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-rw-r--r--sys/gnu/fs/ext2fs/ext2_linux_balloc.c624
1 files changed, 0 insertions, 624 deletions
diff --git a/sys/gnu/fs/ext2fs/ext2_linux_balloc.c b/sys/gnu/fs/ext2fs/ext2_linux_balloc.c
deleted file mode 100644
index 2c9a6da..0000000
--- a/sys/gnu/fs/ext2fs/ext2_linux_balloc.c
+++ /dev/null
@@ -1,624 +0,0 @@
-/*-
- * modified for Lites 1.1
- *
- * Aug 1995, Godmar Back (gback@cs.utah.edu)
- * University of Utah, Department of Computer Science
- *
- * $FreeBSD$
- */
-/*-
- * linux/fs/ext2/balloc.c
- *
- * Copyright (C) 1992, 1993, 1994, 1995
- * Remy Card (card@masi.ibp.fr)
- * Laboratoire MASI - Institut Blaise Pascal
- * Universite Pierre et Marie Curie (Paris VI)
- *
- * Enhanced block allocation by Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
- *
- * 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 of the License..
- *
- * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- */
-
-/*
- * The free blocks are managed by bitmaps. A file system contains several
- * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
- * block for inodes, N blocks for the inode table and data blocks.
- *
- * The file system contains group descriptors which are located after the
- * super block. Each descriptor contains the number of the bitmap block and
- * the free blocks count in the block. The descriptors are loaded in memory
- * when a file system is mounted (see ext2_read_super).
- */
-
-#include <sys/param.h>
-#include <sys/systm.h>
-#include <sys/bio.h>
-#include <sys/buf.h>
-#include <sys/mount.h>
-#include <sys/vnode.h>
-
-#include <gnu/fs/ext2fs/inode.h>
-#include <gnu/fs/ext2fs/ext2_mount.h>
-#include <gnu/fs/ext2fs/ext2_extern.h>
-#include <gnu/fs/ext2fs/ext2_fs.h>
-#include <gnu/fs/ext2fs/ext2_fs_sb.h>
-#include <gnu/fs/ext2fs/fs.h>
-
-#ifdef __i386__
-#include <gnu/fs/ext2fs/i386-bitops.h>
-#else
-#include <gnu/fs/ext2fs/ext2_bitops.h>
-#endif
-
-#define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
-
-/* got rid of get_group_desc since it can already be found in
- * ext2_linux_ialloc.c
- */
-
-static void read_block_bitmap (struct mount * mp,
- unsigned int block_group,
- unsigned long bitmap_nr)
-{
- struct ext2_sb_info *sb = VFSTOEXT2(mp)->um_e2fs;
- struct ext2_group_desc * gdp;
- struct buffer_head * bh;
- int error;
-
- gdp = get_group_desc (mp, block_group, NULL);
- if ((error = bread (VFSTOEXT2(mp)->um_devvp,
- fsbtodb(sb, gdp->bg_block_bitmap),sb->s_blocksize, NOCRED, &bh)) != 0)
- panic ( "read_block_bitmap: "
- "Cannot read block bitmap - "
- "block_group = %d, block_bitmap = %lu",
- block_group, (unsigned long) gdp->bg_block_bitmap);
- sb->s_block_bitmap_number[bitmap_nr] = block_group;
- sb->s_block_bitmap[bitmap_nr] = bh;
- LCK_BUF(bh)
-}
-
-/*
- * load_block_bitmap loads the block bitmap for a blocks group
- *
- * It maintains a cache for the last bitmaps loaded. This cache is managed
- * with a LRU algorithm.
- *
- * Notes:
- * 1/ There is one cache per mounted file system.
- * 2/ If the file system contains less than EXT2_MAX_GROUP_LOADED groups,
- * this function reads the bitmap without maintaining a LRU cache.
- */
-static int load__block_bitmap (struct mount * mp,
- unsigned int block_group)
-{
- int i, j;
- struct ext2_sb_info *sb = VFSTOEXT2(mp)->um_e2fs;
- unsigned long block_bitmap_number;
- struct buffer_head * block_bitmap;
-
- if (block_group >= sb->s_groups_count)
- panic ( "load_block_bitmap: "
- "block_group >= groups_count - "
- "block_group = %d, groups_count = %lu",
- block_group, sb->s_groups_count);
-
- if (sb->s_groups_count <= EXT2_MAX_GROUP_LOADED) {
- if (sb->s_block_bitmap[block_group]) {
- if (sb->s_block_bitmap_number[block_group] !=
- block_group)
- panic ( "load_block_bitmap: "
- "block_group != block_bitmap_number");
- else
- return block_group;
- } else {
- read_block_bitmap (mp, block_group, block_group);
- return block_group;
- }
- }
-
- for (i = 0; i < sb->s_loaded_block_bitmaps &&
- sb->s_block_bitmap_number[i] != block_group; i++)
- ;
- if (i < sb->s_loaded_block_bitmaps &&
- sb->s_block_bitmap_number[i] == block_group) {
- block_bitmap_number = sb->s_block_bitmap_number[i];
- block_bitmap = sb->s_block_bitmap[i];
- for (j = i; j > 0; j--) {
- sb->s_block_bitmap_number[j] =
- sb->s_block_bitmap_number[j - 1];
- sb->s_block_bitmap[j] =
- sb->s_block_bitmap[j - 1];
- }
- sb->s_block_bitmap_number[0] = block_bitmap_number;
- sb->s_block_bitmap[0] = block_bitmap;
- } else {
- if (sb->s_loaded_block_bitmaps < EXT2_MAX_GROUP_LOADED)
- sb->s_loaded_block_bitmaps++;
- else
- ULCK_BUF(sb->s_block_bitmap[EXT2_MAX_GROUP_LOADED - 1])
-
- for (j = sb->s_loaded_block_bitmaps - 1; j > 0; j--) {
- sb->s_block_bitmap_number[j] =
- sb->s_block_bitmap_number[j - 1];
- sb->s_block_bitmap[j] =
- sb->s_block_bitmap[j - 1];
- }
- read_block_bitmap (mp, block_group, 0);
- }
- return 0;
-}
-
-static __inline int load_block_bitmap (struct mount * mp,
- unsigned int block_group)
-{
- struct ext2_sb_info *sb = VFSTOEXT2(mp)->um_e2fs;
- if (sb->s_loaded_block_bitmaps > 0 &&
- sb->s_block_bitmap_number[0] == block_group)
- return 0;
-
- if (sb->s_groups_count <= EXT2_MAX_GROUP_LOADED &&
- sb->s_block_bitmap_number[block_group] == block_group &&
- sb->s_block_bitmap[block_group])
- return block_group;
-
- return load__block_bitmap (mp, block_group);
-}
-
-void ext2_free_blocks (struct mount * mp, unsigned long block,
- unsigned long count)
-{
- struct ext2_sb_info *sb = VFSTOEXT2(mp)->um_e2fs;
- struct buffer_head * bh;
- struct buffer_head * bh2;
- unsigned long block_group;
- unsigned long bit;
- unsigned long i;
- int bitmap_nr;
- struct ext2_group_desc * gdp;
- struct ext2_super_block * es;
-
- if (!sb) {
- printf ("ext2_free_blocks: nonexistent device");
- return;
- }
- es = sb->s_es;
- lock_super (VFSTOEXT2(mp)->um_devvp);
- if (block < es->s_first_data_block ||
- (block + count) > es->s_blocks_count) {
- printf ( "ext2_free_blocks: "
- "Freeing blocks not in datazone - "
- "block = %lu, count = %lu", block, count);
- unlock_super (VFSTOEXT2(mp)->um_devvp);
- return;
- }
-
- ext2_debug ("freeing blocks %lu to %lu\n", block, block+count-1);
-
- block_group = (block - es->s_first_data_block) /
- EXT2_BLOCKS_PER_GROUP(sb);
- bit = (block - es->s_first_data_block) % EXT2_BLOCKS_PER_GROUP(sb);
- if (bit + count > EXT2_BLOCKS_PER_GROUP(sb))
- panic ( "ext2_free_blocks: "
- "Freeing blocks across group boundary - "
- "Block = %lu, count = %lu",
- block, count);
- bitmap_nr = load_block_bitmap (mp, block_group);
- bh = sb->s_block_bitmap[bitmap_nr];
- gdp = get_group_desc (mp, block_group, &bh2);
-
- if (/* test_opt (sb, CHECK_STRICT) && assume always strict ! */
- (in_range (gdp->bg_block_bitmap, block, count) ||
- in_range (gdp->bg_inode_bitmap, block, count) ||
- in_range (block, gdp->bg_inode_table,
- sb->s_itb_per_group) ||
- in_range (block + count - 1, gdp->bg_inode_table,
- sb->s_itb_per_group)))
- panic ( "ext2_free_blocks: "
- "Freeing blocks in system zones - "
- "Block = %lu, count = %lu",
- block, count);
-
- for (i = 0; i < count; i++) {
- if (!clear_bit (bit + i, bh->b_data))
- printf ("ext2_free_blocks: "
- "bit already cleared for block %lu",
- block);
- else {
- gdp->bg_free_blocks_count++;
- es->s_free_blocks_count++;
- }
- }
-
- mark_buffer_dirty(bh2);
- mark_buffer_dirty(bh);
-/****
- if (sb->s_flags & MS_SYNCHRONOUS) {
- ll_rw_block (WRITE, 1, &bh);
- wait_on_buffer (bh);
- }
-****/
- sb->s_dirt = 1;
- unlock_super (VFSTOEXT2(mp)->um_devvp);
- return;
-}
-
-/*
- * ext2_new_block uses a goal block to assist allocation. If the goal is
- * free, or there is a free block within 32 blocks of the goal, that block
- * is allocated. Otherwise a forward search is made for a free block; within
- * each block group the search first looks for an entire free byte in the block
- * bitmap, and then for any free bit if that fails.
- */
-int ext2_new_block (struct mount * mp, unsigned long goal,
- u_int32_t * prealloc_count,
- u_int32_t * prealloc_block)
-{
- struct ext2_sb_info *sb = VFSTOEXT2(mp)->um_e2fs;
- struct buffer_head * bh;
- struct buffer_head * bh2;
- char * p, * r;
- int i, j, k, tmp;
- int bitmap_nr;
- struct ext2_group_desc * gdp;
- struct ext2_super_block * es;
-
-#ifdef EXT2FS_DEBUG
- static int goal_hits = 0, goal_attempts = 0;
-#endif
- if (!sb) {
- printf ("ext2_new_block: nonexistent device");
- return 0;
- }
- es = sb->s_es;
- lock_super (VFSTOEXT2(mp)->um_devvp);
-
- ext2_debug ("goal=%lu.\n", goal);
-
-repeat:
- /*
- * First, test whether the goal block is free.
- */
- if (goal < es->s_first_data_block || goal >= es->s_blocks_count)
- goal = es->s_first_data_block;
- i = (goal - es->s_first_data_block) / EXT2_BLOCKS_PER_GROUP(sb);
- gdp = get_group_desc (mp, i, &bh2);
- if (gdp->bg_free_blocks_count > 0) {
- j = ((goal - es->s_first_data_block) % EXT2_BLOCKS_PER_GROUP(sb));
-#ifdef EXT2FS_DEBUG
- if (j)
- goal_attempts++;
-#endif
- bitmap_nr = load_block_bitmap (mp, i);
- bh = sb->s_block_bitmap[bitmap_nr];
-
- ext2_debug ("goal is at %d:%d.\n", i, j);
-
- if (!test_bit(j, bh->b_data)) {
-#ifdef EXT2FS_DEBUG
- goal_hits++;
- ext2_debug ("goal bit allocated.\n");
-#endif
- goto got_block;
- }
- if (j) {
- /*
- * The goal was occupied; search forward for a free
- * block within the next XX blocks.
- *
- * end_goal is more or less random, but it has to be
- * less than EXT2_BLOCKS_PER_GROUP. Aligning up to the
- * next 64-bit boundary is simple..
- */
- int end_goal = (j + 63) & ~63;
- j = find_next_zero_bit(bh->b_data, end_goal, j);
- if (j < end_goal)
- goto got_block;
- }
-
- ext2_debug ("Bit not found near goal\n");
-
- /*
- * There has been no free block found in the near vicinity
- * of the goal: do a search forward through the block groups,
- * searching in each group first for an entire free byte in
- * the bitmap and then for any free bit.
- *
- * Search first in the remainder of the current group; then,
- * cyclicly search through the rest of the groups.
- */
- p = ((char *) bh->b_data) + (j >> 3);
- r = memscan(p, 0, (EXT2_BLOCKS_PER_GROUP(sb) - j + 7) >> 3);
- k = (r - ((char *) bh->b_data)) << 3;
- if (k < EXT2_BLOCKS_PER_GROUP(sb)) {
- j = k;
- goto search_back;
- }
- k = find_next_zero_bit ((unsigned long *) bh->b_data,
- EXT2_BLOCKS_PER_GROUP(sb),
- j);
- if (k < EXT2_BLOCKS_PER_GROUP(sb)) {
- j = k;
- goto got_block;
- }
- }
-
- ext2_debug ("Bit not found in block group %d.\n", i);
-
- /*
- * Now search the rest of the groups. We assume that
- * i and gdp correctly point to the last group visited.
- */
- for (k = 0; k < sb->s_groups_count; k++) {
- i++;
- if (i >= sb->s_groups_count)
- i = 0;
- gdp = get_group_desc (mp, i, &bh2);
- if (gdp->bg_free_blocks_count > 0)
- break;
- }
- if (k >= sb->s_groups_count) {
- unlock_super (VFSTOEXT2(mp)->um_devvp);
- return 0;
- }
- bitmap_nr = load_block_bitmap (mp, i);
- bh = sb->s_block_bitmap[bitmap_nr];
- r = memscan(bh->b_data, 0, EXT2_BLOCKS_PER_GROUP(sb) >> 3);
- j = (r - bh->b_data) << 3;
-
- if (j < EXT2_BLOCKS_PER_GROUP(sb))
- goto search_back;
- else
- j = find_first_zero_bit ((unsigned long *) bh->b_data,
- EXT2_BLOCKS_PER_GROUP(sb));
- if (j >= EXT2_BLOCKS_PER_GROUP(sb)) {
- printf ( "ext2_new_block: "
- "Free blocks count corrupted for block group %d", i);
- unlock_super (VFSTOEXT2(mp)->um_devvp);
- return 0;
- }
-
-search_back:
- /*
- * We have succeeded in finding a free byte in the block
- * bitmap. Now search backwards up to 7 bits to find the
- * start of this group of free blocks.
- */
- for (k = 0; k < 7 && j > 0 && !test_bit (j - 1, bh->b_data); k++, j--);
-
-got_block:
-
- ext2_debug ("using block group %d(%d)\n", i, gdp->bg_free_blocks_count);
-
- tmp = j + i * EXT2_BLOCKS_PER_GROUP(sb) + es->s_first_data_block;
-
- if (/* test_opt (sb, CHECK_STRICT) && we are always strict. */
- (tmp == gdp->bg_block_bitmap ||
- tmp == gdp->bg_inode_bitmap ||
- in_range (tmp, gdp->bg_inode_table, sb->s_itb_per_group)))
- panic ( "ext2_new_block: "
- "Allocating block in system zone - "
- "%dth block = %u in group %u", j, tmp, i);
-
- if (set_bit (j, bh->b_data)) {
- printf ( "ext2_new_block: "
- "bit already set for block %d", j);
- goto repeat;
- }
-
- ext2_debug ("found bit %d\n", j);
-
- /*
- * Do block preallocation now if required.
- */
-#ifdef EXT2_PREALLOCATE
- if (prealloc_block) {
- *prealloc_count = 0;
- *prealloc_block = tmp + 1;
- for (k = 1;
- k < 8 && (j + k) < EXT2_BLOCKS_PER_GROUP(sb); k++) {
- if (set_bit (j + k, bh->b_data))
- break;
- (*prealloc_count)++;
- }
- gdp->bg_free_blocks_count -= *prealloc_count;
- es->s_free_blocks_count -= *prealloc_count;
- ext2_debug ("Preallocated a further %lu bits.\n",
- *prealloc_count);
- }
-#endif
-
- j = tmp;
-
- mark_buffer_dirty(bh);
-/****
- if (sb->s_flags & MS_SYNCHRONOUS) {
- ll_rw_block (WRITE, 1, &bh);
- wait_on_buffer (bh);
- }
-****/
- if (j >= es->s_blocks_count) {
- printf ( "ext2_new_block: "
- "block >= blocks count - "
- "block_group = %d, block=%d", i, j);
- unlock_super (VFSTOEXT2(mp)->um_devvp);
- return 0;
- }
-
- ext2_debug ("allocating block %d. "
- "Goal hits %d of %d.\n", j, goal_hits, goal_attempts);
-
- gdp->bg_free_blocks_count--;
- mark_buffer_dirty(bh2);
- es->s_free_blocks_count--;
- sb->s_dirt = 1;
- unlock_super (VFSTOEXT2(mp)->um_devvp);
- return j;
-}
-
-#ifdef unused
-static unsigned long ext2_count_free_blocks (struct mount * mp)
-{
- struct ext2_sb_info *sb = VFSTOEXT2(mp)->um_e2fs;
-#ifdef EXT2FS_DEBUG
- struct ext2_super_block * es;
- unsigned long desc_count, bitmap_count, x;
- int bitmap_nr;
- struct ext2_group_desc * gdp;
- int i;
-
- lock_super (VFSTOEXT2(mp)->um_devvp);
- es = sb->s_es;
- desc_count = 0;
- bitmap_count = 0;
- gdp = NULL;
- for (i = 0; i < sb->s_groups_count; i++) {
- gdp = get_group_desc (mp, i, NULL);
- desc_count += gdp->bg_free_blocks_count;
- bitmap_nr = load_block_bitmap (mp, i);
- x = ext2_count_free (sb->s_block_bitmap[bitmap_nr],
- sb->s_blocksize);
- ext2_debug ("group %d: stored = %d, counted = %lu\n",
- i, gdp->bg_free_blocks_count, x);
- bitmap_count += x;
- }
- ext2_debug( "stored = %lu, computed = %lu, %lu\n",
- es->s_free_blocks_count, desc_count, bitmap_count);
- unlock_super (VFSTOEXT2(mp)->um_devvp);
- return bitmap_count;
-#else
- return sb->s_es->s_free_blocks_count;
-#endif
-}
-#endif /* unused */
-
-static __inline int block_in_use (unsigned long block,
- struct ext2_sb_info * sb,
- unsigned char * map)
-{
- return test_bit ((block - sb->s_es->s_first_data_block) %
- EXT2_BLOCKS_PER_GROUP(sb), map);
-}
-
-static int test_root(int a, int b)
-{
- if (a == 0)
- return 1;
- while (1) {
- if (a == 1)
- return 1;
- if (a % b)
- return 0;
- a = a / b;
- }
-}
-
-int ext2_group_sparse(int group)
-{
- return (test_root(group, 3) || test_root(group, 5) ||
- test_root(group, 7));
-}
-
-#ifdef unused
-static void ext2_check_blocks_bitmap (struct mount * mp)
-{
- struct ext2_sb_info *sb = VFSTOEXT2(mp)->um_e2fs;
- struct buffer_head * bh;
- struct ext2_super_block * es;
- unsigned long desc_count, bitmap_count, x;
- unsigned long desc_blocks;
- int bitmap_nr;
- struct ext2_group_desc * gdp;
- int i, j;
-
- lock_super (VFSTOEXT2(mp)->um_devvp);
- es = sb->s_es;
- desc_count = 0;
- bitmap_count = 0;
- gdp = NULL;
- desc_blocks = (sb->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
- EXT2_DESC_PER_BLOCK(sb);
- for (i = 0; i < sb->s_groups_count; i++) {
- gdp = get_group_desc (mp, i, NULL);
- desc_count += gdp->bg_free_blocks_count;
- bitmap_nr = load_block_bitmap (mp, i);
- bh = sb->s_block_bitmap[bitmap_nr];
-
- if (!(es->s_feature_ro_compat &
- EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER) ||
- ext2_group_sparse(i)) {
- if (!test_bit (0, bh->b_data))
- printf ("ext2_check_blocks_bitmap: "
- "Superblock in group %d "
- "is marked free", i);
-
- for (j = 0; j < desc_blocks; j++)
- if (!test_bit (j + 1, bh->b_data))
- printf ("ext2_check_blocks_bitmap: "
- "Descriptor block #%d in group "
- "%d is marked free", j, i);
- }
-
- if (!block_in_use (gdp->bg_block_bitmap, sb, bh->b_data))
- printf ("ext2_check_blocks_bitmap: "
- "Block bitmap for group %d is marked free",
- i);
-
- if (!block_in_use (gdp->bg_inode_bitmap, sb, bh->b_data))
- printf ("ext2_check_blocks_bitmap: "
- "Inode bitmap for group %d is marked free",
- i);
-
- for (j = 0; j < sb->s_itb_per_group; j++)
- if (!block_in_use (gdp->bg_inode_table + j, sb, bh->b_data))
- printf ("ext2_check_blocks_bitmap: "
- "Block #%d of the inode table in "
- "group %d is marked free", j, i);
-
- x = ext2_count_free (bh, sb->s_blocksize);
- if (gdp->bg_free_blocks_count != x)
- printf ("ext2_check_blocks_bitmap: "
- "Wrong free blocks count for group %d, "
- "stored = %d, counted = %lu", i,
- gdp->bg_free_blocks_count, x);
- bitmap_count += x;
- }
- if (es->s_free_blocks_count != bitmap_count)
- printf ("ext2_check_blocks_bitmap: "
- "Wrong free blocks count in super block, "
- "stored = %lu, counted = %lu",
- (unsigned long) es->s_free_blocks_count, bitmap_count);
- unlock_super (VFSTOEXT2(mp)->um_devvp);
-}
-#endif /* unused */
-
-/*
- * this function is taken from
- * linux/fs/ext2/bitmap.c
- */
-
-static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
-
-unsigned long ext2_count_free (struct buffer_head * map, unsigned int numchars)
-{
- unsigned int i;
- unsigned long sum = 0;
-
- if (!map)
- return (0);
- for (i = 0; i < numchars; i++)
- sum += nibblemap[map->b_data[i] & 0xf] +
- nibblemap[(map->b_data[i] >> 4) & 0xf];
- return (sum);
-}
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