal - 1) % EXT4_INODES_PER_GROUP(sb);
ret2 = 0;
goto got_group;
}
if (S_ISDIR(mode))
ret2 = find_group_orlov(sb, dir, &group, mode, qstr);
else
ret2 = find_group_other(sb, dir, &group, mode);
got_group:
EXT4_I(dir)->i_last_alloc_group = group;
err = -ENOSPC;
if (ret2 == -1)
goto out;
/*
* Normally we will only go through one pass of this loop,
* unless we get unlucky and it turns out the group we selected
* had its last inode grabbed by someone else.
*/
for (i = 0; i < ngroups; i++, ino = 0) {
err = -EIO;
gdp = ext4_get_group_desc(sb, group, &group_desc_bh);
if (!gdp)
goto out;
/*
* Check free inodes count before loading bitmap.
*/
if (ext4_free_inodes_count(sb, gdp) == 0)
goto next_group;
grp = ext4_get_group_info(sb, group);
/* Skip groups with already-known suspicious inode tables */
if (EXT4_MB_GRP_IBITMAP_CORRUPT(grp))
goto next_group;
brelse(inode_bitmap_bh);
inode_bitmap_bh = ext4_read_inode_bitmap(sb, group);
/* Skip groups with suspicious inode tables */
if (EXT4_MB_GRP_IBITMAP_CORRUPT(grp) ||
IS_ERR(inode_bitmap_bh)) {
inode_bitmap_bh = NULL;
goto next_group;
}
repeat_in_this_group:
ret2 = find_inode_bit(sb, group, inode_bitmap_bh, &ino);
if (!ret2)
goto next_group;
if (group == 0 && (ino + 1) < EXT4_FIRST_INO(sb)) {
ext4_error(sb, "reserved inode found cleared - "
"inode=%lu", ino + 1);
goto next_group;
}
if (!handle) {
BUG_ON(nblocks <= 0);
handle = __ext4_journal_start_sb(dir->i_sb, line_no,
handle_type, nblocks,
0);
if (IS_ERR(handle)) {
err = PTR_ERR(handle);
ext4_std_error(sb, err);
goto out;
}
}
BUFFER_TRACE(inode_bitmap_bh, "get_write_access");
err = ext4_journal_get_write_access(handle, inode_bitmap_bh);
if (err) {
ext4_std_error(sb, err);
goto out;
}
ext4_lock_group(sb, group);
ret2 = ext4_test_and_set_bit(ino, inode_bitmap_bh->b_data);
if (ret2) {
/* Someone already took the bit. Repeat the search
* with lock held.
*/
ret2 = find_inode_bit(sb, group, inode_bitmap_bh, &ino);
if (ret2) {
ext4_set_bit(ino, inode_bitmap_bh->b_data);
ret2 = 0;
} else {
ret2 = 1; /* we didn't grab the inode */
}
}
ext4_unlock_group(sb, group);
ino++; /* the inode bitmap is zero-based */
if (!ret2)
goto got; /* we grabbed the inode! */
if (ino < EXT4_INODES_PER_GROUP(sb))
goto repeat_in_this_group;
next_group:
if (++group == ngroups)
group = 0;
}
err = -ENOSPC;
goto out;
got:
BUFFER_TRACE(inode_bitmap_bh, "call ext4_handle_dirty_metadata");
err = ext4_handle_dirty_metadata(handle, NULL, inode_bitmap_bh);
if (err) {
ext4_std_error(sb, err);
goto out;
}
BUFFER_TRACE(group_desc_bh, "get_write_access");
err = ext4_journal_get_write_access(handle, group_desc_bh);
if (err) {
ext4_std_error(sb, err);
goto out;
}
/* We may have to initialize the block bitmap if it isn't already */
if (ext4_has_group_desc_csum(sb) &&
gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
struct buffer_head *block_bitmap_bh;
block_bitmap_bh = ext4_read_block_bitmap(sb, group);
if (IS_ERR(block_bitmap_bh)) {
err = PTR_ERR(block_bitmap_bh);
goto out;
}
BUFFER_TRACE(block_bitmap_bh, "get block bitmap access");
err = ext4_journal_get_write_access(handle, block_bitmap_bh);
if (err) {
brelse(block_bitmap_bh);
ext4_std_error(sb, err);
goto out;
}
BUFFER_TRACE(block_bitmap_bh, "dirty block bitmap");
err = ext4_handle_dirty_metadata(handle, NULL, block_bitmap_bh);
/* recheck and clear flag under lock if we still need to */
ext4_lock_group(sb, group);
if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
ext4_free_group_clusters_set(sb, gdp,
ext4_free_clusters_after_init(sb, group, gdp));
ext4_block_bitmap_csum_set(sb, group, gdp,
block_bitmap_bh);
ext4_group_desc_csum_set(sb, group, gdp);
}
ext4_unlock_group(sb, group);
brelse(block_bitmap_bh);
if (err) {
ext4_std_error(sb, err);
goto out;
}
}
/* Update the relevant bg descriptor fields */
if (ext4_has_group_desc_csum(sb)) {
int free;
struct ext4_group_info *grp = ext4_get_group_info(sb, group);
down_read(&grp->alloc_sem); /* protect vs itable lazyinit */
ext4_lock_group(sb, group); /* while we modify the bg desc */
free = EXT4_INODES_PER_GROUP(sb) -
ext4_itable_unused_count(sb, gdp);
if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
free = 0;
}
/*
* Check the relative inode number against the last used
* relative inode number in this group. if it is greater
* we need to update the bg_itable_unused count
*/
if (ino > free)
ext4_itable_unused_set(sb, gdp,
(EXT4_INODES_PER_GROUP(sb) - ino));
up_read(&grp->alloc_sem);
} else {
ext4_lock_group(sb, group);
}
ext4_free_inodes_set(sb, gdp, ext4_free_inodes_count(sb, gdp) - 1);
if (S_ISDIR(mode)) {
ext4_used_dirs_set(sb, gdp, ext4_used_dirs_count(sb, gdp) + 1);
if (sbi->s_log_groups_per_flex) {
ext4_group_t f = ext4_flex_group(sbi, group);
atomic_inc(&sbi->s_flex_groups[f].used_dirs);
}
}
if (ext4_has_group_desc_csum(sb)) {
ext4_inode_bitmap_csum_set(sb, group, gdp, inode_bitmap_bh,
EXT4_INODES_PER_GROUP(sb) / 8);
ext4_group_desc_csum_set(sb, group, gdp);
}
ext4_unlock_group(sb, group);
BUFFER_TRACE(group_desc_bh, "call ext4_handle_dirty_metadata");
err = ext4_handle_dirty_metadata(handle, NULL, group_desc_bh);
if (err) {
ext4_std_error(sb, err);
goto out;
}
percpu_counter_dec(&sbi->s_freeinodes_counter);
if (S_ISDIR(mode))
percpu_counter_inc(&sbi->s_dirs_counter);
if (sbi->s_log_groups_per_flex) {
flex_group = ext4_flex_group(sbi, group);
atomic_dec(&sbi->s_flex_groups[flex_group].free_inodes);
}
inode->i_ino = ino + group * EXT4_INODES_PER_GROUP(sb);
/* This is the optimal IO size (for stat), not the fs block size */
inode->i_blocks = 0;
inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime =
current_time(inode);
memset(ei->i_data, 0, sizeof(ei->i_data));
ei->i_dir_start_lookup = 0;
ei->i_disksize = 0;
/* Don't inherit extent flag from directory, amongst others. */
ei->i_flags =
ext4_mask_flags(mode, EXT4_I(dir)->i_flags & EXT4_FL_INHERITED);
ei->i_flags |= i_flags;
ei->i_file_acl = 0;
ei->i_dtime = 0;
ei->i_block_group = group;
ei->i_last_alloc_group = ~0;
ext4_set_inode_flags(inode);
if (IS_DIRSYNC(inode))
ext4_handle_sync(handle);
if (insert_inode_locked(inode) < 0) {
/*
* Likely a bitmap corruption causing inode to be allocated
* twice.
*/
err = -EIO;
ext4_error(sb, "failed to insert inode %lu: doubly allocated?",
inode->i_ino);
goto out;
}
spin_lock(&sbi->s_next_gen_lock);
inode->i_generation = sbi->s_next_generation++;
spin_unlock(&sbi->s_next_gen_lock);
/* Precompute checksum seed for inode metadata */
if (ext4_has_metadata_csum(sb)) {
__u32 csum;
__le32 inum = cpu_to_le32(inode->i_ino);
__le32 gen = cpu_to_le32(inode->i_generation);
csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&inum,
sizeof(inum));
ei->i_csum_seed = ext4_chksum(sbi, csum, (__u8 *)&gen,
sizeof(gen));
}
ext4_clear_state_flags(ei); /* Only relevant on 32-bit archs */
ext4_set_inode_state(inode, EXT4_STATE_NEW);
ei->i_extra_isize = EXT4_SB(sb)->s_want_extra_isize;
ei->i_inline_off = 0;
if (ext4_has_feature_inline_data(sb))
ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
ret = inode;
err = dquot_alloc_inode(inode);
if (err)
goto fail_drop;
/*
* Since the encryption xattr will always be unique, create it first so
* that it's less likely to end up in an external xattr block and
* prevent its deduplication.
*/
if (encrypt) {
err = fscrypt_inherit_context(dir, inode, handle, true);
if (err)
goto fail_free_drop;
}
if (!(ei->i_flags & EXT4_EA_INODE_FL)) {
err = ext4_init_acl(handle, inode, dir);
if (err)
goto fail_free_drop;
err = ext4_init_security(handle, inode, dir, qstr);
if (err)
goto fail_free_drop;
}
if (ext4_has_feature_extents(sb)) {
/* set extent flag only for directory, file and normal symlink*/
if (S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode)) {
ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
ext4_ext_tree_init(handle, inode);
}
}
if (ext4_handle_valid(handle)) {
ei->i_sync_tid = handle->h_transaction->t_tid;
ei->i_datasync_tid = handle->h_transaction->t_tid;
}
err = ext4_mark_inode_dirty(handle, inode);
if (err) {
ext4_std_error(sb, err);
goto fail_free_drop;
}
ext4_debug("allocating inode %lu\n", inode->i_ino);
trace_ext4_allocate_inode(inode, dir, mode);
brelse(inode_bitmap_bh);
return ret;
fail_free_drop:
dquot_free_inode(inode);
fail_drop:
clear_nlink(inode);
unlock_new_inode(inode);
out:
dquot_drop(inode);
inode->i_flags |= S_NOQUOTA;
iput(inode);
brelse(inode_bitmap_bh);
return ERR_PTR(err);
}
/* Verify that we are loading a valid orphan from disk */
struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
{
unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count);
ext4_group_t block_group;
int bit;
struct buffer_head *bitmap_bh = NULL;
struct inode *inode = NULL;
int err = -EFSCORRUPTED;
if (ino < EXT4_FIRST_INO(sb) || ino > max_ino)
goto bad_orphan;
block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
if (IS_ERR(bitmap_bh)) {
ext4_error(sb, "inode bitmap error %ld for orphan %lu",
ino, PTR_ERR(bitmap_bh));
return (struct inode *) bitmap_bh;
}
/* Having the inode bit set should be a 100% indicator that this
* is a valid orphan (no e2fsck run on fs). Orphans also include
* inodes that were being truncated, so we can't check i_nlink==0.
*/
if (!ext4_test_bit(bit, bitmap_bh->b_data))
goto bad_orphan;
inode = ext4_iget(sb, ino);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
ext4_error(sb, "couldn't read orphan inode %lu (err %d)",
ino, err);
return inode;
}
/*
* If the orphans has i_nlinks > 0 then it should be able to
* be truncated, otherwise it won't be removed from the orphan
* list during processing and an infinite loop will result.
* Similarly, it must not be a bad inode.
*/
if ((inode->i_nlink && !ext4_can_truncate(inode)) ||
is_bad_inode(inode))
goto bad_orphan;
if (NEXT_ORPHAN(inode) > max_ino)
goto bad_orphan;
brelse(bitmap_bh);
return inode;
bad_orphan:
ext4_error(sb, "bad orphan inode %lu", ino);
if (bitmap_bh)
printk(KERN_ERR "ext4_test_bit(bit=%d, block=%llu) = %d\n",
bit, (unsigned long long)bitmap_bh->b_blocknr,
ext4_test_bit(bit, bitmap_bh->b_data));
if (inode) {
printk(KERN_ERR "is_bad_inode(inode)=%d\n",
is_bad_inode(inode));
printk(KERN_ERR "NEXT_ORPHAN(inode)=%u\n",
NEXT_ORPHAN(inode));
printk(KERN_ERR "max_ino=%lu\n", max_ino);
printk(KERN_ERR "i_nlink=%u\n", inode->i_nlink);
/* Avoid freeing blocks if we got a bad deleted inode */
if (inode->i_nlink == 0)
inode->i_blocks = 0;
iput(inode);
}
brelse(bitmap_bh);
return ERR_PTR(err);
}
unsigned long ext4_count_free_inodes(struct super_block *sb)
{
unsigned long desc_count;
struct ext4_group_desc *gdp;
ext4_group_t i, ngroups = ext4_get_groups_count(sb);
#ifdef EXT4FS_DEBUG
struct ext4_super_block *es;
unsigned long bitmap_count, x;
struct buffer_head *bitmap_bh = NULL;
es = EXT4_SB(sb)->s_es;
desc_count = 0;
bitmap_count = 0;
gdp = NULL;
for (i = 0; i < ngroups; i++) {
gdp = ext4_get_group_desc(sb, i, NULL);
if (!gdp)
continue;
desc_count += ext4_free_inodes_count(sb, gdp);
brelse(bitmap_bh);
bitmap_bh = ext4_read_inode_bitmap(sb, i);
if (IS_ERR(bitmap_bh)) {
bitmap_bh = NULL;
continue;
}
x = ext4_count_free(bitmap_bh->b_data,
EXT4_INODES_PER_GROUP(sb) / 8);
printk(KERN_DEBUG "group %lu: stored = %d, counted = %lu\n",
(unsigned long) i, ext4_free_inodes_count(sb, gdp), x);
bitmap_count += x;
}
brelse(bitmap_bh);
printk(KERN_DEBUG "ext4_count_free_inodes: "
"stored = %u, computed = %lu, %lu\n",
le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
return desc_count;
#else
desc_count = 0;
for (i = 0; i < ngroups; i++) {
gdp = ext4_get_group_desc(sb, i, NULL);
if (!gdp)
continue;
desc_count += ext4_free_inodes_count(sb, gdp);
cond_resched();
}
return desc_count;
#endif
}
/* Called at mount-time, super-block is locked */
unsigned long ext4_count_dirs(struct super_block * sb)
{
unsigned long count = 0;
ext4_group_t i, ngroups = ext4_get_groups_count(sb);
for (i = 0; i < ngroups; i++) {
struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
if (!gdp)
continue;
count += ext4_used_dirs_count(sb, gdp);
}
return count;
}
/*
* Zeroes not yet zeroed inode table - just write zeroes through the whole
* inode table. Must be called without any spinlock held. The only place
* where it is called from on active part of filesystem is ext4lazyinit
* thread, so we do not need any special locks, however we have to prevent
* inode allocation from the current group, so we take alloc_sem lock, to
* block ext4_new_inode() until we are finished.
*/
int ext4_init_inode_table(struct super_block *sb, ext4_group_t group,
int barrier)
{
struct ext4_group_info *grp = ext4_get_group_info(sb, group);
struct ext4_sb_info *sbi = EXT4_SB(sb);
struct ext4_group_desc *gdp = NULL;
struct buffer_head *group_desc_bh;
handle_t *handle;
ext4_fsblk_t blk;
int num, ret = 0, used_blks = 0;
/* This should not happen, but just to be sure check this */
if (sb_rdonly(sb)) {
ret = 1;
goto out;
}
gdp = ext4_get_group_desc(sb, group, &group_desc_bh);
if (!gdp)
goto out;
/*
* We do not need to lock this, because we are the only one
* handling this flag.
*/
if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED))
goto out;
handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
goto out;
}
down_write(&grp->alloc_sem);
/*
* If inode bitmap was already initialized there may be some
* used inodes so we need to skip blocks with used inodes in
* inode table.
*/
if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)))
used_blks = DIV_ROUND_UP((EXT4_INODES_PER_GROUP(sb) -
ext4_itable_unused_count(sb, gdp)),
sbi->s_inodes_per_block);
if ((used_blks < 0) || (used_blks > sbi->s_itb_per_group)) {
ext4_error(sb, "Something is wrong with group %u: "
"used itable blocks: %d; "
"itable unused count: %u",
group, used_blks,
ext4_itable_unused_count(sb, gdp));
ret = 1;
goto err_out;
}
blk = ext4_inode_table(sb, gdp) + used_blks;
num = sbi->s_itb_per_group - used_blks;
BUFFER_TRACE(group_desc_bh, "get_write_access");
ret = ext4_journal_get_write_access(handle,
group_desc_bh);
if (ret)
goto err_out;
/*
* Skip zeroout if the inode table is full. But we set the ZEROED
* flag anyway, because obviously, when it is full it does not need
* further zeroing.
*/
if (unlikely(num == 0))
goto skip_zeroout;
ext4_debug("going to zero out inode table in group %d\n",
group);
ret = sb_issue_zeroout(sb, blk, num, GFP_NOFS);
if (ret < 0)
goto err_out;
if (barrier)
blkdev_issue_flush(sb->s_bdev, GFP_NOFS, NULL);
skip_zeroout:
ext4_lock_group(sb, group);
gdp->bg_flags |= cpu_to_le16(EXT4_BG_INODE_ZEROED);
ext4_group_desc_csum_set(sb, group, gdp);
ext4_unlock_group(sb, group);
BUFFER_TRACE(group_desc_bh,
"call ext4_handle_dirty_metadata");
ret = ext4_handle_dirty_metadata(handle, NULL,
group_desc_bh);
err_out:
up_write(&grp->alloc_sem);
ext4_journal_stop(handle);
out:
return ret;
}