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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/udf/balloc.c
Initial import
Diffstat (limited to 'fs/udf/balloc.c')
-rw-r--r--fs/udf/balloc.c821
1 files changed, 821 insertions, 0 deletions
diff --git a/fs/udf/balloc.c b/fs/udf/balloc.c
new file mode 100644
index 000000000..6d6a96b4e
--- /dev/null
+++ b/fs/udf/balloc.c
@@ -0,0 +1,821 @@
+/*
+ * balloc.c
+ *
+ * PURPOSE
+ * Block allocation handling routines for the OSTA-UDF(tm) filesystem.
+ *
+ * COPYRIGHT
+ * This file is distributed under the terms of the GNU General Public
+ * License (GPL). Copies of the GPL can be obtained from:
+ * ftp://prep.ai.mit.edu/pub/gnu/GPL
+ * Each contributing author retains all rights to their own work.
+ *
+ * (C) 1999-2001 Ben Fennema
+ * (C) 1999 Stelias Computing Inc
+ *
+ * HISTORY
+ *
+ * 02/24/99 blf Created.
+ *
+ */
+
+#include "udfdecl.h"
+
+#include <linux/bitops.h>
+
+#include "udf_i.h"
+#include "udf_sb.h"
+
+#define udf_clear_bit __test_and_clear_bit_le
+#define udf_set_bit __test_and_set_bit_le
+#define udf_test_bit test_bit_le
+#define udf_find_next_one_bit find_next_bit_le
+
+static int read_block_bitmap(struct super_block *sb,
+ struct udf_bitmap *bitmap, unsigned int block,
+ unsigned long bitmap_nr)
+{
+ struct buffer_head *bh = NULL;
+ int retval = 0;
+ struct kernel_lb_addr loc;
+
+ loc.logicalBlockNum = bitmap->s_extPosition;
+ loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
+
+ bh = udf_tread(sb, udf_get_lb_pblock(sb, &loc, block));
+ if (!bh)
+ retval = -EIO;
+
+ bitmap->s_block_bitmap[bitmap_nr] = bh;
+ return retval;
+}
+
+static int __load_block_bitmap(struct super_block *sb,
+ struct udf_bitmap *bitmap,
+ unsigned int block_group)
+{
+ int retval = 0;
+ int nr_groups = bitmap->s_nr_groups;
+
+ if (block_group >= nr_groups) {
+ udf_debug("block_group (%d) > nr_groups (%d)\n",
+ block_group, nr_groups);
+ }
+
+ if (bitmap->s_block_bitmap[block_group])
+ return block_group;
+
+ retval = read_block_bitmap(sb, bitmap, block_group, block_group);
+ if (retval < 0)
+ return retval;
+
+ return block_group;
+}
+
+static inline int load_block_bitmap(struct super_block *sb,
+ struct udf_bitmap *bitmap,
+ unsigned int block_group)
+{
+ int slot;
+
+ slot = __load_block_bitmap(sb, bitmap, block_group);
+
+ if (slot < 0)
+ return slot;
+
+ if (!bitmap->s_block_bitmap[slot])
+ return -EIO;
+
+ return slot;
+}
+
+static void udf_add_free_space(struct super_block *sb, u16 partition, u32 cnt)
+{
+ struct udf_sb_info *sbi = UDF_SB(sb);
+ struct logicalVolIntegrityDesc *lvid;
+
+ if (!sbi->s_lvid_bh)
+ return;
+
+ lvid = (struct logicalVolIntegrityDesc *)sbi->s_lvid_bh->b_data;
+ le32_add_cpu(&lvid->freeSpaceTable[partition], cnt);
+ udf_updated_lvid(sb);
+}
+
+static void udf_bitmap_free_blocks(struct super_block *sb,
+ struct udf_bitmap *bitmap,
+ struct kernel_lb_addr *bloc,
+ uint32_t offset,
+ uint32_t count)
+{
+ struct udf_sb_info *sbi = UDF_SB(sb);
+ struct buffer_head *bh = NULL;
+ struct udf_part_map *partmap;
+ unsigned long block;
+ unsigned long block_group;
+ unsigned long bit;
+ unsigned long i;
+ int bitmap_nr;
+ unsigned long overflow;
+
+ mutex_lock(&sbi->s_alloc_mutex);
+ partmap = &sbi->s_partmaps[bloc->partitionReferenceNum];
+ if (bloc->logicalBlockNum + count < count ||
+ (bloc->logicalBlockNum + count) > partmap->s_partition_len) {
+ udf_debug("%d < %d || %d + %d > %d\n",
+ bloc->logicalBlockNum, 0,
+ bloc->logicalBlockNum, count,
+ partmap->s_partition_len);
+ goto error_return;
+ }
+
+ block = bloc->logicalBlockNum + offset +
+ (sizeof(struct spaceBitmapDesc) << 3);
+
+ do {
+ overflow = 0;
+ block_group = block >> (sb->s_blocksize_bits + 3);
+ bit = block % (sb->s_blocksize << 3);
+
+ /*
+ * Check to see if we are freeing blocks across a group boundary.
+ */
+ if (bit + count > (sb->s_blocksize << 3)) {
+ overflow = bit + count - (sb->s_blocksize << 3);
+ count -= overflow;
+ }
+ bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
+ if (bitmap_nr < 0)
+ goto error_return;
+
+ bh = bitmap->s_block_bitmap[bitmap_nr];
+ for (i = 0; i < count; i++) {
+ if (udf_set_bit(bit + i, bh->b_data)) {
+ udf_debug("bit %ld already set\n", bit + i);
+ udf_debug("byte=%2x\n",
+ ((char *)bh->b_data)[(bit + i) >> 3]);
+ }
+ }
+ udf_add_free_space(sb, sbi->s_partition, count);
+ mark_buffer_dirty(bh);
+ if (overflow) {
+ block += count;
+ count = overflow;
+ }
+ } while (overflow);
+
+error_return:
+ mutex_unlock(&sbi->s_alloc_mutex);
+}
+
+static int udf_bitmap_prealloc_blocks(struct super_block *sb,
+ struct udf_bitmap *bitmap,
+ uint16_t partition, uint32_t first_block,
+ uint32_t block_count)
+{
+ struct udf_sb_info *sbi = UDF_SB(sb);
+ int alloc_count = 0;
+ int bit, block, block_group, group_start;
+ int nr_groups, bitmap_nr;
+ struct buffer_head *bh;
+ __u32 part_len;
+
+ mutex_lock(&sbi->s_alloc_mutex);
+ part_len = sbi->s_partmaps[partition].s_partition_len;
+ if (first_block >= part_len)
+ goto out;
+
+ if (first_block + block_count > part_len)
+ block_count = part_len - first_block;
+
+ do {
+ nr_groups = udf_compute_nr_groups(sb, partition);
+ block = first_block + (sizeof(struct spaceBitmapDesc) << 3);
+ block_group = block >> (sb->s_blocksize_bits + 3);
+ group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
+
+ bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
+ if (bitmap_nr < 0)
+ goto out;
+ bh = bitmap->s_block_bitmap[bitmap_nr];
+
+ bit = block % (sb->s_blocksize << 3);
+
+ while (bit < (sb->s_blocksize << 3) && block_count > 0) {
+ if (!udf_clear_bit(bit, bh->b_data))
+ goto out;
+ block_count--;
+ alloc_count++;
+ bit++;
+ block++;
+ }
+ mark_buffer_dirty(bh);
+ } while (block_count > 0);
+
+out:
+ udf_add_free_space(sb, partition, -alloc_count);
+ mutex_unlock(&sbi->s_alloc_mutex);
+ return alloc_count;
+}
+
+static int udf_bitmap_new_block(struct super_block *sb,
+ struct udf_bitmap *bitmap, uint16_t partition,
+ uint32_t goal, int *err)
+{
+ struct udf_sb_info *sbi = UDF_SB(sb);
+ int newbit, bit = 0, block, block_group, group_start;
+ int end_goal, nr_groups, bitmap_nr, i;
+ struct buffer_head *bh = NULL;
+ char *ptr;
+ int newblock = 0;
+
+ *err = -ENOSPC;
+ mutex_lock(&sbi->s_alloc_mutex);
+
+repeat:
+ if (goal >= sbi->s_partmaps[partition].s_partition_len)
+ goal = 0;
+
+ nr_groups = bitmap->s_nr_groups;
+ block = goal + (sizeof(struct spaceBitmapDesc) << 3);
+ block_group = block >> (sb->s_blocksize_bits + 3);
+ group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
+
+ bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
+ if (bitmap_nr < 0)
+ goto error_return;
+ bh = bitmap->s_block_bitmap[bitmap_nr];
+ ptr = memscan((char *)bh->b_data + group_start, 0xFF,
+ sb->s_blocksize - group_start);
+
+ if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) {
+ bit = block % (sb->s_blocksize << 3);
+ if (udf_test_bit(bit, bh->b_data))
+ goto got_block;
+
+ end_goal = (bit + 63) & ~63;
+ bit = udf_find_next_one_bit(bh->b_data, end_goal, bit);
+ if (bit < end_goal)
+ goto got_block;
+
+ ptr = memscan((char *)bh->b_data + (bit >> 3), 0xFF,
+ sb->s_blocksize - ((bit + 7) >> 3));
+ newbit = (ptr - ((char *)bh->b_data)) << 3;
+ if (newbit < sb->s_blocksize << 3) {
+ bit = newbit;
+ goto search_back;
+ }
+
+ newbit = udf_find_next_one_bit(bh->b_data,
+ sb->s_blocksize << 3, bit);
+ if (newbit < sb->s_blocksize << 3) {
+ bit = newbit;
+ goto got_block;
+ }
+ }
+
+ for (i = 0; i < (nr_groups * 2); i++) {
+ block_group++;
+ if (block_group >= nr_groups)
+ block_group = 0;
+ group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
+
+ bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
+ if (bitmap_nr < 0)
+ goto error_return;
+ bh = bitmap->s_block_bitmap[bitmap_nr];
+ if (i < nr_groups) {
+ ptr = memscan((char *)bh->b_data + group_start, 0xFF,
+ sb->s_blocksize - group_start);
+ if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) {
+ bit = (ptr - ((char *)bh->b_data)) << 3;
+ break;
+ }
+ } else {
+ bit = udf_find_next_one_bit(bh->b_data,
+ sb->s_blocksize << 3,
+ group_start << 3);
+ if (bit < sb->s_blocksize << 3)
+ break;
+ }
+ }
+ if (i >= (nr_groups * 2)) {
+ mutex_unlock(&sbi->s_alloc_mutex);
+ return newblock;
+ }
+ if (bit < sb->s_blocksize << 3)
+ goto search_back;
+ else
+ bit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3,
+ group_start << 3);
+ if (bit >= sb->s_blocksize << 3) {
+ mutex_unlock(&sbi->s_alloc_mutex);
+ return 0;
+ }
+
+search_back:
+ i = 0;
+ while (i < 7 && bit > (group_start << 3) &&
+ udf_test_bit(bit - 1, bh->b_data)) {
+ ++i;
+ --bit;
+ }
+
+got_block:
+ newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) -
+ (sizeof(struct spaceBitmapDesc) << 3);
+
+ if (!udf_clear_bit(bit, bh->b_data)) {
+ udf_debug("bit already cleared for block %d\n", bit);
+ goto repeat;
+ }
+
+ mark_buffer_dirty(bh);
+
+ udf_add_free_space(sb, partition, -1);
+ mutex_unlock(&sbi->s_alloc_mutex);
+ *err = 0;
+ return newblock;
+
+error_return:
+ *err = -EIO;
+ mutex_unlock(&sbi->s_alloc_mutex);
+ return 0;
+}
+
+static void udf_table_free_blocks(struct super_block *sb,
+ struct inode *table,
+ struct kernel_lb_addr *bloc,
+ uint32_t offset,
+ uint32_t count)
+{
+ struct udf_sb_info *sbi = UDF_SB(sb);
+ struct udf_part_map *partmap;
+ uint32_t start, end;
+ uint32_t elen;
+ struct kernel_lb_addr eloc;
+ struct extent_position oepos, epos;
+ int8_t etype;
+ struct udf_inode_info *iinfo;
+
+ mutex_lock(&sbi->s_alloc_mutex);
+ partmap = &sbi->s_partmaps[bloc->partitionReferenceNum];
+ if (bloc->logicalBlockNum + count < count ||
+ (bloc->logicalBlockNum + count) > partmap->s_partition_len) {
+ udf_debug("%d < %d || %d + %d > %d\n",
+ bloc->logicalBlockNum, 0,
+ bloc->logicalBlockNum, count,
+ partmap->s_partition_len);
+ goto error_return;
+ }
+
+ iinfo = UDF_I(table);
+ udf_add_free_space(sb, sbi->s_partition, count);
+
+ start = bloc->logicalBlockNum + offset;
+ end = bloc->logicalBlockNum + offset + count - 1;
+
+ epos.offset = oepos.offset = sizeof(struct unallocSpaceEntry);
+ elen = 0;
+ epos.block = oepos.block = iinfo->i_location;
+ epos.bh = oepos.bh = NULL;
+
+ while (count &&
+ (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
+ if (((eloc.logicalBlockNum +
+ (elen >> sb->s_blocksize_bits)) == start)) {
+ if ((0x3FFFFFFF - elen) <
+ (count << sb->s_blocksize_bits)) {
+ uint32_t tmp = ((0x3FFFFFFF - elen) >>
+ sb->s_blocksize_bits);
+ count -= tmp;
+ start += tmp;
+ elen = (etype << 30) |
+ (0x40000000 - sb->s_blocksize);
+ } else {
+ elen = (etype << 30) |
+ (elen +
+ (count << sb->s_blocksize_bits));
+ start += count;
+ count = 0;
+ }
+ udf_write_aext(table, &oepos, &eloc, elen, 1);
+ } else if (eloc.logicalBlockNum == (end + 1)) {
+ if ((0x3FFFFFFF - elen) <
+ (count << sb->s_blocksize_bits)) {
+ uint32_t tmp = ((0x3FFFFFFF - elen) >>
+ sb->s_blocksize_bits);
+ count -= tmp;
+ end -= tmp;
+ eloc.logicalBlockNum -= tmp;
+ elen = (etype << 30) |
+ (0x40000000 - sb->s_blocksize);
+ } else {
+ eloc.logicalBlockNum = start;
+ elen = (etype << 30) |
+ (elen +
+ (count << sb->s_blocksize_bits));
+ end -= count;
+ count = 0;
+ }
+ udf_write_aext(table, &oepos, &eloc, elen, 1);
+ }
+
+ if (epos.bh != oepos.bh) {
+ oepos.block = epos.block;
+ brelse(oepos.bh);
+ get_bh(epos.bh);
+ oepos.bh = epos.bh;
+ oepos.offset = 0;
+ } else {
+ oepos.offset = epos.offset;
+ }
+ }
+
+ if (count) {
+ /*
+ * NOTE: we CANNOT use udf_add_aext here, as it can try to
+ * allocate a new block, and since we hold the super block
+ * lock already very bad things would happen :)
+ *
+ * We copy the behavior of udf_add_aext, but instead of
+ * trying to allocate a new block close to the existing one,
+ * we just steal a block from the extent we are trying to add.
+ *
+ * It would be nice if the blocks were close together, but it
+ * isn't required.
+ */
+
+ int adsize;
+ struct short_ad *sad = NULL;
+ struct long_ad *lad = NULL;
+ struct allocExtDesc *aed;
+
+ eloc.logicalBlockNum = start;
+ elen = EXT_RECORDED_ALLOCATED |
+ (count << sb->s_blocksize_bits);
+
+ if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
+ adsize = sizeof(struct short_ad);
+ else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
+ adsize = sizeof(struct long_ad);
+ else {
+ brelse(oepos.bh);
+ brelse(epos.bh);
+ goto error_return;
+ }
+
+ if (epos.offset + (2 * adsize) > sb->s_blocksize) {
+ unsigned char *sptr, *dptr;
+ int loffset;
+
+ brelse(oepos.bh);
+ oepos = epos;
+
+ /* Steal a block from the extent being free'd */
+ epos.block.logicalBlockNum = eloc.logicalBlockNum;
+ eloc.logicalBlockNum++;
+ elen -= sb->s_blocksize;
+
+ epos.bh = udf_tread(sb,
+ udf_get_lb_pblock(sb, &epos.block, 0));
+ if (!epos.bh) {
+ brelse(oepos.bh);
+ goto error_return;
+ }
+ aed = (struct allocExtDesc *)(epos.bh->b_data);
+ aed->previousAllocExtLocation =
+ cpu_to_le32(oepos.block.logicalBlockNum);
+ if (epos.offset + adsize > sb->s_blocksize) {
+ loffset = epos.offset;
+ aed->lengthAllocDescs = cpu_to_le32(adsize);
+ sptr = iinfo->i_ext.i_data + epos.offset
+ - adsize;
+ dptr = epos.bh->b_data +
+ sizeof(struct allocExtDesc);
+ memcpy(dptr, sptr, adsize);
+ epos.offset = sizeof(struct allocExtDesc) +
+ adsize;
+ } else {
+ loffset = epos.offset + adsize;
+ aed->lengthAllocDescs = cpu_to_le32(0);
+ if (oepos.bh) {
+ sptr = oepos.bh->b_data + epos.offset;
+ aed = (struct allocExtDesc *)
+ oepos.bh->b_data;
+ le32_add_cpu(&aed->lengthAllocDescs,
+ adsize);
+ } else {
+ sptr = iinfo->i_ext.i_data +
+ epos.offset;
+ iinfo->i_lenAlloc += adsize;
+ mark_inode_dirty(table);
+ }
+ epos.offset = sizeof(struct allocExtDesc);
+ }
+ if (sbi->s_udfrev >= 0x0200)
+ udf_new_tag(epos.bh->b_data, TAG_IDENT_AED,
+ 3, 1, epos.block.logicalBlockNum,
+ sizeof(struct tag));
+ else
+ udf_new_tag(epos.bh->b_data, TAG_IDENT_AED,
+ 2, 1, epos.block.logicalBlockNum,
+ sizeof(struct tag));
+
+ switch (iinfo->i_alloc_type) {
+ case ICBTAG_FLAG_AD_SHORT:
+ sad = (struct short_ad *)sptr;
+ sad->extLength = cpu_to_le32(
+ EXT_NEXT_EXTENT_ALLOCDECS |
+ sb->s_blocksize);
+ sad->extPosition =
+ cpu_to_le32(epos.block.logicalBlockNum);
+ break;
+ case ICBTAG_FLAG_AD_LONG:
+ lad = (struct long_ad *)sptr;
+ lad->extLength = cpu_to_le32(
+ EXT_NEXT_EXTENT_ALLOCDECS |
+ sb->s_blocksize);
+ lad->extLocation =
+ cpu_to_lelb(epos.block);
+ break;
+ }
+ if (oepos.bh) {
+ udf_update_tag(oepos.bh->b_data, loffset);
+ mark_buffer_dirty(oepos.bh);
+ } else {
+ mark_inode_dirty(table);
+ }
+ }
+
+ /* It's possible that stealing the block emptied the extent */
+ if (elen) {
+ udf_write_aext(table, &epos, &eloc, elen, 1);
+
+ if (!epos.bh) {
+ iinfo->i_lenAlloc += adsize;
+ mark_inode_dirty(table);
+ } else {
+ aed = (struct allocExtDesc *)epos.bh->b_data;
+ le32_add_cpu(&aed->lengthAllocDescs, adsize);
+ udf_update_tag(epos.bh->b_data, epos.offset);
+ mark_buffer_dirty(epos.bh);
+ }
+ }
+ }
+
+ brelse(epos.bh);
+ brelse(oepos.bh);
+
+error_return:
+ mutex_unlock(&sbi->s_alloc_mutex);
+ return;
+}
+
+static int udf_table_prealloc_blocks(struct super_block *sb,
+ struct inode *table, uint16_t partition,
+ uint32_t first_block, uint32_t block_count)
+{
+ struct udf_sb_info *sbi = UDF_SB(sb);
+ int alloc_count = 0;
+ uint32_t elen, adsize;
+ struct kernel_lb_addr eloc;
+ struct extent_position epos;
+ int8_t etype = -1;
+ struct udf_inode_info *iinfo;
+
+ if (first_block >= sbi->s_partmaps[partition].s_partition_len)
+ return 0;
+
+ iinfo = UDF_I(table);
+ if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
+ adsize = sizeof(struct short_ad);
+ else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
+ adsize = sizeof(struct long_ad);
+ else
+ return 0;
+
+ mutex_lock(&sbi->s_alloc_mutex);
+ epos.offset = sizeof(struct unallocSpaceEntry);
+ epos.block = iinfo->i_location;
+ epos.bh = NULL;
+ eloc.logicalBlockNum = 0xFFFFFFFF;
+
+ while (first_block != eloc.logicalBlockNum &&
+ (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
+ udf_debug("eloc=%d, elen=%d, first_block=%d\n",
+ eloc.logicalBlockNum, elen, first_block);
+ ; /* empty loop body */
+ }
+
+ if (first_block == eloc.logicalBlockNum) {
+ epos.offset -= adsize;
+
+ alloc_count = (elen >> sb->s_blocksize_bits);
+ if (alloc_count > block_count) {
+ alloc_count = block_count;
+ eloc.logicalBlockNum += alloc_count;
+ elen -= (alloc_count << sb->s_blocksize_bits);
+ udf_write_aext(table, &epos, &eloc,
+ (etype << 30) | elen, 1);
+ } else
+ udf_delete_aext(table, epos, eloc,
+ (etype << 30) | elen);
+ } else {
+ alloc_count = 0;
+ }
+
+ brelse(epos.bh);
+
+ if (alloc_count)
+ udf_add_free_space(sb, partition, -alloc_count);
+ mutex_unlock(&sbi->s_alloc_mutex);
+ return alloc_count;
+}
+
+static int udf_table_new_block(struct super_block *sb,
+ struct inode *table, uint16_t partition,
+ uint32_t goal, int *err)
+{
+ struct udf_sb_info *sbi = UDF_SB(sb);
+ uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF;
+ uint32_t newblock = 0, adsize;
+ uint32_t elen, goal_elen = 0;
+ struct kernel_lb_addr eloc, uninitialized_var(goal_eloc);
+ struct extent_position epos, goal_epos;
+ int8_t etype;
+ struct udf_inode_info *iinfo = UDF_I(table);
+
+ *err = -ENOSPC;
+
+ if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
+ adsize = sizeof(struct short_ad);
+ else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
+ adsize = sizeof(struct long_ad);
+ else
+ return newblock;
+
+ mutex_lock(&sbi->s_alloc_mutex);
+ if (goal >= sbi->s_partmaps[partition].s_partition_len)
+ goal = 0;
+
+ /* We search for the closest matching block to goal. If we find
+ a exact hit, we stop. Otherwise we keep going till we run out
+ of extents. We store the buffer_head, bloc, and extoffset
+ of the current closest match and use that when we are done.
+ */
+ epos.offset = sizeof(struct unallocSpaceEntry);
+ epos.block = iinfo->i_location;
+ epos.bh = goal_epos.bh = NULL;
+
+ while (spread &&
+ (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
+ if (goal >= eloc.logicalBlockNum) {
+ if (goal < eloc.logicalBlockNum +
+ (elen >> sb->s_blocksize_bits))
+ nspread = 0;
+ else
+ nspread = goal - eloc.logicalBlockNum -
+ (elen >> sb->s_blocksize_bits);
+ } else {
+ nspread = eloc.logicalBlockNum - goal;
+ }
+
+ if (nspread < spread) {
+ spread = nspread;
+ if (goal_epos.bh != epos.bh) {
+ brelse(goal_epos.bh);
+ goal_epos.bh = epos.bh;
+ get_bh(goal_epos.bh);
+ }
+ goal_epos.block = epos.block;
+ goal_epos.offset = epos.offset - adsize;
+ goal_eloc = eloc;
+ goal_elen = (etype << 30) | elen;
+ }
+ }
+
+ brelse(epos.bh);
+
+ if (spread == 0xFFFFFFFF) {
+ brelse(goal_epos.bh);
+ mutex_unlock(&sbi->s_alloc_mutex);
+ return 0;
+ }
+
+ /* Only allocate blocks from the beginning of the extent.
+ That way, we only delete (empty) extents, never have to insert an
+ extent because of splitting */
+ /* This works, but very poorly.... */
+
+ newblock = goal_eloc.logicalBlockNum;
+ goal_eloc.logicalBlockNum++;
+ goal_elen -= sb->s_blocksize;
+
+ if (goal_elen)
+ udf_write_aext(table, &goal_epos, &goal_eloc, goal_elen, 1);
+ else
+ udf_delete_aext(table, goal_epos, goal_eloc, goal_elen);
+ brelse(goal_epos.bh);
+
+ udf_add_free_space(sb, partition, -1);
+
+ mutex_unlock(&sbi->s_alloc_mutex);
+ *err = 0;
+ return newblock;
+}
+
+void udf_free_blocks(struct super_block *sb, struct inode *inode,
+ struct kernel_lb_addr *bloc, uint32_t offset,
+ uint32_t count)
+{
+ uint16_t partition = bloc->partitionReferenceNum;
+ struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
+
+ if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
+ udf_bitmap_free_blocks(sb, map->s_uspace.s_bitmap,
+ bloc, offset, count);
+ } else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
+ udf_table_free_blocks(sb, map->s_uspace.s_table,
+ bloc, offset, count);
+ } else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) {
+ udf_bitmap_free_blocks(sb, map->s_fspace.s_bitmap,
+ bloc, offset, count);
+ } else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) {
+ udf_table_free_blocks(sb, map->s_fspace.s_table,
+ bloc, offset, count);
+ }
+
+ if (inode) {
+ inode_sub_bytes(inode,
+ ((sector_t)count) << sb->s_blocksize_bits);
+ }
+}
+
+inline int udf_prealloc_blocks(struct super_block *sb,
+ struct inode *inode,
+ uint16_t partition, uint32_t first_block,
+ uint32_t block_count)
+{
+ struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
+ int allocated;
+
+ if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
+ allocated = udf_bitmap_prealloc_blocks(sb,
+ map->s_uspace.s_bitmap,
+ partition, first_block,
+ block_count);
+ else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
+ allocated = udf_table_prealloc_blocks(sb,
+ map->s_uspace.s_table,
+ partition, first_block,
+ block_count);
+ else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP)
+ allocated = udf_bitmap_prealloc_blocks(sb,
+ map->s_fspace.s_bitmap,
+ partition, first_block,
+ block_count);
+ else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE)
+ allocated = udf_table_prealloc_blocks(sb,
+ map->s_fspace.s_table,
+ partition, first_block,
+ block_count);
+ else
+ return 0;
+
+ if (inode && allocated > 0)
+ inode_add_bytes(inode, allocated << sb->s_blocksize_bits);
+ return allocated;
+}
+
+inline int udf_new_block(struct super_block *sb,
+ struct inode *inode,
+ uint16_t partition, uint32_t goal, int *err)
+{
+ struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
+ int block;
+
+ if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
+ block = udf_bitmap_new_block(sb,
+ map->s_uspace.s_bitmap,
+ partition, goal, err);
+ else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
+ block = udf_table_new_block(sb,
+ map->s_uspace.s_table,
+ partition, goal, err);
+ else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP)
+ block = udf_bitmap_new_block(sb,
+ map->s_fspace.s_bitmap,
+ partition, goal, err);
+ else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE)
+ block = udf_table_new_block(sb,
+ map->s_fspace.s_table,
+ partition, goal, err);
+ else {
+ *err = -EIO;
+ return 0;
+ }
+ if (inode && block)
+ inode_add_bytes(inode, sb->s_blocksize);
+ return block;
+}