/*
|
* This file is part of UBIFS.
|
*
|
* Copyright (C) 2006-2008 Nokia Corporation.
|
* Copyright (C) 2006, 2007 University of Szeged, Hungary
|
*
|
* SPDX-License-Identifier: GPL-2.0+
|
*
|
* Authors: Artem Bityutskiy (Битюцкий Артём)
|
* Adrian Hunter
|
* Zoltan Sogor
|
*/
|
|
/*
|
* This file implements UBIFS I/O subsystem which provides various I/O-related
|
* helper functions (reading/writing/checking/validating nodes) and implements
|
* write-buffering support. Write buffers help to save space which otherwise
|
* would have been wasted for padding to the nearest minimal I/O unit boundary.
|
* Instead, data first goes to the write-buffer and is flushed when the
|
* buffer is full or when it is not used for some time (by timer). This is
|
* similar to the mechanism is used by JFFS2.
|
*
|
* UBIFS distinguishes between minimum write size (@c->min_io_size) and maximum
|
* write size (@c->max_write_size). The latter is the maximum amount of bytes
|
* the underlying flash is able to program at a time, and writing in
|
* @c->max_write_size units should presumably be faster. Obviously,
|
* @c->min_io_size <= @c->max_write_size. Write-buffers are of
|
* @c->max_write_size bytes in size for maximum performance. However, when a
|
* write-buffer is flushed, only the portion of it (aligned to @c->min_io_size
|
* boundary) which contains data is written, not the whole write-buffer,
|
* because this is more space-efficient.
|
*
|
* This optimization adds few complications to the code. Indeed, on the one
|
* hand, we want to write in optimal @c->max_write_size bytes chunks, which
|
* also means aligning writes at the @c->max_write_size bytes offsets. On the
|
* other hand, we do not want to waste space when synchronizing the write
|
* buffer, so during synchronization we writes in smaller chunks. And this makes
|
* the next write offset to be not aligned to @c->max_write_size bytes. So the
|
* have to make sure that the write-buffer offset (@wbuf->offs) becomes aligned
|
* to @c->max_write_size bytes again. We do this by temporarily shrinking
|
* write-buffer size (@wbuf->size).
|
*
|
* Write-buffers are defined by 'struct ubifs_wbuf' objects and protected by
|
* mutexes defined inside these objects. Since sometimes upper-level code
|
* has to lock the write-buffer (e.g. journal space reservation code), many
|
* functions related to write-buffers have "nolock" suffix which means that the
|
* caller has to lock the write-buffer before calling this function.
|
*
|
* UBIFS stores nodes at 64 bit-aligned addresses. If the node length is not
|
* aligned, UBIFS starts the next node from the aligned address, and the padded
|
* bytes may contain any rubbish. In other words, UBIFS does not put padding
|
* bytes in those small gaps. Common headers of nodes store real node lengths,
|
* not aligned lengths. Indexing nodes also store real lengths in branches.
|
*
|
* UBIFS uses padding when it pads to the next min. I/O unit. In this case it
|
* uses padding nodes or padding bytes, if the padding node does not fit.
|
*
|
* All UBIFS nodes are protected by CRC checksums and UBIFS checks CRC when
|
* they are read from the flash media.
|
*/
|
|
#ifndef __UBOOT__
|
#include <linux/crc32.h>
|
#include <linux/slab.h>
|
#else
|
#include <linux/compat.h>
|
#include <linux/err.h>
|
#endif
|
#include "ubifs.h"
|
|
/**
|
* ubifs_ro_mode - switch UBIFS to read read-only mode.
|
* @c: UBIFS file-system description object
|
* @err: error code which is the reason of switching to R/O mode
|
*/
|
void ubifs_ro_mode(struct ubifs_info *c, int err)
|
{
|
if (!c->ro_error) {
|
c->ro_error = 1;
|
c->no_chk_data_crc = 0;
|
c->vfs_sb->s_flags |= MS_RDONLY;
|
ubifs_warn(c, "switched to read-only mode, error %d", err);
|
dump_stack();
|
}
|
}
|
|
/*
|
* Below are simple wrappers over UBI I/O functions which include some
|
* additional checks and UBIFS debugging stuff. See corresponding UBI function
|
* for more information.
|
*/
|
|
int ubifs_leb_read(const struct ubifs_info *c, int lnum, void *buf, int offs,
|
int len, int even_ebadmsg)
|
{
|
int err;
|
|
err = ubi_read(c->ubi, lnum, buf, offs, len);
|
/*
|
* In case of %-EBADMSG print the error message only if the
|
* @even_ebadmsg is true.
|
*/
|
if (err && (err != -EBADMSG || even_ebadmsg)) {
|
ubifs_err(c, "reading %d bytes from LEB %d:%d failed, error %d",
|
len, lnum, offs, err);
|
dump_stack();
|
}
|
return err;
|
}
|
|
int ubifs_leb_write(struct ubifs_info *c, int lnum, const void *buf, int offs,
|
int len)
|
{
|
int err;
|
|
ubifs_assert(!c->ro_media && !c->ro_mount);
|
if (c->ro_error)
|
return -EROFS;
|
if (!dbg_is_tst_rcvry(c))
|
err = ubi_leb_write(c->ubi, lnum, buf, offs, len);
|
#ifndef __UBOOT__
|
else
|
err = dbg_leb_write(c, lnum, buf, offs, len);
|
#endif
|
if (err) {
|
ubifs_err(c, "writing %d bytes to LEB %d:%d failed, error %d",
|
len, lnum, offs, err);
|
ubifs_ro_mode(c, err);
|
dump_stack();
|
}
|
return err;
|
}
|
|
int ubifs_leb_change(struct ubifs_info *c, int lnum, const void *buf, int len)
|
{
|
int err;
|
|
ubifs_assert(!c->ro_media && !c->ro_mount);
|
if (c->ro_error)
|
return -EROFS;
|
if (!dbg_is_tst_rcvry(c))
|
err = ubi_leb_change(c->ubi, lnum, buf, len);
|
#ifndef __UBOOT__
|
else
|
err = dbg_leb_change(c, lnum, buf, len);
|
#endif
|
if (err) {
|
ubifs_err(c, "changing %d bytes in LEB %d failed, error %d",
|
len, lnum, err);
|
ubifs_ro_mode(c, err);
|
dump_stack();
|
}
|
return err;
|
}
|
|
int ubifs_leb_unmap(struct ubifs_info *c, int lnum)
|
{
|
int err;
|
|
ubifs_assert(!c->ro_media && !c->ro_mount);
|
if (c->ro_error)
|
return -EROFS;
|
if (!dbg_is_tst_rcvry(c))
|
err = ubi_leb_unmap(c->ubi, lnum);
|
#ifndef __UBOOT__
|
else
|
err = dbg_leb_unmap(c, lnum);
|
#endif
|
if (err) {
|
ubifs_err(c, "unmap LEB %d failed, error %d", lnum, err);
|
ubifs_ro_mode(c, err);
|
dump_stack();
|
}
|
return err;
|
}
|
|
int ubifs_leb_map(struct ubifs_info *c, int lnum)
|
{
|
int err;
|
|
ubifs_assert(!c->ro_media && !c->ro_mount);
|
if (c->ro_error)
|
return -EROFS;
|
if (!dbg_is_tst_rcvry(c))
|
err = ubi_leb_map(c->ubi, lnum);
|
#ifndef __UBOOT__
|
else
|
err = dbg_leb_map(c, lnum);
|
#endif
|
if (err) {
|
ubifs_err(c, "mapping LEB %d failed, error %d", lnum, err);
|
ubifs_ro_mode(c, err);
|
dump_stack();
|
}
|
return err;
|
}
|
|
int ubifs_is_mapped(const struct ubifs_info *c, int lnum)
|
{
|
int err;
|
|
err = ubi_is_mapped(c->ubi, lnum);
|
if (err < 0) {
|
ubifs_err(c, "ubi_is_mapped failed for LEB %d, error %d",
|
lnum, err);
|
dump_stack();
|
}
|
return err;
|
}
|
|
/**
|
* ubifs_check_node - check node.
|
* @c: UBIFS file-system description object
|
* @buf: node to check
|
* @lnum: logical eraseblock number
|
* @offs: offset within the logical eraseblock
|
* @quiet: print no messages
|
* @must_chk_crc: indicates whether to always check the CRC
|
*
|
* This function checks node magic number and CRC checksum. This function also
|
* validates node length to prevent UBIFS from becoming crazy when an attacker
|
* feeds it a file-system image with incorrect nodes. For example, too large
|
* node length in the common header could cause UBIFS to read memory outside of
|
* allocated buffer when checking the CRC checksum.
|
*
|
* This function may skip data nodes CRC checking if @c->no_chk_data_crc is
|
* true, which is controlled by corresponding UBIFS mount option. However, if
|
* @must_chk_crc is true, then @c->no_chk_data_crc is ignored and CRC is
|
* checked. Similarly, if @c->mounting or @c->remounting_rw is true (we are
|
* mounting or re-mounting to R/W mode), @c->no_chk_data_crc is ignored and CRC
|
* is checked. This is because during mounting or re-mounting from R/O mode to
|
* R/W mode we may read journal nodes (when replying the journal or doing the
|
* recovery) and the journal nodes may potentially be corrupted, so checking is
|
* required.
|
*
|
* This function returns zero in case of success and %-EUCLEAN in case of bad
|
* CRC or magic.
|
*/
|
int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
|
int offs, int quiet, int must_chk_crc)
|
{
|
int err = -EINVAL, type, node_len;
|
uint32_t crc, node_crc, magic;
|
const struct ubifs_ch *ch = buf;
|
|
ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
|
ubifs_assert(!(offs & 7) && offs < c->leb_size);
|
|
magic = le32_to_cpu(ch->magic);
|
if (magic != UBIFS_NODE_MAGIC) {
|
if (!quiet)
|
ubifs_err(c, "bad magic %#08x, expected %#08x",
|
magic, UBIFS_NODE_MAGIC);
|
err = -EUCLEAN;
|
goto out;
|
}
|
|
type = ch->node_type;
|
if (type < 0 || type >= UBIFS_NODE_TYPES_CNT) {
|
if (!quiet)
|
ubifs_err(c, "bad node type %d", type);
|
goto out;
|
}
|
|
node_len = le32_to_cpu(ch->len);
|
if (node_len + offs > c->leb_size)
|
goto out_len;
|
|
if (c->ranges[type].max_len == 0) {
|
if (node_len != c->ranges[type].len)
|
goto out_len;
|
} else if (node_len < c->ranges[type].min_len ||
|
node_len > c->ranges[type].max_len)
|
goto out_len;
|
|
if (!must_chk_crc && type == UBIFS_DATA_NODE && !c->mounting &&
|
!c->remounting_rw && c->no_chk_data_crc)
|
return 0;
|
|
crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
|
node_crc = le32_to_cpu(ch->crc);
|
if (crc != node_crc) {
|
if (!quiet)
|
ubifs_err(c, "bad CRC: calculated %#08x, read %#08x",
|
crc, node_crc);
|
err = -EUCLEAN;
|
goto out;
|
}
|
|
return 0;
|
|
out_len:
|
if (!quiet)
|
ubifs_err(c, "bad node length %d", node_len);
|
out:
|
if (!quiet) {
|
ubifs_err(c, "bad node at LEB %d:%d", lnum, offs);
|
ubifs_dump_node(c, buf);
|
dump_stack();
|
}
|
return err;
|
}
|
|
/**
|
* ubifs_pad - pad flash space.
|
* @c: UBIFS file-system description object
|
* @buf: buffer to put padding to
|
* @pad: how many bytes to pad
|
*
|
* The flash media obliges us to write only in chunks of %c->min_io_size and
|
* when we have to write less data we add padding node to the write-buffer and
|
* pad it to the next minimal I/O unit's boundary. Padding nodes help when the
|
* media is being scanned. If the amount of wasted space is not enough to fit a
|
* padding node which takes %UBIFS_PAD_NODE_SZ bytes, we write padding bytes
|
* pattern (%UBIFS_PADDING_BYTE).
|
*
|
* Padding nodes are also used to fill gaps when the "commit-in-gaps" method is
|
* used.
|
*/
|
void ubifs_pad(const struct ubifs_info *c, void *buf, int pad)
|
{
|
uint32_t crc;
|
|
ubifs_assert(pad >= 0 && !(pad & 7));
|
|
if (pad >= UBIFS_PAD_NODE_SZ) {
|
struct ubifs_ch *ch = buf;
|
struct ubifs_pad_node *pad_node = buf;
|
|
ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
|
ch->node_type = UBIFS_PAD_NODE;
|
ch->group_type = UBIFS_NO_NODE_GROUP;
|
ch->padding[0] = ch->padding[1] = 0;
|
ch->sqnum = 0;
|
ch->len = cpu_to_le32(UBIFS_PAD_NODE_SZ);
|
pad -= UBIFS_PAD_NODE_SZ;
|
pad_node->pad_len = cpu_to_le32(pad);
|
crc = crc32(UBIFS_CRC32_INIT, buf + 8, UBIFS_PAD_NODE_SZ - 8);
|
ch->crc = cpu_to_le32(crc);
|
memset(buf + UBIFS_PAD_NODE_SZ, 0, pad);
|
} else if (pad > 0)
|
/* Too little space, padding node won't fit */
|
memset(buf, UBIFS_PADDING_BYTE, pad);
|
}
|
|
/**
|
* next_sqnum - get next sequence number.
|
* @c: UBIFS file-system description object
|
*/
|
static unsigned long long next_sqnum(struct ubifs_info *c)
|
{
|
unsigned long long sqnum;
|
|
spin_lock(&c->cnt_lock);
|
sqnum = ++c->max_sqnum;
|
spin_unlock(&c->cnt_lock);
|
|
if (unlikely(sqnum >= SQNUM_WARN_WATERMARK)) {
|
if (sqnum >= SQNUM_WATERMARK) {
|
ubifs_err(c, "sequence number overflow %llu, end of life",
|
sqnum);
|
ubifs_ro_mode(c, -EINVAL);
|
}
|
ubifs_warn(c, "running out of sequence numbers, end of life soon");
|
}
|
|
return sqnum;
|
}
|
|
/**
|
* ubifs_prepare_node - prepare node to be written to flash.
|
* @c: UBIFS file-system description object
|
* @node: the node to pad
|
* @len: node length
|
* @pad: if the buffer has to be padded
|
*
|
* This function prepares node at @node to be written to the media - it
|
* calculates node CRC, fills the common header, and adds proper padding up to
|
* the next minimum I/O unit if @pad is not zero.
|
*/
|
void ubifs_prepare_node(struct ubifs_info *c, void *node, int len, int pad)
|
{
|
uint32_t crc;
|
struct ubifs_ch *ch = node;
|
unsigned long long sqnum = next_sqnum(c);
|
|
ubifs_assert(len >= UBIFS_CH_SZ);
|
|
ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
|
ch->len = cpu_to_le32(len);
|
ch->group_type = UBIFS_NO_NODE_GROUP;
|
ch->sqnum = cpu_to_le64(sqnum);
|
ch->padding[0] = ch->padding[1] = 0;
|
crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8);
|
ch->crc = cpu_to_le32(crc);
|
|
if (pad) {
|
len = ALIGN(len, 8);
|
pad = ALIGN(len, c->min_io_size) - len;
|
ubifs_pad(c, node + len, pad);
|
}
|
}
|
|
/**
|
* ubifs_prep_grp_node - prepare node of a group to be written to flash.
|
* @c: UBIFS file-system description object
|
* @node: the node to pad
|
* @len: node length
|
* @last: indicates the last node of the group
|
*
|
* This function prepares node at @node to be written to the media - it
|
* calculates node CRC and fills the common header.
|
*/
|
void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last)
|
{
|
uint32_t crc;
|
struct ubifs_ch *ch = node;
|
unsigned long long sqnum = next_sqnum(c);
|
|
ubifs_assert(len >= UBIFS_CH_SZ);
|
|
ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
|
ch->len = cpu_to_le32(len);
|
if (last)
|
ch->group_type = UBIFS_LAST_OF_NODE_GROUP;
|
else
|
ch->group_type = UBIFS_IN_NODE_GROUP;
|
ch->sqnum = cpu_to_le64(sqnum);
|
ch->padding[0] = ch->padding[1] = 0;
|
crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8);
|
ch->crc = cpu_to_le32(crc);
|
}
|
|
#ifndef __UBOOT__
|
/**
|
* wbuf_timer_callback - write-buffer timer callback function.
|
* @timer: timer data (write-buffer descriptor)
|
*
|
* This function is called when the write-buffer timer expires.
|
*/
|
static enum hrtimer_restart wbuf_timer_callback_nolock(struct hrtimer *timer)
|
{
|
struct ubifs_wbuf *wbuf = container_of(timer, struct ubifs_wbuf, timer);
|
|
dbg_io("jhead %s", dbg_jhead(wbuf->jhead));
|
wbuf->need_sync = 1;
|
wbuf->c->need_wbuf_sync = 1;
|
ubifs_wake_up_bgt(wbuf->c);
|
return HRTIMER_NORESTART;
|
}
|
|
/**
|
* new_wbuf_timer - start new write-buffer timer.
|
* @wbuf: write-buffer descriptor
|
*/
|
static void new_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
|
{
|
ubifs_assert(!hrtimer_active(&wbuf->timer));
|
|
if (wbuf->no_timer)
|
return;
|
dbg_io("set timer for jhead %s, %llu-%llu millisecs",
|
dbg_jhead(wbuf->jhead),
|
div_u64(ktime_to_ns(wbuf->softlimit), USEC_PER_SEC),
|
div_u64(ktime_to_ns(wbuf->softlimit) + wbuf->delta,
|
USEC_PER_SEC));
|
hrtimer_start_range_ns(&wbuf->timer, wbuf->softlimit, wbuf->delta,
|
HRTIMER_MODE_REL);
|
}
|
#endif
|
|
/**
|
* cancel_wbuf_timer - cancel write-buffer timer.
|
* @wbuf: write-buffer descriptor
|
*/
|
static void cancel_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
|
{
|
if (wbuf->no_timer)
|
return;
|
wbuf->need_sync = 0;
|
#ifndef __UBOOT__
|
hrtimer_cancel(&wbuf->timer);
|
#endif
|
}
|
|
/**
|
* ubifs_wbuf_sync_nolock - synchronize write-buffer.
|
* @wbuf: write-buffer to synchronize
|
*
|
* This function synchronizes write-buffer @buf and returns zero in case of
|
* success or a negative error code in case of failure.
|
*
|
* Note, although write-buffers are of @c->max_write_size, this function does
|
* not necessarily writes all @c->max_write_size bytes to the flash. Instead,
|
* if the write-buffer is only partially filled with data, only the used part
|
* of the write-buffer (aligned on @c->min_io_size boundary) is synchronized.
|
* This way we waste less space.
|
*/
|
int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf)
|
{
|
struct ubifs_info *c = wbuf->c;
|
int err, dirt, sync_len;
|
|
cancel_wbuf_timer_nolock(wbuf);
|
if (!wbuf->used || wbuf->lnum == -1)
|
/* Write-buffer is empty or not seeked */
|
return 0;
|
|
dbg_io("LEB %d:%d, %d bytes, jhead %s",
|
wbuf->lnum, wbuf->offs, wbuf->used, dbg_jhead(wbuf->jhead));
|
ubifs_assert(!(wbuf->avail & 7));
|
ubifs_assert(wbuf->offs + wbuf->size <= c->leb_size);
|
ubifs_assert(wbuf->size >= c->min_io_size);
|
ubifs_assert(wbuf->size <= c->max_write_size);
|
ubifs_assert(wbuf->size % c->min_io_size == 0);
|
ubifs_assert(!c->ro_media && !c->ro_mount);
|
if (c->leb_size - wbuf->offs >= c->max_write_size)
|
ubifs_assert(!((wbuf->offs + wbuf->size) % c->max_write_size));
|
|
if (c->ro_error)
|
return -EROFS;
|
|
/*
|
* Do not write whole write buffer but write only the minimum necessary
|
* amount of min. I/O units.
|
*/
|
sync_len = ALIGN(wbuf->used, c->min_io_size);
|
dirt = sync_len - wbuf->used;
|
if (dirt)
|
ubifs_pad(c, wbuf->buf + wbuf->used, dirt);
|
err = ubifs_leb_write(c, wbuf->lnum, wbuf->buf, wbuf->offs, sync_len);
|
if (err)
|
return err;
|
|
spin_lock(&wbuf->lock);
|
wbuf->offs += sync_len;
|
/*
|
* Now @wbuf->offs is not necessarily aligned to @c->max_write_size.
|
* But our goal is to optimize writes and make sure we write in
|
* @c->max_write_size chunks and to @c->max_write_size-aligned offset.
|
* Thus, if @wbuf->offs is not aligned to @c->max_write_size now, make
|
* sure that @wbuf->offs + @wbuf->size is aligned to
|
* @c->max_write_size. This way we make sure that after next
|
* write-buffer flush we are again at the optimal offset (aligned to
|
* @c->max_write_size).
|
*/
|
if (c->leb_size - wbuf->offs < c->max_write_size)
|
wbuf->size = c->leb_size - wbuf->offs;
|
else if (wbuf->offs & (c->max_write_size - 1))
|
wbuf->size = ALIGN(wbuf->offs, c->max_write_size) - wbuf->offs;
|
else
|
wbuf->size = c->max_write_size;
|
wbuf->avail = wbuf->size;
|
wbuf->used = 0;
|
wbuf->next_ino = 0;
|
spin_unlock(&wbuf->lock);
|
|
if (wbuf->sync_callback)
|
err = wbuf->sync_callback(c, wbuf->lnum,
|
c->leb_size - wbuf->offs, dirt);
|
return err;
|
}
|
|
/**
|
* ubifs_wbuf_seek_nolock - seek write-buffer.
|
* @wbuf: write-buffer
|
* @lnum: logical eraseblock number to seek to
|
* @offs: logical eraseblock offset to seek to
|
*
|
* This function targets the write-buffer to logical eraseblock @lnum:@offs.
|
* The write-buffer has to be empty. Returns zero in case of success and a
|
* negative error code in case of failure.
|
*/
|
int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs)
|
{
|
const struct ubifs_info *c = wbuf->c;
|
|
dbg_io("LEB %d:%d, jhead %s", lnum, offs, dbg_jhead(wbuf->jhead));
|
ubifs_assert(lnum >= 0 && lnum < c->leb_cnt);
|
ubifs_assert(offs >= 0 && offs <= c->leb_size);
|
ubifs_assert(offs % c->min_io_size == 0 && !(offs & 7));
|
ubifs_assert(lnum != wbuf->lnum);
|
ubifs_assert(wbuf->used == 0);
|
|
spin_lock(&wbuf->lock);
|
wbuf->lnum = lnum;
|
wbuf->offs = offs;
|
if (c->leb_size - wbuf->offs < c->max_write_size)
|
wbuf->size = c->leb_size - wbuf->offs;
|
else if (wbuf->offs & (c->max_write_size - 1))
|
wbuf->size = ALIGN(wbuf->offs, c->max_write_size) - wbuf->offs;
|
else
|
wbuf->size = c->max_write_size;
|
wbuf->avail = wbuf->size;
|
wbuf->used = 0;
|
spin_unlock(&wbuf->lock);
|
|
return 0;
|
}
|
|
#ifndef __UBOOT__
|
/**
|
* ubifs_bg_wbufs_sync - synchronize write-buffers.
|
* @c: UBIFS file-system description object
|
*
|
* This function is called by background thread to synchronize write-buffers.
|
* Returns zero in case of success and a negative error code in case of
|
* failure.
|
*/
|
int ubifs_bg_wbufs_sync(struct ubifs_info *c)
|
{
|
int err, i;
|
|
ubifs_assert(!c->ro_media && !c->ro_mount);
|
if (!c->need_wbuf_sync)
|
return 0;
|
c->need_wbuf_sync = 0;
|
|
if (c->ro_error) {
|
err = -EROFS;
|
goto out_timers;
|
}
|
|
dbg_io("synchronize");
|
for (i = 0; i < c->jhead_cnt; i++) {
|
struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
|
|
cond_resched();
|
|
/*
|
* If the mutex is locked then wbuf is being changed, so
|
* synchronization is not necessary.
|
*/
|
if (mutex_is_locked(&wbuf->io_mutex))
|
continue;
|
|
mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
|
if (!wbuf->need_sync) {
|
mutex_unlock(&wbuf->io_mutex);
|
continue;
|
}
|
|
err = ubifs_wbuf_sync_nolock(wbuf);
|
mutex_unlock(&wbuf->io_mutex);
|
if (err) {
|
ubifs_err(c, "cannot sync write-buffer, error %d", err);
|
ubifs_ro_mode(c, err);
|
goto out_timers;
|
}
|
}
|
|
return 0;
|
|
out_timers:
|
/* Cancel all timers to prevent repeated errors */
|
for (i = 0; i < c->jhead_cnt; i++) {
|
struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
|
|
mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
|
cancel_wbuf_timer_nolock(wbuf);
|
mutex_unlock(&wbuf->io_mutex);
|
}
|
return err;
|
}
|
|
/**
|
* ubifs_wbuf_write_nolock - write data to flash via write-buffer.
|
* @wbuf: write-buffer
|
* @buf: node to write
|
* @len: node length
|
*
|
* This function writes data to flash via write-buffer @wbuf. This means that
|
* the last piece of the node won't reach the flash media immediately if it
|
* does not take whole max. write unit (@c->max_write_size). Instead, the node
|
* will sit in RAM until the write-buffer is synchronized (e.g., by timer, or
|
* because more data are appended to the write-buffer).
|
*
|
* This function returns zero in case of success and a negative error code in
|
* case of failure. If the node cannot be written because there is no more
|
* space in this logical eraseblock, %-ENOSPC is returned.
|
*/
|
int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len)
|
{
|
struct ubifs_info *c = wbuf->c;
|
int err, written, n, aligned_len = ALIGN(len, 8);
|
|
dbg_io("%d bytes (%s) to jhead %s wbuf at LEB %d:%d", len,
|
dbg_ntype(((struct ubifs_ch *)buf)->node_type),
|
dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs + wbuf->used);
|
ubifs_assert(len > 0 && wbuf->lnum >= 0 && wbuf->lnum < c->leb_cnt);
|
ubifs_assert(wbuf->offs >= 0 && wbuf->offs % c->min_io_size == 0);
|
ubifs_assert(!(wbuf->offs & 7) && wbuf->offs <= c->leb_size);
|
ubifs_assert(wbuf->avail > 0 && wbuf->avail <= wbuf->size);
|
ubifs_assert(wbuf->size >= c->min_io_size);
|
ubifs_assert(wbuf->size <= c->max_write_size);
|
ubifs_assert(wbuf->size % c->min_io_size == 0);
|
ubifs_assert(mutex_is_locked(&wbuf->io_mutex));
|
ubifs_assert(!c->ro_media && !c->ro_mount);
|
ubifs_assert(!c->space_fixup);
|
if (c->leb_size - wbuf->offs >= c->max_write_size)
|
ubifs_assert(!((wbuf->offs + wbuf->size) % c->max_write_size));
|
|
if (c->leb_size - wbuf->offs - wbuf->used < aligned_len) {
|
err = -ENOSPC;
|
goto out;
|
}
|
|
cancel_wbuf_timer_nolock(wbuf);
|
|
if (c->ro_error)
|
return -EROFS;
|
|
if (aligned_len <= wbuf->avail) {
|
/*
|
* The node is not very large and fits entirely within
|
* write-buffer.
|
*/
|
memcpy(wbuf->buf + wbuf->used, buf, len);
|
|
if (aligned_len == wbuf->avail) {
|
dbg_io("flush jhead %s wbuf to LEB %d:%d",
|
dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs);
|
err = ubifs_leb_write(c, wbuf->lnum, wbuf->buf,
|
wbuf->offs, wbuf->size);
|
if (err)
|
goto out;
|
|
spin_lock(&wbuf->lock);
|
wbuf->offs += wbuf->size;
|
if (c->leb_size - wbuf->offs >= c->max_write_size)
|
wbuf->size = c->max_write_size;
|
else
|
wbuf->size = c->leb_size - wbuf->offs;
|
wbuf->avail = wbuf->size;
|
wbuf->used = 0;
|
wbuf->next_ino = 0;
|
spin_unlock(&wbuf->lock);
|
} else {
|
spin_lock(&wbuf->lock);
|
wbuf->avail -= aligned_len;
|
wbuf->used += aligned_len;
|
spin_unlock(&wbuf->lock);
|
}
|
|
goto exit;
|
}
|
|
written = 0;
|
|
if (wbuf->used) {
|
/*
|
* The node is large enough and does not fit entirely within
|
* current available space. We have to fill and flush
|
* write-buffer and switch to the next max. write unit.
|
*/
|
dbg_io("flush jhead %s wbuf to LEB %d:%d",
|
dbg_jhead(wbuf->jhead), wbuf->lnum, wbuf->offs);
|
memcpy(wbuf->buf + wbuf->used, buf, wbuf->avail);
|
err = ubifs_leb_write(c, wbuf->lnum, wbuf->buf, wbuf->offs,
|
wbuf->size);
|
if (err)
|
goto out;
|
|
wbuf->offs += wbuf->size;
|
len -= wbuf->avail;
|
aligned_len -= wbuf->avail;
|
written += wbuf->avail;
|
} else if (wbuf->offs & (c->max_write_size - 1)) {
|
/*
|
* The write-buffer offset is not aligned to
|
* @c->max_write_size and @wbuf->size is less than
|
* @c->max_write_size. Write @wbuf->size bytes to make sure the
|
* following writes are done in optimal @c->max_write_size
|
* chunks.
|
*/
|
dbg_io("write %d bytes to LEB %d:%d",
|
wbuf->size, wbuf->lnum, wbuf->offs);
|
err = ubifs_leb_write(c, wbuf->lnum, buf, wbuf->offs,
|
wbuf->size);
|
if (err)
|
goto out;
|
|
wbuf->offs += wbuf->size;
|
len -= wbuf->size;
|
aligned_len -= wbuf->size;
|
written += wbuf->size;
|
}
|
|
/*
|
* The remaining data may take more whole max. write units, so write the
|
* remains multiple to max. write unit size directly to the flash media.
|
* We align node length to 8-byte boundary because we anyway flash wbuf
|
* if the remaining space is less than 8 bytes.
|
*/
|
n = aligned_len >> c->max_write_shift;
|
if (n) {
|
n <<= c->max_write_shift;
|
dbg_io("write %d bytes to LEB %d:%d", n, wbuf->lnum,
|
wbuf->offs);
|
err = ubifs_leb_write(c, wbuf->lnum, buf + written,
|
wbuf->offs, n);
|
if (err)
|
goto out;
|
wbuf->offs += n;
|
aligned_len -= n;
|
len -= n;
|
written += n;
|
}
|
|
spin_lock(&wbuf->lock);
|
if (aligned_len)
|
/*
|
* And now we have what's left and what does not take whole
|
* max. write unit, so write it to the write-buffer and we are
|
* done.
|
*/
|
memcpy(wbuf->buf, buf + written, len);
|
|
if (c->leb_size - wbuf->offs >= c->max_write_size)
|
wbuf->size = c->max_write_size;
|
else
|
wbuf->size = c->leb_size - wbuf->offs;
|
wbuf->avail = wbuf->size - aligned_len;
|
wbuf->used = aligned_len;
|
wbuf->next_ino = 0;
|
spin_unlock(&wbuf->lock);
|
|
exit:
|
if (wbuf->sync_callback) {
|
int free = c->leb_size - wbuf->offs - wbuf->used;
|
|
err = wbuf->sync_callback(c, wbuf->lnum, free, 0);
|
if (err)
|
goto out;
|
}
|
|
if (wbuf->used)
|
new_wbuf_timer_nolock(wbuf);
|
|
return 0;
|
|
out:
|
ubifs_err(c, "cannot write %d bytes to LEB %d:%d, error %d",
|
len, wbuf->lnum, wbuf->offs, err);
|
ubifs_dump_node(c, buf);
|
dump_stack();
|
ubifs_dump_leb(c, wbuf->lnum);
|
return err;
|
}
|
|
/**
|
* ubifs_write_node - write node to the media.
|
* @c: UBIFS file-system description object
|
* @buf: the node to write
|
* @len: node length
|
* @lnum: logical eraseblock number
|
* @offs: offset within the logical eraseblock
|
*
|
* This function automatically fills node magic number, assigns sequence
|
* number, and calculates node CRC checksum. The length of the @buf buffer has
|
* to be aligned to the minimal I/O unit size. This function automatically
|
* appends padding node and padding bytes if needed. Returns zero in case of
|
* success and a negative error code in case of failure.
|
*/
|
int ubifs_write_node(struct ubifs_info *c, void *buf, int len, int lnum,
|
int offs)
|
{
|
int err, buf_len = ALIGN(len, c->min_io_size);
|
|
dbg_io("LEB %d:%d, %s, length %d (aligned %d)",
|
lnum, offs, dbg_ntype(((struct ubifs_ch *)buf)->node_type), len,
|
buf_len);
|
ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
|
ubifs_assert(offs % c->min_io_size == 0 && offs < c->leb_size);
|
ubifs_assert(!c->ro_media && !c->ro_mount);
|
ubifs_assert(!c->space_fixup);
|
|
if (c->ro_error)
|
return -EROFS;
|
|
ubifs_prepare_node(c, buf, len, 1);
|
err = ubifs_leb_write(c, lnum, buf, offs, buf_len);
|
if (err)
|
ubifs_dump_node(c, buf);
|
|
return err;
|
}
|
#endif
|
|
/**
|
* ubifs_read_node_wbuf - read node from the media or write-buffer.
|
* @wbuf: wbuf to check for un-written data
|
* @buf: buffer to read to
|
* @type: node type
|
* @len: node length
|
* @lnum: logical eraseblock number
|
* @offs: offset within the logical eraseblock
|
*
|
* This function reads a node of known type and length, checks it and stores
|
* in @buf. If the node partially or fully sits in the write-buffer, this
|
* function takes data from the buffer, otherwise it reads the flash media.
|
* Returns zero in case of success, %-EUCLEAN if CRC mismatched and a negative
|
* error code in case of failure.
|
*/
|
int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
|
int lnum, int offs)
|
{
|
const struct ubifs_info *c = wbuf->c;
|
int err, rlen, overlap;
|
struct ubifs_ch *ch = buf;
|
|
dbg_io("LEB %d:%d, %s, length %d, jhead %s", lnum, offs,
|
dbg_ntype(type), len, dbg_jhead(wbuf->jhead));
|
ubifs_assert(wbuf && lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
|
ubifs_assert(!(offs & 7) && offs < c->leb_size);
|
ubifs_assert(type >= 0 && type < UBIFS_NODE_TYPES_CNT);
|
|
spin_lock(&wbuf->lock);
|
overlap = (lnum == wbuf->lnum && offs + len > wbuf->offs);
|
if (!overlap) {
|
/* We may safely unlock the write-buffer and read the data */
|
spin_unlock(&wbuf->lock);
|
return ubifs_read_node(c, buf, type, len, lnum, offs);
|
}
|
|
/* Don't read under wbuf */
|
rlen = wbuf->offs - offs;
|
if (rlen < 0)
|
rlen = 0;
|
|
/* Copy the rest from the write-buffer */
|
memcpy(buf + rlen, wbuf->buf + offs + rlen - wbuf->offs, len - rlen);
|
spin_unlock(&wbuf->lock);
|
|
if (rlen > 0) {
|
/* Read everything that goes before write-buffer */
|
err = ubifs_leb_read(c, lnum, buf, offs, rlen, 0);
|
if (err && err != -EBADMSG)
|
return err;
|
}
|
|
if (type != ch->node_type) {
|
ubifs_err(c, "bad node type (%d but expected %d)",
|
ch->node_type, type);
|
goto out;
|
}
|
|
err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
|
if (err) {
|
ubifs_err(c, "expected node type %d", type);
|
return err;
|
}
|
|
rlen = le32_to_cpu(ch->len);
|
if (rlen != len) {
|
ubifs_err(c, "bad node length %d, expected %d", rlen, len);
|
goto out;
|
}
|
|
return 0;
|
|
out:
|
ubifs_err(c, "bad node at LEB %d:%d", lnum, offs);
|
ubifs_dump_node(c, buf);
|
dump_stack();
|
return -EINVAL;
|
}
|
|
/**
|
* ubifs_read_node - read node.
|
* @c: UBIFS file-system description object
|
* @buf: buffer to read to
|
* @type: node type
|
* @len: node length (not aligned)
|
* @lnum: logical eraseblock number
|
* @offs: offset within the logical eraseblock
|
*
|
* This function reads a node of known type and and length, checks it and
|
* stores in @buf. Returns zero in case of success, %-EUCLEAN if CRC mismatched
|
* and a negative error code in case of failure.
|
*/
|
int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
|
int lnum, int offs)
|
{
|
int err, l;
|
struct ubifs_ch *ch = buf;
|
|
dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len);
|
ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
|
ubifs_assert(len >= UBIFS_CH_SZ && offs + len <= c->leb_size);
|
ubifs_assert(!(offs & 7) && offs < c->leb_size);
|
ubifs_assert(type >= 0 && type < UBIFS_NODE_TYPES_CNT);
|
|
err = ubifs_leb_read(c, lnum, buf, offs, len, 0);
|
if (err && err != -EBADMSG)
|
return err;
|
|
if (type != ch->node_type) {
|
ubifs_errc(c, "bad node type (%d but expected %d)",
|
ch->node_type, type);
|
goto out;
|
}
|
|
err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
|
if (err) {
|
ubifs_errc(c, "expected node type %d", type);
|
return err;
|
}
|
|
l = le32_to_cpu(ch->len);
|
if (l != len) {
|
ubifs_errc(c, "bad node length %d, expected %d", l, len);
|
goto out;
|
}
|
|
return 0;
|
|
out:
|
ubifs_errc(c, "bad node at LEB %d:%d, LEB mapping status %d", lnum,
|
offs, ubi_is_mapped(c->ubi, lnum));
|
if (!c->probing) {
|
ubifs_dump_node(c, buf);
|
dump_stack();
|
}
|
return -EINVAL;
|
}
|
|
/**
|
* ubifs_wbuf_init - initialize write-buffer.
|
* @c: UBIFS file-system description object
|
* @wbuf: write-buffer to initialize
|
*
|
* This function initializes write-buffer. Returns zero in case of success
|
* %-ENOMEM in case of failure.
|
*/
|
int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf)
|
{
|
size_t size;
|
|
wbuf->buf = kmalloc(c->max_write_size, GFP_KERNEL);
|
if (!wbuf->buf)
|
return -ENOMEM;
|
|
size = (c->max_write_size / UBIFS_CH_SZ + 1) * sizeof(ino_t);
|
wbuf->inodes = kmalloc(size, GFP_KERNEL);
|
if (!wbuf->inodes) {
|
kfree(wbuf->buf);
|
wbuf->buf = NULL;
|
return -ENOMEM;
|
}
|
|
wbuf->used = 0;
|
wbuf->lnum = wbuf->offs = -1;
|
/*
|
* If the LEB starts at the max. write size aligned address, then
|
* write-buffer size has to be set to @c->max_write_size. Otherwise,
|
* set it to something smaller so that it ends at the closest max.
|
* write size boundary.
|
*/
|
size = c->max_write_size - (c->leb_start % c->max_write_size);
|
wbuf->avail = wbuf->size = size;
|
wbuf->sync_callback = NULL;
|
mutex_init(&wbuf->io_mutex);
|
spin_lock_init(&wbuf->lock);
|
wbuf->c = c;
|
wbuf->next_ino = 0;
|
|
#ifndef __UBOOT__
|
hrtimer_init(&wbuf->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
|
wbuf->timer.function = wbuf_timer_callback_nolock;
|
wbuf->softlimit = ktime_set(WBUF_TIMEOUT_SOFTLIMIT, 0);
|
wbuf->delta = WBUF_TIMEOUT_HARDLIMIT - WBUF_TIMEOUT_SOFTLIMIT;
|
wbuf->delta *= 1000000000ULL;
|
ubifs_assert(wbuf->delta <= ULONG_MAX);
|
#endif
|
return 0;
|
}
|
|
/**
|
* ubifs_wbuf_add_ino_nolock - add an inode number into the wbuf inode array.
|
* @wbuf: the write-buffer where to add
|
* @inum: the inode number
|
*
|
* This function adds an inode number to the inode array of the write-buffer.
|
*/
|
void ubifs_wbuf_add_ino_nolock(struct ubifs_wbuf *wbuf, ino_t inum)
|
{
|
if (!wbuf->buf)
|
/* NOR flash or something similar */
|
return;
|
|
spin_lock(&wbuf->lock);
|
if (wbuf->used)
|
wbuf->inodes[wbuf->next_ino++] = inum;
|
spin_unlock(&wbuf->lock);
|
}
|
|
/**
|
* wbuf_has_ino - returns if the wbuf contains data from the inode.
|
* @wbuf: the write-buffer
|
* @inum: the inode number
|
*
|
* This function returns with %1 if the write-buffer contains some data from the
|
* given inode otherwise it returns with %0.
|
*/
|
static int wbuf_has_ino(struct ubifs_wbuf *wbuf, ino_t inum)
|
{
|
int i, ret = 0;
|
|
spin_lock(&wbuf->lock);
|
for (i = 0; i < wbuf->next_ino; i++)
|
if (inum == wbuf->inodes[i]) {
|
ret = 1;
|
break;
|
}
|
spin_unlock(&wbuf->lock);
|
|
return ret;
|
}
|
|
/**
|
* ubifs_sync_wbufs_by_inode - synchronize write-buffers for an inode.
|
* @c: UBIFS file-system description object
|
* @inode: inode to synchronize
|
*
|
* This function synchronizes write-buffers which contain nodes belonging to
|
* @inode. Returns zero in case of success and a negative error code in case of
|
* failure.
|
*/
|
int ubifs_sync_wbufs_by_inode(struct ubifs_info *c, struct inode *inode)
|
{
|
int i, err = 0;
|
|
for (i = 0; i < c->jhead_cnt; i++) {
|
struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
|
|
if (i == GCHD)
|
/*
|
* GC head is special, do not look at it. Even if the
|
* head contains something related to this inode, it is
|
* a _copy_ of corresponding on-flash node which sits
|
* somewhere else.
|
*/
|
continue;
|
|
if (!wbuf_has_ino(wbuf, inode->i_ino))
|
continue;
|
|
mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
|
if (wbuf_has_ino(wbuf, inode->i_ino))
|
err = ubifs_wbuf_sync_nolock(wbuf);
|
mutex_unlock(&wbuf->io_mutex);
|
|
if (err) {
|
ubifs_ro_mode(c, err);
|
return err;
|
}
|
}
|
return 0;
|
}
|
