#include <linux/buffer_head.h>
#include <linux/kernel.h>
#include <linux/pagemap.h>
+#include <linux/vmalloc.h>
#include <linux/reiserfs_fs_sb.h>
#include <linux/reiserfs_fs_i.h>
#include <linux/quotaops.h>
return space > 0 ? space : 0;
}
+
+void reiserfs_cache_bitmap_metadata(struct super_block *sb,
+ struct buffer_head *bh,
+ struct reiserfs_bitmap_info *info)
+{
+ unsigned long *cur = (unsigned long *)(bh->b_data + bh->b_size);
+
+ info->first_zero_hint = 1 << (sb->s_blocksize_bits + 3);
+
+ while (--cur >= (unsigned long *)bh->b_data) {
+ int base = ((char *)cur - bh->b_data) << 3;
+
+ /* 0 and ~0 are special, we can optimize for them */
+ if (*cur == 0) {
+ info->first_zero_hint = base;
+ info->free_count += BITS_PER_LONG;
+ } else if (*cur != ~0L) { /* A mix, investigate */
+ int b;
+ for (b = BITS_PER_LONG - 1; b >= 0; b--) {
+ if (!reiserfs_test_le_bit(b, cur)) {
+ info->first_zero_hint = base + b;
+ info->free_count++;
+ }
+ }
+ }
+ }
+ /* The first bit must ALWAYS be 1 */
+ BUG_ON(info->first_zero_hint == 0);
+}
+
+struct buffer_head *reiserfs_read_bitmap_block(struct super_block *sb,
+ unsigned int bitmap)
+{
+ b_blocknr_t block = (sb->s_blocksize << 3) * bitmap;
+ struct buffer_head *bh;
+
+ /* Way old format filesystems had the bitmaps packed up front.
+ * I doubt there are any of these left, but just in case... */
+ if (unlikely(test_bit(REISERFS_OLD_FORMAT,
+ &(REISERFS_SB(sb)->s_properties))))
+ block = REISERFS_SB(sb)->s_sbh->b_blocknr + 1 + bitmap;
+ else if (bitmap == 0)
+ block = (REISERFS_DISK_OFFSET_IN_BYTES >> sb->s_blocksize_bits) + 1;
+
+ bh = sb_getblk(sb, block);
+ if (!buffer_uptodate(bh))
+ ll_rw_block(READ, 1, &bh);
+
+ return bh;
+}
+
+int reiserfs_init_bitmap_cache(struct super_block *sb)
+{
+ struct reiserfs_bitmap_info *bitmap;
+ int i;
+
+ bitmap = vmalloc(sizeof (*bitmap) * SB_BMAP_NR(sb));
+ if (bitmap == NULL)
+ return -ENOMEM;
+
+ memset(bitmap, 0, sizeof (*bitmap) * SB_BMAP_NR(sb));
+
+ for (i = 0; i < SB_BMAP_NR(sb); i++)
+ bitmap[i].bh = reiserfs_read_bitmap_block(sb, i);
+
+ /* make sure we have them all */
+ for (i = 0; i < SB_BMAP_NR(sb); i++) {
+ wait_on_buffer(bitmap[i].bh);
+ if (!buffer_uptodate(bitmap[i].bh)) {
+ reiserfs_warning(sb, "sh-2029: %s: "
+ "bitmap block (#%lu) reading failed",
+ __FUNCTION__, bitmap[i].bh->b_blocknr);
+ for (i = 0; i < SB_BMAP_NR(sb); i++)
+ brelse(bitmap[i].bh);
+ vfree(bitmap);
+ return -EIO;
+ }
+ }
+
+ /* Cache the info on the bitmaps before we get rolling */
+ for (i = 0; i < SB_BMAP_NR(sb); i++)
+ reiserfs_cache_bitmap_metadata(sb, bitmap[i].bh, &bitmap[i]);
+
+ SB_AP_BITMAP(sb) = bitmap;
+
+ return 0;
+}
return 0;
}
-/* load_bitmap_info_data - Sets up the reiserfs_bitmap_info structure from disk.
- * @sb - superblock for this filesystem
- * @bi - the bitmap info to be loaded. Requires that bi->bh is valid.
- *
- * This routine counts how many free bits there are, finding the first zero
- * as a side effect. Could also be implemented as a loop of test_bit() calls, or
- * a loop of find_first_zero_bit() calls. This implementation is similar to
- * find_first_zero_bit(), but doesn't return after it finds the first bit.
- * Should only be called on fs mount, but should be fairly efficient anyways.
- *
- * bi->first_zero_hint is considered unset if it == 0, since the bitmap itself
- * will * invariably occupt block 0 represented in the bitmap. The only
- * exception to this is when free_count also == 0, since there will be no
- * free blocks at all.
- */
-
-static void load_bitmap_info_data(struct super_block *sb,
- struct reiserfs_bitmap_info *bi)
-{
- unsigned long *cur = (unsigned long *)bi->bh->b_data;
-
- while ((char *)cur < (bi->bh->b_data + sb->s_blocksize)) {
-
- /* No need to scan if all 0's or all 1's.
- * Since we're only counting 0's, we can simply ignore all 1's */
- if (*cur == 0) {
- if (bi->first_zero_hint == 0) {
- bi->first_zero_hint =
- ((char *)cur - bi->bh->b_data) << 3;
- }
- bi->free_count += sizeof(unsigned long) * 8;
- } else if (*cur != ~0L) {
- int b;
- for (b = 0; b < sizeof(unsigned long) * 8; b++) {
- if (!reiserfs_test_le_bit(b, cur)) {
- bi->free_count++;
- if (bi->first_zero_hint == 0)
- bi->first_zero_hint =
- (((char *)cur -
- bi->bh->b_data) << 3) + b;
- }
- }
- }
- cur++;
- }
-
-#ifdef CONFIG_REISERFS_CHECK
-// This outputs a lot of unneded info on big FSes
-// reiserfs_warning ("bitmap loaded from block %d: %d free blocks",
-// bi->bh->b_blocknr, bi->free_count);
-#endif
-}
-
-static int read_bitmaps(struct super_block *s)
-{
- int i, bmap_nr;
-
- SB_AP_BITMAP(s) =
- vmalloc(sizeof(struct reiserfs_bitmap_info) * SB_BMAP_NR(s));
- if (SB_AP_BITMAP(s) == 0)
- return 1;
- memset(SB_AP_BITMAP(s), 0,
- sizeof(struct reiserfs_bitmap_info) * SB_BMAP_NR(s));
- for (i = 0, bmap_nr =
- REISERFS_DISK_OFFSET_IN_BYTES / s->s_blocksize + 1;
- i < SB_BMAP_NR(s); i++, bmap_nr = s->s_blocksize * 8 * i) {
- SB_AP_BITMAP(s)[i].bh = sb_getblk(s, bmap_nr);
- if (!buffer_uptodate(SB_AP_BITMAP(s)[i].bh))
- ll_rw_block(READ, 1, &SB_AP_BITMAP(s)[i].bh);
- }
- for (i = 0; i < SB_BMAP_NR(s); i++) {
- wait_on_buffer(SB_AP_BITMAP(s)[i].bh);
- if (!buffer_uptodate(SB_AP_BITMAP(s)[i].bh)) {
- reiserfs_warning(s, "sh-2029: reiserfs read_bitmaps: "
- "bitmap block (#%lu) reading failed",
- SB_AP_BITMAP(s)[i].bh->b_blocknr);
- for (i = 0; i < SB_BMAP_NR(s); i++)
- brelse(SB_AP_BITMAP(s)[i].bh);
- vfree(SB_AP_BITMAP(s));
- SB_AP_BITMAP(s) = NULL;
- return 1;
- }
- load_bitmap_info_data(s, SB_AP_BITMAP(s) + i);
- }
- return 0;
-}
-
-static int read_old_bitmaps(struct super_block *s)
-{
- int i;
- struct reiserfs_super_block *rs = SB_DISK_SUPER_BLOCK(s);
- int bmp1 = (REISERFS_OLD_DISK_OFFSET_IN_BYTES / s->s_blocksize) + 1; /* first of bitmap blocks */
-
- /* read true bitmap */
- SB_AP_BITMAP(s) =
- vmalloc(sizeof(struct reiserfs_buffer_info *) * sb_bmap_nr(rs));
- if (SB_AP_BITMAP(s) == 0)
- return 1;
-
- memset(SB_AP_BITMAP(s), 0,
- sizeof(struct reiserfs_buffer_info *) * sb_bmap_nr(rs));
-
- for (i = 0; i < sb_bmap_nr(rs); i++) {
- SB_AP_BITMAP(s)[i].bh = sb_bread(s, bmp1 + i);
- if (!SB_AP_BITMAP(s)[i].bh)
- return 1;
- load_bitmap_info_data(s, SB_AP_BITMAP(s) + i);
- }
-
- return 0;
-}
-
static int read_super_block(struct super_block *s, int offset)
{
struct buffer_head *bh;
sbi->s_mount_state = SB_REISERFS_STATE(s);
sbi->s_mount_state = REISERFS_VALID_FS;
- if (old_format ? read_old_bitmaps(s) : read_bitmaps(s)) {
+ if ((errval = reiserfs_init_bitmap_cache(s))) {
SWARN(silent, s,
"jmacd-8: reiserfs_fill_super: unable to read bitmap");
goto error;
projects / kernel.git / commitdiff