#include <errno.h>
#include <string.h>
-#define BMAP_GET(bitmap, index) ((bitmap)[(index) / 8] & (1u << ((index) % 8)))
-#define BMAP_SET(bitmap, index) (bitmap)[(index) / 8] |= (1u << ((index) % 8))
-#define BMAP_CLR(bitmap, index) (bitmap)[(index) / 8] &= ~(1u << ((index) % 8))
-
/*
- * Block to absolute offset.
+ * Sector to absolute offset.
*/
-static off_t b2o(const struct exfat* ef, off_t block)
+static off_t s2o(const struct exfat* ef, off_t sector)
{
- return block << ef->sb->block_bits;
+ return sector << ef->sb->sector_bits;
}
/*
- * Cluster to block.
+ * Cluster to sector.
*/
-static off_t c2b(const struct exfat* ef, cluster_t cluster)
+static off_t c2s(const struct exfat* ef, cluster_t cluster)
{
if (cluster < EXFAT_FIRST_DATA_CLUSTER)
exfat_bug("invalid cluster number %u", cluster);
- return le32_to_cpu(ef->sb->cluster_block_start) +
- ((off_t) (cluster - EXFAT_FIRST_DATA_CLUSTER) << ef->sb->bpc_bits);
+ return le32_to_cpu(ef->sb->cluster_sector_start) +
+ ((off_t) (cluster - EXFAT_FIRST_DATA_CLUSTER) << ef->sb->spc_bits);
}
/*
*/
off_t exfat_c2o(const struct exfat* ef, cluster_t cluster)
{
- return b2o(ef, c2b(ef, cluster));
+ return s2o(ef, c2s(ef, cluster));
+}
+
+/*
+ * Sector to cluster.
+ */
+static cluster_t s2c(const struct exfat* ef, off_t sector)
+{
+ return ((sector - le32_to_cpu(ef->sb->cluster_sector_start)) >>
+ ef->sb->spc_bits) + EXFAT_FIRST_DATA_CLUSTER;
}
/*
if (IS_CONTIGUOUS(*node))
return cluster + 1;
- fat_offset = b2o(ef, le32_to_cpu(ef->sb->fat_block_start))
+ fat_offset = s2o(ef, le32_to_cpu(ef->sb->fat_sector_start))
+ cluster * sizeof(cluster_t);
exfat_read_raw(&next, sizeof(next), fat_offset, ef->fd);
return le32_to_cpu(next);
cluster_t current, cluster_t next)
{
off_t fat_offset;
+ le32_t next_le32;
if (contiguous)
return;
- fat_offset = b2o(ef, le32_to_cpu(ef->sb->fat_block_start))
+ fat_offset = s2o(ef, le32_to_cpu(ef->sb->fat_sector_start))
+ current * sizeof(cluster_t);
- exfat_write_raw(&next, sizeof(next), fat_offset, ef->fd);
+ next_le32 = cpu_to_le32(next);
+ exfat_write_raw(&next_le32, sizeof(next_le32), fat_offset, ef->fd);
}
static cluster_t allocate_cluster(struct exfat* ef, cluster_t hint)
static void erase_raw(struct exfat* ef, size_t size, off_t offset)
{
- exfat_write_raw(ef->zero_block, size, offset, ef->fd);
+ exfat_write_raw(ef->zero_cluster, size, offset, ef->fd);
}
static int erase_range(struct exfat* ef, struct exfat_node* node,
uint64_t begin, uint64_t end)
{
- uint64_t block_boundary;
+ uint64_t cluster_boundary;
cluster_t cluster;
if (begin >= end)
return 0;
- block_boundary = (node->size | (BLOCK_SIZE(*ef->sb) - 1)) + 1;
+ cluster_boundary = (begin | (CLUSTER_SIZE(*ef->sb) - 1)) + 1;
cluster = exfat_advance_cluster(ef, node,
- node->size / CLUSTER_SIZE(*ef->sb));
+ begin / CLUSTER_SIZE(*ef->sb));
if (CLUSTER_INVALID(cluster))
{
exfat_error("invalid cluster in file");
return -EIO;
}
- /* erase from the beginning to the closest block boundary */
- erase_raw(ef, MIN(block_boundary, end) - node->size,
- exfat_c2o(ef, cluster) + node->size % CLUSTER_SIZE(*ef->sb));
- /* erase whole blocks */
- while (block_boundary < end)
+ /* erase from the beginning to the closest cluster boundary */
+ erase_raw(ef, MIN(cluster_boundary, end) - begin,
+ exfat_c2o(ef, cluster) + begin % CLUSTER_SIZE(*ef->sb));
+ /* erase whole clusters */
+ while (cluster_boundary < end)
{
- if (block_boundary % CLUSTER_SIZE(*ef->sb) == 0)
- cluster = exfat_next_cluster(ef, node, cluster);
- erase_raw(ef, BLOCK_SIZE(*ef->sb),
- exfat_c2o(ef, cluster) + block_boundary % CLUSTER_SIZE(*ef->sb));
- block_boundary += BLOCK_SIZE(*ef->sb);
+ cluster = exfat_next_cluster(ef, node, cluster);
+ /* the cluster cannot be invalid because we have just allocated it */
+ if (CLUSTER_INVALID(cluster))
+ exfat_bug("invalid cluster in file");
+ erase_raw(ef, CLUSTER_SIZE(*ef->sb), exfat_c2o(ef, cluster));
+ cluster_boundary += CLUSTER_SIZE(*ef->sb);
}
return 0;
}
uint32_t c2 = bytes2clusters(ef, size);
int rc = 0;
+ if (node->references == 0 && node->parent)
+ exfat_bug("no references, node changes can be lost");
+
if (node->size == size)
return 0;
return 0;
}
-uint32_t exfat_count_free_clusters(struct exfat* ef)
+uint32_t exfat_count_free_clusters(const struct exfat* ef)
{
uint32_t free_clusters = 0;
uint32_t i;
free_clusters++;
return free_clusters;
}
+
+static int find_used_clusters(const struct exfat* ef,
+ cluster_t* a, cluster_t* b)
+{
+ const cluster_t end = le32_to_cpu(ef->sb->cluster_count);
+
+ /* find first used cluster */
+ for (*a = *b + 1; *a < end; (*a)++)
+ if (BMAP_GET(ef->cmap.chunk, *a - EXFAT_FIRST_DATA_CLUSTER))
+ break;
+ if (*a >= end)
+ return 1;
+
+ /* find last contiguous used cluster */
+ for (*b = *a; *b < end; (*b)++)
+ if (BMAP_GET(ef->cmap.chunk, *b - EXFAT_FIRST_DATA_CLUSTER) == 0)
+ {
+ (*b)--;
+ break;
+ }
+
+ return 0;
+}
+
+int exfat_find_used_sectors(const struct exfat* ef, off_t* a, off_t* b)
+{
+ cluster_t ca, cb;
+
+ if (*a == 0 && *b == 0)
+ ca = cb = EXFAT_FIRST_DATA_CLUSTER - 1;
+ else
+ {
+ ca = s2c(ef, *a);
+ cb = s2c(ef, *b);
+ }
+ if (find_used_clusters(ef, &ca, &cb) != 0)
+ return 1;
+ if (*a != 0 || *b != 0)
+ *a = c2s(ef, ca);
+ *b = c2s(ef, cb) + (CLUSTER_SIZE(*ef->sb) - 1) / SECTOR_SIZE(*ef->sb);
+ return 0;
+}
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