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-rw-r--r--fs/exfat/balloc.c236
1 files changed, 148 insertions, 88 deletions
diff --git a/fs/exfat/balloc.c b/fs/exfat/balloc.c
index 03f142307174..5429041c7eaf 100644
--- a/fs/exfat/balloc.c
+++ b/fs/exfat/balloc.c
@@ -5,53 +5,80 @@
#include <linux/blkdev.h>
#include <linux/slab.h>
+#include <linux/bitmap.h>
#include <linux/buffer_head.h>
+#include <linux/backing-dev.h>
#include "exfat_raw.h"
#include "exfat_fs.h"
-static const unsigned char free_bit[] = {
- 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2,/* 0 ~ 19*/
- 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 5, 0, 1, 0, 2, 0, 1, 0, 3,/* 20 ~ 39*/
- 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2,/* 40 ~ 59*/
- 0, 1, 0, 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4,/* 60 ~ 79*/
- 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 5, 0, 1, 0, 2,/* 80 ~ 99*/
- 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3,/*100 ~ 119*/
- 0, 1, 0, 2, 0, 1, 0, 7, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2,/*120 ~ 139*/
- 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 5,/*140 ~ 159*/
- 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2,/*160 ~ 179*/
- 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 6, 0, 1, 0, 2, 0, 1, 0, 3,/*180 ~ 199*/
- 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2,/*200 ~ 219*/
- 0, 1, 0, 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4,/*220 ~ 239*/
- 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0 /*240 ~ 254*/
-};
-
-static const unsigned char used_bit[] = {
- 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4, 1, 2, 2, 3,/* 0 ~ 19*/
- 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 1, 2, 2, 3, 2, 3, 3, 4,/* 20 ~ 39*/
- 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5,/* 40 ~ 59*/
- 4, 5, 5, 6, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,/* 60 ~ 79*/
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 2, 3, 3, 4,/* 80 ~ 99*/
- 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6,/*100 ~ 119*/
- 4, 5, 5, 6, 5, 6, 6, 7, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4,/*120 ~ 139*/
- 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,/*140 ~ 159*/
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5,/*160 ~ 179*/
- 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 2, 3, 3, 4, 3, 4, 4, 5,/*180 ~ 199*/
- 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6,/*200 ~ 219*/
- 5, 6, 6, 7, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,/*220 ~ 239*/
- 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8 /*240 ~ 255*/
-};
+#if BITS_PER_LONG == 32
+#define __le_long __le32
+#define lel_to_cpu(A) le32_to_cpu(A)
+#define cpu_to_lel(A) cpu_to_le32(A)
+#elif BITS_PER_LONG == 64
+#define __le_long __le64
+#define lel_to_cpu(A) le64_to_cpu(A)
+#define cpu_to_lel(A) cpu_to_le64(A)
+#else
+#error "BITS_PER_LONG not 32 or 64"
+#endif
/*
* Allocation Bitmap Management Functions
*/
+static bool exfat_test_bitmap_range(struct super_block *sb, unsigned int clu,
+ unsigned int count)
+{
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ unsigned int start = clu;
+ unsigned int end = clu + count;
+ unsigned int ent_idx, i, b;
+ unsigned int bit_offset, bits_to_check;
+ __le_long *bitmap_le;
+ unsigned long mask, word;
+
+ if (!is_valid_cluster(sbi, start) || !is_valid_cluster(sbi, end - 1))
+ return false;
+
+ while (start < end) {
+ ent_idx = CLUSTER_TO_BITMAP_ENT(start);
+ i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx);
+ b = BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent_idx);
+
+ bitmap_le = (__le_long *)sbi->vol_amap[i]->b_data;
+
+ /* Calculate how many bits we can check in the current word */
+ bit_offset = b % BITS_PER_LONG;
+ bits_to_check = min(end - start,
+ (unsigned int)(BITS_PER_LONG - bit_offset));
+
+ /* Create a bitmask for the range of bits to check */
+ if (bits_to_check >= BITS_PER_LONG)
+ mask = ~0UL;
+ else
+ mask = ((1UL << bits_to_check) - 1) << bit_offset;
+ word = lel_to_cpu(bitmap_le[b / BITS_PER_LONG]);
+
+ /* Check if all bits in the mask are set */
+ if ((word & mask) != mask)
+ return false;
+
+ start += bits_to_check;
+ }
+
+ return true;
+}
+
static int exfat_allocate_bitmap(struct super_block *sb,
struct exfat_dentry *ep)
{
struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ struct blk_plug plug;
long long map_size;
- unsigned int i, need_map_size;
+ unsigned int i, j, need_map_size;
sector_t sector;
+ unsigned int max_ra_count;
sbi->map_clu = le32_to_cpu(ep->dentry.bitmap.start_clu);
map_size = le64_to_cpu(ep->dentry.bitmap.size);
@@ -69,28 +96,43 @@ static int exfat_allocate_bitmap(struct super_block *sb,
}
sbi->map_sectors = ((need_map_size - 1) >>
(sb->s_blocksize_bits)) + 1;
- sbi->vol_amap = kmalloc_array(sbi->map_sectors,
+ sbi->vol_amap = kvmalloc_array(sbi->map_sectors,
sizeof(struct buffer_head *), GFP_KERNEL);
if (!sbi->vol_amap)
return -ENOMEM;
sector = exfat_cluster_to_sector(sbi, sbi->map_clu);
+ max_ra_count = min(sb->s_bdi->ra_pages, sb->s_bdi->io_pages) <<
+ (PAGE_SHIFT - sb->s_blocksize_bits);
for (i = 0; i < sbi->map_sectors; i++) {
- sbi->vol_amap[i] = sb_bread(sb, sector + i);
- if (!sbi->vol_amap[i]) {
- /* release all buffers and free vol_amap */
- int j = 0;
-
- while (j < i)
- brelse(sbi->vol_amap[j++]);
-
- kfree(sbi->vol_amap);
- sbi->vol_amap = NULL;
- return -EIO;
+ /* Trigger the next readahead in advance. */
+ if (max_ra_count && 0 == (i % max_ra_count)) {
+ blk_start_plug(&plug);
+ for (j = i; j < min(max_ra_count, sbi->map_sectors - i) + i; j++)
+ sb_breadahead(sb, sector + j);
+ blk_finish_plug(&plug);
}
+
+ sbi->vol_amap[i] = sb_bread(sb, sector + i);
+ if (!sbi->vol_amap[i])
+ goto err_out;
}
+ if (exfat_test_bitmap_range(sb, sbi->map_clu,
+ EXFAT_B_TO_CLU_ROUND_UP(map_size, sbi)) == false)
+ goto err_out;
+
return 0;
+
+err_out:
+ j = 0;
+ /* release all buffers and free vol_amap */
+ while (j < i)
+ brelse(sbi->vol_amap[j++]);
+
+ kvfree(sbi->vol_amap);
+ sbi->vol_amap = NULL;
+ return -EIO;
}
int exfat_load_bitmap(struct super_block *sb)
@@ -110,11 +152,8 @@ int exfat_load_bitmap(struct super_block *sb)
return -EIO;
type = exfat_get_entry_type(ep);
- if (type == TYPE_UNUSED)
- break;
- if (type != TYPE_BITMAP)
- continue;
- if (ep->dentry.bitmap.flags == 0x0) {
+ if (type == TYPE_BITMAP &&
+ ep->dentry.bitmap.flags == 0x0) {
int err;
err = exfat_allocate_bitmap(sb, ep);
@@ -122,6 +161,9 @@ int exfat_load_bitmap(struct super_block *sb)
return err;
}
brelse(bh);
+
+ if (type == TYPE_UNUSED)
+ return -EINVAL;
}
if (exfat_get_next_cluster(sb, &clu.dir))
@@ -138,17 +180,18 @@ void exfat_free_bitmap(struct exfat_sb_info *sbi)
for (i = 0; i < sbi->map_sectors; i++)
__brelse(sbi->vol_amap[i]);
- kfree(sbi->vol_amap);
+ kvfree(sbi->vol_amap);
}
-int exfat_set_bitmap(struct inode *inode, unsigned int clu, bool sync)
+int exfat_set_bitmap(struct super_block *sb, unsigned int clu, bool sync)
{
int i, b;
unsigned int ent_idx;
- struct super_block *sb = inode->i_sb;
struct exfat_sb_info *sbi = EXFAT_SB(sb);
- WARN_ON(clu < EXFAT_FIRST_CLUSTER);
+ if (!is_valid_cluster(sbi, clu))
+ return -EINVAL;
+
ent_idx = CLUSTER_TO_BITMAP_ENT(clu);
i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx);
b = BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent_idx);
@@ -158,34 +201,49 @@ int exfat_set_bitmap(struct inode *inode, unsigned int clu, bool sync)
return 0;
}
-void exfat_clear_bitmap(struct inode *inode, unsigned int clu, bool sync)
+int exfat_clear_bitmap(struct super_block *sb, unsigned int clu, bool sync)
{
int i, b;
unsigned int ent_idx;
- struct super_block *sb = inode->i_sb;
struct exfat_sb_info *sbi = EXFAT_SB(sb);
- struct exfat_mount_options *opts = &sbi->options;
- WARN_ON(clu < EXFAT_FIRST_CLUSTER);
+ if (!is_valid_cluster(sbi, clu))
+ return -EIO;
+
ent_idx = CLUSTER_TO_BITMAP_ENT(clu);
i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx);
b = BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent_idx);
+ if (!test_bit_le(b, sbi->vol_amap[i]->b_data))
+ return -EIO;
+
clear_bit_le(b, sbi->vol_amap[i]->b_data);
+
exfat_update_bh(sbi->vol_amap[i], sync);
- if (opts->discard) {
- int ret_discard;
+ return 0;
+}
+
+bool exfat_test_bitmap(struct super_block *sb, unsigned int clu)
+{
+ int i, b;
+ unsigned int ent_idx;
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+
+ if (!sbi->vol_amap)
+ return true;
- ret_discard = sb_issue_discard(sb,
- exfat_cluster_to_sector(sbi, clu),
- (1 << sbi->sect_per_clus_bits), GFP_NOFS, 0);
+ if (!is_valid_cluster(sbi, clu))
+ return false;
- if (ret_discard == -EOPNOTSUPP) {
- exfat_err(sb, "discard not supported by device, disabling");
- opts->discard = 0;
- }
- }
+ ent_idx = CLUSTER_TO_BITMAP_ENT(clu);
+ i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx);
+ b = BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent_idx);
+
+ if (!test_bit_le(b, sbi->vol_amap[i]->b_data))
+ return false;
+
+ return true;
}
/*
@@ -196,32 +254,35 @@ unsigned int exfat_find_free_bitmap(struct super_block *sb, unsigned int clu)
{
unsigned int i, map_i, map_b, ent_idx;
unsigned int clu_base, clu_free;
- unsigned char k, clu_mask;
+ unsigned long clu_bits, clu_mask;
struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ __le_long bitval;
WARN_ON(clu < EXFAT_FIRST_CLUSTER);
- ent_idx = CLUSTER_TO_BITMAP_ENT(clu);
- clu_base = BITMAP_ENT_TO_CLUSTER(ent_idx & ~(BITS_PER_BYTE_MASK));
+ ent_idx = ALIGN_DOWN(CLUSTER_TO_BITMAP_ENT(clu), BITS_PER_LONG);
+ clu_base = BITMAP_ENT_TO_CLUSTER(ent_idx);
clu_mask = IGNORED_BITS_REMAINED(clu, clu_base);
map_i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx);
map_b = BITMAP_OFFSET_BYTE_IN_SECTOR(sb, ent_idx);
for (i = EXFAT_FIRST_CLUSTER; i < sbi->num_clusters;
- i += BITS_PER_BYTE) {
- k = *(sbi->vol_amap[map_i]->b_data + map_b);
+ i += BITS_PER_LONG) {
+ bitval = *(__le_long *)(sbi->vol_amap[map_i]->b_data + map_b);
if (clu_mask > 0) {
- k |= clu_mask;
+ bitval |= cpu_to_lel(clu_mask);
clu_mask = 0;
}
- if (k < 0xFF) {
- clu_free = clu_base + free_bit[k];
+ if (lel_to_cpu(bitval) != ULONG_MAX) {
+ clu_bits = lel_to_cpu(bitval);
+ clu_free = clu_base + ffz(clu_bits);
if (clu_free < sbi->num_clusters)
return clu_free;
}
- clu_base += BITS_PER_BYTE;
+ clu_base += BITS_PER_LONG;
+ map_b += sizeof(long);
- if (++map_b >= sb->s_blocksize ||
+ if (map_b >= sb->s_blocksize ||
clu_base >= sbi->num_clusters) {
if (++map_i >= sbi->map_sectors) {
clu_base = EXFAT_FIRST_CLUSTER;
@@ -240,25 +301,24 @@ int exfat_count_used_clusters(struct super_block *sb, unsigned int *ret_count)
unsigned int count = 0;
unsigned int i, map_i = 0, map_b = 0;
unsigned int total_clus = EXFAT_DATA_CLUSTER_COUNT(sbi);
- unsigned int last_mask = total_clus & BITS_PER_BYTE_MASK;
- unsigned char clu_bits;
- const unsigned char last_bit_mask[] = {0, 0b00000001, 0b00000011,
- 0b00000111, 0b00001111, 0b00011111, 0b00111111, 0b01111111};
+ unsigned int last_mask = total_clus & (BITS_PER_LONG - 1);
+ unsigned long *bitmap, clu_bits;
total_clus &= ~last_mask;
- for (i = 0; i < total_clus; i += BITS_PER_BYTE) {
- clu_bits = *(sbi->vol_amap[map_i]->b_data + map_b);
- count += used_bit[clu_bits];
- if (++map_b >= (unsigned int)sb->s_blocksize) {
+ for (i = 0; i < total_clus; i += BITS_PER_LONG) {
+ bitmap = (void *)(sbi->vol_amap[map_i]->b_data + map_b);
+ count += hweight_long(*bitmap);
+ map_b += sizeof(long);
+ if (map_b >= (unsigned int)sb->s_blocksize) {
map_i++;
map_b = 0;
}
}
if (last_mask) {
- clu_bits = *(sbi->vol_amap[map_i]->b_data + map_b);
- clu_bits &= last_bit_mask[last_mask];
- count += used_bit[clu_bits];
+ bitmap = (void *)(sbi->vol_amap[map_i]->b_data + map_b);
+ clu_bits = lel_to_cpu(*(__le_long *)bitmap);
+ count += hweight_long(clu_bits & BITMAP_LAST_WORD_MASK(last_mask));
}
*ret_count = count;
generated by cgit (git 2.34.1) at 2025-12-25 19:53:21 +0000