android_kernel_xiaomi_sm8350/fs/ufs/util.c
Evgeniy Dushistov 10e5dce07e [PATCH] ufs: truncate should allocate block for last byte
This patch fixes buggy behaviour of UFS
in such kind of scenario:
open(, O_TRUNC...)
ftruncate(, 1024)
ftruncate(, 0)

Such a scenario causes ufs_panic and remount read-only.  This happen
because of according to specification UFS should always allocate block for
last byte, and many parts of our implementation rely on this, but
`ufs_truncate' doesn't care about this.

To make possible return error code and to know about old size, this patch
removes `truncate' from ufs inode_operations and uses `setattr' method to
call ufs_truncate.

Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-01 09:56:03 -07:00

290 lines
6.2 KiB
C

/*
* linux/fs/ufs/util.c
*
* Copyright (C) 1998
* Daniel Pirkl <daniel.pirkl@email.cz>
* Charles University, Faculty of Mathematics and Physics
*/
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/ufs_fs.h>
#include <linux/buffer_head.h>
#include "swab.h"
#include "util.h"
struct ufs_buffer_head * _ubh_bread_ (struct ufs_sb_private_info * uspi,
struct super_block *sb, u64 fragment, u64 size)
{
struct ufs_buffer_head * ubh;
unsigned i, j ;
u64 count = 0;
if (size & ~uspi->s_fmask)
return NULL;
count = size >> uspi->s_fshift;
if (count > UFS_MAXFRAG)
return NULL;
ubh = (struct ufs_buffer_head *)
kmalloc (sizeof (struct ufs_buffer_head), GFP_KERNEL);
if (!ubh)
return NULL;
ubh->fragment = fragment;
ubh->count = count;
for (i = 0; i < count; i++)
if (!(ubh->bh[i] = sb_bread(sb, fragment + i)))
goto failed;
for (; i < UFS_MAXFRAG; i++)
ubh->bh[i] = NULL;
return ubh;
failed:
for (j = 0; j < i; j++)
brelse (ubh->bh[j]);
kfree(ubh);
return NULL;
}
struct ufs_buffer_head * ubh_bread_uspi (struct ufs_sb_private_info * uspi,
struct super_block *sb, u64 fragment, u64 size)
{
unsigned i, j;
u64 count = 0;
if (size & ~uspi->s_fmask)
return NULL;
count = size >> uspi->s_fshift;
if (count <= 0 || count > UFS_MAXFRAG)
return NULL;
USPI_UBH(uspi)->fragment = fragment;
USPI_UBH(uspi)->count = count;
for (i = 0; i < count; i++)
if (!(USPI_UBH(uspi)->bh[i] = sb_bread(sb, fragment + i)))
goto failed;
for (; i < UFS_MAXFRAG; i++)
USPI_UBH(uspi)->bh[i] = NULL;
return USPI_UBH(uspi);
failed:
for (j = 0; j < i; j++)
brelse (USPI_UBH(uspi)->bh[j]);
return NULL;
}
void ubh_brelse (struct ufs_buffer_head * ubh)
{
unsigned i;
if (!ubh)
return;
for (i = 0; i < ubh->count; i++)
brelse (ubh->bh[i]);
kfree (ubh);
}
void ubh_brelse_uspi (struct ufs_sb_private_info * uspi)
{
unsigned i;
if (!USPI_UBH(uspi))
return;
for ( i = 0; i < USPI_UBH(uspi)->count; i++ ) {
brelse (USPI_UBH(uspi)->bh[i]);
USPI_UBH(uspi)->bh[i] = NULL;
}
}
void ubh_mark_buffer_dirty (struct ufs_buffer_head * ubh)
{
unsigned i;
if (!ubh)
return;
for ( i = 0; i < ubh->count; i++ )
mark_buffer_dirty (ubh->bh[i]);
}
void ubh_mark_buffer_uptodate (struct ufs_buffer_head * ubh, int flag)
{
unsigned i;
if (!ubh)
return;
if (flag) {
for ( i = 0; i < ubh->count; i++ )
set_buffer_uptodate (ubh->bh[i]);
} else {
for ( i = 0; i < ubh->count; i++ )
clear_buffer_uptodate (ubh->bh[i]);
}
}
void ubh_ll_rw_block(int rw, struct ufs_buffer_head *ubh)
{
if (!ubh)
return;
ll_rw_block(rw, ubh->count, ubh->bh);
}
void ubh_wait_on_buffer (struct ufs_buffer_head * ubh)
{
unsigned i;
if (!ubh)
return;
for ( i = 0; i < ubh->count; i++ )
wait_on_buffer (ubh->bh[i]);
}
void ubh_bforget (struct ufs_buffer_head * ubh)
{
unsigned i;
if (!ubh)
return;
for ( i = 0; i < ubh->count; i++ ) if ( ubh->bh[i] )
bforget (ubh->bh[i]);
}
int ubh_buffer_dirty (struct ufs_buffer_head * ubh)
{
unsigned i;
unsigned result = 0;
if (!ubh)
return 0;
for ( i = 0; i < ubh->count; i++ )
result |= buffer_dirty(ubh->bh[i]);
return result;
}
void _ubh_ubhcpymem_(struct ufs_sb_private_info * uspi,
unsigned char * mem, struct ufs_buffer_head * ubh, unsigned size)
{
unsigned len, bhno;
if (size > (ubh->count << uspi->s_fshift))
size = ubh->count << uspi->s_fshift;
bhno = 0;
while (size) {
len = min_t(unsigned int, size, uspi->s_fsize);
memcpy (mem, ubh->bh[bhno]->b_data, len);
mem += uspi->s_fsize;
size -= len;
bhno++;
}
}
void _ubh_memcpyubh_(struct ufs_sb_private_info * uspi,
struct ufs_buffer_head * ubh, unsigned char * mem, unsigned size)
{
unsigned len, bhno;
if (size > (ubh->count << uspi->s_fshift))
size = ubh->count << uspi->s_fshift;
bhno = 0;
while (size) {
len = min_t(unsigned int, size, uspi->s_fsize);
memcpy (ubh->bh[bhno]->b_data, mem, len);
mem += uspi->s_fsize;
size -= len;
bhno++;
}
}
dev_t
ufs_get_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi)
{
__fs32 fs32;
dev_t dev;
if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
fs32 = ufsi->i_u1.i_data[1];
else
fs32 = ufsi->i_u1.i_data[0];
fs32 = fs32_to_cpu(sb, fs32);
switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
case UFS_ST_SUNx86:
case UFS_ST_SUN:
if ((fs32 & 0xffff0000) == 0 ||
(fs32 & 0xffff0000) == 0xffff0000)
dev = old_decode_dev(fs32 & 0x7fff);
else
dev = MKDEV(sysv_major(fs32), sysv_minor(fs32));
break;
default:
dev = old_decode_dev(fs32);
break;
}
return dev;
}
void
ufs_set_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi, dev_t dev)
{
__fs32 fs32;
switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
case UFS_ST_SUNx86:
case UFS_ST_SUN:
fs32 = sysv_encode_dev(dev);
if ((fs32 & 0xffff8000) == 0) {
fs32 = old_encode_dev(dev);
}
break;
default:
fs32 = old_encode_dev(dev);
break;
}
fs32 = cpu_to_fs32(sb, fs32);
if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
ufsi->i_u1.i_data[1] = fs32;
else
ufsi->i_u1.i_data[0] = fs32;
}
/**
* ufs_get_locked_page() - locate, pin and lock a pagecache page, if not exist
* read it from disk.
* @mapping: the address_space to search
* @index: the page index
*
* Locates the desired pagecache page, if not exist we'll read it,
* locks it, increments its reference
* count and returns its address.
*
*/
struct page *ufs_get_locked_page(struct address_space *mapping,
pgoff_t index)
{
struct page *page;
try_again:
page = find_lock_page(mapping, index);
if (!page) {
page = read_cache_page(mapping, index,
(filler_t*)mapping->a_ops->readpage,
NULL);
if (IS_ERR(page)) {
printk(KERN_ERR "ufs_change_blocknr: "
"read_cache_page error: ino %lu, index: %lu\n",
mapping->host->i_ino, index);
goto out;
}
lock_page(page);
if (!PageUptodate(page) || PageError(page)) {
unlock_page(page);
page_cache_release(page);
printk(KERN_ERR "ufs_change_blocknr: "
"can not read page: ino %lu, index: %lu\n",
mapping->host->i_ino, index);
page = ERR_PTR(-EIO);
goto out;
}
}
if (unlikely(!page->mapping || !page_has_buffers(page))) {
unlock_page(page);
page_cache_release(page);
goto try_again;/*we really need these buffers*/
}
out:
return page;
}