WSL2-Linux-Kernel/fs/ufs/balloc.c

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27 KiB
C
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/*
* linux/fs/ufs/balloc.c
*
* Copyright (C) 1998
* Daniel Pirkl <daniel.pirkl@email.cz>
* Charles University, Faculty of Mathematics and Physics
*
* UFS2 write support Evgeniy Dushistov <dushistov@mail.ru>, 2007
*/
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/time.h>
#include <linux/string.h>
#include <linux/buffer_head.h>
#include <linux/capability.h>
#include <linux/bitops.h>
#include <asm/byteorder.h>
#include "ufs_fs.h"
#include "ufs.h"
#include "swab.h"
#include "util.h"
#define INVBLOCK ((u64)-1L)
static u64 ufs_add_fragments(struct inode *, u64, unsigned, unsigned, int *);
static u64 ufs_alloc_fragments(struct inode *, unsigned, u64, unsigned, int *);
static u64 ufs_alloccg_block(struct inode *, struct ufs_cg_private_info *, u64, int *);
static u64 ufs_bitmap_search (struct super_block *, struct ufs_cg_private_info *, u64, unsigned);
static unsigned char ufs_fragtable_8fpb[], ufs_fragtable_other[];
static void ufs_clusteracct(struct super_block *, struct ufs_cg_private_info *, unsigned, int);
/*
* Free 'count' fragments from fragment number 'fragment'
*/
void ufs_free_fragments(struct inode *inode, u64 fragment, unsigned count)
{
struct super_block * sb;
struct ufs_sb_private_info * uspi;
struct ufs_super_block_first * usb1;
struct ufs_cg_private_info * ucpi;
struct ufs_cylinder_group * ucg;
unsigned cgno, bit, end_bit, bbase, blkmap, i;
u64 blkno;
sb = inode->i_sb;
uspi = UFS_SB(sb)->s_uspi;
usb1 = ubh_get_usb_first(uspi);
UFSD("ENTER, fragment %llu, count %u\n",
(unsigned long long)fragment, count);
if (ufs_fragnum(fragment) + count > uspi->s_fpg)
ufs_error (sb, "ufs_free_fragments", "internal error");
lock_super(sb);
cgno = ufs_dtog(uspi, fragment);
bit = ufs_dtogd(uspi, fragment);
if (cgno >= uspi->s_ncg) {
ufs_panic (sb, "ufs_free_fragments", "freeing blocks are outside device");
goto failed;
}
ucpi = ufs_load_cylinder (sb, cgno);
if (!ucpi)
goto failed;
ucg = ubh_get_ucg (UCPI_UBH(ucpi));
if (!ufs_cg_chkmagic(sb, ucg)) {
ufs_panic (sb, "ufs_free_fragments", "internal error, bad magic number on cg %u", cgno);
goto failed;
}
end_bit = bit + count;
bbase = ufs_blknum (bit);
blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
ufs_fragacct (sb, blkmap, ucg->cg_frsum, -1);
for (i = bit; i < end_bit; i++) {
if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, i))
ubh_setbit (UCPI_UBH(ucpi), ucpi->c_freeoff, i);
else
ufs_error (sb, "ufs_free_fragments",
"bit already cleared for fragment %u", i);
}
fs32_add(sb, &ucg->cg_cs.cs_nffree, count);
uspi->cs_total.cs_nffree += count;
fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
ufs_fragacct(sb, blkmap, ucg->cg_frsum, 1);
/*
* Trying to reassemble free fragments into block
*/
blkno = ufs_fragstoblks (bbase);
if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
fs32_sub(sb, &ucg->cg_cs.cs_nffree, uspi->s_fpb);
uspi->cs_total.cs_nffree -= uspi->s_fpb;
fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, uspi->s_fpb);
if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
ufs_clusteracct (sb, ucpi, blkno, 1);
fs32_add(sb, &ucg->cg_cs.cs_nbfree, 1);
uspi->cs_total.cs_nbfree++;
fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nbfree, 1);
if (uspi->fs_magic != UFS2_MAGIC) {
unsigned cylno = ufs_cbtocylno (bbase);
fs16_add(sb, &ubh_cg_blks(ucpi, cylno,
ufs_cbtorpos(bbase)), 1);
fs32_add(sb, &ubh_cg_blktot(ucpi, cylno), 1);
}
}
ubh_mark_buffer_dirty (USPI_UBH(uspi));
ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
if (sb->s_flags & MS_SYNCHRONOUS)
ubh_sync_block(UCPI_UBH(ucpi));
sb->s_dirt = 1;
unlock_super (sb);
UFSD("EXIT\n");
return;
failed:
unlock_super (sb);
UFSD("EXIT (FAILED)\n");
return;
}
/*
* Free 'count' fragments from fragment number 'fragment' (free whole blocks)
*/
void ufs_free_blocks(struct inode *inode, u64 fragment, unsigned count)
{
struct super_block * sb;
struct ufs_sb_private_info * uspi;
struct ufs_super_block_first * usb1;
struct ufs_cg_private_info * ucpi;
struct ufs_cylinder_group * ucg;
unsigned overflow, cgno, bit, end_bit, i;
u64 blkno;
sb = inode->i_sb;
uspi = UFS_SB(sb)->s_uspi;
usb1 = ubh_get_usb_first(uspi);
UFSD("ENTER, fragment %llu, count %u\n",
(unsigned long long)fragment, count);
if ((fragment & uspi->s_fpbmask) || (count & uspi->s_fpbmask)) {
ufs_error (sb, "ufs_free_blocks", "internal error, "
"fragment %llu, count %u\n",
(unsigned long long)fragment, count);
goto failed;
}
lock_super(sb);
do_more:
overflow = 0;
cgno = ufs_dtog(uspi, fragment);
bit = ufs_dtogd(uspi, fragment);
if (cgno >= uspi->s_ncg) {
ufs_panic (sb, "ufs_free_blocks", "freeing blocks are outside device");
goto failed_unlock;
}
end_bit = bit + count;
if (end_bit > uspi->s_fpg) {
overflow = bit + count - uspi->s_fpg;
count -= overflow;
end_bit -= overflow;
}
ucpi = ufs_load_cylinder (sb, cgno);
if (!ucpi)
goto failed_unlock;
ucg = ubh_get_ucg (UCPI_UBH(ucpi));
if (!ufs_cg_chkmagic(sb, ucg)) {
ufs_panic (sb, "ufs_free_blocks", "internal error, bad magic number on cg %u", cgno);
goto failed_unlock;
}
for (i = bit; i < end_bit; i += uspi->s_fpb) {
blkno = ufs_fragstoblks(i);
if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
ufs_error(sb, "ufs_free_blocks", "freeing free fragment");
}
ubh_setblock(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno);
if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
ufs_clusteracct (sb, ucpi, blkno, 1);
fs32_add(sb, &ucg->cg_cs.cs_nbfree, 1);
uspi->cs_total.cs_nbfree++;
fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nbfree, 1);
if (uspi->fs_magic != UFS2_MAGIC) {
unsigned cylno = ufs_cbtocylno(i);
fs16_add(sb, &ubh_cg_blks(ucpi, cylno,
ufs_cbtorpos(i)), 1);
fs32_add(sb, &ubh_cg_blktot(ucpi, cylno), 1);
}
}
ubh_mark_buffer_dirty (USPI_UBH(uspi));
ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
if (sb->s_flags & MS_SYNCHRONOUS)
ubh_sync_block(UCPI_UBH(ucpi));
if (overflow) {
fragment += count;
count = overflow;
goto do_more;
}
sb->s_dirt = 1;
unlock_super (sb);
UFSD("EXIT\n");
return;
failed_unlock:
unlock_super (sb);
failed:
UFSD("EXIT (FAILED)\n");
return;
}
/*
* Modify inode page cache in such way:
* have - blocks with b_blocknr equal to oldb...oldb+count-1
* get - blocks with b_blocknr equal to newb...newb+count-1
* also we suppose that oldb...oldb+count-1 blocks
* situated at the end of file.
*
* We can come here from ufs_writepage or ufs_prepare_write,
* locked_page is argument of these functions, so we already lock it.
*/
static void ufs_change_blocknr(struct inode *inode, sector_t beg,
unsigned int count, sector_t oldb,
sector_t newb, struct page *locked_page)
{
const unsigned blks_per_page =
1 << (PAGE_CACHE_SHIFT - inode->i_blkbits);
const unsigned mask = blks_per_page - 1;
struct address_space * const mapping = inode->i_mapping;
pgoff_t index, cur_index, last_index;
unsigned pos, j, lblock;
sector_t end, i;
struct page *page;
struct buffer_head *head, *bh;
UFSD("ENTER, ino %lu, count %u, oldb %llu, newb %llu\n",
inode->i_ino, count,
(unsigned long long)oldb, (unsigned long long)newb);
BUG_ON(!locked_page);
BUG_ON(!PageLocked(locked_page));
cur_index = locked_page->index;
end = count + beg;
last_index = end >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
for (i = beg; i < end; i = (i | mask) + 1) {
index = i >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
if (likely(cur_index != index)) {
page = ufs_get_locked_page(mapping, index);
if (!page)/* it was truncated */
continue;
if (IS_ERR(page)) {/* or EIO */
ufs_error(inode->i_sb, __func__,
"read of page %llu failed\n",
(unsigned long long)index);
continue;
}
} else
page = locked_page;
head = page_buffers(page);
bh = head;
pos = i & mask;
for (j = 0; j < pos; ++j)
bh = bh->b_this_page;
if (unlikely(index == last_index))
lblock = end & mask;
else
lblock = blks_per_page;
do {
if (j >= lblock)
break;
pos = (i - beg) + j;
if (!buffer_mapped(bh))
map_bh(bh, inode->i_sb, oldb + pos);
if (!buffer_uptodate(bh)) {
ll_rw_block(READ, 1, &bh);
wait_on_buffer(bh);
if (!buffer_uptodate(bh)) {
ufs_error(inode->i_sb, __func__,
"read of block failed\n");
break;
}
}
UFSD(" change from %llu to %llu, pos %u\n",
(unsigned long long)(pos + oldb),
(unsigned long long)(pos + newb), pos);
bh->b_blocknr = newb + pos;
unmap_underlying_metadata(bh->b_bdev,
bh->b_blocknr);
mark_buffer_dirty(bh);
++j;
bh = bh->b_this_page;
} while (bh != head);
if (likely(cur_index != index))
ufs_put_locked_page(page);
}
UFSD("EXIT\n");
}
static void ufs_clear_frags(struct inode *inode, sector_t beg, unsigned int n,
int sync)
{
struct buffer_head *bh;
sector_t end = beg + n;
for (; beg < end; ++beg) {
bh = sb_getblk(inode->i_sb, beg);
lock_buffer(bh);
memset(bh->b_data, 0, inode->i_sb->s_blocksize);
set_buffer_uptodate(bh);
mark_buffer_dirty(bh);
unlock_buffer(bh);
if (IS_SYNC(inode) || sync)
sync_dirty_buffer(bh);
brelse(bh);
}
}
u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
u64 goal, unsigned count, int *err,
struct page *locked_page)
{
struct super_block * sb;
struct ufs_sb_private_info * uspi;
struct ufs_super_block_first * usb1;
unsigned cgno, oldcount, newcount;
u64 tmp, request, result;
UFSD("ENTER, ino %lu, fragment %llu, goal %llu, count %u\n",
inode->i_ino, (unsigned long long)fragment,
(unsigned long long)goal, count);
sb = inode->i_sb;
uspi = UFS_SB(sb)->s_uspi;
usb1 = ubh_get_usb_first(uspi);
*err = -ENOSPC;
lock_super (sb);
tmp = ufs_data_ptr_to_cpu(sb, p);
if (count + ufs_fragnum(fragment) > uspi->s_fpb) {
ufs_warning(sb, "ufs_new_fragments", "internal warning"
" fragment %llu, count %u",
(unsigned long long)fragment, count);
count = uspi->s_fpb - ufs_fragnum(fragment);
}
oldcount = ufs_fragnum (fragment);
newcount = oldcount + count;
/*
* Somebody else has just allocated our fragments
*/
if (oldcount) {
if (!tmp) {
ufs_error(sb, "ufs_new_fragments", "internal error, "
"fragment %llu, tmp %llu\n",
(unsigned long long)fragment,
(unsigned long long)tmp);
unlock_super(sb);
return INVBLOCK;
}
if (fragment < UFS_I(inode)->i_lastfrag) {
UFSD("EXIT (ALREADY ALLOCATED)\n");
unlock_super (sb);
return 0;
}
}
else {
if (tmp) {
UFSD("EXIT (ALREADY ALLOCATED)\n");
unlock_super(sb);
return 0;
}
}
/*
* There is not enough space for user on the device
*/
if (!capable(CAP_SYS_RESOURCE) && ufs_freespace(uspi, UFS_MINFREE) <= 0) {
unlock_super (sb);
UFSD("EXIT (FAILED)\n");
return 0;
}
if (goal >= uspi->s_size)
goal = 0;
if (goal == 0)
cgno = ufs_inotocg (inode->i_ino);
else
cgno = ufs_dtog(uspi, goal);
/*
* allocate new fragment
*/
if (oldcount == 0) {
result = ufs_alloc_fragments (inode, cgno, goal, count, err);
if (result) {
ufs_cpu_to_data_ptr(sb, p, result);
*err = 0;
UFS_I(inode)->i_lastfrag =
max_t(u32, UFS_I(inode)->i_lastfrag,
fragment + count);
ufs_clear_frags(inode, result + oldcount,
newcount - oldcount, locked_page != NULL);
}
unlock_super(sb);
UFSD("EXIT, result %llu\n", (unsigned long long)result);
return result;
}
/*
* resize block
*/
result = ufs_add_fragments (inode, tmp, oldcount, newcount, err);
if (result) {
*err = 0;
UFS_I(inode)->i_lastfrag = max_t(u32, UFS_I(inode)->i_lastfrag, fragment + count);
ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
locked_page != NULL);
unlock_super(sb);
UFSD("EXIT, result %llu\n", (unsigned long long)result);
return result;
}
/*
* allocate new block and move data
*/
switch (fs32_to_cpu(sb, usb1->fs_optim)) {
case UFS_OPTSPACE:
request = newcount;
if (uspi->s_minfree < 5 || uspi->cs_total.cs_nffree
> uspi->s_dsize * uspi->s_minfree / (2 * 100))
break;
usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
break;
default:
usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
case UFS_OPTTIME:
request = uspi->s_fpb;
if (uspi->cs_total.cs_nffree < uspi->s_dsize *
(uspi->s_minfree - 2) / 100)
break;
usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
break;
}
result = ufs_alloc_fragments (inode, cgno, goal, request, err);
if (result) {
ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
locked_page != NULL);
ufs_change_blocknr(inode, fragment - oldcount, oldcount,
uspi->s_sbbase + tmp,
uspi->s_sbbase + result, locked_page);
ufs_cpu_to_data_ptr(sb, p, result);
*err = 0;
UFS_I(inode)->i_lastfrag = max_t(u32, UFS_I(inode)->i_lastfrag, fragment + count);
unlock_super(sb);
if (newcount < request)
ufs_free_fragments (inode, result + newcount, request - newcount);
ufs_free_fragments (inode, tmp, oldcount);
UFSD("EXIT, result %llu\n", (unsigned long long)result);
return result;
}
unlock_super(sb);
UFSD("EXIT (FAILED)\n");
return 0;
}
static u64 ufs_add_fragments(struct inode *inode, u64 fragment,
unsigned oldcount, unsigned newcount, int *err)
{
struct super_block * sb;
struct ufs_sb_private_info * uspi;
struct ufs_super_block_first * usb1;
struct ufs_cg_private_info * ucpi;
struct ufs_cylinder_group * ucg;
unsigned cgno, fragno, fragoff, count, fragsize, i;
UFSD("ENTER, fragment %llu, oldcount %u, newcount %u\n",
(unsigned long long)fragment, oldcount, newcount);
sb = inode->i_sb;
uspi = UFS_SB(sb)->s_uspi;
usb1 = ubh_get_usb_first (uspi);
count = newcount - oldcount;
cgno = ufs_dtog(uspi, fragment);
if (fs32_to_cpu(sb, UFS_SB(sb)->fs_cs(cgno).cs_nffree) < count)
return 0;
if ((ufs_fragnum (fragment) + newcount) > uspi->s_fpb)
return 0;
ucpi = ufs_load_cylinder (sb, cgno);
if (!ucpi)
return 0;
ucg = ubh_get_ucg (UCPI_UBH(ucpi));
if (!ufs_cg_chkmagic(sb, ucg)) {
ufs_panic (sb, "ufs_add_fragments",
"internal error, bad magic number on cg %u", cgno);
return 0;
}
fragno = ufs_dtogd(uspi, fragment);
fragoff = ufs_fragnum (fragno);
for (i = oldcount; i < newcount; i++)
if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i))
return 0;
/*
* Block can be extended
*/
ucg->cg_time = cpu_to_fs32(sb, get_seconds());
for (i = newcount; i < (uspi->s_fpb - fragoff); i++)
if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i))
break;
fragsize = i - oldcount;
if (!fs32_to_cpu(sb, ucg->cg_frsum[fragsize]))
ufs_panic (sb, "ufs_add_fragments",
"internal error or corrupted bitmap on cg %u", cgno);
fs32_sub(sb, &ucg->cg_frsum[fragsize], 1);
if (fragsize != count)
fs32_add(sb, &ucg->cg_frsum[fragsize - count], 1);
for (i = oldcount; i < newcount; i++)
ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i);
fs32_sub(sb, &ucg->cg_cs.cs_nffree, count);
fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
uspi->cs_total.cs_nffree -= count;
ubh_mark_buffer_dirty (USPI_UBH(uspi));
ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
if (sb->s_flags & MS_SYNCHRONOUS)
ubh_sync_block(UCPI_UBH(ucpi));
sb->s_dirt = 1;
UFSD("EXIT, fragment %llu\n", (unsigned long long)fragment);
return fragment;
}
#define UFS_TEST_FREE_SPACE_CG \
ucg = (struct ufs_cylinder_group *) UFS_SB(sb)->s_ucg[cgno]->b_data; \
if (fs32_to_cpu(sb, ucg->cg_cs.cs_nbfree)) \
goto cg_found; \
for (k = count; k < uspi->s_fpb; k++) \
if (fs32_to_cpu(sb, ucg->cg_frsum[k])) \
goto cg_found;
static u64 ufs_alloc_fragments(struct inode *inode, unsigned cgno,
u64 goal, unsigned count, int *err)
{
struct super_block * sb;
struct ufs_sb_private_info * uspi;
struct ufs_super_block_first * usb1;
struct ufs_cg_private_info * ucpi;
struct ufs_cylinder_group * ucg;
unsigned oldcg, i, j, k, allocsize;
u64 result;
UFSD("ENTER, ino %lu, cgno %u, goal %llu, count %u\n",
inode->i_ino, cgno, (unsigned long long)goal, count);
sb = inode->i_sb;
uspi = UFS_SB(sb)->s_uspi;
usb1 = ubh_get_usb_first(uspi);
oldcg = cgno;
/*
* 1. searching on preferred cylinder group
*/
UFS_TEST_FREE_SPACE_CG
/*
* 2. quadratic rehash
*/
for (j = 1; j < uspi->s_ncg; j *= 2) {
cgno += j;
if (cgno >= uspi->s_ncg)
cgno -= uspi->s_ncg;
UFS_TEST_FREE_SPACE_CG
}
/*
* 3. brute force search
* We start at i = 2 ( 0 is checked at 1.step, 1 at 2.step )
*/
cgno = (oldcg + 1) % uspi->s_ncg;
for (j = 2; j < uspi->s_ncg; j++) {
cgno++;
if (cgno >= uspi->s_ncg)
cgno = 0;
UFS_TEST_FREE_SPACE_CG
}
UFSD("EXIT (FAILED)\n");
return 0;
cg_found:
ucpi = ufs_load_cylinder (sb, cgno);
if (!ucpi)
return 0;
ucg = ubh_get_ucg (UCPI_UBH(ucpi));
if (!ufs_cg_chkmagic(sb, ucg))
ufs_panic (sb, "ufs_alloc_fragments",
"internal error, bad magic number on cg %u", cgno);
ucg->cg_time = cpu_to_fs32(sb, get_seconds());
if (count == uspi->s_fpb) {
result = ufs_alloccg_block (inode, ucpi, goal, err);
if (result == INVBLOCK)
return 0;
goto succed;
}
for (allocsize = count; allocsize < uspi->s_fpb; allocsize++)
if (fs32_to_cpu(sb, ucg->cg_frsum[allocsize]) != 0)
break;
if (allocsize == uspi->s_fpb) {
result = ufs_alloccg_block (inode, ucpi, goal, err);
if (result == INVBLOCK)
return 0;
goal = ufs_dtogd(uspi, result);
for (i = count; i < uspi->s_fpb; i++)
ubh_setbit (UCPI_UBH(ucpi), ucpi->c_freeoff, goal + i);
i = uspi->s_fpb - count;
fs32_add(sb, &ucg->cg_cs.cs_nffree, i);
uspi->cs_total.cs_nffree += i;
fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, i);
fs32_add(sb, &ucg->cg_frsum[i], 1);
goto succed;
}
result = ufs_bitmap_search (sb, ucpi, goal, allocsize);
if (result == INVBLOCK)
return 0;
for (i = 0; i < count; i++)
ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_freeoff, result + i);
fs32_sub(sb, &ucg->cg_cs.cs_nffree, count);
uspi->cs_total.cs_nffree -= count;
fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
fs32_sub(sb, &ucg->cg_frsum[allocsize], 1);
if (count != allocsize)
fs32_add(sb, &ucg->cg_frsum[allocsize - count], 1);
succed:
ubh_mark_buffer_dirty (USPI_UBH(uspi));
ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
if (sb->s_flags & MS_SYNCHRONOUS)
ubh_sync_block(UCPI_UBH(ucpi));
sb->s_dirt = 1;
result += cgno * uspi->s_fpg;
UFSD("EXIT3, result %llu\n", (unsigned long long)result);
return result;
}
static u64 ufs_alloccg_block(struct inode *inode,
struct ufs_cg_private_info *ucpi,
u64 goal, int *err)
{
struct super_block * sb;
struct ufs_sb_private_info * uspi;
struct ufs_super_block_first * usb1;
struct ufs_cylinder_group * ucg;
u64 result, blkno;
UFSD("ENTER, goal %llu\n", (unsigned long long)goal);
sb = inode->i_sb;
uspi = UFS_SB(sb)->s_uspi;
usb1 = ubh_get_usb_first(uspi);
ucg = ubh_get_ucg(UCPI_UBH(ucpi));
if (goal == 0) {
goal = ucpi->c_rotor;
goto norot;
}
goal = ufs_blknum (goal);
goal = ufs_dtogd(uspi, goal);
/*
* If the requested block is available, use it.
*/
if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, ufs_fragstoblks(goal))) {
result = goal;
goto gotit;
}
norot:
result = ufs_bitmap_search (sb, ucpi, goal, uspi->s_fpb);
if (result == INVBLOCK)
return INVBLOCK;
ucpi->c_rotor = result;
gotit:
blkno = ufs_fragstoblks(result);
ubh_clrblock (UCPI_UBH(ucpi), ucpi->c_freeoff, blkno);
if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
ufs_clusteracct (sb, ucpi, blkno, -1);
fs32_sub(sb, &ucg->cg_cs.cs_nbfree, 1);
uspi->cs_total.cs_nbfree--;
fs32_sub(sb, &UFS_SB(sb)->fs_cs(ucpi->c_cgx).cs_nbfree, 1);
if (uspi->fs_magic != UFS2_MAGIC) {
unsigned cylno = ufs_cbtocylno((unsigned)result);
fs16_sub(sb, &ubh_cg_blks(ucpi, cylno,
ufs_cbtorpos((unsigned)result)), 1);
fs32_sub(sb, &ubh_cg_blktot(ucpi, cylno), 1);
}
UFSD("EXIT, result %llu\n", (unsigned long long)result);
return result;
}
static unsigned ubh_scanc(struct ufs_sb_private_info *uspi,
struct ufs_buffer_head *ubh,
unsigned begin, unsigned size,
unsigned char *table, unsigned char mask)
{
unsigned rest, offset;
unsigned char *cp;
offset = begin & ~uspi->s_fmask;
begin >>= uspi->s_fshift;
for (;;) {
if ((offset + size) < uspi->s_fsize)
rest = size;
else
rest = uspi->s_fsize - offset;
size -= rest;
cp = ubh->bh[begin]->b_data + offset;
while ((table[*cp++] & mask) == 0 && --rest)
;
if (rest || !size)
break;
begin++;
offset = 0;
}
return (size + rest);
}
/*
* Find a block of the specified size in the specified cylinder group.
* @sp: pointer to super block
* @ucpi: pointer to cylinder group info
* @goal: near which block we want find new one
* @count: specified size
*/
static u64 ufs_bitmap_search(struct super_block *sb,
struct ufs_cg_private_info *ucpi,
u64 goal, unsigned count)
{
/*
* Bit patterns for identifying fragments in the block map
* used as ((map & mask_arr) == want_arr)
*/
static const int mask_arr[9] = {
0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff
};
static const int want_arr[9] = {
0x0, 0x2, 0x6, 0xe, 0x1e, 0x3e, 0x7e, 0xfe, 0x1fe
};
struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
struct ufs_super_block_first *usb1;
struct ufs_cylinder_group *ucg;
unsigned start, length, loc;
unsigned pos, want, blockmap, mask, end;
u64 result;
UFSD("ENTER, cg %u, goal %llu, count %u\n", ucpi->c_cgx,
(unsigned long long)goal, count);
usb1 = ubh_get_usb_first (uspi);
ucg = ubh_get_ucg(UCPI_UBH(ucpi));
if (goal)
start = ufs_dtogd(uspi, goal) >> 3;
else
start = ucpi->c_frotor >> 3;
length = ((uspi->s_fpg + 7) >> 3) - start;
loc = ubh_scanc(uspi, UCPI_UBH(ucpi), ucpi->c_freeoff + start, length,
(uspi->s_fpb == 8) ? ufs_fragtable_8fpb : ufs_fragtable_other,
1 << (count - 1 + (uspi->s_fpb & 7)));
if (loc == 0) {
length = start + 1;
loc = ubh_scanc(uspi, UCPI_UBH(ucpi), ucpi->c_freeoff, length,
(uspi->s_fpb == 8) ? ufs_fragtable_8fpb :
ufs_fragtable_other,
1 << (count - 1 + (uspi->s_fpb & 7)));
if (loc == 0) {
ufs_error(sb, "ufs_bitmap_search",
"bitmap corrupted on cg %u, start %u,"
" length %u, count %u, freeoff %u\n",
ucpi->c_cgx, start, length, count,
ucpi->c_freeoff);
return INVBLOCK;
}
start = 0;
}
result = (start + length - loc) << 3;
ucpi->c_frotor = result;
/*
* found the byte in the map
*/
for (end = result + 8; result < end; result += uspi->s_fpb) {
blockmap = ubh_blkmap(UCPI_UBH(ucpi), ucpi->c_freeoff, result);
blockmap <<= 1;
mask = mask_arr[count];
want = want_arr[count];
for (pos = 0; pos <= uspi->s_fpb - count; pos++) {
if ((blockmap & mask) == want) {
UFSD("EXIT, result %llu\n",
(unsigned long long)result);
return result + pos;
}
mask <<= 1;
want <<= 1;
}
}
ufs_error(sb, "ufs_bitmap_search", "block not in map on cg %u\n",
ucpi->c_cgx);
UFSD("EXIT (FAILED)\n");
return INVBLOCK;
}
static void ufs_clusteracct(struct super_block * sb,
struct ufs_cg_private_info * ucpi, unsigned blkno, int cnt)
{
struct ufs_sb_private_info * uspi;
int i, start, end, forw, back;
uspi = UFS_SB(sb)->s_uspi;
if (uspi->s_contigsumsize <= 0)
return;
if (cnt > 0)
ubh_setbit(UCPI_UBH(ucpi), ucpi->c_clusteroff, blkno);
else
ubh_clrbit(UCPI_UBH(ucpi), ucpi->c_clusteroff, blkno);
/*
* Find the size of the cluster going forward.
*/
start = blkno + 1;
end = start + uspi->s_contigsumsize;
if ( end >= ucpi->c_nclusterblks)
end = ucpi->c_nclusterblks;
i = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_clusteroff, end, start);
if (i > end)
i = end;
forw = i - start;
/*
* Find the size of the cluster going backward.
*/
start = blkno - 1;
end = start - uspi->s_contigsumsize;
if (end < 0 )
end = -1;
i = ubh_find_last_zero_bit (UCPI_UBH(ucpi), ucpi->c_clusteroff, start, end);
if ( i < end)
i = end;
back = start - i;
/*
* Account for old cluster and the possibly new forward and
* back clusters.
*/
i = back + forw + 1;
if (i > uspi->s_contigsumsize)
i = uspi->s_contigsumsize;
fs32_add(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (i << 2)), cnt);
if (back > 0)
fs32_sub(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (back << 2)), cnt);
if (forw > 0)
fs32_sub(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (forw << 2)), cnt);
}
static unsigned char ufs_fragtable_8fpb[] = {
0x00, 0x01, 0x01, 0x02, 0x01, 0x01, 0x02, 0x04, 0x01, 0x01, 0x01, 0x03, 0x02, 0x03, 0x04, 0x08,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x02, 0x03, 0x03, 0x02, 0x04, 0x05, 0x08, 0x10,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x04, 0x05, 0x05, 0x06, 0x08, 0x09, 0x10, 0x20,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0A,
0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 0x08, 0x09, 0x09, 0x0A, 0x10, 0x11, 0x20, 0x40,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 0x05, 0x05, 0x05, 0x07, 0x09, 0x09, 0x11, 0x21,
0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0A,
0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 0x02, 0x03, 0x03, 0x02, 0x06, 0x07, 0x0A, 0x12,
0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 0x05, 0x05, 0x05, 0x07, 0x06, 0x07, 0x04, 0x0C,
0x08, 0x09, 0x09, 0x0A, 0x09, 0x09, 0x0A, 0x0C, 0x10, 0x11, 0x11, 0x12, 0x20, 0x21, 0x40, 0x80,
};
static unsigned char ufs_fragtable_other[] = {
0x00, 0x16, 0x16, 0x2A, 0x16, 0x16, 0x26, 0x4E, 0x16, 0x16, 0x16, 0x3E, 0x2A, 0x3E, 0x4E, 0x8A,
0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
0x2A, 0x3E, 0x3E, 0x2A, 0x3E, 0x3E, 0x2E, 0x6E, 0x3E, 0x3E, 0x3E, 0x3E, 0x2A, 0x3E, 0x6E, 0xAA,
0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
0x26, 0x36, 0x36, 0x2E, 0x36, 0x36, 0x26, 0x6E, 0x36, 0x36, 0x36, 0x3E, 0x2E, 0x3E, 0x6E, 0xAE,
0x4E, 0x5E, 0x5E, 0x6E, 0x5E, 0x5E, 0x6E, 0x4E, 0x5E, 0x5E, 0x5E, 0x7E, 0x6E, 0x7E, 0x4E, 0xCE,
0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0xBE,
0x2A, 0x3E, 0x3E, 0x2A, 0x3E, 0x3E, 0x2E, 0x6E, 0x3E, 0x3E, 0x3E, 0x3E, 0x2A, 0x3E, 0x6E, 0xAA,
0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0xBE,
0x4E, 0x5E, 0x5E, 0x6E, 0x5E, 0x5E, 0x6E, 0x4E, 0x5E, 0x5E, 0x5E, 0x7E, 0x6E, 0x7E, 0x4E, 0xCE,
0x8A, 0x9E, 0x9E, 0xAA, 0x9E, 0x9E, 0xAE, 0xCE, 0x9E, 0x9E, 0x9E, 0xBE, 0xAA, 0xBE, 0xCE, 0x8A,
};