linux/fs/ubifs/lpt_commit.c

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/*
* 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: Adrian Hunter
* Artem Bityutskiy (Битюцкий Артём)
*/
/*
* This file implements commit-related functionality of the LEB properties
* subsystem.
*/
#include <linux/crc16.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include "ubifs.h"
#ifdef CONFIG_UBIFS_FS_DEBUG
static int dbg_populate_lsave(struct ubifs_info *c);
#else
#define dbg_populate_lsave(c) 0
#endif
/**
* first_dirty_cnode - find first dirty cnode.
* @c: UBIFS file-system description object
* @nnode: nnode at which to start
*
* This function returns the first dirty cnode or %NULL if there is not one.
*/
static struct ubifs_cnode *first_dirty_cnode(struct ubifs_nnode *nnode)
{
ubifs_assert(nnode);
while (1) {
int i, cont = 0;
for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
struct ubifs_cnode *cnode;
cnode = nnode->nbranch[i].cnode;
if (cnode &&
test_bit(DIRTY_CNODE, &cnode->flags)) {
if (cnode->level == 0)
return cnode;
nnode = (struct ubifs_nnode *)cnode;
cont = 1;
break;
}
}
if (!cont)
return (struct ubifs_cnode *)nnode;
}
}
/**
* next_dirty_cnode - find next dirty cnode.
* @cnode: cnode from which to begin searching
*
* This function returns the next dirty cnode or %NULL if there is not one.
*/
static struct ubifs_cnode *next_dirty_cnode(struct ubifs_cnode *cnode)
{
struct ubifs_nnode *nnode;
int i;
ubifs_assert(cnode);
nnode = cnode->parent;
if (!nnode)
return NULL;
for (i = cnode->iip + 1; i < UBIFS_LPT_FANOUT; i++) {
cnode = nnode->nbranch[i].cnode;
if (cnode && test_bit(DIRTY_CNODE, &cnode->flags)) {
if (cnode->level == 0)
return cnode; /* cnode is a pnode */
/* cnode is a nnode */
return first_dirty_cnode((struct ubifs_nnode *)cnode);
}
}
return (struct ubifs_cnode *)nnode;
}
/**
* get_cnodes_to_commit - create list of dirty cnodes to commit.
* @c: UBIFS file-system description object
*
* This function returns the number of cnodes to commit.
*/
static int get_cnodes_to_commit(struct ubifs_info *c)
{
struct ubifs_cnode *cnode, *cnext;
int cnt = 0;
if (!c->nroot)
return 0;
if (!test_bit(DIRTY_CNODE, &c->nroot->flags))
return 0;
c->lpt_cnext = first_dirty_cnode(c->nroot);
cnode = c->lpt_cnext;
if (!cnode)
return 0;
cnt += 1;
while (1) {
ubifs_assert(!test_bit(COW_ZNODE, &cnode->flags));
__set_bit(COW_ZNODE, &cnode->flags);
cnext = next_dirty_cnode(cnode);
if (!cnext) {
cnode->cnext = c->lpt_cnext;
break;
}
cnode->cnext = cnext;
cnode = cnext;
cnt += 1;
}
dbg_cmt("committing %d cnodes", cnt);
dbg_lp("committing %d cnodes", cnt);
ubifs_assert(cnt == c->dirty_nn_cnt + c->dirty_pn_cnt);
return cnt;
}
/**
* upd_ltab - update LPT LEB properties.
* @c: UBIFS file-system description object
* @lnum: LEB number
* @free: amount of free space
* @dirty: amount of dirty space to add
*/
static void upd_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
{
dbg_lp("LEB %d free %d dirty %d to %d +%d",
lnum, c->ltab[lnum - c->lpt_first].free,
c->ltab[lnum - c->lpt_first].dirty, free, dirty);
ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
c->ltab[lnum - c->lpt_first].free = free;
c->ltab[lnum - c->lpt_first].dirty += dirty;
}
/**
* alloc_lpt_leb - allocate an LPT LEB that is empty.
* @c: UBIFS file-system description object
* @lnum: LEB number is passed and returned here
*
* This function finds the next empty LEB in the ltab starting from @lnum. If a
* an empty LEB is found it is returned in @lnum and the function returns %0.
* Otherwise the function returns -ENOSPC. Note however, that LPT is designed
* never to run out of space.
*/
static int alloc_lpt_leb(struct ubifs_info *c, int *lnum)
{
int i, n;
n = *lnum - c->lpt_first + 1;
for (i = n; i < c->lpt_lebs; i++) {
if (c->ltab[i].tgc || c->ltab[i].cmt)
continue;
if (c->ltab[i].free == c->leb_size) {
c->ltab[i].cmt = 1;
*lnum = i + c->lpt_first;
return 0;
}
}
for (i = 0; i < n; i++) {
if (c->ltab[i].tgc || c->ltab[i].cmt)
continue;
if (c->ltab[i].free == c->leb_size) {
c->ltab[i].cmt = 1;
*lnum = i + c->lpt_first;
return 0;
}
}
return -ENOSPC;
}
/**
* layout_cnodes - layout cnodes for commit.
* @c: UBIFS file-system description object
*
* This function returns %0 on success and a negative error code on failure.
*/
static int layout_cnodes(struct ubifs_info *c)
{
int lnum, offs, len, alen, done_lsave, done_ltab, err;
struct ubifs_cnode *cnode;
err = dbg_chk_lpt_sz(c, 0, 0);
if (err)
return err;
cnode = c->lpt_cnext;
if (!cnode)
return 0;
lnum = c->nhead_lnum;
offs = c->nhead_offs;
/* Try to place lsave and ltab nicely */
done_lsave = !c->big_lpt;
done_ltab = 0;
if (!done_lsave && offs + c->lsave_sz <= c->leb_size) {
done_lsave = 1;
c->lsave_lnum = lnum;
c->lsave_offs = offs;
offs += c->lsave_sz;
dbg_chk_lpt_sz(c, 1, c->lsave_sz);
}
if (offs + c->ltab_sz <= c->leb_size) {
done_ltab = 1;
c->ltab_lnum = lnum;
c->ltab_offs = offs;
offs += c->ltab_sz;
dbg_chk_lpt_sz(c, 1, c->ltab_sz);
}
do {
if (cnode->level) {
len = c->nnode_sz;
c->dirty_nn_cnt -= 1;
} else {
len = c->pnode_sz;
c->dirty_pn_cnt -= 1;
}
while (offs + len > c->leb_size) {
alen = ALIGN(offs, c->min_io_size);
upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
err = alloc_lpt_leb(c, &lnum);
if (err)
goto no_space;
offs = 0;
ubifs_assert(lnum >= c->lpt_first &&
lnum <= c->lpt_last);
/* Try to place lsave and ltab nicely */
if (!done_lsave) {
done_lsave = 1;
c->lsave_lnum = lnum;
c->lsave_offs = offs;
offs += c->lsave_sz;
dbg_chk_lpt_sz(c, 1, c->lsave_sz);
continue;
}
if (!done_ltab) {
done_ltab = 1;
c->ltab_lnum = lnum;
c->ltab_offs = offs;
offs += c->ltab_sz;
dbg_chk_lpt_sz(c, 1, c->ltab_sz);
continue;
}
break;
}
if (cnode->parent) {
cnode->parent->nbranch[cnode->iip].lnum = lnum;
cnode->parent->nbranch[cnode->iip].offs = offs;
} else {
c->lpt_lnum = lnum;
c->lpt_offs = offs;
}
offs += len;
dbg_chk_lpt_sz(c, 1, len);
cnode = cnode->cnext;
} while (cnode && cnode != c->lpt_cnext);
/* Make sure to place LPT's save table */
if (!done_lsave) {
if (offs + c->lsave_sz > c->leb_size) {
alen = ALIGN(offs, c->min_io_size);
upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
err = alloc_lpt_leb(c, &lnum);
if (err)
goto no_space;
offs = 0;
ubifs_assert(lnum >= c->lpt_first &&
lnum <= c->lpt_last);
}
done_lsave = 1;
c->lsave_lnum = lnum;
c->lsave_offs = offs;
offs += c->lsave_sz;
dbg_chk_lpt_sz(c, 1, c->lsave_sz);
}
/* Make sure to place LPT's own lprops table */
if (!done_ltab) {
if (offs + c->ltab_sz > c->leb_size) {
alen = ALIGN(offs, c->min_io_size);
upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
err = alloc_lpt_leb(c, &lnum);
if (err)
goto no_space;
offs = 0;
ubifs_assert(lnum >= c->lpt_first &&
lnum <= c->lpt_last);
}
done_ltab = 1;
c->ltab_lnum = lnum;
c->ltab_offs = offs;
offs += c->ltab_sz;
dbg_chk_lpt_sz(c, 1, c->ltab_sz);
}
alen = ALIGN(offs, c->min_io_size);
upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
dbg_chk_lpt_sz(c, 4, alen - offs);
err = dbg_chk_lpt_sz(c, 3, alen);
if (err)
return err;
return 0;
no_space:
ubifs_err("LPT out of space");
dbg_err("LPT out of space at LEB %d:%d needing %d, done_ltab %d, "
"done_lsave %d", lnum, offs, len, done_ltab, done_lsave);
dbg_dump_lpt_info(c);
dbg_dump_lpt_lebs(c);
dump_stack();
return err;
}
/**
* realloc_lpt_leb - allocate an LPT LEB that is empty.
* @c: UBIFS file-system description object
* @lnum: LEB number is passed and returned here
*
* This function duplicates exactly the results of the function alloc_lpt_leb.
* It is used during end commit to reallocate the same LEB numbers that were
* allocated by alloc_lpt_leb during start commit.
*
* This function finds the next LEB that was allocated by the alloc_lpt_leb
* function starting from @lnum. If a LEB is found it is returned in @lnum and
* the function returns %0. Otherwise the function returns -ENOSPC.
* Note however, that LPT is designed never to run out of space.
*/
static int realloc_lpt_leb(struct ubifs_info *c, int *lnum)
{
int i, n;
n = *lnum - c->lpt_first + 1;
for (i = n; i < c->lpt_lebs; i++)
if (c->ltab[i].cmt) {
c->ltab[i].cmt = 0;
*lnum = i + c->lpt_first;
return 0;
}
for (i = 0; i < n; i++)
if (c->ltab[i].cmt) {
c->ltab[i].cmt = 0;
*lnum = i + c->lpt_first;
return 0;
}
return -ENOSPC;
}
/**
* write_cnodes - write cnodes for commit.
* @c: UBIFS file-system description object
*
* This function returns %0 on success and a negative error code on failure.
*/
static int write_cnodes(struct ubifs_info *c)
{
int lnum, offs, len, from, err, wlen, alen, done_ltab, done_lsave;
struct ubifs_cnode *cnode;
void *buf = c->lpt_buf;
cnode = c->lpt_cnext;
if (!cnode)
return 0;
lnum = c->nhead_lnum;
offs = c->nhead_offs;
from = offs;
/* Ensure empty LEB is unmapped */
if (offs == 0) {
err = ubifs_leb_unmap(c, lnum);
if (err)
return err;
}
/* Try to place lsave and ltab nicely */
done_lsave = !c->big_lpt;
done_ltab = 0;
if (!done_lsave && offs + c->lsave_sz <= c->leb_size) {
done_lsave = 1;
ubifs_pack_lsave(c, buf + offs, c->lsave);
offs += c->lsave_sz;
dbg_chk_lpt_sz(c, 1, c->lsave_sz);
}
if (offs + c->ltab_sz <= c->leb_size) {
done_ltab = 1;
ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
offs += c->ltab_sz;
dbg_chk_lpt_sz(c, 1, c->ltab_sz);
}
/* Loop for each cnode */
do {
if (cnode->level)
len = c->nnode_sz;
else
len = c->pnode_sz;
while (offs + len > c->leb_size) {
wlen = offs - from;
if (wlen) {
alen = ALIGN(wlen, c->min_io_size);
memset(buf + offs, 0xff, alen - wlen);
err = ubifs_leb_write(c, lnum, buf + from, from,
alen, UBI_SHORTTERM);
if (err)
return err;
}
dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
err = realloc_lpt_leb(c, &lnum);
if (err)
goto no_space;
2009-03-14 22:35:27 +08:00
offs = from = 0;
ubifs_assert(lnum >= c->lpt_first &&
lnum <= c->lpt_last);
err = ubifs_leb_unmap(c, lnum);
if (err)
return err;
/* Try to place lsave and ltab nicely */
if (!done_lsave) {
done_lsave = 1;
ubifs_pack_lsave(c, buf + offs, c->lsave);
offs += c->lsave_sz;
dbg_chk_lpt_sz(c, 1, c->lsave_sz);
continue;
}
if (!done_ltab) {
done_ltab = 1;
ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
offs += c->ltab_sz;
dbg_chk_lpt_sz(c, 1, c->ltab_sz);
continue;
}
break;
}
if (cnode->level)
ubifs_pack_nnode(c, buf + offs,
(struct ubifs_nnode *)cnode);
else
ubifs_pack_pnode(c, buf + offs,
(struct ubifs_pnode *)cnode);
/*
* The reason for the barriers is the same as in case of TNC.
* See comment in 'write_index()'. 'dirty_cow_nnode()' and
* 'dirty_cow_pnode()' are the functions for which this is
* important.
*/
clear_bit(DIRTY_CNODE, &cnode->flags);
smp_mb__before_clear_bit();
clear_bit(COW_ZNODE, &cnode->flags);
smp_mb__after_clear_bit();
offs += len;
dbg_chk_lpt_sz(c, 1, len);
cnode = cnode->cnext;
} while (cnode && cnode != c->lpt_cnext);
/* Make sure to place LPT's save table */
if (!done_lsave) {
if (offs + c->lsave_sz > c->leb_size) {
wlen = offs - from;
alen = ALIGN(wlen, c->min_io_size);
memset(buf + offs, 0xff, alen - wlen);
err = ubifs_leb_write(c, lnum, buf + from, from, alen,
UBI_SHORTTERM);
if (err)
return err;
dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
err = realloc_lpt_leb(c, &lnum);
if (err)
goto no_space;
2009-03-14 22:35:27 +08:00
offs = from = 0;
ubifs_assert(lnum >= c->lpt_first &&
lnum <= c->lpt_last);
err = ubifs_leb_unmap(c, lnum);
if (err)
return err;
}
done_lsave = 1;
ubifs_pack_lsave(c, buf + offs, c->lsave);
offs += c->lsave_sz;
dbg_chk_lpt_sz(c, 1, c->lsave_sz);
}
/* Make sure to place LPT's own lprops table */
if (!done_ltab) {
if (offs + c->ltab_sz > c->leb_size) {
wlen = offs - from;
alen = ALIGN(wlen, c->min_io_size);
memset(buf + offs, 0xff, alen - wlen);
err = ubifs_leb_write(c, lnum, buf + from, from, alen,
UBI_SHORTTERM);
if (err)
return err;
dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
err = realloc_lpt_leb(c, &lnum);
if (err)
goto no_space;
2009-03-14 22:35:27 +08:00
offs = from = 0;
ubifs_assert(lnum >= c->lpt_first &&
lnum <= c->lpt_last);
err = ubifs_leb_unmap(c, lnum);
if (err)
return err;
}
done_ltab = 1;
ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
offs += c->ltab_sz;
dbg_chk_lpt_sz(c, 1, c->ltab_sz);
}
/* Write remaining data in buffer */
wlen = offs - from;
alen = ALIGN(wlen, c->min_io_size);
memset(buf + offs, 0xff, alen - wlen);
err = ubifs_leb_write(c, lnum, buf + from, from, alen, UBI_SHORTTERM);
if (err)
return err;
dbg_chk_lpt_sz(c, 4, alen - wlen);
err = dbg_chk_lpt_sz(c, 3, ALIGN(offs, c->min_io_size));
if (err)
return err;
c->nhead_lnum = lnum;
c->nhead_offs = ALIGN(offs, c->min_io_size);
dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
if (c->big_lpt)
dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
return 0;
no_space:
ubifs_err("LPT out of space mismatch");
dbg_err("LPT out of space mismatch at LEB %d:%d needing %d, done_ltab "
"%d, done_lsave %d", lnum, offs, len, done_ltab, done_lsave);
dbg_dump_lpt_info(c);
dbg_dump_lpt_lebs(c);
dump_stack();
return err;
}
/**
* next_pnode_to_dirty - find next pnode to dirty.
* @c: UBIFS file-system description object
* @pnode: pnode
*
* This function returns the next pnode to dirty or %NULL if there are no more
* pnodes. Note that pnodes that have never been written (lnum == 0) are
* skipped.
*/
static struct ubifs_pnode *next_pnode_to_dirty(struct ubifs_info *c,
struct ubifs_pnode *pnode)
{
struct ubifs_nnode *nnode;
int iip;
/* Try to go right */
nnode = pnode->parent;
for (iip = pnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) {
if (nnode->nbranch[iip].lnum)
return ubifs_get_pnode(c, nnode, iip);
}
/* Go up while can't go right */
do {
iip = nnode->iip + 1;
nnode = nnode->parent;
if (!nnode)
return NULL;
for (; iip < UBIFS_LPT_FANOUT; iip++) {
if (nnode->nbranch[iip].lnum)
break;
}
} while (iip >= UBIFS_LPT_FANOUT);
/* Go right */
nnode = ubifs_get_nnode(c, nnode, iip);
if (IS_ERR(nnode))
return (void *)nnode;
/* Go down to level 1 */
while (nnode->level > 1) {
for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++) {
if (nnode->nbranch[iip].lnum)
break;
}
if (iip >= UBIFS_LPT_FANOUT) {
/*
* Should not happen, but we need to keep going
* if it does.
*/
iip = 0;
}
nnode = ubifs_get_nnode(c, nnode, iip);
if (IS_ERR(nnode))
return (void *)nnode;
}
for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++)
if (nnode->nbranch[iip].lnum)
break;
if (iip >= UBIFS_LPT_FANOUT)
/* Should not happen, but we need to keep going if it does */
iip = 0;
return ubifs_get_pnode(c, nnode, iip);
}
/**
* pnode_lookup - lookup a pnode in the LPT.
* @c: UBIFS file-system description object
* @i: pnode number (0 to main_lebs - 1)
*
* This function returns a pointer to the pnode on success or a negative
* error code on failure.
*/
static struct ubifs_pnode *pnode_lookup(struct ubifs_info *c, int i)
{
int err, h, iip, shft;
struct ubifs_nnode *nnode;
if (!c->nroot) {
err = ubifs_read_nnode(c, NULL, 0);
if (err)
return ERR_PTR(err);
}
i <<= UBIFS_LPT_FANOUT_SHIFT;
nnode = c->nroot;
shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
for (h = 1; h < c->lpt_hght; h++) {
iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
shft -= UBIFS_LPT_FANOUT_SHIFT;
nnode = ubifs_get_nnode(c, nnode, iip);
if (IS_ERR(nnode))
return ERR_CAST(nnode);
}
iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
return ubifs_get_pnode(c, nnode, iip);
}
/**
* add_pnode_dirt - add dirty space to LPT LEB properties.
* @c: UBIFS file-system description object
* @pnode: pnode for which to add dirt
*/
static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
{
ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
c->pnode_sz);
}
/**
* do_make_pnode_dirty - mark a pnode dirty.
* @c: UBIFS file-system description object
* @pnode: pnode to mark dirty
*/
static void do_make_pnode_dirty(struct ubifs_info *c, struct ubifs_pnode *pnode)
{
/* Assumes cnext list is empty i.e. not called during commit */
if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
struct ubifs_nnode *nnode;
c->dirty_pn_cnt += 1;
add_pnode_dirt(c, pnode);
/* Mark parent and ancestors dirty too */
nnode = pnode->parent;
while (nnode) {
if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
c->dirty_nn_cnt += 1;
ubifs_add_nnode_dirt(c, nnode);
nnode = nnode->parent;
} else
break;
}
}
}
/**
* make_tree_dirty - mark the entire LEB properties tree dirty.
* @c: UBIFS file-system description object
*
* This function is used by the "small" LPT model to cause the entire LEB
* properties tree to be written. The "small" LPT model does not use LPT
* garbage collection because it is more efficient to write the entire tree
* (because it is small).
*
* This function returns %0 on success and a negative error code on failure.
*/
static int make_tree_dirty(struct ubifs_info *c)
{
struct ubifs_pnode *pnode;
pnode = pnode_lookup(c, 0);
if (IS_ERR(pnode))
return PTR_ERR(pnode);
while (pnode) {
do_make_pnode_dirty(c, pnode);
pnode = next_pnode_to_dirty(c, pnode);
if (IS_ERR(pnode))
return PTR_ERR(pnode);
}
return 0;
}
/**
* need_write_all - determine if the LPT area is running out of free space.
* @c: UBIFS file-system description object
*
* This function returns %1 if the LPT area is running out of free space and %0
* if it is not.
*/
static int need_write_all(struct ubifs_info *c)
{
long long free = 0;
int i;
for (i = 0; i < c->lpt_lebs; i++) {
if (i + c->lpt_first == c->nhead_lnum)
free += c->leb_size - c->nhead_offs;
else if (c->ltab[i].free == c->leb_size)
free += c->leb_size;
else if (c->ltab[i].free + c->ltab[i].dirty == c->leb_size)
free += c->leb_size;
}
/* Less than twice the size left */
if (free <= c->lpt_sz * 2)
return 1;
return 0;
}
/**
* lpt_tgc_start - start trivial garbage collection of LPT LEBs.
* @c: UBIFS file-system description object
*
* LPT trivial garbage collection is where a LPT LEB contains only dirty and
* free space and so may be reused as soon as the next commit is completed.
* This function is called during start commit to mark LPT LEBs for trivial GC.
*/
static void lpt_tgc_start(struct ubifs_info *c)
{
int i;
for (i = 0; i < c->lpt_lebs; i++) {
if (i + c->lpt_first == c->nhead_lnum)
continue;
if (c->ltab[i].dirty > 0 &&
c->ltab[i].free + c->ltab[i].dirty == c->leb_size) {
c->ltab[i].tgc = 1;
c->ltab[i].free = c->leb_size;
c->ltab[i].dirty = 0;
dbg_lp("LEB %d", i + c->lpt_first);
}
}
}
/**
* lpt_tgc_end - end trivial garbage collection of LPT LEBs.
* @c: UBIFS file-system description object
*
* LPT trivial garbage collection is where a LPT LEB contains only dirty and
* free space and so may be reused as soon as the next commit is completed.
* This function is called after the commit is completed (master node has been
* written) and un-maps LPT LEBs that were marked for trivial GC.
*/
static int lpt_tgc_end(struct ubifs_info *c)
{
int i, err;
for (i = 0; i < c->lpt_lebs; i++)
if (c->ltab[i].tgc) {
err = ubifs_leb_unmap(c, i + c->lpt_first);
if (err)
return err;
c->ltab[i].tgc = 0;
dbg_lp("LEB %d", i + c->lpt_first);
}
return 0;
}
/**
* populate_lsave - fill the lsave array with important LEB numbers.
* @c: the UBIFS file-system description object
*
* This function is only called for the "big" model. It records a small number
* of LEB numbers of important LEBs. Important LEBs are ones that are (from
* most important to least important): empty, freeable, freeable index, dirty
* index, dirty or free. Upon mount, we read this list of LEB numbers and bring
* their pnodes into memory. That will stop us from having to scan the LPT
* straight away. For the "small" model we assume that scanning the LPT is no
* big deal.
*/
static void populate_lsave(struct ubifs_info *c)
{
struct ubifs_lprops *lprops;
struct ubifs_lpt_heap *heap;
int i, cnt = 0;
ubifs_assert(c->big_lpt);
if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) {
c->lpt_drty_flgs |= LSAVE_DIRTY;
ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz);
}
if (dbg_populate_lsave(c))
return;
list_for_each_entry(lprops, &c->empty_list, list) {
c->lsave[cnt++] = lprops->lnum;
if (cnt >= c->lsave_cnt)
return;
}
list_for_each_entry(lprops, &c->freeable_list, list) {
c->lsave[cnt++] = lprops->lnum;
if (cnt >= c->lsave_cnt)
return;
}
list_for_each_entry(lprops, &c->frdi_idx_list, list) {
c->lsave[cnt++] = lprops->lnum;
if (cnt >= c->lsave_cnt)
return;
}
heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
for (i = 0; i < heap->cnt; i++) {
c->lsave[cnt++] = heap->arr[i]->lnum;
if (cnt >= c->lsave_cnt)
return;
}
heap = &c->lpt_heap[LPROPS_DIRTY - 1];
for (i = 0; i < heap->cnt; i++) {
c->lsave[cnt++] = heap->arr[i]->lnum;
if (cnt >= c->lsave_cnt)
return;
}
heap = &c->lpt_heap[LPROPS_FREE - 1];
for (i = 0; i < heap->cnt; i++) {
c->lsave[cnt++] = heap->arr[i]->lnum;
if (cnt >= c->lsave_cnt)
return;
}
/* Fill it up completely */
while (cnt < c->lsave_cnt)
c->lsave[cnt++] = c->main_first;
}
/**
* nnode_lookup - lookup a nnode in the LPT.
* @c: UBIFS file-system description object
* @i: nnode number
*
* This function returns a pointer to the nnode on success or a negative
* error code on failure.
*/
static struct ubifs_nnode *nnode_lookup(struct ubifs_info *c, int i)
{
int err, iip;
struct ubifs_nnode *nnode;
if (!c->nroot) {
err = ubifs_read_nnode(c, NULL, 0);
if (err)
return ERR_PTR(err);
}
nnode = c->nroot;
while (1) {
iip = i & (UBIFS_LPT_FANOUT - 1);
i >>= UBIFS_LPT_FANOUT_SHIFT;
if (!i)
break;
nnode = ubifs_get_nnode(c, nnode, iip);
if (IS_ERR(nnode))
return nnode;
}
return nnode;
}
/**
* make_nnode_dirty - find a nnode and, if found, make it dirty.
* @c: UBIFS file-system description object
* @node_num: nnode number of nnode to make dirty
* @lnum: LEB number where nnode was written
* @offs: offset where nnode was written
*
* This function is used by LPT garbage collection. LPT garbage collection is
* used only for the "big" LPT model (c->big_lpt == 1). Garbage collection
* simply involves marking all the nodes in the LEB being garbage-collected as
* dirty. The dirty nodes are written next commit, after which the LEB is free
* to be reused.
*
* This function returns %0 on success and a negative error code on failure.
*/
static int make_nnode_dirty(struct ubifs_info *c, int node_num, int lnum,
int offs)
{
struct ubifs_nnode *nnode;
nnode = nnode_lookup(c, node_num);
if (IS_ERR(nnode))
return PTR_ERR(nnode);
if (nnode->parent) {
struct ubifs_nbranch *branch;
branch = &nnode->parent->nbranch[nnode->iip];
if (branch->lnum != lnum || branch->offs != offs)
return 0; /* nnode is obsolete */
} else if (c->lpt_lnum != lnum || c->lpt_offs != offs)
return 0; /* nnode is obsolete */
/* Assumes cnext list is empty i.e. not called during commit */
if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
c->dirty_nn_cnt += 1;
ubifs_add_nnode_dirt(c, nnode);
/* Mark parent and ancestors dirty too */
nnode = nnode->parent;
while (nnode) {
if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
c->dirty_nn_cnt += 1;
ubifs_add_nnode_dirt(c, nnode);
nnode = nnode->parent;
} else
break;
}
}
return 0;
}
/**
* make_pnode_dirty - find a pnode and, if found, make it dirty.
* @c: UBIFS file-system description object
* @node_num: pnode number of pnode to make dirty
* @lnum: LEB number where pnode was written
* @offs: offset where pnode was written
*
* This function is used by LPT garbage collection. LPT garbage collection is
* used only for the "big" LPT model (c->big_lpt == 1). Garbage collection
* simply involves marking all the nodes in the LEB being garbage-collected as
* dirty. The dirty nodes are written next commit, after which the LEB is free
* to be reused.
*
* This function returns %0 on success and a negative error code on failure.
*/
static int make_pnode_dirty(struct ubifs_info *c, int node_num, int lnum,
int offs)
{
struct ubifs_pnode *pnode;
struct ubifs_nbranch *branch;
pnode = pnode_lookup(c, node_num);
if (IS_ERR(pnode))
return PTR_ERR(pnode);
branch = &pnode->parent->nbranch[pnode->iip];
if (branch->lnum != lnum || branch->offs != offs)
return 0;
do_make_pnode_dirty(c, pnode);
return 0;
}
/**
* make_ltab_dirty - make ltab node dirty.
* @c: UBIFS file-system description object
* @lnum: LEB number where ltab was written
* @offs: offset where ltab was written
*
* This function is used by LPT garbage collection. LPT garbage collection is
* used only for the "big" LPT model (c->big_lpt == 1). Garbage collection
* simply involves marking all the nodes in the LEB being garbage-collected as
* dirty. The dirty nodes are written next commit, after which the LEB is free
* to be reused.
*
* This function returns %0 on success and a negative error code on failure.
*/
static int make_ltab_dirty(struct ubifs_info *c, int lnum, int offs)
{
if (lnum != c->ltab_lnum || offs != c->ltab_offs)
return 0; /* This ltab node is obsolete */
if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
c->lpt_drty_flgs |= LTAB_DIRTY;
ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
}
return 0;
}
/**
* make_lsave_dirty - make lsave node dirty.
* @c: UBIFS file-system description object
* @lnum: LEB number where lsave was written
* @offs: offset where lsave was written
*
* This function is used by LPT garbage collection. LPT garbage collection is
* used only for the "big" LPT model (c->big_lpt == 1). Garbage collection
* simply involves marking all the nodes in the LEB being garbage-collected as
* dirty. The dirty nodes are written next commit, after which the LEB is free
* to be reused.
*
* This function returns %0 on success and a negative error code on failure.
*/
static int make_lsave_dirty(struct ubifs_info *c, int lnum, int offs)
{
if (lnum != c->lsave_lnum || offs != c->lsave_offs)
return 0; /* This lsave node is obsolete */
if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) {
c->lpt_drty_flgs |= LSAVE_DIRTY;
ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz);
}
return 0;
}
/**
* make_node_dirty - make node dirty.
* @c: UBIFS file-system description object
* @node_type: LPT node type
* @node_num: node number
* @lnum: LEB number where node was written
* @offs: offset where node was written
*
* This function is used by LPT garbage collection. LPT garbage collection is
* used only for the "big" LPT model (c->big_lpt == 1). Garbage collection
* simply involves marking all the nodes in the LEB being garbage-collected as
* dirty. The dirty nodes are written next commit, after which the LEB is free
* to be reused.
*
* This function returns %0 on success and a negative error code on failure.
*/
static int make_node_dirty(struct ubifs_info *c, int node_type, int node_num,
int lnum, int offs)
{
switch (node_type) {
case UBIFS_LPT_NNODE:
return make_nnode_dirty(c, node_num, lnum, offs);
case UBIFS_LPT_PNODE:
return make_pnode_dirty(c, node_num, lnum, offs);
case UBIFS_LPT_LTAB:
return make_ltab_dirty(c, lnum, offs);
case UBIFS_LPT_LSAVE:
return make_lsave_dirty(c, lnum, offs);
}
return -EINVAL;
}
/**
* get_lpt_node_len - return the length of a node based on its type.
* @c: UBIFS file-system description object
* @node_type: LPT node type
*/
static int get_lpt_node_len(const struct ubifs_info *c, int node_type)
{
switch (node_type) {
case UBIFS_LPT_NNODE:
return c->nnode_sz;
case UBIFS_LPT_PNODE:
return c->pnode_sz;
case UBIFS_LPT_LTAB:
return c->ltab_sz;
case UBIFS_LPT_LSAVE:
return c->lsave_sz;
}
return 0;
}
/**
* get_pad_len - return the length of padding in a buffer.
* @c: UBIFS file-system description object
* @buf: buffer
* @len: length of buffer
*/
static int get_pad_len(const struct ubifs_info *c, uint8_t *buf, int len)
{
int offs, pad_len;
if (c->min_io_size == 1)
return 0;
offs = c->leb_size - len;
pad_len = ALIGN(offs, c->min_io_size) - offs;
return pad_len;
}
/**
* get_lpt_node_type - return type (and node number) of a node in a buffer.
* @c: UBIFS file-system description object
* @buf: buffer
* @node_num: node number is returned here
*/
static int get_lpt_node_type(const struct ubifs_info *c, uint8_t *buf,
int *node_num)
{
uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
int pos = 0, node_type;
node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
*node_num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
return node_type;
}
/**
* is_a_node - determine if a buffer contains a node.
* @c: UBIFS file-system description object
* @buf: buffer
* @len: length of buffer
*
* This function returns %1 if the buffer contains a node or %0 if it does not.
*/
static int is_a_node(const struct ubifs_info *c, uint8_t *buf, int len)
{
uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
int pos = 0, node_type, node_len;
uint16_t crc, calc_crc;
UBIFS: check buffer length when scanning for LPT nodes 'is_a_node()' function was reading from a buffer before checking the buffer length, resulting in an OOPS as follows: BUG: unable to handle kernel paging request at f8f74002 IP: [<f8f9783f>] :ubifs:ubifs_unpack_bits+0xca/0x233 *pde = 19e95067 *pte = 00000000 Oops: 0000 [#1] PREEMPT SMP Modules linked in: ubifs ubi mtdchar bio2mtd mtd brd video output [last unloaded: mtd] Pid: 6414, comm: integck Not tainted (2.6.27-rc6ubifs34 #23) EIP: 0060:[<f8f9783f>] EFLAGS: 00010246 CPU: 0 EIP is at ubifs_unpack_bits+0xca/0x233 [ubifs] EAX: 00000000 EBX: f6090630 ECX: d9badcfc EDX: 00000000 ESI: 00000004 EDI: f8f74002 EBP: d9badcec ESP: d9badcc0 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 Process integck (pid: 6414, ti=d9bac000 task=f727dae0 task.ti=d9bac000) Stack: 00000006 f7306240 00000002 00000000 d9badcfc d9badd00 0000001c 00000000 f6090630 f6090630 f8f74000 d9badd10 f8fa1cc9 00000000 f8f74002 00000000 f8f74002 f60fe128 f6090630 f8f74000 d9badd68 f8fa1e46 00000000 0001e000 Call Trace: [<f8fa1cc9>] ? is_a_node+0x30/0x90 [ubifs] [<f8fa1e46>] ? dbg_check_ltab+0x11d/0x5bd [ubifs] [<f8fa388f>] ? ubifs_lpt_start_commit+0x42/0xed3 [ubifs] [<c038e76a>] ? mutex_unlock+0x8/0xa [<f8f9625d>] ? ubifs_tnc_start_commit+0x1c8/0xedb [ubifs] [<f8f8d90b>] ? do_commit+0x187/0x523 [ubifs] [<c038e76a>] ? mutex_unlock+0x8/0xa [<f8f7ca17>] ? bud_wbuf_callback+0x22/0x28 [ubifs] [<f8f8dd1d>] ? ubifs_run_commit+0x76/0xc0 [ubifs] [<f8f8032c>] ? ubifs_sync_fs+0xd2/0xe6 [ubifs] [<c01a2e97>] ? vfs_quota_sync+0x0/0x17e [<c01a5ba6>] ? quota_sync_sb+0x26/0xbb [<c01a2e97>] ? vfs_quota_sync+0x0/0x17e [<c01a5c5d>] ? sync_dquots+0x22/0x12c [<c0173d1b>] ? __fsync_super+0x19/0x68 [<c0173d75>] ? fsync_super+0xb/0x19 [<c0174065>] ? generic_shutdown_super+0x22/0xe7 [<c01a31fc>] ? vfs_quota_off+0x0/0x5fd [<f8f7cf4d>] ? ubifs_kill_sb+0x31/0x35 [ubifs] [<c01741f9>] ? deactivate_super+0x5e/0x71 [<c0187610>] ? mntput_no_expire+0x82/0xe4 [<c0187905>] ? sys_umount+0x4c/0x2f6 [<c0187bc8>] ? sys_oldumount+0x19/0x1b [<c0103b71>] ? sysenter_do_call+0x12/0x25 ======================= Code: c1 f8 03 8d 04 07 8b 4d e8 89 01 8b 45 e4 89 10 89 d8 89 f1 d3 e8 85 c0 74 07 29 d6 83 fe 20 75 2a 89 d8 83 c4 20 5b 5e 5f 5d EIP: [<f8f9783f>] ubifs_unpack_bits+0xca/0x233 [ubifs] SS:ESP 0068:d9badcc0 ---[ end trace 1f02572436518c13 ]--- Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-09-26 17:52:21 +08:00
if (len < UBIFS_LPT_CRC_BYTES + (UBIFS_LPT_TYPE_BITS + 7) / 8)
return 0;
node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
if (node_type == UBIFS_LPT_NOT_A_NODE)
return 0;
node_len = get_lpt_node_len(c, node_type);
if (!node_len || node_len > len)
return 0;
pos = 0;
addr = buf;
crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
node_len - UBIFS_LPT_CRC_BYTES);
if (crc != calc_crc)
return 0;
return 1;
}
/**
* lpt_gc_lnum - garbage collect a LPT LEB.
* @c: UBIFS file-system description object
* @lnum: LEB number to garbage collect
*
* LPT garbage collection is used only for the "big" LPT model
* (c->big_lpt == 1). Garbage collection simply involves marking all the nodes
* in the LEB being garbage-collected as dirty. The dirty nodes are written
* next commit, after which the LEB is free to be reused.
*
* This function returns %0 on success and a negative error code on failure.
*/
static int lpt_gc_lnum(struct ubifs_info *c, int lnum)
{
int err, len = c->leb_size, node_type, node_num, node_len, offs;
void *buf = c->lpt_buf;
dbg_lp("LEB %d", lnum);
err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
if (err) {
ubifs_err("cannot read LEB %d, error %d", lnum, err);
return err;
}
while (1) {
if (!is_a_node(c, buf, len)) {
int pad_len;
pad_len = get_pad_len(c, buf, len);
if (pad_len) {
buf += pad_len;
len -= pad_len;
continue;
}
return 0;
}
node_type = get_lpt_node_type(c, buf, &node_num);
node_len = get_lpt_node_len(c, node_type);
offs = c->leb_size - len;
ubifs_assert(node_len != 0);
mutex_lock(&c->lp_mutex);
err = make_node_dirty(c, node_type, node_num, lnum, offs);
mutex_unlock(&c->lp_mutex);
if (err)
return err;
buf += node_len;
len -= node_len;
}
return 0;
}
/**
* lpt_gc - LPT garbage collection.
* @c: UBIFS file-system description object
*
* Select a LPT LEB for LPT garbage collection and call 'lpt_gc_lnum()'.
* Returns %0 on success and a negative error code on failure.
*/
static int lpt_gc(struct ubifs_info *c)
{
int i, lnum = -1, dirty = 0;
mutex_lock(&c->lp_mutex);
for (i = 0; i < c->lpt_lebs; i++) {
ubifs_assert(!c->ltab[i].tgc);
if (i + c->lpt_first == c->nhead_lnum ||
c->ltab[i].free + c->ltab[i].dirty == c->leb_size)
continue;
if (c->ltab[i].dirty > dirty) {
dirty = c->ltab[i].dirty;
lnum = i + c->lpt_first;
}
}
mutex_unlock(&c->lp_mutex);
if (lnum == -1)
return -ENOSPC;
return lpt_gc_lnum(c, lnum);
}
/**
* ubifs_lpt_start_commit - UBIFS commit starts.
* @c: the UBIFS file-system description object
*
* This function has to be called when UBIFS starts the commit operation.
* This function "freezes" all currently dirty LEB properties and does not
* change them anymore. Further changes are saved and tracked separately
* because they are not part of this commit. This function returns zero in case
* of success and a negative error code in case of failure.
*/
int ubifs_lpt_start_commit(struct ubifs_info *c)
{
int err, cnt;
dbg_lp("");
mutex_lock(&c->lp_mutex);
err = dbg_chk_lpt_free_spc(c);
if (err)
goto out;
err = dbg_check_ltab(c);
if (err)
goto out;
if (c->check_lpt_free) {
/*
* We ensure there is enough free space in
* ubifs_lpt_post_commit() by marking nodes dirty. That
* information is lost when we unmount, so we also need
* to check free space once after mounting also.
*/
c->check_lpt_free = 0;
while (need_write_all(c)) {
mutex_unlock(&c->lp_mutex);
err = lpt_gc(c);
if (err)
return err;
mutex_lock(&c->lp_mutex);
}
}
lpt_tgc_start(c);
if (!c->dirty_pn_cnt) {
dbg_cmt("no cnodes to commit");
err = 0;
goto out;
}
if (!c->big_lpt && need_write_all(c)) {
/* If needed, write everything */
err = make_tree_dirty(c);
if (err)
goto out;
lpt_tgc_start(c);
}
if (c->big_lpt)
populate_lsave(c);
cnt = get_cnodes_to_commit(c);
ubifs_assert(cnt != 0);
err = layout_cnodes(c);
if (err)
goto out;
/* Copy the LPT's own lprops for end commit to write */
memcpy(c->ltab_cmt, c->ltab,
sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
c->lpt_drty_flgs &= ~(LTAB_DIRTY | LSAVE_DIRTY);
out:
mutex_unlock(&c->lp_mutex);
return err;
}
/**
* free_obsolete_cnodes - free obsolete cnodes for commit end.
* @c: UBIFS file-system description object
*/
static void free_obsolete_cnodes(struct ubifs_info *c)
{
struct ubifs_cnode *cnode, *cnext;
cnext = c->lpt_cnext;
if (!cnext)
return;
do {
cnode = cnext;
cnext = cnode->cnext;
if (test_bit(OBSOLETE_CNODE, &cnode->flags))
kfree(cnode);
else
cnode->cnext = NULL;
} while (cnext != c->lpt_cnext);
c->lpt_cnext = NULL;
}
/**
* ubifs_lpt_end_commit - finish the commit operation.
* @c: the UBIFS file-system description object
*
* This function has to be called when the commit operation finishes. It
* flushes the changes which were "frozen" by 'ubifs_lprops_start_commit()' to
* the media. Returns zero in case of success and a negative error code in case
* of failure.
*/
int ubifs_lpt_end_commit(struct ubifs_info *c)
{
int err;
dbg_lp("");
if (!c->lpt_cnext)
return 0;
err = write_cnodes(c);
if (err)
return err;
mutex_lock(&c->lp_mutex);
free_obsolete_cnodes(c);
mutex_unlock(&c->lp_mutex);
return 0;
}
/**
* ubifs_lpt_post_commit - post commit LPT trivial GC and LPT GC.
* @c: UBIFS file-system description object
*
* LPT trivial GC is completed after a commit. Also LPT GC is done after a
* commit for the "big" LPT model.
*/
int ubifs_lpt_post_commit(struct ubifs_info *c)
{
int err;
mutex_lock(&c->lp_mutex);
err = lpt_tgc_end(c);
if (err)
goto out;
if (c->big_lpt)
while (need_write_all(c)) {
mutex_unlock(&c->lp_mutex);
err = lpt_gc(c);
if (err)
return err;
mutex_lock(&c->lp_mutex);
}
out:
mutex_unlock(&c->lp_mutex);
return err;
}
/**
* first_nnode - find the first nnode in memory.
* @c: UBIFS file-system description object
* @hght: height of tree where nnode found is returned here
*
* This function returns a pointer to the nnode found or %NULL if no nnode is
* found. This function is a helper to 'ubifs_lpt_free()'.
*/
static struct ubifs_nnode *first_nnode(struct ubifs_info *c, int *hght)
{
struct ubifs_nnode *nnode;
int h, i, found;
nnode = c->nroot;
*hght = 0;
if (!nnode)
return NULL;
for (h = 1; h < c->lpt_hght; h++) {
found = 0;
for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
if (nnode->nbranch[i].nnode) {
found = 1;
nnode = nnode->nbranch[i].nnode;
*hght = h;
break;
}
}
if (!found)
break;
}
return nnode;
}
/**
* next_nnode - find the next nnode in memory.
* @c: UBIFS file-system description object
* @nnode: nnode from which to start.
* @hght: height of tree where nnode is, is passed and returned here
*
* This function returns a pointer to the nnode found or %NULL if no nnode is
* found. This function is a helper to 'ubifs_lpt_free()'.
*/
static struct ubifs_nnode *next_nnode(struct ubifs_info *c,
struct ubifs_nnode *nnode, int *hght)
{
struct ubifs_nnode *parent;
int iip, h, i, found;
parent = nnode->parent;
if (!parent)
return NULL;
if (nnode->iip == UBIFS_LPT_FANOUT - 1) {
*hght -= 1;
return parent;
}
for (iip = nnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) {
nnode = parent->nbranch[iip].nnode;
if (nnode)
break;
}
if (!nnode) {
*hght -= 1;
return parent;
}
for (h = *hght + 1; h < c->lpt_hght; h++) {
found = 0;
for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
if (nnode->nbranch[i].nnode) {
found = 1;
nnode = nnode->nbranch[i].nnode;
*hght = h;
break;
}
}
if (!found)
break;
}
return nnode;
}
/**
* ubifs_lpt_free - free resources owned by the LPT.
* @c: UBIFS file-system description object
* @wr_only: free only resources used for writing
*/
void ubifs_lpt_free(struct ubifs_info *c, int wr_only)
{
struct ubifs_nnode *nnode;
int i, hght;
/* Free write-only things first */
free_obsolete_cnodes(c); /* Leftover from a failed commit */
vfree(c->ltab_cmt);
c->ltab_cmt = NULL;
vfree(c->lpt_buf);
c->lpt_buf = NULL;
kfree(c->lsave);
c->lsave = NULL;
if (wr_only)
return;
/* Now free the rest */
nnode = first_nnode(c, &hght);
while (nnode) {
for (i = 0; i < UBIFS_LPT_FANOUT; i++)
kfree(nnode->nbranch[i].nnode);
nnode = next_nnode(c, nnode, &hght);
}
for (i = 0; i < LPROPS_HEAP_CNT; i++)
kfree(c->lpt_heap[i].arr);
kfree(c->dirty_idx.arr);
kfree(c->nroot);
vfree(c->ltab);
kfree(c->lpt_nod_buf);
}
#ifdef CONFIG_UBIFS_FS_DEBUG
/**
* dbg_is_all_ff - determine if a buffer contains only 0xFF bytes.
* @buf: buffer
* @len: buffer length
*/
static int dbg_is_all_ff(uint8_t *buf, int len)
{
int i;
for (i = 0; i < len; i++)
if (buf[i] != 0xff)
return 0;
return 1;
}
/**
* dbg_is_nnode_dirty - determine if a nnode is dirty.
* @c: the UBIFS file-system description object
* @lnum: LEB number where nnode was written
* @offs: offset where nnode was written
*/
static int dbg_is_nnode_dirty(struct ubifs_info *c, int lnum, int offs)
{
struct ubifs_nnode *nnode;
int hght;
/* Entire tree is in memory so first_nnode / next_nnode are OK */
nnode = first_nnode(c, &hght);
for (; nnode; nnode = next_nnode(c, nnode, &hght)) {
struct ubifs_nbranch *branch;
cond_resched();
if (nnode->parent) {
branch = &nnode->parent->nbranch[nnode->iip];
if (branch->lnum != lnum || branch->offs != offs)
continue;
if (test_bit(DIRTY_CNODE, &nnode->flags))
return 1;
return 0;
} else {
if (c->lpt_lnum != lnum || c->lpt_offs != offs)
continue;
if (test_bit(DIRTY_CNODE, &nnode->flags))
return 1;
return 0;
}
}
return 1;
}
/**
* dbg_is_pnode_dirty - determine if a pnode is dirty.
* @c: the UBIFS file-system description object
* @lnum: LEB number where pnode was written
* @offs: offset where pnode was written
*/
static int dbg_is_pnode_dirty(struct ubifs_info *c, int lnum, int offs)
{
int i, cnt;
cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
for (i = 0; i < cnt; i++) {
struct ubifs_pnode *pnode;
struct ubifs_nbranch *branch;
cond_resched();
pnode = pnode_lookup(c, i);
if (IS_ERR(pnode))
return PTR_ERR(pnode);
branch = &pnode->parent->nbranch[pnode->iip];
if (branch->lnum != lnum || branch->offs != offs)
continue;
if (test_bit(DIRTY_CNODE, &pnode->flags))
return 1;
return 0;
}
return 1;
}
/**
* dbg_is_ltab_dirty - determine if a ltab node is dirty.
* @c: the UBIFS file-system description object
* @lnum: LEB number where ltab node was written
* @offs: offset where ltab node was written
*/
static int dbg_is_ltab_dirty(struct ubifs_info *c, int lnum, int offs)
{
if (lnum != c->ltab_lnum || offs != c->ltab_offs)
return 1;
return (c->lpt_drty_flgs & LTAB_DIRTY) != 0;
}
/**
* dbg_is_lsave_dirty - determine if a lsave node is dirty.
* @c: the UBIFS file-system description object
* @lnum: LEB number where lsave node was written
* @offs: offset where lsave node was written
*/
static int dbg_is_lsave_dirty(struct ubifs_info *c, int lnum, int offs)
{
if (lnum != c->lsave_lnum || offs != c->lsave_offs)
return 1;
return (c->lpt_drty_flgs & LSAVE_DIRTY) != 0;
}
/**
* dbg_is_node_dirty - determine if a node is dirty.
* @c: the UBIFS file-system description object
* @node_type: node type
* @lnum: LEB number where node was written
* @offs: offset where node was written
*/
static int dbg_is_node_dirty(struct ubifs_info *c, int node_type, int lnum,
int offs)
{
switch (node_type) {
case UBIFS_LPT_NNODE:
return dbg_is_nnode_dirty(c, lnum, offs);
case UBIFS_LPT_PNODE:
return dbg_is_pnode_dirty(c, lnum, offs);
case UBIFS_LPT_LTAB:
return dbg_is_ltab_dirty(c, lnum, offs);
case UBIFS_LPT_LSAVE:
return dbg_is_lsave_dirty(c, lnum, offs);
}
return 1;
}
/**
* dbg_check_ltab_lnum - check the ltab for a LPT LEB number.
* @c: the UBIFS file-system description object
* @lnum: LEB number where node was written
* @offs: offset where node was written
*
* This function returns %0 on success and a negative error code on failure.
*/
static int dbg_check_ltab_lnum(struct ubifs_info *c, int lnum)
{
int err, len = c->leb_size, dirty = 0, node_type, node_num, node_len;
int ret;
void *buf, *p;
if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
return 0;
buf = p = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
if (!buf) {
ubifs_err("cannot allocate memory for ltab checking");
return 0;
}
dbg_lp("LEB %d", lnum);
err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
if (err) {
dbg_msg("ubi_read failed, LEB %d, error %d", lnum, err);
goto out;
}
while (1) {
if (!is_a_node(c, p, len)) {
int i, pad_len;
pad_len = get_pad_len(c, p, len);
if (pad_len) {
p += pad_len;
len -= pad_len;
dirty += pad_len;
continue;
}
if (!dbg_is_all_ff(p, len)) {
dbg_msg("invalid empty space in LEB %d at %d",
lnum, c->leb_size - len);
err = -EINVAL;
}
i = lnum - c->lpt_first;
if (len != c->ltab[i].free) {
dbg_msg("invalid free space in LEB %d "
"(free %d, expected %d)",
lnum, len, c->ltab[i].free);
err = -EINVAL;
}
if (dirty != c->ltab[i].dirty) {
dbg_msg("invalid dirty space in LEB %d "
"(dirty %d, expected %d)",
lnum, dirty, c->ltab[i].dirty);
err = -EINVAL;
}
goto out;
}
node_type = get_lpt_node_type(c, p, &node_num);
node_len = get_lpt_node_len(c, node_type);
ret = dbg_is_node_dirty(c, node_type, lnum, c->leb_size - len);
if (ret == 1)
dirty += node_len;
p += node_len;
len -= node_len;
}
err = 0;
out:
vfree(buf);
return err;
}
/**
* dbg_check_ltab - check the free and dirty space in the ltab.
* @c: the UBIFS file-system description object
*
* This function returns %0 on success and a negative error code on failure.
*/
int dbg_check_ltab(struct ubifs_info *c)
{
int lnum, err, i, cnt;
if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
return 0;
/* Bring the entire tree into memory */
cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
for (i = 0; i < cnt; i++) {
struct ubifs_pnode *pnode;
pnode = pnode_lookup(c, i);
if (IS_ERR(pnode))
return PTR_ERR(pnode);
cond_resched();
}
/* Check nodes */
err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)c->nroot, 0, 0);
if (err)
return err;
/* Check each LEB */
for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) {
err = dbg_check_ltab_lnum(c, lnum);
if (err) {
dbg_err("failed at LEB %d", lnum);
return err;
}
}
dbg_lp("succeeded");
return 0;
}
/**
* dbg_chk_lpt_free_spc - check LPT free space is enough to write entire LPT.
* @c: the UBIFS file-system description object
*
* This function returns %0 on success and a negative error code on failure.
*/
int dbg_chk_lpt_free_spc(struct ubifs_info *c)
{
long long free = 0;
int i;
if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
return 0;
for (i = 0; i < c->lpt_lebs; i++) {
if (c->ltab[i].tgc || c->ltab[i].cmt)
continue;
if (i + c->lpt_first == c->nhead_lnum)
free += c->leb_size - c->nhead_offs;
else if (c->ltab[i].free == c->leb_size)
free += c->leb_size;
}
if (free < c->lpt_sz) {
dbg_err("LPT space error: free %lld lpt_sz %lld",
free, c->lpt_sz);
dbg_dump_lpt_info(c);
dbg_dump_lpt_lebs(c);
dump_stack();
return -EINVAL;
}
return 0;
}
/**
* dbg_chk_lpt_sz - check LPT does not write more than LPT size.
* @c: the UBIFS file-system description object
* @action: what to do
* @len: length written
*
* This function returns %0 on success and a negative error code on failure.
* The @action argument may be one of:
* o %0 - LPT debugging checking starts, initialize debugging variables;
* o %1 - wrote an LPT node, increase LPT size by @len bytes;
* o %2 - switched to a different LEB and wasted @len bytes;
* o %3 - check that we've written the right number of bytes.
* o %4 - wasted @len bytes;
*/
int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
{
struct ubifs_debug_info *d = c->dbg;
long long chk_lpt_sz, lpt_sz;
int err = 0;
if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
return 0;
switch (action) {
case 0:
d->chk_lpt_sz = 0;
d->chk_lpt_sz2 = 0;
d->chk_lpt_lebs = 0;
d->chk_lpt_wastage = 0;
if (c->dirty_pn_cnt > c->pnode_cnt) {
dbg_err("dirty pnodes %d exceed max %d",
c->dirty_pn_cnt, c->pnode_cnt);
err = -EINVAL;
}
if (c->dirty_nn_cnt > c->nnode_cnt) {
dbg_err("dirty nnodes %d exceed max %d",
c->dirty_nn_cnt, c->nnode_cnt);
err = -EINVAL;
}
return err;
case 1:
d->chk_lpt_sz += len;
return 0;
case 2:
d->chk_lpt_sz += len;
d->chk_lpt_wastage += len;
d->chk_lpt_lebs += 1;
return 0;
case 3:
chk_lpt_sz = c->leb_size;
chk_lpt_sz *= d->chk_lpt_lebs;
chk_lpt_sz += len - c->nhead_offs;
if (d->chk_lpt_sz != chk_lpt_sz) {
dbg_err("LPT wrote %lld but space used was %lld",
d->chk_lpt_sz, chk_lpt_sz);
err = -EINVAL;
}
if (d->chk_lpt_sz > c->lpt_sz) {
dbg_err("LPT wrote %lld but lpt_sz is %lld",
d->chk_lpt_sz, c->lpt_sz);
err = -EINVAL;
}
if (d->chk_lpt_sz2 && d->chk_lpt_sz != d->chk_lpt_sz2) {
dbg_err("LPT layout size %lld but wrote %lld",
d->chk_lpt_sz, d->chk_lpt_sz2);
err = -EINVAL;
}
if (d->chk_lpt_sz2 && d->new_nhead_offs != len) {
dbg_err("LPT new nhead offs: expected %d was %d",
d->new_nhead_offs, len);
err = -EINVAL;
}
lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
lpt_sz += c->ltab_sz;
if (c->big_lpt)
lpt_sz += c->lsave_sz;
if (d->chk_lpt_sz - d->chk_lpt_wastage > lpt_sz) {
dbg_err("LPT chk_lpt_sz %lld + waste %lld exceeds %lld",
d->chk_lpt_sz, d->chk_lpt_wastage, lpt_sz);
err = -EINVAL;
}
if (err) {
dbg_dump_lpt_info(c);
dbg_dump_lpt_lebs(c);
dump_stack();
}
d->chk_lpt_sz2 = d->chk_lpt_sz;
d->chk_lpt_sz = 0;
d->chk_lpt_wastage = 0;
d->chk_lpt_lebs = 0;
d->new_nhead_offs = len;
return err;
case 4:
d->chk_lpt_sz += len;
d->chk_lpt_wastage += len;
return 0;
default:
return -EINVAL;
}
}
/**
* dbg_dump_lpt_leb - dump an LPT LEB.
* @c: UBIFS file-system description object
* @lnum: LEB number to dump
*
* This function dumps an LEB from LPT area. Nodes in this area are very
* different to nodes in the main area (e.g., they do not have common headers,
* they do not have 8-byte alignments, etc), so we have a separate function to
* dump LPT area LEBs. Note, LPT has to be locked by the caller.
*/
static void dump_lpt_leb(const struct ubifs_info *c, int lnum)
{
int err, len = c->leb_size, node_type, node_num, node_len, offs;
void *buf, *p;
printk(KERN_DEBUG "(pid %d) start dumping LEB %d\n",
current->pid, lnum);
buf = p = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
if (!buf) {
ubifs_err("cannot allocate memory to dump LPT");
return;
}
err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
if (err) {
ubifs_err("cannot read LEB %d, error %d", lnum, err);
goto out;
}
while (1) {
offs = c->leb_size - len;
if (!is_a_node(c, p, len)) {
int pad_len;
pad_len = get_pad_len(c, p, len);
if (pad_len) {
printk(KERN_DEBUG "LEB %d:%d, pad %d bytes\n",
lnum, offs, pad_len);
p += pad_len;
len -= pad_len;
continue;
}
if (len)
printk(KERN_DEBUG "LEB %d:%d, free %d bytes\n",
lnum, offs, len);
break;
}
node_type = get_lpt_node_type(c, p, &node_num);
switch (node_type) {
case UBIFS_LPT_PNODE:
{
node_len = c->pnode_sz;
if (c->big_lpt)
printk(KERN_DEBUG "LEB %d:%d, pnode num %d\n",
lnum, offs, node_num);
else
printk(KERN_DEBUG "LEB %d:%d, pnode\n",
lnum, offs);
break;
}
case UBIFS_LPT_NNODE:
{
int i;
struct ubifs_nnode nnode;
node_len = c->nnode_sz;
if (c->big_lpt)
printk(KERN_DEBUG "LEB %d:%d, nnode num %d, ",
lnum, offs, node_num);
else
printk(KERN_DEBUG "LEB %d:%d, nnode, ",
lnum, offs);
err = ubifs_unpack_nnode(c, p, &nnode);
for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
printk(KERN_CONT "%d:%d", nnode.nbranch[i].lnum,
nnode.nbranch[i].offs);
if (i != UBIFS_LPT_FANOUT - 1)
printk(KERN_CONT ", ");
}
printk(KERN_CONT "\n");
break;
}
case UBIFS_LPT_LTAB:
node_len = c->ltab_sz;
printk(KERN_DEBUG "LEB %d:%d, ltab\n",
lnum, offs);
break;
case UBIFS_LPT_LSAVE:
node_len = c->lsave_sz;
printk(KERN_DEBUG "LEB %d:%d, lsave len\n", lnum, offs);
break;
default:
ubifs_err("LPT node type %d not recognized", node_type);
goto out;
}
p += node_len;
len -= node_len;
}
printk(KERN_DEBUG "(pid %d) finish dumping LEB %d\n",
current->pid, lnum);
out:
vfree(buf);
return;
}
/**
* dbg_dump_lpt_lebs - dump LPT lebs.
* @c: UBIFS file-system description object
*
* This function dumps all LPT LEBs. The caller has to make sure the LPT is
* locked.
*/
void dbg_dump_lpt_lebs(const struct ubifs_info *c)
{
int i;
printk(KERN_DEBUG "(pid %d) start dumping all LPT LEBs\n",
current->pid);
for (i = 0; i < c->lpt_lebs; i++)
dump_lpt_leb(c, i + c->lpt_first);
printk(KERN_DEBUG "(pid %d) finish dumping all LPT LEBs\n",
current->pid);
}
/**
* dbg_populate_lsave - debugging version of 'populate_lsave()'
* @c: UBIFS file-system description object
*
* This is a debugging version for 'populate_lsave()' which populates lsave
* with random LEBs instead of useful LEBs, which is good for test coverage.
* Returns zero if lsave has not been populated (this debugging feature is
* disabled) an non-zero if lsave has been populated.
*/
static int dbg_populate_lsave(struct ubifs_info *c)
{
struct ubifs_lprops *lprops;
struct ubifs_lpt_heap *heap;
int i;
if (!(ubifs_chk_flags & UBIFS_CHK_GEN))
return 0;
if (random32() & 3)
return 0;
for (i = 0; i < c->lsave_cnt; i++)
c->lsave[i] = c->main_first;
list_for_each_entry(lprops, &c->empty_list, list)
c->lsave[random32() % c->lsave_cnt] = lprops->lnum;
list_for_each_entry(lprops, &c->freeable_list, list)
c->lsave[random32() % c->lsave_cnt] = lprops->lnum;
list_for_each_entry(lprops, &c->frdi_idx_list, list)
c->lsave[random32() % c->lsave_cnt] = lprops->lnum;
heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
for (i = 0; i < heap->cnt; i++)
c->lsave[random32() % c->lsave_cnt] = heap->arr[i]->lnum;
heap = &c->lpt_heap[LPROPS_DIRTY - 1];
for (i = 0; i < heap->cnt; i++)
c->lsave[random32() % c->lsave_cnt] = heap->arr[i]->lnum;
heap = &c->lpt_heap[LPROPS_FREE - 1];
for (i = 0; i < heap->cnt; i++)
c->lsave[random32() % c->lsave_cnt] = heap->arr[i]->lnum;
return 1;
}
#endif /* CONFIG_UBIFS_FS_DEBUG */