OpenE2K/linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
b83156b52d
linux/fs/ubifs/super.c
Christoph Hellwig a9185b41a4 pass writeback_control to ->write_inode 
This gives the filesystem more information about the writeback that
is happening.  Trond requested this for the NFS unstable write handling,
and other filesystems might benefit from this too by beeing able to
distinguish between the different callers in more detail.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 13:25:52 -05:00

2227 lines
58 KiB
C
Raw Blame History

/*
* This file is part of UBIFS.
*
* Copyright (C) 2006-2008 Nokia Corporation.
*
* 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 License along with
* this program; if not, write to the Free Software Foundation, Inc., 51
* Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* Authors: Artem Bityutskiy (Битюцкий Артём)
* Adrian Hunter
*/
/*
* This file implements UBIFS initialization and VFS superblock operations. Some
* initialization stuff which is rather large and complex is placed at
* corresponding subsystems, but most of it is here.
*/
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/kthread.h>
#include <linux/parser.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <linux/math64.h>
#include <linux/writeback.h>
#include "ubifs.h"
/*
* Maximum amount of memory we may 'kmalloc()' without worrying that we are
* allocating too much.
*/
#define UBIFS_KMALLOC_OK (128*1024)
/* Slab cache for UBIFS inodes */
struct kmem_cache *ubifs_inode_slab;
/* UBIFS TNC shrinker description */
static struct shrinker ubifs_shrinker_info = {
.shrink = ubifs_shrinker,
.seeks = DEFAULT_SEEKS,
};
/**
* validate_inode - validate inode.
* @c: UBIFS file-system description object
* @inode: the inode to validate
*
* This is a helper function for 'ubifs_iget()' which validates various fields
* of a newly built inode to make sure they contain sane values and prevent
* possible vulnerabilities. Returns zero if the inode is all right and
* a non-zero error code if not.
*/
static int validate_inode(struct ubifs_info *c, const struct inode *inode)
{
int err;
const struct ubifs_inode *ui = ubifs_inode(inode);
if (inode->i_size > c->max_inode_sz) {
ubifs_err("inode is too large (%lld)",
(long long)inode->i_size);
return 1;
}
if (ui->compr_type < 0 || ui->compr_type >= UBIFS_COMPR_TYPES_CNT) {
ubifs_err("unknown compression type %d", ui->compr_type);
return 2;
}
if (ui->xattr_names + ui->xattr_cnt > XATTR_LIST_MAX)
return 3;
if (ui->data_len < 0 || ui->data_len > UBIFS_MAX_INO_DATA)
return 4;
if (ui->xattr && (inode->i_mode & S_IFMT) != S_IFREG)
return 5;
if (!ubifs_compr_present(ui->compr_type)) {
ubifs_warn("inode %lu uses '%s' compression, but it was not "
"compiled in", inode->i_ino,
ubifs_compr_name(ui->compr_type));
}
err = dbg_check_dir_size(c, inode);
return err;
}
struct inode *ubifs_iget(struct super_block *sb, unsigned long inum)
{
int err;
union ubifs_key key;
struct ubifs_ino_node *ino;
struct ubifs_info *c = sb->s_fs_info;
struct inode *inode;
struct ubifs_inode *ui;
dbg_gen("inode %lu", inum);
inode = iget_locked(sb, inum);
if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
ui = ubifs_inode(inode);
ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
if (!ino) {
err = -ENOMEM;
goto out;
}
ino_key_init(c, &key, inode->i_ino);
err = ubifs_tnc_lookup(c, &key, ino);
if (err)
goto out_ino;
inode->i_flags |= (S_NOCMTIME | S_NOATIME);
inode->i_nlink = le32_to_cpu(ino->nlink);
inode->i_uid = le32_to_cpu(ino->uid);
inode->i_gid = le32_to_cpu(ino->gid);
inode->i_atime.tv_sec = (int64_t)le64_to_cpu(ino->atime_sec);
inode->i_atime.tv_nsec = le32_to_cpu(ino->atime_nsec);
inode->i_mtime.tv_sec = (int64_t)le64_to_cpu(ino->mtime_sec);
inode->i_mtime.tv_nsec = le32_to_cpu(ino->mtime_nsec);
inode->i_ctime.tv_sec = (int64_t)le64_to_cpu(ino->ctime_sec);
inode->i_ctime.tv_nsec = le32_to_cpu(ino->ctime_nsec);
inode->i_mode = le32_to_cpu(ino->mode);
inode->i_size = le64_to_cpu(ino->size);
ui->data_len = le32_to_cpu(ino->data_len);
ui->flags = le32_to_cpu(ino->flags);
ui->compr_type = le16_to_cpu(ino->compr_type);
ui->creat_sqnum = le64_to_cpu(ino->creat_sqnum);
ui->xattr_cnt = le32_to_cpu(ino->xattr_cnt);
ui->xattr_size = le32_to_cpu(ino->xattr_size);
ui->xattr_names = le32_to_cpu(ino->xattr_names);
ui->synced_i_size = ui->ui_size = inode->i_size;
ui->xattr = (ui->flags & UBIFS_XATTR_FL) ? 1 : 0;
err = validate_inode(c, inode);
if (err)
goto out_invalid;
/* Disable read-ahead */
inode->i_mapping->backing_dev_info = &c->bdi;
switch (inode->i_mode & S_IFMT) {
case S_IFREG:
inode->i_mapping->a_ops = &ubifs_file_address_operations;
inode->i_op = &ubifs_file_inode_operations;
inode->i_fop = &ubifs_file_operations;
if (ui->xattr) {
ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
if (!ui->data) {
err = -ENOMEM;
goto out_ino;
}
memcpy(ui->data, ino->data, ui->data_len);
((char *)ui->data)[ui->data_len] = '\0';
} else if (ui->data_len != 0) {
err = 10;
goto out_invalid;
}
break;
case S_IFDIR:
inode->i_op = &ubifs_dir_inode_operations;
inode->i_fop = &ubifs_dir_operations;
if (ui->data_len != 0) {
err = 11;
goto out_invalid;
}
break;
case S_IFLNK:
inode->i_op = &ubifs_symlink_inode_operations;
if (ui->data_len <= 0 || ui->data_len > UBIFS_MAX_INO_DATA) {
err = 12;
goto out_invalid;
}
ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
if (!ui->data) {
err = -ENOMEM;
goto out_ino;
}
memcpy(ui->data, ino->data, ui->data_len);
((char *)ui->data)[ui->data_len] = '\0';
break;
case S_IFBLK:
case S_IFCHR:
{
dev_t rdev;
union ubifs_dev_desc *dev;
ui->data = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
if (!ui->data) {
err = -ENOMEM;
goto out_ino;
}
dev = (union ubifs_dev_desc *)ino->data;
if (ui->data_len == sizeof(dev->new))
rdev = new_decode_dev(le32_to_cpu(dev->new));
else if (ui->data_len == sizeof(dev->huge))
rdev = huge_decode_dev(le64_to_cpu(dev->huge));
else {
err = 13;
goto out_invalid;
}
memcpy(ui->data, ino->data, ui->data_len);
inode->i_op = &ubifs_file_inode_operations;
init_special_inode(inode, inode->i_mode, rdev);
break;
}
case S_IFSOCK:
case S_IFIFO:
inode->i_op = &ubifs_file_inode_operations;
init_special_inode(inode, inode->i_mode, 0);
if (ui->data_len != 0) {
err = 14;
goto out_invalid;
}
break;
default:
err = 15;
goto out_invalid;
}
kfree(ino);
ubifs_set_inode_flags(inode);
unlock_new_inode(inode);
return inode;
out_invalid:
ubifs_err("inode %lu validation failed, error %d", inode->i_ino, err);
dbg_dump_node(c, ino);
dbg_dump_inode(c, inode);
err = -EINVAL;
out_ino:
kfree(ino);
out:
ubifs_err("failed to read inode %lu, error %d", inode->i_ino, err);
iget_failed(inode);
return ERR_PTR(err);
}
static struct inode *ubifs_alloc_inode(struct super_block *sb)
{
struct ubifs_inode *ui;
ui = kmem_cache_alloc(ubifs_inode_slab, GFP_NOFS);
if (!ui)
return NULL;
memset((void *)ui + sizeof(struct inode), 0,
sizeof(struct ubifs_inode) - sizeof(struct inode));
mutex_init(&ui->ui_mutex);
spin_lock_init(&ui->ui_lock);
return &ui->vfs_inode;
};
static void ubifs_destroy_inode(struct inode *inode)
{
struct ubifs_inode *ui = ubifs_inode(inode);
kfree(ui->data);
kmem_cache_free(ubifs_inode_slab, inode);
}
/*
* Note, Linux write-back code calls this without 'i_mutex'.
*/
static int ubifs_write_inode(struct inode *inode, struct writeback_control *wbc)
{
int err = 0;
struct ubifs_info *c = inode->i_sb->s_fs_info;
struct ubifs_inode *ui = ubifs_inode(inode);
ubifs_assert(!ui->xattr);
if (is_bad_inode(inode))
return 0;
mutex_lock(&ui->ui_mutex);
/*
* Due to races between write-back forced by budgeting
* (see 'sync_some_inodes()') and pdflush write-back, the inode may
* have already been synchronized, do not do this again. This might
* also happen if it was synchronized in an VFS operation, e.g.
* 'ubifs_link()'.
*/
if (!ui->dirty) {
mutex_unlock(&ui->ui_mutex);
return 0;
}
/*
* As an optimization, do not write orphan inodes to the media just
* because this is not needed.
*/
dbg_gen("inode %lu, mode %#x, nlink %u",
inode->i_ino, (int)inode->i_mode, inode->i_nlink);
if (inode->i_nlink) {
err = ubifs_jnl_write_inode(c, inode);
if (err)
ubifs_err("can't write inode %lu, error %d",
inode->i_ino, err);
else
err = dbg_check_inode_size(c, inode, ui->ui_size);
}
ui->dirty = 0;
mutex_unlock(&ui->ui_mutex);
ubifs_release_dirty_inode_budget(c, ui);
return err;
}
static void ubifs_delete_inode(struct inode *inode)
{
int err;
struct ubifs_info *c = inode->i_sb->s_fs_info;
struct ubifs_inode *ui = ubifs_inode(inode);
if (ui->xattr)
/*
* Extended attribute inode deletions are fully handled in
* 'ubifs_removexattr()'. These inodes are special and have
* limited usage, so there is nothing to do here.
*/
goto out;
dbg_gen("inode %lu, mode %#x", inode->i_ino, (int)inode->i_mode);
ubifs_assert(!atomic_read(&inode->i_count));
ubifs_assert(inode->i_nlink == 0);
truncate_inode_pages(&inode->i_data, 0);
if (is_bad_inode(inode))
goto out;
ui->ui_size = inode->i_size = 0;
err = ubifs_jnl_delete_inode(c, inode);
if (err)
/*
* Worst case we have a lost orphan inode wasting space, so a
* simple error message is OK here.
*/
ubifs_err("can't delete inode %lu, error %d",
inode->i_ino, err);
out:
if (ui->dirty)
ubifs_release_dirty_inode_budget(c, ui);
else {
/* We've deleted something - clean the "no space" flags */
c->nospace = c->nospace_rp = 0;
smp_wmb();
}
clear_inode(inode);
}
static void ubifs_dirty_inode(struct inode *inode)
{
struct ubifs_inode *ui = ubifs_inode(inode);
ubifs_assert(mutex_is_locked(&ui->ui_mutex));
if (!ui->dirty) {
ui->dirty = 1;
dbg_gen("inode %lu", inode->i_ino);
}
}
static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct ubifs_info *c = dentry->d_sb->s_fs_info;
unsigned long long free;
__le32 *uuid = (__le32 *)c->uuid;
free = ubifs_get_free_space(c);
dbg_gen("free space %lld bytes (%lld blocks)",
free, free >> UBIFS_BLOCK_SHIFT);
buf->f_type = UBIFS_SUPER_MAGIC;
buf->f_bsize = UBIFS_BLOCK_SIZE;
buf->f_blocks = c->block_cnt;
buf->f_bfree = free >> UBIFS_BLOCK_SHIFT;
if (free > c->report_rp_size)
buf->f_bavail = (free - c->report_rp_size) >> UBIFS_BLOCK_SHIFT;
else
buf->f_bavail = 0;
buf->f_files = 0;
buf->f_ffree = 0;
buf->f_namelen = UBIFS_MAX_NLEN;
buf->f_fsid.val[0] = le32_to_cpu(uuid[0]) ^ le32_to_cpu(uuid[2]);
buf->f_fsid.val[1] = le32_to_cpu(uuid[1]) ^ le32_to_cpu(uuid[3]);
ubifs_assert(buf->f_bfree <= c->block_cnt);
return 0;
}
static int ubifs_show_options(struct seq_file *s, struct vfsmount *mnt)
{
struct ubifs_info *c = mnt->mnt_sb->s_fs_info;
if (c->mount_opts.unmount_mode == 2)
seq_printf(s, ",fast_unmount");
else if (c->mount_opts.unmount_mode == 1)
seq_printf(s, ",norm_unmount");
if (c->mount_opts.bulk_read == 2)
seq_printf(s, ",bulk_read");
else if (c->mount_opts.bulk_read == 1)
seq_printf(s, ",no_bulk_read");
if (c->mount_opts.chk_data_crc == 2)
seq_printf(s, ",chk_data_crc");
else if (c->mount_opts.chk_data_crc == 1)
seq_printf(s, ",no_chk_data_crc");
if (c->mount_opts.override_compr) {
seq_printf(s, ",compr=%s",
ubifs_compr_name(c->mount_opts.compr_type));
}
return 0;
}
static int ubifs_sync_fs(struct super_block *sb, int wait)
{
int i, err;
struct ubifs_info *c = sb->s_fs_info;
/*
* Zero @wait is just an advisory thing to help the file system shove
* lots of data into the queues, and there will be the second
* '->sync_fs()' call, with non-zero @wait.
*/
if (!wait)
return 0;
/*
* Synchronize write buffers, because 'ubifs_run_commit()' does not
* do this if it waits for an already running commit.
*/
for (i = 0; i < c->jhead_cnt; i++) {
err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
if (err)
return err;
}
/*
* Strictly speaking, it is not necessary to commit the journal here,
* synchronizing write-buffers would be enough. But committing makes
* UBIFS free space predictions much more accurate, so we want to let
* the user be able to get more accurate results of 'statfs()' after
* they synchronize the file system.
*/
err = ubifs_run_commit(c);
if (err)
return err;
return ubi_sync(c->vi.ubi_num);
}
/**
* init_constants_early - initialize UBIFS constants.
* @c: UBIFS file-system description object
*
* This function initialize UBIFS constants which do not need the superblock to
* be read. It also checks that the UBI volume satisfies basic UBIFS
* requirements. Returns zero in case of success and a negative error code in
* case of failure.
*/
static int init_constants_early(struct ubifs_info *c)
{
if (c->vi.corrupted) {
ubifs_warn("UBI volume is corrupted - read-only mode");
c->ro_media = 1;
}
if (c->di.ro_mode) {
ubifs_msg("read-only UBI device");
c->ro_media = 1;
}
if (c->vi.vol_type == UBI_STATIC_VOLUME) {
ubifs_msg("static UBI volume - read-only mode");
c->ro_media = 1;
}
c->leb_cnt = c->vi.size;
c->leb_size = c->vi.usable_leb_size;
c->half_leb_size = c->leb_size / 2;
c->min_io_size = c->di.min_io_size;
c->min_io_shift = fls(c->min_io_size) - 1;
if (c->leb_size < UBIFS_MIN_LEB_SZ) {
ubifs_err("too small LEBs (%d bytes), min. is %d bytes",
c->leb_size, UBIFS_MIN_LEB_SZ);
return -EINVAL;
}
if (c->leb_cnt < UBIFS_MIN_LEB_CNT) {
ubifs_err("too few LEBs (%d), min. is %d",
c->leb_cnt, UBIFS_MIN_LEB_CNT);
return -EINVAL;
}
if (!is_power_of_2(c->min_io_size)) {
ubifs_err("bad min. I/O size %d", c->min_io_size);
return -EINVAL;
}
/*
* UBIFS aligns all node to 8-byte boundary, so to make function in
* io.c simpler, assume minimum I/O unit size to be 8 bytes if it is
* less than 8.
*/
if (c->min_io_size < 8) {
c->min_io_size = 8;
c->min_io_shift = 3;
}
c->ref_node_alsz = ALIGN(UBIFS_REF_NODE_SZ, c->min_io_size);
c->mst_node_alsz = ALIGN(UBIFS_MST_NODE_SZ, c->min_io_size);
/*
* Initialize node length ranges which are mostly needed for node
* length validation.
*/
c->ranges[UBIFS_PAD_NODE].len = UBIFS_PAD_NODE_SZ;
c->ranges[UBIFS_SB_NODE].len = UBIFS_SB_NODE_SZ;
c->ranges[UBIFS_MST_NODE].len = UBIFS_MST_NODE_SZ;
c->ranges[UBIFS_REF_NODE].len = UBIFS_REF_NODE_SZ;
c->ranges[UBIFS_TRUN_NODE].len = UBIFS_TRUN_NODE_SZ;
c->ranges[UBIFS_CS_NODE].len = UBIFS_CS_NODE_SZ;
c->ranges[UBIFS_INO_NODE].min_len = UBIFS_INO_NODE_SZ;
c->ranges[UBIFS_INO_NODE].max_len = UBIFS_MAX_INO_NODE_SZ;
c->ranges[UBIFS_ORPH_NODE].min_len =
UBIFS_ORPH_NODE_SZ + sizeof(__le64);
c->ranges[UBIFS_ORPH_NODE].max_len = c->leb_size;
c->ranges[UBIFS_DENT_NODE].min_len = UBIFS_DENT_NODE_SZ;
c->ranges[UBIFS_DENT_NODE].max_len = UBIFS_MAX_DENT_NODE_SZ;
c->ranges[UBIFS_XENT_NODE].min_len = UBIFS_XENT_NODE_SZ;
c->ranges[UBIFS_XENT_NODE].max_len = UBIFS_MAX_XENT_NODE_SZ;
c->ranges[UBIFS_DATA_NODE].min_len = UBIFS_DATA_NODE_SZ;
c->ranges[UBIFS_DATA_NODE].max_len = UBIFS_MAX_DATA_NODE_SZ;
/*
* Minimum indexing node size is amended later when superblock is
* read and the key length is known.
*/
c->ranges[UBIFS_IDX_NODE].min_len = UBIFS_IDX_NODE_SZ + UBIFS_BRANCH_SZ;
/*
* Maximum indexing node size is amended later when superblock is
* read and the fanout is known.
*/
c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX;
/*
* Initialize dead and dark LEB space watermarks. See gc.c for comments
* about these values.
*/
c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size);
c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size);
/*
* Calculate how many bytes would be wasted at the end of LEB if it was
* fully filled with data nodes of maximum size. This is used in
* calculations when reporting free space.
*/
c->leb_overhead = c->leb_size % UBIFS_MAX_DATA_NODE_SZ;
/* Buffer size for bulk-reads */
c->max_bu_buf_len = UBIFS_MAX_BULK_READ * UBIFS_MAX_DATA_NODE_SZ;
if (c->max_bu_buf_len > c->leb_size)
c->max_bu_buf_len = c->leb_size;
return 0;
}
/**
* bud_wbuf_callback - bud LEB write-buffer synchronization call-back.
* @c: UBIFS file-system description object
* @lnum: LEB the write-buffer was synchronized to
* @free: how many free bytes left in this LEB
* @pad: how many bytes were padded
*
* This is a callback function which is called by the I/O unit when the
* write-buffer is synchronized. We need this to correctly maintain space
* accounting in bud logical eraseblocks. This function returns zero in case of
* success and a negative error code in case of failure.
*
* This function actually belongs to the journal, but we keep it here because
* we want to keep it static.
*/
static int bud_wbuf_callback(struct ubifs_info *c, int lnum, int free, int pad)
{
return ubifs_update_one_lp(c, lnum, free, pad, 0, 0);
}
/*
* init_constants_sb - initialize UBIFS constants.
* @c: UBIFS file-system description object
*
* This is a helper function which initializes various UBIFS constants after
* the superblock has been read. It also checks various UBIFS parameters and
* makes sure they are all right. Returns zero in case of success and a
* negative error code in case of failure.
*/
static int init_constants_sb(struct ubifs_info *c)
{
int tmp, err;
long long tmp64;
c->main_bytes = (long long)c->main_lebs * c->leb_size;
c->max_znode_sz = sizeof(struct ubifs_znode) +
c->fanout * sizeof(struct ubifs_zbranch);
tmp = ubifs_idx_node_sz(c, 1);
c->ranges[UBIFS_IDX_NODE].min_len = tmp;
c->min_idx_node_sz = ALIGN(tmp, 8);
tmp = ubifs_idx_node_sz(c, c->fanout);
c->ranges[UBIFS_IDX_NODE].max_len = tmp;
c->max_idx_node_sz = ALIGN(tmp, 8);
/* Make sure LEB size is large enough to fit full commit */
tmp = UBIFS_CS_NODE_SZ + UBIFS_REF_NODE_SZ * c->jhead_cnt;
tmp = ALIGN(tmp, c->min_io_size);
if (tmp > c->leb_size) {
dbg_err("too small LEB size %d, at least %d needed",
c->leb_size, tmp);
return -EINVAL;
}
/*
* Make sure that the log is large enough to fit reference nodes for
* all buds plus one reserved LEB.
*/
tmp64 = c->max_bud_bytes + c->leb_size - 1;
c->max_bud_cnt = div_u64(tmp64, c->leb_size);
tmp = (c->ref_node_alsz * c->max_bud_cnt + c->leb_size - 1);
tmp /= c->leb_size;
tmp += 1;
if (c->log_lebs < tmp) {
dbg_err("too small log %d LEBs, required min. %d LEBs",
c->log_lebs, tmp);
return -EINVAL;
}
/*
* When budgeting we assume worst-case scenarios when the pages are not
* be compressed and direntries are of the maximum size.
*
* Note, data, which may be stored in inodes is budgeted separately, so
* it is not included into 'c->inode_budget'.
*/
c->page_budget = UBIFS_MAX_DATA_NODE_SZ * UBIFS_BLOCKS_PER_PAGE;
c->inode_budget = UBIFS_INO_NODE_SZ;
c->dent_budget = UBIFS_MAX_DENT_NODE_SZ;
/*
* When the amount of flash space used by buds becomes
* 'c->max_bud_bytes', UBIFS just blocks all writers and starts commit.
* The writers are unblocked when the commit is finished. To avoid
* writers to be blocked UBIFS initiates background commit in advance,
* when number of bud bytes becomes above the limit defined below.
*/
c->bg_bud_bytes = (c->max_bud_bytes * 13) >> 4;
/*
* Ensure minimum journal size. All the bytes in the journal heads are
* considered to be used, when calculating the current journal usage.
* Consequently, if the journal is too small, UBIFS will treat it as
* always full.
*/
tmp64 = (long long)(c->jhead_cnt + 1) * c->leb_size + 1;
if (c->bg_bud_bytes < tmp64)
c->bg_bud_bytes = tmp64;
if (c->max_bud_bytes < tmp64 + c->leb_size)
c->max_bud_bytes = tmp64 + c->leb_size;
err = ubifs_calc_lpt_geom(c);
if (err)
return err;
/* Initialize effective LEB size used in budgeting calculations */
c->idx_leb_size = c->leb_size - c->max_idx_node_sz;
return 0;
}
/*
* init_constants_master - initialize UBIFS constants.
* @c: UBIFS file-system description object
*
* This is a helper function which initializes various UBIFS constants after
* the master node has been read. It also checks various UBIFS parameters and
* makes sure they are all right.
*/
static void init_constants_master(struct ubifs_info *c)
{
long long tmp64;
c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
c->report_rp_size = ubifs_reported_space(c, c->rp_size);
/*
* Calculate total amount of FS blocks. This number is not used
* internally because it does not make much sense for UBIFS, but it is
* necessary to report something for the 'statfs()' call.
*
* Subtract the LEB reserved for GC, the LEB which is reserved for
* deletions, minimum LEBs for the index, and assume only one journal
* head is available.
*/
tmp64 = c->main_lebs - 1 - 1 - MIN_INDEX_LEBS - c->jhead_cnt + 1;
tmp64 *= (long long)c->leb_size - c->leb_overhead;
tmp64 = ubifs_reported_space(c, tmp64);
c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT;
}
/**
* take_gc_lnum - reserve GC LEB.
* @c: UBIFS file-system description object
*
* This function ensures that the LEB reserved for garbage collection is marked
* as "taken" in lprops. We also have to set free space to LEB size and dirty
* space to zero, because lprops may contain out-of-date information if the
* file-system was un-mounted before it has been committed. This function
* returns zero in case of success and a negative error code in case of
* failure.
*/
static int take_gc_lnum(struct ubifs_info *c)
{
int err;
if (c->gc_lnum == -1) {
ubifs_err("no LEB for GC");
return -EINVAL;
}
/* And we have to tell lprops that this LEB is taken */
err = ubifs_change_one_lp(c, c->gc_lnum, c->leb_size, 0,
LPROPS_TAKEN, 0, 0);
return err;
}
/**
* alloc_wbufs - allocate write-buffers.
* @c: UBIFS file-system description object
*
* This helper function allocates and initializes UBIFS write-buffers. Returns
* zero in case of success and %-ENOMEM in case of failure.
*/
static int alloc_wbufs(struct ubifs_info *c)
{
int i, err;
c->jheads = kzalloc(c->jhead_cnt * sizeof(struct ubifs_jhead),
GFP_KERNEL);
if (!c->jheads)
return -ENOMEM;
/* Initialize journal heads */
for (i = 0; i < c->jhead_cnt; i++) {
INIT_LIST_HEAD(&c->jheads[i].buds_list);
err = ubifs_wbuf_init(c, &c->jheads[i].wbuf);
if (err)
return err;
c->jheads[i].wbuf.sync_callback = &bud_wbuf_callback;
c->jheads[i].wbuf.jhead = i;
}
c->jheads[BASEHD].wbuf.dtype = UBI_SHORTTERM;
/*
* Garbage Collector head likely contains long-term data and
* does not need to be synchronized by timer.
*/
c->jheads[GCHD].wbuf.dtype = UBI_LONGTERM;
c->jheads[GCHD].wbuf.no_timer = 1;
return 0;
}
/**
* free_wbufs - free write-buffers.
* @c: UBIFS file-system description object
*/
static void free_wbufs(struct ubifs_info *c)
{
int i;
if (c->jheads) {
for (i = 0; i < c->jhead_cnt; i++) {
kfree(c->jheads[i].wbuf.buf);
kfree(c->jheads[i].wbuf.inodes);
}
kfree(c->jheads);
c->jheads = NULL;
}
}
/**
* free_orphans - free orphans.
* @c: UBIFS file-system description object
*/
static void free_orphans(struct ubifs_info *c)
{
struct ubifs_orphan *orph;
while (c->orph_dnext) {
orph = c->orph_dnext;
c->orph_dnext = orph->dnext;
list_del(&orph->list);
kfree(orph);
}
while (!list_empty(&c->orph_list)) {
orph = list_entry(c->orph_list.next, struct ubifs_orphan, list);
list_del(&orph->list);
kfree(orph);
dbg_err("orphan list not empty at unmount");
}
vfree(c->orph_buf);
c->orph_buf = NULL;
}
/**
* free_buds - free per-bud objects.
* @c: UBIFS file-system description object
*/
static void free_buds(struct ubifs_info *c)
{
struct rb_node *this = c->buds.rb_node;
struct ubifs_bud *bud;
while (this) {
if (this->rb_left)
this = this->rb_left;
else if (this->rb_right)
this = this->rb_right;
else {
bud = rb_entry(this, struct ubifs_bud, rb);
this = rb_parent(this);
if (this) {
if (this->rb_left == &bud->rb)
this->rb_left = NULL;
else
this->rb_right = NULL;
}
kfree(bud);
}
}
}
/**
* check_volume_empty - check if the UBI volume is empty.
* @c: UBIFS file-system description object
*
* This function checks if the UBIFS volume is empty by looking if its LEBs are
* mapped or not. The result of checking is stored in the @c->empty variable.
* Returns zero in case of success and a negative error code in case of
* failure.
*/
static int check_volume_empty(struct ubifs_info *c)
{
int lnum, err;
c->empty = 1;
for (lnum = 0; lnum < c->leb_cnt; lnum++) {
err = ubi_is_mapped(c->ubi, lnum);
if (unlikely(err < 0))
return err;
if (err == 1) {
c->empty = 0;
break;
}
cond_resched();
}
return 0;
}
/*
* UBIFS mount options.
*
* Opt_fast_unmount: do not run a journal commit before un-mounting
* Opt_norm_unmount: run a journal commit before un-mounting
* Opt_bulk_read: enable bulk-reads
* Opt_no_bulk_read: disable bulk-reads
* Opt_chk_data_crc: check CRCs when reading data nodes
* Opt_no_chk_data_crc: do not check CRCs when reading data nodes
* Opt_override_compr: override default compressor
* Opt_err: just end of array marker
*/
enum {
Opt_fast_unmount,
Opt_norm_unmount,
Opt_bulk_read,
Opt_no_bulk_read,
Opt_chk_data_crc,
Opt_no_chk_data_crc,
Opt_override_compr,
Opt_err,
};
static const match_table_t tokens = {
{Opt_fast_unmount, "fast_unmount"},
{Opt_norm_unmount, "norm_unmount"},
{Opt_bulk_read, "bulk_read"},
{Opt_no_bulk_read, "no_bulk_read"},
{Opt_chk_data_crc, "chk_data_crc"},
{Opt_no_chk_data_crc, "no_chk_data_crc"},
{Opt_override_compr, "compr=%s"},
{Opt_err, NULL},
};
/**
* parse_standard_option - parse a standard mount option.
* @option: the option to parse
*
* Normally, standard mount options like "sync" are passed to file-systems as
* flags. However, when a "rootflags=" kernel boot parameter is used, they may
* be present in the options string. This function tries to deal with this
* situation and parse standard options. Returns 0 if the option was not
* recognized, and the corresponding integer flag if it was.
*
* UBIFS is only interested in the "sync" option, so do not check for anything
* else.
*/
static int parse_standard_option(const char *option)
{
ubifs_msg("parse %s", option);
if (!strcmp(option, "sync"))
return MS_SYNCHRONOUS;
return 0;
}
/**
* ubifs_parse_options - parse mount parameters.
* @c: UBIFS file-system description object
* @options: parameters to parse
* @is_remount: non-zero if this is FS re-mount
*
* This function parses UBIFS mount options and returns zero in case success
* and a negative error code in case of failure.
*/
static int ubifs_parse_options(struct ubifs_info *c, char *options,
int is_remount)
{
char *p;
substring_t args[MAX_OPT_ARGS];
if (!options)
return 0;
while ((p = strsep(&options, ","))) {
int token;
if (!*p)
continue;
token = match_token(p, tokens, args);
switch (token) {
/*
* %Opt_fast_unmount and %Opt_norm_unmount options are ignored.
* We accept them in order to be backward-compatible. But this
* should be removed at some point.
*/
case Opt_fast_unmount:
c->mount_opts.unmount_mode = 2;
break;
case Opt_norm_unmount:
c->mount_opts.unmount_mode = 1;
break;
case Opt_bulk_read:
c->mount_opts.bulk_read = 2;
c->bulk_read = 1;
break;
case Opt_no_bulk_read:
c->mount_opts.bulk_read = 1;
c->bulk_read = 0;
break;
case Opt_chk_data_crc:
c->mount_opts.chk_data_crc = 2;
c->no_chk_data_crc = 0;
break;
case Opt_no_chk_data_crc:
c->mount_opts.chk_data_crc = 1;
c->no_chk_data_crc = 1;
break;
case Opt_override_compr:
{
char *name = match_strdup(&args[0]);
if (!name)
return -ENOMEM;
if (!strcmp(name, "none"))
c->mount_opts.compr_type = UBIFS_COMPR_NONE;
else if (!strcmp(name, "lzo"))
c->mount_opts.compr_type = UBIFS_COMPR_LZO;
else if (!strcmp(name, "zlib"))
c->mount_opts.compr_type = UBIFS_COMPR_ZLIB;
else {
ubifs_err("unknown compressor \"%s\"", name);
kfree(name);
return -EINVAL;
}
kfree(name);
c->mount_opts.override_compr = 1;
c->default_compr = c->mount_opts.compr_type;
break;
}
default:
{
unsigned long flag;
struct super_block *sb = c->vfs_sb;
flag = parse_standard_option(p);
if (!flag) {
ubifs_err("unrecognized mount option \"%s\" "
"or missing value", p);
return -EINVAL;
}
sb->s_flags |= flag;
break;
}
}
}
return 0;
}
/**
* destroy_journal - destroy journal data structures.
* @c: UBIFS file-system description object
*
* This function destroys journal data structures including those that may have
* been created by recovery functions.
*/
static void destroy_journal(struct ubifs_info *c)
{
while (!list_empty(&c->unclean_leb_list)) {
struct ubifs_unclean_leb *ucleb;
ucleb = list_entry(c->unclean_leb_list.next,
struct ubifs_unclean_leb, list);
list_del(&ucleb->list);
kfree(ucleb);
}
while (!list_empty(&c->old_buds)) {
struct ubifs_bud *bud;
bud = list_entry(c->old_buds.next, struct ubifs_bud, list);
list_del(&bud->list);
kfree(bud);
}
ubifs_destroy_idx_gc(c);
ubifs_destroy_size_tree(c);
ubifs_tnc_close(c);
free_buds(c);
}
/**
* bu_init - initialize bulk-read information.
* @c: UBIFS file-system description object
*/
static void bu_init(struct ubifs_info *c)
{
ubifs_assert(c->bulk_read == 1);
if (c->bu.buf)
return; /* Already initialized */
again:
c->bu.buf = kmalloc(c->max_bu_buf_len, GFP_KERNEL | __GFP_NOWARN);
if (!c->bu.buf) {
if (c->max_bu_buf_len > UBIFS_KMALLOC_OK) {
c->max_bu_buf_len = UBIFS_KMALLOC_OK;
goto again;
}
/* Just disable bulk-read */
ubifs_warn("Cannot allocate %d bytes of memory for bulk-read, "
"disabling it", c->max_bu_buf_len);
c->mount_opts.bulk_read = 1;
c->bulk_read = 0;
return;
}
}
/**
* check_free_space - check if there is enough free space to mount.
* @c: UBIFS file-system description object
*
* This function makes sure UBIFS has enough free space to be mounted in
* read/write mode. UBIFS must always have some free space to allow deletions.
*/
static int check_free_space(struct ubifs_info *c)
{
ubifs_assert(c->dark_wm > 0);
if (c->lst.total_free + c->lst.total_dirty < c->dark_wm) {
ubifs_err("insufficient free space to mount in read/write mode");
dbg_dump_budg(c);
dbg_dump_lprops(c);
return -ENOSPC;
}
return 0;
}
/**
* mount_ubifs - mount UBIFS file-system.
* @c: UBIFS file-system description object
*
* This function mounts UBIFS file system. Returns zero in case of success and
* a negative error code in case of failure.
*
* Note, the function does not de-allocate resources it it fails half way
* through, and the caller has to do this instead.
*/
static int mount_ubifs(struct ubifs_info *c)
{
struct super_block *sb = c->vfs_sb;
int err, mounted_read_only = (sb->s_flags & MS_RDONLY);
long long x;
size_t sz;
err = init_constants_early(c);
if (err)
return err;
err = ubifs_debugging_init(c);
if (err)
return err;
err = check_volume_empty(c);
if (err)
goto out_free;
if (c->empty && (mounted_read_only || c->ro_media)) {
/*
* This UBI volume is empty, and read-only, or the file system
* is mounted read-only - we cannot format it.
*/
ubifs_err("can't format empty UBI volume: read-only %s",
c->ro_media ? "UBI volume" : "mount");
err = -EROFS;
goto out_free;
}
if (c->ro_media && !mounted_read_only) {
ubifs_err("cannot mount read-write - read-only media");
err = -EROFS;
goto out_free;
}
/*
* The requirement for the buffer is that it should fit indexing B-tree
* height amount of integers. We assume the height if the TNC tree will
* never exceed 64.
*/
err = -ENOMEM;
c->bottom_up_buf = kmalloc(BOTTOM_UP_HEIGHT * sizeof(int), GFP_KERNEL);
if (!c->bottom_up_buf)
goto out_free;
c->sbuf = vmalloc(c->leb_size);
if (!c->sbuf)
goto out_free;
if (!mounted_read_only) {
c->ileb_buf = vmalloc(c->leb_size);
if (!c->ileb_buf)
goto out_free;
}
if (c->bulk_read == 1)
bu_init(c);
/*
* We have to check all CRCs, even for data nodes, when we mount the FS
* (specifically, when we are replaying).
*/
c->always_chk_crc = 1;
err = ubifs_read_superblock(c);
if (err)
goto out_free;
/*
* Make sure the compressor which is set as default in the superblock
* or overridden by mount options is actually compiled in.
*/
if (!ubifs_compr_present(c->default_compr)) {
ubifs_err("'compressor \"%s\" is not compiled in",
ubifs_compr_name(c->default_compr));
err = -ENOTSUPP;
goto out_free;
}
err = init_constants_sb(c);
if (err)
goto out_free;
sz = ALIGN(c->max_idx_node_sz, c->min_io_size);
sz = ALIGN(sz + c->max_idx_node_sz, c->min_io_size);
c->cbuf = kmalloc(sz, GFP_NOFS);
if (!c->cbuf) {
err = -ENOMEM;
goto out_free;
}
sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num, c->vi.vol_id);
if (!mounted_read_only) {
err = alloc_wbufs(c);
if (err)
goto out_cbuf;
/* Create background thread */
c->bgt = kthread_create(ubifs_bg_thread, c, "%s", c->bgt_name);
if (IS_ERR(c->bgt)) {
err = PTR_ERR(c->bgt);
c->bgt = NULL;
ubifs_err("cannot spawn \"%s\", error %d",
c->bgt_name, err);
goto out_wbufs;
}
wake_up_process(c->bgt);
}
err = ubifs_read_master(c);
if (err)
goto out_master;
init_constants_master(c);
if ((c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY)) != 0) {
ubifs_msg("recovery needed");
c->need_recovery = 1;
if (!mounted_read_only) {
err = ubifs_recover_inl_heads(c, c->sbuf);
if (err)
goto out_master;
}
} else if (!mounted_read_only) {
/*
* Set the "dirty" flag so that if we reboot uncleanly we
* will notice this immediately on the next mount.
*/
c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
err = ubifs_write_master(c);
if (err)
goto out_master;
}
err = ubifs_lpt_init(c, 1, !mounted_read_only);
if (err)
goto out_lpt;
err = dbg_check_idx_size(c, c->old_idx_sz);
if (err)
goto out_lpt;
err = ubifs_replay_journal(c);
if (err)
goto out_journal;
/* Calculate 'min_idx_lebs' after journal replay */
c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
err = ubifs_mount_orphans(c, c->need_recovery, mounted_read_only);
if (err)
goto out_orphans;
if (!mounted_read_only) {
int lnum;
err = check_free_space(c);
if (err)
goto out_orphans;
/* Check for enough log space */
lnum = c->lhead_lnum + 1;
if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
lnum = UBIFS_LOG_LNUM;
if (lnum == c->ltail_lnum) {
err = ubifs_consolidate_log(c);
if (err)
goto out_orphans;
}
if (c->need_recovery) {
err = ubifs_recover_size(c);
if (err)
goto out_orphans;
err = ubifs_rcvry_gc_commit(c);
} else {
err = take_gc_lnum(c);
if (err)
goto out_orphans;
/*
* GC LEB may contain garbage if there was an unclean
* reboot, and it should be un-mapped.
*/
err = ubifs_leb_unmap(c, c->gc_lnum);
if (err)
return err;
}
err = dbg_check_lprops(c);
if (err)
goto out_orphans;
} else if (c->need_recovery) {
err = ubifs_recover_size(c);
if (err)
goto out_orphans;
} else {
/*
* Even if we mount read-only, we have to set space in GC LEB
* to proper value because this affects UBIFS free space
* reporting. We do not want to have a situation when
* re-mounting from R/O to R/W changes amount of free space.
*/
err = take_gc_lnum(c);
if (err)
goto out_orphans;
}
spin_lock(&ubifs_infos_lock);
list_add_tail(&c->infos_list, &ubifs_infos);
spin_unlock(&ubifs_infos_lock);
if (c->need_recovery) {
if (mounted_read_only)
ubifs_msg("recovery deferred");
else {
c->need_recovery = 0;
ubifs_msg("recovery completed");
/*
* GC LEB has to be empty and taken at this point. But
* the journal head LEBs may also be accounted as
* "empty taken" if they are empty.
*/
ubifs_assert(c->lst.taken_empty_lebs > 0);
}
} else
ubifs_assert(c->lst.taken_empty_lebs > 0);
err = dbg_check_filesystem(c);
if (err)
goto out_infos;
err = dbg_debugfs_init_fs(c);
if (err)
goto out_infos;
c->always_chk_crc = 0;
ubifs_msg("mounted UBI device %d, volume %d, name \"%s\"",
c->vi.ubi_num, c->vi.vol_id, c->vi.name);
if (mounted_read_only)
ubifs_msg("mounted read-only");
x = (long long)c->main_lebs * c->leb_size;
ubifs_msg("file system size: %lld bytes (%lld KiB, %lld MiB, %d "
"LEBs)", x, x >> 10, x >> 20, c->main_lebs);
x = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes;
ubifs_msg("journal size: %lld bytes (%lld KiB, %lld MiB, %d "
"LEBs)", x, x >> 10, x >> 20, c->log_lebs + c->max_bud_cnt);
ubifs_msg("media format: w%d/r%d (latest is w%d/r%d)",
c->fmt_version, c->ro_compat_version,
UBIFS_FORMAT_VERSION, UBIFS_RO_COMPAT_VERSION);
ubifs_msg("default compressor: %s", ubifs_compr_name(c->default_compr));
ubifs_msg("reserved for root: %llu bytes (%llu KiB)",
c->report_rp_size, c->report_rp_size >> 10);
dbg_msg("compiled on: " __DATE__ " at " __TIME__);
dbg_msg("min. I/O unit size: %d bytes", c->min_io_size);
dbg_msg("LEB size: %d bytes (%d KiB)",
c->leb_size, c->leb_size >> 10);
dbg_msg("data journal heads: %d",
c->jhead_cnt - NONDATA_JHEADS_CNT);
dbg_msg("UUID: %pUB", c->uuid);
dbg_msg("big_lpt %d", c->big_lpt);
dbg_msg("log LEBs: %d (%d - %d)",
c->log_lebs, UBIFS_LOG_LNUM, c->log_last);
dbg_msg("LPT area LEBs: %d (%d - %d)",
c->lpt_lebs, c->lpt_first, c->lpt_last);
dbg_msg("orphan area LEBs: %d (%d - %d)",
c->orph_lebs, c->orph_first, c->orph_last);
dbg_msg("main area LEBs: %d (%d - %d)",
c->main_lebs, c->main_first, c->leb_cnt - 1);
dbg_msg("index LEBs: %d", c->lst.idx_lebs);
dbg_msg("total index bytes: %lld (%lld KiB, %lld MiB)",
c->old_idx_sz, c->old_idx_sz >> 10, c->old_idx_sz >> 20);
dbg_msg("key hash type: %d", c->key_hash_type);
dbg_msg("tree fanout: %d", c->fanout);
dbg_msg("reserved GC LEB: %d", c->gc_lnum);
dbg_msg("first main LEB: %d", c->main_first);
dbg_msg("max. znode size %d", c->max_znode_sz);
dbg_msg("max. index node size %d", c->max_idx_node_sz);
dbg_msg("node sizes: data %zu, inode %zu, dentry %zu",
UBIFS_DATA_NODE_SZ, UBIFS_INO_NODE_SZ, UBIFS_DENT_NODE_SZ);
dbg_msg("node sizes: trun %zu, sb %zu, master %zu",
UBIFS_TRUN_NODE_SZ, UBIFS_SB_NODE_SZ, UBIFS_MST_NODE_SZ);
dbg_msg("node sizes: ref %zu, cmt. start %zu, orph %zu",
UBIFS_REF_NODE_SZ, UBIFS_CS_NODE_SZ, UBIFS_ORPH_NODE_SZ);
dbg_msg("max. node sizes: data %zu, inode %zu dentry %zu",
UBIFS_MAX_DATA_NODE_SZ, UBIFS_MAX_INO_NODE_SZ,
UBIFS_MAX_DENT_NODE_SZ);
dbg_msg("dead watermark: %d", c->dead_wm);
dbg_msg("dark watermark: %d", c->dark_wm);
dbg_msg("LEB overhead: %d", c->leb_overhead);
x = (long long)c->main_lebs * c->dark_wm;
dbg_msg("max. dark space: %lld (%lld KiB, %lld MiB)",
x, x >> 10, x >> 20);
dbg_msg("maximum bud bytes: %lld (%lld KiB, %lld MiB)",
c->max_bud_bytes, c->max_bud_bytes >> 10,
c->max_bud_bytes >> 20);
dbg_msg("BG commit bud bytes: %lld (%lld KiB, %lld MiB)",
c->bg_bud_bytes, c->bg_bud_bytes >> 10,
c->bg_bud_bytes >> 20);
dbg_msg("current bud bytes %lld (%lld KiB, %lld MiB)",
c->bud_bytes, c->bud_bytes >> 10, c->bud_bytes >> 20);
dbg_msg("max. seq. number: %llu", c->max_sqnum);
dbg_msg("commit number: %llu", c->cmt_no);
return 0;
out_infos:
spin_lock(&ubifs_infos_lock);
list_del(&c->infos_list);
spin_unlock(&ubifs_infos_lock);
out_orphans:
free_orphans(c);
out_journal:
destroy_journal(c);
out_lpt:
ubifs_lpt_free(c, 0);
out_master:
kfree(c->mst_node);
kfree(c->rcvrd_mst_node);
if (c->bgt)
kthread_stop(c->bgt);
out_wbufs:
free_wbufs(c);
out_cbuf:
kfree(c->cbuf);
out_free:
kfree(c->bu.buf);
vfree(c->ileb_buf);
vfree(c->sbuf);
kfree(c->bottom_up_buf);
ubifs_debugging_exit(c);
return err;
}
/**
* ubifs_umount - un-mount UBIFS file-system.
* @c: UBIFS file-system description object
*
* Note, this function is called to free allocated resourced when un-mounting,
* as well as free resources when an error occurred while we were half way
* through mounting (error path cleanup function). So it has to make sure the
* resource was actually allocated before freeing it.
*/
static void ubifs_umount(struct ubifs_info *c)
{
dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num,
c->vi.vol_id);
dbg_debugfs_exit_fs(c);
spin_lock(&ubifs_infos_lock);
list_del(&c->infos_list);
spin_unlock(&ubifs_infos_lock);
if (c->bgt)
kthread_stop(c->bgt);
destroy_journal(c);
free_wbufs(c);
free_orphans(c);
ubifs_lpt_free(c, 0);
kfree(c->cbuf);
kfree(c->rcvrd_mst_node);
kfree(c->mst_node);
kfree(c->bu.buf);
vfree(c->ileb_buf);
vfree(c->sbuf);
kfree(c->bottom_up_buf);
ubifs_debugging_exit(c);
}
/**
* ubifs_remount_rw - re-mount in read-write mode.
* @c: UBIFS file-system description object
*
* UBIFS avoids allocating many unnecessary resources when mounted in read-only
* mode. This function allocates the needed resources and re-mounts UBIFS in
* read-write mode.
*/
static int ubifs_remount_rw(struct ubifs_info *c)
{
int err, lnum;
if (c->rw_incompat) {
ubifs_err("the file-system is not R/W-compatible");
ubifs_msg("on-flash format version is w%d/r%d, but software "
"only supports up to version w%d/r%d", c->fmt_version,
c->ro_compat_version, UBIFS_FORMAT_VERSION,
UBIFS_RO_COMPAT_VERSION);
return -EROFS;
}
mutex_lock(&c->umount_mutex);
dbg_save_space_info(c);
c->remounting_rw = 1;
c->always_chk_crc = 1;
err = check_free_space(c);
if (err)
goto out;
if (c->old_leb_cnt != c->leb_cnt) {
struct ubifs_sb_node *sup;
sup = ubifs_read_sb_node(c);
if (IS_ERR(sup)) {
err = PTR_ERR(sup);
goto out;
}
sup->leb_cnt = cpu_to_le32(c->leb_cnt);
err = ubifs_write_sb_node(c, sup);
if (err)
goto out;
}
if (c->need_recovery) {
ubifs_msg("completing deferred recovery");
err = ubifs_write_rcvrd_mst_node(c);
if (err)
goto out;
err = ubifs_recover_size(c);
if (err)
goto out;
err = ubifs_clean_lebs(c, c->sbuf);
if (err)
goto out;
err = ubifs_recover_inl_heads(c, c->sbuf);
if (err)
goto out;
} else {
/* A readonly mount is not allowed to have orphans */
ubifs_assert(c->tot_orphans == 0);
err = ubifs_clear_orphans(c);
if (err)
goto out;
}
if (!(c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY))) {
c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
err = ubifs_write_master(c);
if (err)
goto out;
}
c->ileb_buf = vmalloc(c->leb_size);
if (!c->ileb_buf) {
err = -ENOMEM;
goto out;
}
err = ubifs_lpt_init(c, 0, 1);
if (err)
goto out;
err = alloc_wbufs(c);
if (err)
goto out;
ubifs_create_buds_lists(c);
/* Create background thread */
c->bgt = kthread_create(ubifs_bg_thread, c, "%s", c->bgt_name);
if (IS_ERR(c->bgt)) {
err = PTR_ERR(c->bgt);
c->bgt = NULL;
ubifs_err("cannot spawn \"%s\", error %d",
c->bgt_name, err);
goto out;
}
wake_up_process(c->bgt);
c->orph_buf = vmalloc(c->leb_size);
if (!c->orph_buf) {
err = -ENOMEM;
goto out;
}
/* Check for enough log space */
lnum = c->lhead_lnum + 1;
if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
lnum = UBIFS_LOG_LNUM;
if (lnum == c->ltail_lnum) {
err = ubifs_consolidate_log(c);
if (err)
goto out;
}
if (c->need_recovery)
err = ubifs_rcvry_gc_commit(c);
else
err = ubifs_leb_unmap(c, c->gc_lnum);
if (err)
goto out;
if (c->need_recovery) {
c->need_recovery = 0;
ubifs_msg("deferred recovery completed");
}
dbg_gen("re-mounted read-write");
c->vfs_sb->s_flags &= ~MS_RDONLY;
c->remounting_rw = 0;
c->always_chk_crc = 0;
err = dbg_check_space_info(c);
mutex_unlock(&c->umount_mutex);
return err;
out:
vfree(c->orph_buf);
c->orph_buf = NULL;
if (c->bgt) {
kthread_stop(c->bgt);
c->bgt = NULL;
}
free_wbufs(c);
vfree(c->ileb_buf);
c->ileb_buf = NULL;
ubifs_lpt_free(c, 1);
c->remounting_rw = 0;
c->always_chk_crc = 0;
mutex_unlock(&c->umount_mutex);
return err;
}
/**
* ubifs_remount_ro - re-mount in read-only mode.
* @c: UBIFS file-system description object
*
* We assume VFS has stopped writing. Possibly the background thread could be
* running a commit, however kthread_stop will wait in that case.
*/
static void ubifs_remount_ro(struct ubifs_info *c)
{
int i, err;
ubifs_assert(!c->need_recovery);
ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY));
mutex_lock(&c->umount_mutex);
if (c->bgt) {
kthread_stop(c->bgt);
c->bgt = NULL;
}
dbg_save_space_info(c);
for (i = 0; i < c->jhead_cnt; i++) {
ubifs_wbuf_sync(&c->jheads[i].wbuf);
hrtimer_cancel(&c->jheads[i].wbuf.timer);
}
c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
err = ubifs_write_master(c);
if (err)
ubifs_ro_mode(c, err);
free_wbufs(c);
vfree(c->orph_buf);
c->orph_buf = NULL;
vfree(c->ileb_buf);
c->ileb_buf = NULL;
ubifs_lpt_free(c, 1);
err = dbg_check_space_info(c);
if (err)
ubifs_ro_mode(c, err);
mutex_unlock(&c->umount_mutex);
}
static void ubifs_put_super(struct super_block *sb)
{
int i;
struct ubifs_info *c = sb->s_fs_info;
ubifs_msg("un-mount UBI device %d, volume %d", c->vi.ubi_num,
c->vi.vol_id);
/*
* The following asserts are only valid if there has not been a failure
* of the media. For example, there will be dirty inodes if we failed
* to write them back because of I/O errors.
*/
ubifs_assert(atomic_long_read(&c->dirty_pg_cnt) == 0);
ubifs_assert(c->budg_idx_growth == 0);
ubifs_assert(c->budg_dd_growth == 0);
ubifs_assert(c->budg_data_growth == 0);
/*
* The 'c->umount_lock' prevents races between UBIFS memory shrinker
* and file system un-mount. Namely, it prevents the shrinker from
* picking this superblock for shrinking - it will be just skipped if
* the mutex is locked.
*/
mutex_lock(&c->umount_mutex);
if (!(c->vfs_sb->s_flags & MS_RDONLY)) {
/*
* First of all kill the background thread to make sure it does
* not interfere with un-mounting and freeing resources.
*/
if (c->bgt) {
kthread_stop(c->bgt);
c->bgt = NULL;
}
/* Synchronize write-buffers */
if (c->jheads)
for (i = 0; i < c->jhead_cnt; i++)
ubifs_wbuf_sync(&c->jheads[i].wbuf);
/*
* On fatal errors c->ro_media is set to 1, in which case we do
* not write the master node.
*/
if (!c->ro_media) {
/*
* We are being cleanly unmounted which means the
* orphans were killed - indicate this in the master
* node. Also save the reserved GC LEB number.
*/
int err;
c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
err = ubifs_write_master(c);
if (err)
/*
* Recovery will attempt to fix the master area
* next mount, so we just print a message and
* continue to unmount normally.
*/
ubifs_err("failed to write master node, "
"error %d", err);
}
}
ubifs_umount(c);
bdi_destroy(&c->bdi);
ubi_close_volume(c->ubi);
mutex_unlock(&c->umount_mutex);
kfree(c);
}
static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
{
int err;
struct ubifs_info *c = sb->s_fs_info;
dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, *flags);
err = ubifs_parse_options(c, data, 1);
if (err) {
ubifs_err("invalid or unknown remount parameter");
return err;
}
if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
if (c->ro_media) {
ubifs_msg("cannot re-mount due to prior errors");
return -EROFS;
}
err = ubifs_remount_rw(c);
if (err)
return err;
} else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY)) {
if (c->ro_media) {
ubifs_msg("cannot re-mount due to prior errors");
return -EROFS;
}
ubifs_remount_ro(c);
}
if (c->bulk_read == 1)
bu_init(c);
else {
dbg_gen("disable bulk-read");
kfree(c->bu.buf);
c->bu.buf = NULL;
}
ubifs_assert(c->lst.taken_empty_lebs > 0);
return 0;
}
const struct super_operations ubifs_super_operations = {
.alloc_inode = ubifs_alloc_inode,
.destroy_inode = ubifs_destroy_inode,
.put_super = ubifs_put_super,
.write_inode = ubifs_write_inode,
.delete_inode = ubifs_delete_inode,
.statfs = ubifs_statfs,
.dirty_inode = ubifs_dirty_inode,
.remount_fs = ubifs_remount_fs,
.show_options = ubifs_show_options,
.sync_fs = ubifs_sync_fs,
};
/**
* open_ubi - parse UBI device name string and open the UBI device.
* @name: UBI volume name
* @mode: UBI volume open mode
*
* The primary method of mounting UBIFS is by specifying the UBI volume
* character device node path. However, UBIFS may also be mounted withoug any
* character device node using one of the following methods:
*
* o ubiX_Y - mount UBI device number X, volume Y;
* o ubiY - mount UBI device number 0, volume Y;
* o ubiX:NAME - mount UBI device X, volume with name NAME;
* o ubi:NAME - mount UBI device 0, volume with name NAME.
*
* Alternative '!' separator may be used instead of ':' (because some shells
* like busybox may interpret ':' as an NFS host name separator). This function
* returns UBI volume description object in case of success and a negative
* error code in case of failure.
*/
static struct ubi_volume_desc *open_ubi(const char *name, int mode)
{
struct ubi_volume_desc *ubi;
int dev, vol;
char *endptr;
/* First, try to open using the device node path method */
ubi = ubi_open_volume_path(name, mode);
if (!IS_ERR(ubi))
return ubi;
/* Try the "nodev" method */
if (name[0] != 'u' || name[1] != 'b' || name[2] != 'i')
return ERR_PTR(-EINVAL);
/* ubi:NAME method */
if ((name[3] == ':' || name[3] == '!') && name[4] != '\0')
return ubi_open_volume_nm(0, name + 4, mode);
if (!isdigit(name[3]))
return ERR_PTR(-EINVAL);
dev = simple_strtoul(name + 3, &endptr, 0);
/* ubiY method */
if (*endptr == '\0')
return ubi_open_volume(0, dev, mode);
/* ubiX_Y method */
if (*endptr == '_' && isdigit(endptr[1])) {
vol = simple_strtoul(endptr + 1, &endptr, 0);
if (*endptr != '\0')
return ERR_PTR(-EINVAL);
return ubi_open_volume(dev, vol, mode);
}
/* ubiX:NAME method */
if ((*endptr == ':' || *endptr == '!') && endptr[1] != '\0')
return ubi_open_volume_nm(dev, ++endptr, mode);
return ERR_PTR(-EINVAL);
}
static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
{
struct ubi_volume_desc *ubi = sb->s_fs_info;
struct ubifs_info *c;
struct inode *root;
int err;
c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL);
if (!c)
return -ENOMEM;
spin_lock_init(&c->cnt_lock);
spin_lock_init(&c->cs_lock);
spin_lock_init(&c->buds_lock);
spin_lock_init(&c->space_lock);
spin_lock_init(&c->orphan_lock);
init_rwsem(&c->commit_sem);
mutex_init(&c->lp_mutex);
mutex_init(&c->tnc_mutex);
mutex_init(&c->log_mutex);
mutex_init(&c->mst_mutex);
mutex_init(&c->umount_mutex);
mutex_init(&c->bu_mutex);
init_waitqueue_head(&c->cmt_wq);
c->buds = RB_ROOT;
c->old_idx = RB_ROOT;
c->size_tree = RB_ROOT;
c->orph_tree = RB_ROOT;
INIT_LIST_HEAD(&c->infos_list);
INIT_LIST_HEAD(&c->idx_gc);
INIT_LIST_HEAD(&c->replay_list);
INIT_LIST_HEAD(&c->replay_buds);
INIT_LIST_HEAD(&c->uncat_list);
INIT_LIST_HEAD(&c->empty_list);
INIT_LIST_HEAD(&c->freeable_list);
INIT_LIST_HEAD(&c->frdi_idx_list);
INIT_LIST_HEAD(&c->unclean_leb_list);
INIT_LIST_HEAD(&c->old_buds);
INIT_LIST_HEAD(&c->orph_list);
INIT_LIST_HEAD(&c->orph_new);
c->vfs_sb = sb;
c->highest_inum = UBIFS_FIRST_INO;
c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM;
ubi_get_volume_info(ubi, &c->vi);
ubi_get_device_info(c->vi.ubi_num, &c->di);
/* Re-open the UBI device in read-write mode */
c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READWRITE);
if (IS_ERR(c->ubi)) {
err = PTR_ERR(c->ubi);
goto out_free;
}
/*
* UBIFS provides 'backing_dev_info' in order to disable read-ahead. For
* UBIFS, I/O is not deferred, it is done immediately in readpage,
* which means the user would have to wait not just for their own I/O
* but the read-ahead I/O as well i.e. completely pointless.
*
* Read-ahead will be disabled because @c->bdi.ra_pages is 0.
*/
c->bdi.name = "ubifs",
c->bdi.capabilities = BDI_CAP_MAP_COPY;
c->bdi.unplug_io_fn = default_unplug_io_fn;
err = bdi_init(&c->bdi);
if (err)
goto out_close;
err = bdi_register(&c->bdi, NULL, "ubifs_%d_%d",
c->vi.ubi_num, c->vi.vol_id);
if (err)
goto out_bdi;
err = ubifs_parse_options(c, data, 0);
if (err)
goto out_bdi;
sb->s_bdi = &c->bdi;
sb->s_fs_info = c;
sb->s_magic = UBIFS_SUPER_MAGIC;
sb->s_blocksize = UBIFS_BLOCK_SIZE;
sb->s_blocksize_bits = UBIFS_BLOCK_SHIFT;
sb->s_maxbytes = c->max_inode_sz = key_max_inode_size(c);
if (c->max_inode_sz > MAX_LFS_FILESIZE)
sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE;
sb->s_op = &ubifs_super_operations;
mutex_lock(&c->umount_mutex);
err = mount_ubifs(c);
if (err) {
ubifs_assert(err < 0);
goto out_unlock;
}
/* Read the root inode */
root = ubifs_iget(sb, UBIFS_ROOT_INO);
if (IS_ERR(root)) {
err = PTR_ERR(root);
goto out_umount;
}
sb->s_root = d_alloc_root(root);
if (!sb->s_root)
goto out_iput;
mutex_unlock(&c->umount_mutex);
return 0;
out_iput:
iput(root);
out_umount:
ubifs_umount(c);
out_unlock:
mutex_unlock(&c->umount_mutex);
out_bdi:
bdi_destroy(&c->bdi);
out_close:
ubi_close_volume(c->ubi);
out_free:
kfree(c);
return err;
}
static int sb_test(struct super_block *sb, void *data)
{
dev_t *dev = data;
struct ubifs_info *c = sb->s_fs_info;
return c->vi.cdev == *dev;
}
static int ubifs_get_sb(struct file_system_type *fs_type, int flags,
const char *name, void *data, struct vfsmount *mnt)
{
struct ubi_volume_desc *ubi;
struct ubi_volume_info vi;
struct super_block *sb;
int err;
dbg_gen("name %s, flags %#x", name, flags);
/*
* Get UBI device number and volume ID. Mount it read-only so far
* because this might be a new mount point, and UBI allows only one
* read-write user at a time.
*/
ubi = open_ubi(name, UBI_READONLY);
if (IS_ERR(ubi)) {
ubifs_err("cannot open \"%s\", error %d",
name, (int)PTR_ERR(ubi));
return PTR_ERR(ubi);
}
ubi_get_volume_info(ubi, &vi);
dbg_gen("opened ubi%d_%d", vi.ubi_num, vi.vol_id);
sb = sget(fs_type, &sb_test, &set_anon_super, &vi.cdev);
if (IS_ERR(sb)) {
err = PTR_ERR(sb);
goto out_close;
}
if (sb->s_root) {
/* A new mount point for already mounted UBIFS */
dbg_gen("this ubi volume is already mounted");
if ((flags ^ sb->s_flags) & MS_RDONLY) {
err = -EBUSY;
goto out_deact;
}
} else {
sb->s_flags = flags;
/*
* Pass 'ubi' to 'fill_super()' in sb->s_fs_info where it is
* replaced by 'c'.
*/
sb->s_fs_info = ubi;
err = ubifs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
if (err)
goto out_deact;
/* We do not support atime */
sb->s_flags |= MS_ACTIVE | MS_NOATIME;
}
/* 'fill_super()' opens ubi again so we must close it here */
ubi_close_volume(ubi);
simple_set_mnt(mnt, sb);
return 0;
out_deact:
deactivate_locked_super(sb);
out_close:
ubi_close_volume(ubi);
return err;
}
static struct file_system_type ubifs_fs_type = {
.name = "ubifs",
.owner = THIS_MODULE,
.get_sb = ubifs_get_sb,
.kill_sb = kill_anon_super,
};
/*
* Inode slab cache constructor.
*/
static void inode_slab_ctor(void *obj)
{
struct ubifs_inode *ui = obj;
inode_init_once(&ui->vfs_inode);
}
static int __init ubifs_init(void)
{
int err;
BUILD_BUG_ON(sizeof(struct ubifs_ch) != 24);
/* Make sure node sizes are 8-byte aligned */
BUILD_BUG_ON(UBIFS_CH_SZ & 7);
BUILD_BUG_ON(UBIFS_INO_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_DENT_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_XENT_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_DATA_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_SB_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_MST_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_REF_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_CS_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_ORPH_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ & 7);
BUILD_BUG_ON(UBIFS_MAX_NODE_SZ & 7);
BUILD_BUG_ON(MIN_WRITE_SZ & 7);
/* Check min. node size */
BUILD_BUG_ON(UBIFS_INO_NODE_SZ < MIN_WRITE_SZ);
BUILD_BUG_ON(UBIFS_DENT_NODE_SZ < MIN_WRITE_SZ);
BUILD_BUG_ON(UBIFS_XENT_NODE_SZ < MIN_WRITE_SZ);
BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ < MIN_WRITE_SZ);
BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ > UBIFS_MAX_NODE_SZ);
BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ > UBIFS_MAX_NODE_SZ);
/* Defined node sizes */
BUILD_BUG_ON(UBIFS_SB_NODE_SZ != 4096);
BUILD_BUG_ON(UBIFS_MST_NODE_SZ != 512);
BUILD_BUG_ON(UBIFS_INO_NODE_SZ != 160);
BUILD_BUG_ON(UBIFS_REF_NODE_SZ != 64);
/*
* We use 2 bit wide bit-fields to store compression type, which should
* be amended if more compressors are added. The bit-fields are:
* @compr_type in 'struct ubifs_inode', @default_compr in
* 'struct ubifs_info' and @compr_type in 'struct ubifs_mount_opts'.
*/
BUILD_BUG_ON(UBIFS_COMPR_TYPES_CNT > 4);
/*
* We require that PAGE_CACHE_SIZE is greater-than-or-equal-to
* UBIFS_BLOCK_SIZE. It is assumed that both are powers of 2.
*/
if (PAGE_CACHE_SIZE < UBIFS_BLOCK_SIZE) {
ubifs_err("VFS page cache size is %u bytes, but UBIFS requires"
" at least 4096 bytes",
(unsigned int)PAGE_CACHE_SIZE);
return -EINVAL;
}
err = register_filesystem(&ubifs_fs_type);
if (err) {
ubifs_err("cannot register file system, error %d", err);
return err;
}
err = -ENOMEM;
ubifs_inode_slab = kmem_cache_create("ubifs_inode_slab",
sizeof(struct ubifs_inode), 0,
SLAB_MEM_SPREAD | SLAB_RECLAIM_ACCOUNT,
&inode_slab_ctor);
if (!ubifs_inode_slab)
goto out_reg;
register_shrinker(&ubifs_shrinker_info);
err = ubifs_compressors_init();
if (err)
goto out_shrinker;
err = dbg_debugfs_init();
if (err)
goto out_compr;
return 0;
out_compr:
ubifs_compressors_exit();
out_shrinker:
unregister_shrinker(&ubifs_shrinker_info);
kmem_cache_destroy(ubifs_inode_slab);
out_reg:
unregister_filesystem(&ubifs_fs_type);
return err;
}
/* late_initcall to let compressors initialize first */
late_initcall(ubifs_init);
static void __exit ubifs_exit(void)
{
ubifs_assert(list_empty(&ubifs_infos));
ubifs_assert(atomic_long_read(&ubifs_clean_zn_cnt) == 0);
dbg_debugfs_exit();
ubifs_compressors_exit();
unregister_shrinker(&ubifs_shrinker_info);
kmem_cache_destroy(ubifs_inode_slab);
unregister_filesystem(&ubifs_fs_type);
}
module_exit(ubifs_exit);
MODULE_LICENSE("GPL");
MODULE_VERSION(__stringify(UBIFS_VERSION));
MODULE_AUTHOR("Artem Bityutskiy, Adrian Hunter");
MODULE_DESCRIPTION("UBIFS - UBI File System");
Reference in New Issue View Git Blame Copy Permalink