Revision ebff65473f56e6c30de928fd6a4f1ce5ae36e8c5 authored by Shawn Guo on 02 December 2013, 05:26:50 UTC, committed by Mark Brown on 02 December 2013, 11:50:53 UTC
Since devm_card_release() expects parameter 'res' to be a pointer to struct snd_soc_card, devm_snd_soc_register_card() should really pass such a pointer rather than the one to struct device. This bug causes the kernel Oops below with imx-sgtl500 driver when we remove the module. It happens because with 'card' pointing to the wrong structure, card->num_rtd becomes 0 in function soc_remove_dai_links(). Consequently, soc_remove_link_components() and in turn soc_cleanup_codec[platform]_debugfs() will not be called on card removal. It results in that debugfs_card_root is being removed while its child entries debugfs_codec_root and debugfs_platform_root are still there, and thus the kernel Oops. Fix the bug by correcting the parameter 'res' to be the pointer to struct snd_soc_card. $ lsmod Module Size Used by snd_soc_imx_sgtl5000 3506 0 snd_soc_sgtl5000 13677 2 snd_soc_imx_audmux 5324 1 snd_soc_imx_sgtl5000 snd_soc_fsl_ssi 8139 2 imx_pcm_dma 1380 1 snd_soc_fsl_ssi $ rmmod snd_soc_imx_sgtl5000 Unable to handle kernel paging request at virtual address e594025c pgd = be134000 [e594025c] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: snd_soc_imx_sgtl5000(-) snd_soc_sgtl5000 snd_soc_imx_audmux snd_soc_fsl_ssi imx_pcm_dma CPU: 0 PID: 1793 Comm: rmmod Not tainted 3.13.0-rc1 #1570 task: bee28900 ti: bfbec000 task.ti: bfbec000 PC is at debugfs_remove_recursive+0x28/0x154 LR is at snd_soc_unregister_card+0xa0/0xcc pc : [<80252b38>] lr : [<80496ac4>] psr: a0000013 sp : bfbede00 ip : bfbede28 fp : bfbede24 r10: 803281d4 r9 : bfbec000 r8 : 803271ac r7 : bef54440 r6 : 00000004 r5 : bf9a4010 r4 : bf9a4010 r3 : e5940224 r2 : 00000000 r1 : bef54450 r0 : 803271ac Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 10c53c7d Table: 4e13404a DAC: 00000015 Process rmmod (pid: 1793, stack limit = 0xbfbec240) Stack: (0xbfbede00 to 0xbfbee000) de00: 00000000 bf9a4010 bf9a4010 00000004 bef54440 bec89000 bfbede44 bfbede28 de20: 80496ac4 80252b1c 804a4b60 bfbede60 bf9a4010 00000004 bfbede54 bfbede48 de40: 804a4b74 80496a30 bfbede94 bfbede58 80328728 804a4b6c bfbede94 a0000013 de60: bf1b5800 bef54440 00000002 bf9a4010 7f0169f8 bf9a4044 00000081 8000e9c4 de80: bfbec000 00000000 bfbedeac bfbede98 80328cb0 80328618 7f016000 bf9a4010 dea0: bfbedec4 bfbedeb0 8032561c 80328c84 bf9a4010 7f0169f8 bfbedee4 bfbedec8 dec0: 80325e84 803255a8 bee28900 7f0169f8 00000000 78208d30 bfbedefc bfbedee8 dee0: 80325410 80325dd4 beca8100 7f0169f8 bfbedf14 bfbedf00 803264f8 803253c8 df00: 7f01635c 7f016a3c bfbedf24 bfbedf18 80327098 803264d4 bfbedf34 bfbedf28 df20: 7f016370 80327090 bfbedfa4 bfbedf38 80085ef0 7f016368 bfbedf54 5f646e73 df40: 5f636f73 5f786d69 6c746773 30303035 00000000 78208008 bfbedf84 bfbedf68 df60: 800613b0 80061194 fffffffe 78208d00 7efc2f07 00000081 7f016a3c 00000800 df80: bfbedf84 00000000 00000000 fffffffe 78208d00 7efc2f07 00000000 bfbedfa8 dfa0: 8000e800 80085dcc fffffffe 78208d00 78208d30 00000800 a8c82400 a8c82400 dfc0: fffffffe 78208d00 7efc2f07 00000081 00000002 00000000 78208008 00000800 dfe0: 7efc2e1c 7efc2ba8 76f5ca47 76edec7c 80000010 78208d30 00000000 00000000 Backtrace: [<80252b10>] (debugfs_remove_recursive+0x0/0x154) from [<80496ac4>] (snd_soc_unregister_card+0xa0/0xcc) r8:bec89000 r7:bef54440 r6:00000004 r5:bf9a4010 r4:bf9a4010 r3:00000000 [<80496a24>] (snd_soc_unregister_card+0x0/0xcc) from [<804a4b74>] (devm_card_release+0x14/0x18) r6:00000004 r5:bf9a4010 r4:bfbede60 r3:804a4b60 [<804a4b60>] (devm_card_release+0x0/0x18) from [<80328728>] (release_nodes+0x11c/0x1dc) [<8032860c>] (release_nodes+0x0/0x1dc) from [<80328cb0>] (devres_release_all+0x38/0x54) [<80328c78>] (devres_release_all+0x0/0x54) from [<8032561c>] (__device_release_driver+0x80/0xd4) r4:bf9a4010 r3:7f016000 [<8032559c>] (__device_release_driver+0x0/0xd4) from [<80325e84>] (driver_detach+0xbc/0xc0) r5:7f0169f8 r4:bf9a4010 [<80325dc8>] (driver_detach+0x0/0xc0) from [<80325410>] (bus_remove_driver+0x54/0x98) r6:78208d30 r5:00000000 r4:7f0169f8 r3:bee28900 [<803253bc>] (bus_remove_driver+0x0/0x98) from [<803264f8>] (driver_unregister+0x30/0x50) r4:7f0169f8 r3:beca8100 [<803264c8>] (driver_unregister+0x0/0x50) from [<80327098>] (platform_driver_unregister+0x14/0x18) r4:7f016a3c r3:7f01635c [<80327084>] (platform_driver_unregister+0x0/0x18) from [<7f016370>] (imx_sgtl5000_driver_exit+0x14/0x1c [snd_soc_imx_sgtl5000]) [<7f01635c>] (imx_sgtl5000_driver_exit+0x0/0x1c [snd_soc_imx_sgtl5000]) from [<80085ef0>] (SyS_delete_module+0x130/0x18c) [<80085dc0>] (SyS_delete_module+0x0/0x18c) from [<8000e800>] (ret_fast_syscall+0x0/0x48) r6:7efc2f07 r5:78208d00 r4:fffffffe Code: 889da9f8 e5983020 e3530000 089da9f8 (e5933038) ---[ end trace 825e7e125251a225 ]--- Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Mark Brown <broonie@linaro.org>
1 parent 8f1ec93
file.c
/*
* Squashfs - a compressed read only filesystem for Linux
*
* Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
* Phillip Lougher <phillip@squashfs.org.uk>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2,
* or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* file.c
*/
/*
* This file contains code for handling regular files. A regular file
* consists of a sequence of contiguous compressed blocks, and/or a
* compressed fragment block (tail-end packed block). The compressed size
* of each datablock is stored in a block list contained within the
* file inode (itself stored in one or more compressed metadata blocks).
*
* To speed up access to datablocks when reading 'large' files (256 Mbytes or
* larger), the code implements an index cache that caches the mapping from
* block index to datablock location on disk.
*
* The index cache allows Squashfs to handle large files (up to 1.75 TiB) while
* retaining a simple and space-efficient block list on disk. The cache
* is split into slots, caching up to eight 224 GiB files (128 KiB blocks).
* Larger files use multiple slots, with 1.75 TiB files using all 8 slots.
* The index cache is designed to be memory efficient, and by default uses
* 16 KiB.
*/
#include <linux/fs.h>
#include <linux/vfs.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/pagemap.h>
#include <linux/mutex.h>
#include "squashfs_fs.h"
#include "squashfs_fs_sb.h"
#include "squashfs_fs_i.h"
#include "squashfs.h"
/*
* Locate cache slot in range [offset, index] for specified inode. If
* there's more than one return the slot closest to index.
*/
static struct meta_index *locate_meta_index(struct inode *inode, int offset,
int index)
{
struct meta_index *meta = NULL;
struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
int i;
mutex_lock(&msblk->meta_index_mutex);
TRACE("locate_meta_index: index %d, offset %d\n", index, offset);
if (msblk->meta_index == NULL)
goto not_allocated;
for (i = 0; i < SQUASHFS_META_SLOTS; i++) {
if (msblk->meta_index[i].inode_number == inode->i_ino &&
msblk->meta_index[i].offset >= offset &&
msblk->meta_index[i].offset <= index &&
msblk->meta_index[i].locked == 0) {
TRACE("locate_meta_index: entry %d, offset %d\n", i,
msblk->meta_index[i].offset);
meta = &msblk->meta_index[i];
offset = meta->offset;
}
}
if (meta)
meta->locked = 1;
not_allocated:
mutex_unlock(&msblk->meta_index_mutex);
return meta;
}
/*
* Find and initialise an empty cache slot for index offset.
*/
static struct meta_index *empty_meta_index(struct inode *inode, int offset,
int skip)
{
struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
struct meta_index *meta = NULL;
int i;
mutex_lock(&msblk->meta_index_mutex);
TRACE("empty_meta_index: offset %d, skip %d\n", offset, skip);
if (msblk->meta_index == NULL) {
/*
* First time cache index has been used, allocate and
* initialise. The cache index could be allocated at
* mount time but doing it here means it is allocated only
* if a 'large' file is read.
*/
msblk->meta_index = kcalloc(SQUASHFS_META_SLOTS,
sizeof(*(msblk->meta_index)), GFP_KERNEL);
if (msblk->meta_index == NULL) {
ERROR("Failed to allocate meta_index\n");
goto failed;
}
for (i = 0; i < SQUASHFS_META_SLOTS; i++) {
msblk->meta_index[i].inode_number = 0;
msblk->meta_index[i].locked = 0;
}
msblk->next_meta_index = 0;
}
for (i = SQUASHFS_META_SLOTS; i &&
msblk->meta_index[msblk->next_meta_index].locked; i--)
msblk->next_meta_index = (msblk->next_meta_index + 1) %
SQUASHFS_META_SLOTS;
if (i == 0) {
TRACE("empty_meta_index: failed!\n");
goto failed;
}
TRACE("empty_meta_index: returned meta entry %d, %p\n",
msblk->next_meta_index,
&msblk->meta_index[msblk->next_meta_index]);
meta = &msblk->meta_index[msblk->next_meta_index];
msblk->next_meta_index = (msblk->next_meta_index + 1) %
SQUASHFS_META_SLOTS;
meta->inode_number = inode->i_ino;
meta->offset = offset;
meta->skip = skip;
meta->entries = 0;
meta->locked = 1;
failed:
mutex_unlock(&msblk->meta_index_mutex);
return meta;
}
static void release_meta_index(struct inode *inode, struct meta_index *meta)
{
struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
mutex_lock(&msblk->meta_index_mutex);
meta->locked = 0;
mutex_unlock(&msblk->meta_index_mutex);
}
/*
* Read the next n blocks from the block list, starting from
* metadata block <start_block, offset>.
*/
static long long read_indexes(struct super_block *sb, int n,
u64 *start_block, int *offset)
{
int err, i;
long long block = 0;
__le32 *blist = kmalloc(PAGE_CACHE_SIZE, GFP_KERNEL);
if (blist == NULL) {
ERROR("read_indexes: Failed to allocate block_list\n");
return -ENOMEM;
}
while (n) {
int blocks = min_t(int, n, PAGE_CACHE_SIZE >> 2);
err = squashfs_read_metadata(sb, blist, start_block,
offset, blocks << 2);
if (err < 0) {
ERROR("read_indexes: reading block [%llx:%x]\n",
*start_block, *offset);
goto failure;
}
for (i = 0; i < blocks; i++) {
int size = le32_to_cpu(blist[i]);
block += SQUASHFS_COMPRESSED_SIZE_BLOCK(size);
}
n -= blocks;
}
kfree(blist);
return block;
failure:
kfree(blist);
return err;
}
/*
* Each cache index slot has SQUASHFS_META_ENTRIES, each of which
* can cache one index -> datablock/blocklist-block mapping. We wish
* to distribute these over the length of the file, entry[0] maps index x,
* entry[1] maps index x + skip, entry[2] maps index x + 2 * skip, and so on.
* The larger the file, the greater the skip factor. The skip factor is
* limited to the size of the metadata cache (SQUASHFS_CACHED_BLKS) to ensure
* the number of metadata blocks that need to be read fits into the cache.
* If the skip factor is limited in this way then the file will use multiple
* slots.
*/
static inline int calculate_skip(int blocks)
{
int skip = blocks / ((SQUASHFS_META_ENTRIES + 1)
* SQUASHFS_META_INDEXES);
return min(SQUASHFS_CACHED_BLKS - 1, skip + 1);
}
/*
* Search and grow the index cache for the specified inode, returning the
* on-disk locations of the datablock and block list metadata block
* <index_block, index_offset> for index (scaled to nearest cache index).
*/
static int fill_meta_index(struct inode *inode, int index,
u64 *index_block, int *index_offset, u64 *data_block)
{
struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
int skip = calculate_skip(i_size_read(inode) >> msblk->block_log);
int offset = 0;
struct meta_index *meta;
struct meta_entry *meta_entry;
u64 cur_index_block = squashfs_i(inode)->block_list_start;
int cur_offset = squashfs_i(inode)->offset;
u64 cur_data_block = squashfs_i(inode)->start;
int err, i;
/*
* Scale index to cache index (cache slot entry)
*/
index /= SQUASHFS_META_INDEXES * skip;
while (offset < index) {
meta = locate_meta_index(inode, offset + 1, index);
if (meta == NULL) {
meta = empty_meta_index(inode, offset + 1, skip);
if (meta == NULL)
goto all_done;
} else {
offset = index < meta->offset + meta->entries ? index :
meta->offset + meta->entries - 1;
meta_entry = &meta->meta_entry[offset - meta->offset];
cur_index_block = meta_entry->index_block +
msblk->inode_table;
cur_offset = meta_entry->offset;
cur_data_block = meta_entry->data_block;
TRACE("get_meta_index: offset %d, meta->offset %d, "
"meta->entries %d\n", offset, meta->offset,
meta->entries);
TRACE("get_meta_index: index_block 0x%llx, offset 0x%x"
" data_block 0x%llx\n", cur_index_block,
cur_offset, cur_data_block);
}
/*
* If necessary grow cache slot by reading block list. Cache
* slot is extended up to index or to the end of the slot, in
* which case further slots will be used.
*/
for (i = meta->offset + meta->entries; i <= index &&
i < meta->offset + SQUASHFS_META_ENTRIES; i++) {
int blocks = skip * SQUASHFS_META_INDEXES;
long long res = read_indexes(inode->i_sb, blocks,
&cur_index_block, &cur_offset);
if (res < 0) {
if (meta->entries == 0)
/*
* Don't leave an empty slot on read
* error allocated to this inode...
*/
meta->inode_number = 0;
err = res;
goto failed;
}
cur_data_block += res;
meta_entry = &meta->meta_entry[i - meta->offset];
meta_entry->index_block = cur_index_block -
msblk->inode_table;
meta_entry->offset = cur_offset;
meta_entry->data_block = cur_data_block;
meta->entries++;
offset++;
}
TRACE("get_meta_index: meta->offset %d, meta->entries %d\n",
meta->offset, meta->entries);
release_meta_index(inode, meta);
}
all_done:
*index_block = cur_index_block;
*index_offset = cur_offset;
*data_block = cur_data_block;
/*
* Scale cache index (cache slot entry) to index
*/
return offset * SQUASHFS_META_INDEXES * skip;
failed:
release_meta_index(inode, meta);
return err;
}
/*
* Get the on-disk location and compressed size of the datablock
* specified by index. Fill_meta_index() does most of the work.
*/
static int read_blocklist(struct inode *inode, int index, u64 *block)
{
u64 start;
long long blks;
int offset;
__le32 size;
int res = fill_meta_index(inode, index, &start, &offset, block);
TRACE("read_blocklist: res %d, index %d, start 0x%llx, offset"
" 0x%x, block 0x%llx\n", res, index, start, offset,
*block);
if (res < 0)
return res;
/*
* res contains the index of the mapping returned by fill_meta_index(),
* this will likely be less than the desired index (because the
* meta_index cache works at a higher granularity). Read any
* extra block indexes needed.
*/
if (res < index) {
blks = read_indexes(inode->i_sb, index - res, &start, &offset);
if (blks < 0)
return (int) blks;
*block += blks;
}
/*
* Read length of block specified by index.
*/
res = squashfs_read_metadata(inode->i_sb, &size, &start, &offset,
sizeof(size));
if (res < 0)
return res;
return le32_to_cpu(size);
}
/* Copy data into page cache */
void squashfs_copy_cache(struct page *page, struct squashfs_cache_entry *buffer,
int bytes, int offset)
{
struct inode *inode = page->mapping->host;
struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
void *pageaddr;
int i, mask = (1 << (msblk->block_log - PAGE_CACHE_SHIFT)) - 1;
int start_index = page->index & ~mask, end_index = start_index | mask;
/*
* Loop copying datablock into pages. As the datablock likely covers
* many PAGE_CACHE_SIZE pages (default block size is 128 KiB) explicitly
* grab the pages from the page cache, except for the page that we've
* been called to fill.
*/
for (i = start_index; i <= end_index && bytes > 0; i++,
bytes -= PAGE_CACHE_SIZE, offset += PAGE_CACHE_SIZE) {
struct page *push_page;
int avail = buffer ? min_t(int, bytes, PAGE_CACHE_SIZE) : 0;
TRACE("bytes %d, i %d, available_bytes %d\n", bytes, i, avail);
push_page = (i == page->index) ? page :
grab_cache_page_nowait(page->mapping, i);
if (!push_page)
continue;
if (PageUptodate(push_page))
goto skip_page;
pageaddr = kmap_atomic(push_page);
squashfs_copy_data(pageaddr, buffer, offset, avail);
memset(pageaddr + avail, 0, PAGE_CACHE_SIZE - avail);
kunmap_atomic(pageaddr);
flush_dcache_page(push_page);
SetPageUptodate(push_page);
skip_page:
unlock_page(push_page);
if (i != page->index)
page_cache_release(push_page);
}
}
/* Read datablock stored packed inside a fragment (tail-end packed block) */
static int squashfs_readpage_fragment(struct page *page)
{
struct inode *inode = page->mapping->host;
struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
struct squashfs_cache_entry *buffer = squashfs_get_fragment(inode->i_sb,
squashfs_i(inode)->fragment_block,
squashfs_i(inode)->fragment_size);
int res = buffer->error;
if (res)
ERROR("Unable to read page, block %llx, size %x\n",
squashfs_i(inode)->fragment_block,
squashfs_i(inode)->fragment_size);
else
squashfs_copy_cache(page, buffer, i_size_read(inode) &
(msblk->block_size - 1),
squashfs_i(inode)->fragment_offset);
squashfs_cache_put(buffer);
return res;
}
static int squashfs_readpage_sparse(struct page *page, int index, int file_end)
{
struct inode *inode = page->mapping->host;
struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
int bytes = index == file_end ?
(i_size_read(inode) & (msblk->block_size - 1)) :
msblk->block_size;
squashfs_copy_cache(page, NULL, bytes, 0);
return 0;
}
static int squashfs_readpage(struct file *file, struct page *page)
{
struct inode *inode = page->mapping->host;
struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
int index = page->index >> (msblk->block_log - PAGE_CACHE_SHIFT);
int file_end = i_size_read(inode) >> msblk->block_log;
int res;
void *pageaddr;
TRACE("Entered squashfs_readpage, page index %lx, start block %llx\n",
page->index, squashfs_i(inode)->start);
if (page->index >= ((i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
PAGE_CACHE_SHIFT))
goto out;
if (index < file_end || squashfs_i(inode)->fragment_block ==
SQUASHFS_INVALID_BLK) {
u64 block = 0;
int bsize = read_blocklist(inode, index, &block);
if (bsize < 0)
goto error_out;
if (bsize == 0)
res = squashfs_readpage_sparse(page, index, file_end);
else
res = squashfs_readpage_block(page, block, bsize);
} else
res = squashfs_readpage_fragment(page);
if (!res)
return 0;
error_out:
SetPageError(page);
out:
pageaddr = kmap_atomic(page);
memset(pageaddr, 0, PAGE_CACHE_SIZE);
kunmap_atomic(pageaddr);
flush_dcache_page(page);
if (!PageError(page))
SetPageUptodate(page);
unlock_page(page);
return 0;
}
const struct address_space_operations squashfs_aops = {
.readpage = squashfs_readpage
};
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