linux/fs/nilfs2/sufile.c
Ryusuke Konishi 0ec060d188 nilfs2: verify metadata sizes read from disk
Add code to check sizes of on-disk data of metadata files such as inode
size, segment usage size, DAT entry size, and checkpoint size.  Although
these sizes are read from disk, the current implementation doesn't check
them.

If these sizes are not sane on disk, it can cause out-of-range access to
metadata or memory access overrun on metadata block buffers due to
overflow in sundry calculations.

Both lower limit and upper limit of metadata sizes are verified to
prevent these issues.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Andreas Rohner <andreas.rohner@gmx.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:21:26 -07:00

1223 lines
32 KiB
C

/*
* sufile.c - NILFS segment usage file.
*
* Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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 License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* Written by Koji Sato <koji@osrg.net>.
* Revised by Ryusuke Konishi <ryusuke@osrg.net>.
*/
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/buffer_head.h>
#include <linux/errno.h>
#include <linux/nilfs2_fs.h>
#include "mdt.h"
#include "sufile.h"
/**
* struct nilfs_sufile_info - on-memory private data of sufile
* @mi: on-memory private data of metadata file
* @ncleansegs: number of clean segments
* @allocmin: lower limit of allocatable segment range
* @allocmax: upper limit of allocatable segment range
*/
struct nilfs_sufile_info {
struct nilfs_mdt_info mi;
unsigned long ncleansegs;/* number of clean segments */
__u64 allocmin; /* lower limit of allocatable segment range */
__u64 allocmax; /* upper limit of allocatable segment range */
};
static inline struct nilfs_sufile_info *NILFS_SUI(struct inode *sufile)
{
return (struct nilfs_sufile_info *)NILFS_MDT(sufile);
}
static inline unsigned long
nilfs_sufile_segment_usages_per_block(const struct inode *sufile)
{
return NILFS_MDT(sufile)->mi_entries_per_block;
}
static unsigned long
nilfs_sufile_get_blkoff(const struct inode *sufile, __u64 segnum)
{
__u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
return (unsigned long)t;
}
static unsigned long
nilfs_sufile_get_offset(const struct inode *sufile, __u64 segnum)
{
__u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
return do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
}
static unsigned long
nilfs_sufile_segment_usages_in_block(const struct inode *sufile, __u64 curr,
__u64 max)
{
return min_t(unsigned long,
nilfs_sufile_segment_usages_per_block(sufile) -
nilfs_sufile_get_offset(sufile, curr),
max - curr + 1);
}
static struct nilfs_segment_usage *
nilfs_sufile_block_get_segment_usage(const struct inode *sufile, __u64 segnum,
struct buffer_head *bh, void *kaddr)
{
return kaddr + bh_offset(bh) +
nilfs_sufile_get_offset(sufile, segnum) *
NILFS_MDT(sufile)->mi_entry_size;
}
static inline int nilfs_sufile_get_header_block(struct inode *sufile,
struct buffer_head **bhp)
{
return nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp);
}
static inline int
nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum,
int create, struct buffer_head **bhp)
{
return nilfs_mdt_get_block(sufile,
nilfs_sufile_get_blkoff(sufile, segnum),
create, NULL, bhp);
}
static int nilfs_sufile_delete_segment_usage_block(struct inode *sufile,
__u64 segnum)
{
return nilfs_mdt_delete_block(sufile,
nilfs_sufile_get_blkoff(sufile, segnum));
}
static void nilfs_sufile_mod_counter(struct buffer_head *header_bh,
u64 ncleanadd, u64 ndirtyadd)
{
struct nilfs_sufile_header *header;
void *kaddr;
kaddr = kmap_atomic(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
le64_add_cpu(&header->sh_ncleansegs, ncleanadd);
le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd);
kunmap_atomic(kaddr);
mark_buffer_dirty(header_bh);
}
/**
* nilfs_sufile_get_ncleansegs - return the number of clean segments
* @sufile: inode of segment usage file
*/
unsigned long nilfs_sufile_get_ncleansegs(struct inode *sufile)
{
return NILFS_SUI(sufile)->ncleansegs;
}
/**
* nilfs_sufile_updatev - modify multiple segment usages at a time
* @sufile: inode of segment usage file
* @segnumv: array of segment numbers
* @nsegs: size of @segnumv array
* @create: creation flag
* @ndone: place to store number of modified segments on @segnumv
* @dofunc: primitive operation for the update
*
* Description: nilfs_sufile_updatev() repeatedly calls @dofunc
* against the given array of segments. The @dofunc is called with
* buffers of a header block and the sufile block in which the target
* segment usage entry is contained. If @ndone is given, the number
* of successfully modified segments from the head is stored in the
* place @ndone points to.
*
* Return Value: On success, zero is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOENT - Given segment usage is in hole block (may be returned if
* @create is zero)
*
* %-EINVAL - Invalid segment usage number
*/
int nilfs_sufile_updatev(struct inode *sufile, __u64 *segnumv, size_t nsegs,
int create, size_t *ndone,
void (*dofunc)(struct inode *, __u64,
struct buffer_head *,
struct buffer_head *))
{
struct buffer_head *header_bh, *bh;
unsigned long blkoff, prev_blkoff;
__u64 *seg;
size_t nerr = 0, n = 0;
int ret = 0;
if (unlikely(nsegs == 0))
goto out;
down_write(&NILFS_MDT(sufile)->mi_sem);
for (seg = segnumv; seg < segnumv + nsegs; seg++) {
if (unlikely(*seg >= nilfs_sufile_get_nsegments(sufile))) {
printk(KERN_WARNING
"%s: invalid segment number: %llu\n", __func__,
(unsigned long long)*seg);
nerr++;
}
}
if (nerr > 0) {
ret = -EINVAL;
goto out_sem;
}
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
seg = segnumv;
blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
if (ret < 0)
goto out_header;
for (;;) {
dofunc(sufile, *seg, header_bh, bh);
if (++seg >= segnumv + nsegs)
break;
prev_blkoff = blkoff;
blkoff = nilfs_sufile_get_blkoff(sufile, *seg);
if (blkoff == prev_blkoff)
continue;
/* get different block */
brelse(bh);
ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh);
if (unlikely(ret < 0))
goto out_header;
}
brelse(bh);
out_header:
n = seg - segnumv;
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
out:
if (ndone)
*ndone = n;
return ret;
}
int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create,
void (*dofunc)(struct inode *, __u64,
struct buffer_head *,
struct buffer_head *))
{
struct buffer_head *header_bh, *bh;
int ret;
if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) {
printk(KERN_WARNING "%s: invalid segment number: %llu\n",
__func__, (unsigned long long)segnum);
return -EINVAL;
}
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, &bh);
if (!ret) {
dofunc(sufile, segnum, header_bh, bh);
brelse(bh);
}
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_set_alloc_range - limit range of segment to be allocated
* @sufile: inode of segment usage file
* @start: minimum segment number of allocatable region (inclusive)
* @end: maximum segment number of allocatable region (inclusive)
*
* Return Value: On success, 0 is returned. On error, one of the
* following negative error codes is returned.
*
* %-ERANGE - invalid segment region
*/
int nilfs_sufile_set_alloc_range(struct inode *sufile, __u64 start, __u64 end)
{
struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
__u64 nsegs;
int ret = -ERANGE;
down_write(&NILFS_MDT(sufile)->mi_sem);
nsegs = nilfs_sufile_get_nsegments(sufile);
if (start <= end && end < nsegs) {
sui->allocmin = start;
sui->allocmax = end;
ret = 0;
}
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_alloc - allocate a segment
* @sufile: inode of segment usage file
* @segnump: pointer to segment number
*
* Description: nilfs_sufile_alloc() allocates a clean segment.
*
* Return Value: On success, 0 is returned and the segment number of the
* allocated segment is stored in the place pointed by @segnump. On error, one
* of the following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOSPC - No clean segment left.
*/
int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
{
struct buffer_head *header_bh, *su_bh;
struct nilfs_sufile_header *header;
struct nilfs_segment_usage *su;
struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
__u64 segnum, maxsegnum, last_alloc;
void *kaddr;
unsigned long nsegments, ncleansegs, nsus, cnt;
int ret, j;
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
ncleansegs = le64_to_cpu(header->sh_ncleansegs);
last_alloc = le64_to_cpu(header->sh_last_alloc);
kunmap_atomic(kaddr);
nsegments = nilfs_sufile_get_nsegments(sufile);
maxsegnum = sui->allocmax;
segnum = last_alloc + 1;
if (segnum < sui->allocmin || segnum > sui->allocmax)
segnum = sui->allocmin;
for (cnt = 0; cnt < nsegments; cnt += nsus) {
if (segnum > maxsegnum) {
if (cnt < sui->allocmax - sui->allocmin + 1) {
/*
* wrap around in the limited region.
* if allocation started from
* sui->allocmin, this never happens.
*/
segnum = sui->allocmin;
maxsegnum = last_alloc;
} else if (segnum > sui->allocmin &&
sui->allocmax + 1 < nsegments) {
segnum = sui->allocmax + 1;
maxsegnum = nsegments - 1;
} else if (sui->allocmin > 0) {
segnum = 0;
maxsegnum = sui->allocmin - 1;
} else {
break; /* never happens */
}
}
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1,
&su_bh);
if (ret < 0)
goto out_header;
kaddr = kmap_atomic(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
nsus = nilfs_sufile_segment_usages_in_block(
sufile, segnum, maxsegnum);
for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) {
if (!nilfs_segment_usage_clean(su))
continue;
/* found a clean segment */
nilfs_segment_usage_set_dirty(su);
kunmap_atomic(kaddr);
kaddr = kmap_atomic(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
le64_add_cpu(&header->sh_ncleansegs, -1);
le64_add_cpu(&header->sh_ndirtysegs, 1);
header->sh_last_alloc = cpu_to_le64(segnum);
kunmap_atomic(kaddr);
sui->ncleansegs--;
mark_buffer_dirty(header_bh);
mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
brelse(su_bh);
*segnump = segnum;
goto out_header;
}
kunmap_atomic(kaddr);
brelse(su_bh);
}
/* no segments left */
ret = -ENOSPC;
out_header:
brelse(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
kaddr = kmap_atomic(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (unlikely(!nilfs_segment_usage_clean(su))) {
printk(KERN_WARNING "%s: segment %llu must be clean\n",
__func__, (unsigned long long)segnum);
kunmap_atomic(kaddr);
return;
}
nilfs_segment_usage_set_dirty(su);
kunmap_atomic(kaddr);
nilfs_sufile_mod_counter(header_bh, -1, 1);
NILFS_SUI(sufile)->ncleansegs--;
mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
}
void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
int clean, dirty;
kaddr = kmap_atomic(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (su->su_flags == cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY) &&
su->su_nblocks == cpu_to_le32(0)) {
kunmap_atomic(kaddr);
return;
}
clean = nilfs_segment_usage_clean(su);
dirty = nilfs_segment_usage_dirty(su);
/* make the segment garbage */
su->su_lastmod = cpu_to_le64(0);
su->su_nblocks = cpu_to_le32(0);
su->su_flags = cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY);
kunmap_atomic(kaddr);
nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1);
NILFS_SUI(sufile)->ncleansegs -= clean;
mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
}
void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
int sudirty;
kaddr = kmap_atomic(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (nilfs_segment_usage_clean(su)) {
printk(KERN_WARNING "%s: segment %llu is already clean\n",
__func__, (unsigned long long)segnum);
kunmap_atomic(kaddr);
return;
}
WARN_ON(nilfs_segment_usage_error(su));
WARN_ON(!nilfs_segment_usage_dirty(su));
sudirty = nilfs_segment_usage_dirty(su);
nilfs_segment_usage_set_clean(su);
kunmap_atomic(kaddr);
mark_buffer_dirty(su_bh);
nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0);
NILFS_SUI(sufile)->ncleansegs++;
nilfs_mdt_mark_dirty(sufile);
}
/**
* nilfs_sufile_mark_dirty - mark the buffer having a segment usage dirty
* @sufile: inode of segment usage file
* @segnum: segment number
*/
int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum)
{
struct buffer_head *bh;
int ret;
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
if (!ret) {
mark_buffer_dirty(bh);
nilfs_mdt_mark_dirty(sufile);
brelse(bh);
}
return ret;
}
/**
* nilfs_sufile_set_segment_usage - set usage of a segment
* @sufile: inode of segment usage file
* @segnum: segment number
* @nblocks: number of live blocks in the segment
* @modtime: modification time (option)
*/
int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum,
unsigned long nblocks, time_t modtime)
{
struct buffer_head *bh;
struct nilfs_segment_usage *su;
void *kaddr;
int ret;
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr);
WARN_ON(nilfs_segment_usage_error(su));
if (modtime)
su->su_lastmod = cpu_to_le64(modtime);
su->su_nblocks = cpu_to_le32(nblocks);
kunmap_atomic(kaddr);
mark_buffer_dirty(bh);
nilfs_mdt_mark_dirty(sufile);
brelse(bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_get_stat - get segment usage statistics
* @sufile: inode of segment usage file
* @stat: pointer to a structure of segment usage statistics
*
* Description: nilfs_sufile_get_stat() returns information about segment
* usage.
*
* Return Value: On success, 0 is returned, and segment usage information is
* stored in the place pointed by @stat. On error, one of the following
* negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*/
int nilfs_sufile_get_stat(struct inode *sufile, struct nilfs_sustat *sustat)
{
struct buffer_head *header_bh;
struct nilfs_sufile_header *header;
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
void *kaddr;
int ret;
down_read(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
kaddr = kmap_atomic(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
sustat->ss_nsegs = nilfs_sufile_get_nsegments(sufile);
sustat->ss_ncleansegs = le64_to_cpu(header->sh_ncleansegs);
sustat->ss_ndirtysegs = le64_to_cpu(header->sh_ndirtysegs);
sustat->ss_ctime = nilfs->ns_ctime;
sustat->ss_nongc_ctime = nilfs->ns_nongc_ctime;
spin_lock(&nilfs->ns_last_segment_lock);
sustat->ss_prot_seq = nilfs->ns_prot_seq;
spin_unlock(&nilfs->ns_last_segment_lock);
kunmap_atomic(kaddr);
brelse(header_bh);
out_sem:
up_read(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum,
struct buffer_head *header_bh,
struct buffer_head *su_bh)
{
struct nilfs_segment_usage *su;
void *kaddr;
int suclean;
kaddr = kmap_atomic(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
if (nilfs_segment_usage_error(su)) {
kunmap_atomic(kaddr);
return;
}
suclean = nilfs_segment_usage_clean(su);
nilfs_segment_usage_set_error(su);
kunmap_atomic(kaddr);
if (suclean) {
nilfs_sufile_mod_counter(header_bh, -1, 0);
NILFS_SUI(sufile)->ncleansegs--;
}
mark_buffer_dirty(su_bh);
nilfs_mdt_mark_dirty(sufile);
}
/**
* nilfs_sufile_truncate_range - truncate range of segment array
* @sufile: inode of segment usage file
* @start: start segment number (inclusive)
* @end: end segment number (inclusive)
*
* Return Value: On success, 0 is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-EINVAL - Invalid number of segments specified
*
* %-EBUSY - Dirty or active segments are present in the range
*/
static int nilfs_sufile_truncate_range(struct inode *sufile,
__u64 start, __u64 end)
{
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
struct buffer_head *header_bh;
struct buffer_head *su_bh;
struct nilfs_segment_usage *su, *su2;
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
unsigned long segusages_per_block;
unsigned long nsegs, ncleaned;
__u64 segnum;
void *kaddr;
ssize_t n, nc;
int ret;
int j;
nsegs = nilfs_sufile_get_nsegments(sufile);
ret = -EINVAL;
if (start > end || start >= nsegs)
goto out;
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out;
segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
ncleaned = 0;
for (segnum = start; segnum <= end; segnum += n) {
n = min_t(unsigned long,
segusages_per_block -
nilfs_sufile_get_offset(sufile, segnum),
end - segnum + 1);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
&su_bh);
if (ret < 0) {
if (ret != -ENOENT)
goto out_header;
/* hole */
continue;
}
kaddr = kmap_atomic(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
su2 = su;
for (j = 0; j < n; j++, su = (void *)su + susz) {
if ((le32_to_cpu(su->su_flags) &
~(1UL << NILFS_SEGMENT_USAGE_ERROR)) ||
nilfs_segment_is_active(nilfs, segnum + j)) {
ret = -EBUSY;
kunmap_atomic(kaddr);
brelse(su_bh);
goto out_header;
}
}
nc = 0;
for (su = su2, j = 0; j < n; j++, su = (void *)su + susz) {
if (nilfs_segment_usage_error(su)) {
nilfs_segment_usage_set_clean(su);
nc++;
}
}
kunmap_atomic(kaddr);
if (nc > 0) {
mark_buffer_dirty(su_bh);
ncleaned += nc;
}
brelse(su_bh);
if (n == segusages_per_block) {
/* make hole */
nilfs_sufile_delete_segment_usage_block(sufile, segnum);
}
}
ret = 0;
out_header:
if (ncleaned > 0) {
NILFS_SUI(sufile)->ncleansegs += ncleaned;
nilfs_sufile_mod_counter(header_bh, ncleaned, 0);
nilfs_mdt_mark_dirty(sufile);
}
brelse(header_bh);
out:
return ret;
}
/**
* nilfs_sufile_resize - resize segment array
* @sufile: inode of segment usage file
* @newnsegs: new number of segments
*
* Return Value: On success, 0 is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-ENOSPC - Enough free space is not left for shrinking
*
* %-EBUSY - Dirty or active segments exist in the region to be truncated
*/
int nilfs_sufile_resize(struct inode *sufile, __u64 newnsegs)
{
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
struct buffer_head *header_bh;
struct nilfs_sufile_header *header;
struct nilfs_sufile_info *sui = NILFS_SUI(sufile);
void *kaddr;
unsigned long nsegs, nrsvsegs;
int ret = 0;
down_write(&NILFS_MDT(sufile)->mi_sem);
nsegs = nilfs_sufile_get_nsegments(sufile);
if (nsegs == newnsegs)
goto out;
ret = -ENOSPC;
nrsvsegs = nilfs_nrsvsegs(nilfs, newnsegs);
if (newnsegs < nsegs && nsegs - newnsegs + nrsvsegs > sui->ncleansegs)
goto out;
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out;
if (newnsegs > nsegs) {
sui->ncleansegs += newnsegs - nsegs;
} else /* newnsegs < nsegs */ {
ret = nilfs_sufile_truncate_range(sufile, newnsegs, nsegs - 1);
if (ret < 0)
goto out_header;
sui->ncleansegs -= nsegs - newnsegs;
}
kaddr = kmap_atomic(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
header->sh_ncleansegs = cpu_to_le64(sui->ncleansegs);
kunmap_atomic(kaddr);
mark_buffer_dirty(header_bh);
nilfs_mdt_mark_dirty(sufile);
nilfs_set_nsegments(nilfs, newnsegs);
out_header:
brelse(header_bh);
out:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_get_suinfo -
* @sufile: inode of segment usage file
* @segnum: segment number to start looking
* @buf: array of suinfo
* @sisz: byte size of suinfo
* @nsi: size of suinfo array
*
* Description:
*
* Return Value: On success, 0 is returned and .... On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*/
ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf,
unsigned sisz, size_t nsi)
{
struct buffer_head *su_bh;
struct nilfs_segment_usage *su;
struct nilfs_suinfo *si = buf;
size_t susz = NILFS_MDT(sufile)->mi_entry_size;
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
void *kaddr;
unsigned long nsegs, segusages_per_block;
ssize_t n;
int ret, i, j;
down_read(&NILFS_MDT(sufile)->mi_sem);
segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile);
nsegs = min_t(unsigned long,
nilfs_sufile_get_nsegments(sufile) - segnum,
nsi);
for (i = 0; i < nsegs; i += n, segnum += n) {
n = min_t(unsigned long,
segusages_per_block -
nilfs_sufile_get_offset(sufile, segnum),
nsegs - i);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
&su_bh);
if (ret < 0) {
if (ret != -ENOENT)
goto out;
/* hole */
memset(si, 0, sisz * n);
si = (void *)si + sisz * n;
continue;
}
kaddr = kmap_atomic(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
for (j = 0; j < n;
j++, su = (void *)su + susz, si = (void *)si + sisz) {
si->sui_lastmod = le64_to_cpu(su->su_lastmod);
si->sui_nblocks = le32_to_cpu(su->su_nblocks);
si->sui_flags = le32_to_cpu(su->su_flags) &
~(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
if (nilfs_segment_is_active(nilfs, segnum + j))
si->sui_flags |=
(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
}
kunmap_atomic(kaddr);
brelse(su_bh);
}
ret = nsegs;
out:
up_read(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_set_suinfo - sets segment usage info
* @sufile: inode of segment usage file
* @buf: array of suinfo_update
* @supsz: byte size of suinfo_update
* @nsup: size of suinfo_update array
*
* Description: Takes an array of nilfs_suinfo_update structs and updates
* segment usage accordingly. Only the fields indicated by the sup_flags
* are updated.
*
* Return Value: On success, 0 is returned. On error, one of the
* following negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*
* %-EINVAL - Invalid values in input (segment number, flags or nblocks)
*/
ssize_t nilfs_sufile_set_suinfo(struct inode *sufile, void *buf,
unsigned supsz, size_t nsup)
{
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
struct buffer_head *header_bh, *bh;
struct nilfs_suinfo_update *sup, *supend = buf + supsz * nsup;
struct nilfs_segment_usage *su;
void *kaddr;
unsigned long blkoff, prev_blkoff;
int cleansi, cleansu, dirtysi, dirtysu;
long ncleaned = 0, ndirtied = 0;
int ret = 0;
if (unlikely(nsup == 0))
return ret;
for (sup = buf; sup < supend; sup = (void *)sup + supsz) {
if (sup->sup_segnum >= nilfs->ns_nsegments
|| (sup->sup_flags &
(~0UL << __NR_NILFS_SUINFO_UPDATE_FIELDS))
|| (nilfs_suinfo_update_nblocks(sup) &&
sup->sup_sui.sui_nblocks >
nilfs->ns_blocks_per_segment))
return -EINVAL;
}
down_write(&NILFS_MDT(sufile)->mi_sem);
ret = nilfs_sufile_get_header_block(sufile, &header_bh);
if (ret < 0)
goto out_sem;
sup = buf;
blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
if (ret < 0)
goto out_header;
for (;;) {
kaddr = kmap_atomic(bh->b_page);
su = nilfs_sufile_block_get_segment_usage(
sufile, sup->sup_segnum, bh, kaddr);
if (nilfs_suinfo_update_lastmod(sup))
su->su_lastmod = cpu_to_le64(sup->sup_sui.sui_lastmod);
if (nilfs_suinfo_update_nblocks(sup))
su->su_nblocks = cpu_to_le32(sup->sup_sui.sui_nblocks);
if (nilfs_suinfo_update_flags(sup)) {
/*
* Active flag is a virtual flag projected by running
* nilfs kernel code - drop it not to write it to
* disk.
*/
sup->sup_sui.sui_flags &=
~(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
cleansi = nilfs_suinfo_clean(&sup->sup_sui);
cleansu = nilfs_segment_usage_clean(su);
dirtysi = nilfs_suinfo_dirty(&sup->sup_sui);
dirtysu = nilfs_segment_usage_dirty(su);
if (cleansi && !cleansu)
++ncleaned;
else if (!cleansi && cleansu)
--ncleaned;
if (dirtysi && !dirtysu)
++ndirtied;
else if (!dirtysi && dirtysu)
--ndirtied;
su->su_flags = cpu_to_le32(sup->sup_sui.sui_flags);
}
kunmap_atomic(kaddr);
sup = (void *)sup + supsz;
if (sup >= supend)
break;
prev_blkoff = blkoff;
blkoff = nilfs_sufile_get_blkoff(sufile, sup->sup_segnum);
if (blkoff == prev_blkoff)
continue;
/* get different block */
mark_buffer_dirty(bh);
put_bh(bh);
ret = nilfs_mdt_get_block(sufile, blkoff, 1, NULL, &bh);
if (unlikely(ret < 0))
goto out_mark;
}
mark_buffer_dirty(bh);
put_bh(bh);
out_mark:
if (ncleaned || ndirtied) {
nilfs_sufile_mod_counter(header_bh, (u64)ncleaned,
(u64)ndirtied);
NILFS_SUI(sufile)->ncleansegs += ncleaned;
}
nilfs_mdt_mark_dirty(sufile);
out_header:
put_bh(header_bh);
out_sem:
up_write(&NILFS_MDT(sufile)->mi_sem);
return ret;
}
/**
* nilfs_sufile_trim_fs() - trim ioctl handle function
* @sufile: inode of segment usage file
* @range: fstrim_range structure
*
* start: First Byte to trim
* len: number of Bytes to trim from start
* minlen: minimum extent length in Bytes
*
* Decription: nilfs_sufile_trim_fs goes through all segments containing bytes
* from start to start+len. start is rounded up to the next block boundary
* and start+len is rounded down. For each clean segment blkdev_issue_discard
* function is invoked.
*
* Return Value: On success, 0 is returned or negative error code, otherwise.
*/
int nilfs_sufile_trim_fs(struct inode *sufile, struct fstrim_range *range)
{
struct the_nilfs *nilfs = sufile->i_sb->s_fs_info;
struct buffer_head *su_bh;
struct nilfs_segment_usage *su;
void *kaddr;
size_t n, i, susz = NILFS_MDT(sufile)->mi_entry_size;
sector_t seg_start, seg_end, start_block, end_block;
sector_t start = 0, nblocks = 0;
u64 segnum, segnum_end, minlen, len, max_blocks, ndiscarded = 0;
int ret = 0;
unsigned int sects_per_block;
sects_per_block = (1 << nilfs->ns_blocksize_bits) /
bdev_logical_block_size(nilfs->ns_bdev);
len = range->len >> nilfs->ns_blocksize_bits;
minlen = range->minlen >> nilfs->ns_blocksize_bits;
max_blocks = ((u64)nilfs->ns_nsegments * nilfs->ns_blocks_per_segment);
if (!len || range->start >= max_blocks << nilfs->ns_blocksize_bits)
return -EINVAL;
start_block = (range->start + nilfs->ns_blocksize - 1) >>
nilfs->ns_blocksize_bits;
/*
* range->len can be very large (actually, it is set to
* ULLONG_MAX by default) - truncate upper end of the range
* carefully so as not to overflow.
*/
if (max_blocks - start_block < len)
end_block = max_blocks - 1;
else
end_block = start_block + len - 1;
segnum = nilfs_get_segnum_of_block(nilfs, start_block);
segnum_end = nilfs_get_segnum_of_block(nilfs, end_block);
down_read(&NILFS_MDT(sufile)->mi_sem);
while (segnum <= segnum_end) {
n = nilfs_sufile_segment_usages_in_block(sufile, segnum,
segnum_end);
ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0,
&su_bh);
if (ret < 0) {
if (ret != -ENOENT)
goto out_sem;
/* hole */
segnum += n;
continue;
}
kaddr = kmap_atomic(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(sufile, segnum,
su_bh, kaddr);
for (i = 0; i < n; ++i, ++segnum, su = (void *)su + susz) {
if (!nilfs_segment_usage_clean(su))
continue;
nilfs_get_segment_range(nilfs, segnum, &seg_start,
&seg_end);
if (!nblocks) {
/* start new extent */
start = seg_start;
nblocks = seg_end - seg_start + 1;
continue;
}
if (start + nblocks == seg_start) {
/* add to previous extent */
nblocks += seg_end - seg_start + 1;
continue;
}
/* discard previous extent */
if (start < start_block) {
nblocks -= start_block - start;
start = start_block;
}
if (nblocks >= minlen) {
kunmap_atomic(kaddr);
ret = blkdev_issue_discard(nilfs->ns_bdev,
start * sects_per_block,
nblocks * sects_per_block,
GFP_NOFS, 0);
if (ret < 0) {
put_bh(su_bh);
goto out_sem;
}
ndiscarded += nblocks;
kaddr = kmap_atomic(su_bh->b_page);
su = nilfs_sufile_block_get_segment_usage(
sufile, segnum, su_bh, kaddr);
}
/* start new extent */
start = seg_start;
nblocks = seg_end - seg_start + 1;
}
kunmap_atomic(kaddr);
put_bh(su_bh);
}
if (nblocks) {
/* discard last extent */
if (start < start_block) {
nblocks -= start_block - start;
start = start_block;
}
if (start + nblocks > end_block + 1)
nblocks = end_block - start + 1;
if (nblocks >= minlen) {
ret = blkdev_issue_discard(nilfs->ns_bdev,
start * sects_per_block,
nblocks * sects_per_block,
GFP_NOFS, 0);
if (!ret)
ndiscarded += nblocks;
}
}
out_sem:
up_read(&NILFS_MDT(sufile)->mi_sem);
range->len = ndiscarded << nilfs->ns_blocksize_bits;
return ret;
}
/**
* nilfs_sufile_read - read or get sufile inode
* @sb: super block instance
* @susize: size of a segment usage entry
* @raw_inode: on-disk sufile inode
* @inodep: buffer to store the inode
*/
int nilfs_sufile_read(struct super_block *sb, size_t susize,
struct nilfs_inode *raw_inode, struct inode **inodep)
{
struct inode *sufile;
struct nilfs_sufile_info *sui;
struct buffer_head *header_bh;
struct nilfs_sufile_header *header;
void *kaddr;
int err;
if (susize > sb->s_blocksize) {
printk(KERN_ERR
"NILFS: too large segment usage size: %zu bytes.\n",
susize);
return -EINVAL;
} else if (susize < NILFS_MIN_SEGMENT_USAGE_SIZE) {
printk(KERN_ERR
"NILFS: too small segment usage size: %zu bytes.\n",
susize);
return -EINVAL;
}
sufile = nilfs_iget_locked(sb, NULL, NILFS_SUFILE_INO);
if (unlikely(!sufile))
return -ENOMEM;
if (!(sufile->i_state & I_NEW))
goto out;
err = nilfs_mdt_init(sufile, NILFS_MDT_GFP, sizeof(*sui));
if (err)
goto failed;
nilfs_mdt_set_entry_size(sufile, susize,
sizeof(struct nilfs_sufile_header));
err = nilfs_read_inode_common(sufile, raw_inode);
if (err)
goto failed;
err = nilfs_sufile_get_header_block(sufile, &header_bh);
if (err)
goto failed;
sui = NILFS_SUI(sufile);
kaddr = kmap_atomic(header_bh->b_page);
header = kaddr + bh_offset(header_bh);
sui->ncleansegs = le64_to_cpu(header->sh_ncleansegs);
kunmap_atomic(kaddr);
brelse(header_bh);
sui->allocmax = nilfs_sufile_get_nsegments(sufile) - 1;
sui->allocmin = 0;
unlock_new_inode(sufile);
out:
*inodep = sufile;
return 0;
failed:
iget_failed(sufile);
return err;
}