return 0;
}
+static int commit_super_block(const struct exfat* ef)
+{
+ exfat_write_raw(ef->sb, sizeof(struct exfat_super_block), 0, ef->fd);
+ if (fsync(ef->fd) < 0)
+ {
+ exfat_error("fsync failed");
+ return 1;
+ }
+ return 0;
+}
+
+static int prepare_super_block(const struct exfat* ef)
+{
+ if (le16_to_cpu(ef->sb->volume_state) & EXFAT_STATE_MOUNTED)
+ exfat_warn("volume was not unmounted cleanly");
+
+ if (ef->ro)
+ return 0;
+
+ ef->sb->volume_state = cpu_to_le16(
+ le16_to_cpu(ef->sb->volume_state) | EXFAT_STATE_MOUNTED);
+ return commit_super_block(ef);
+}
+
int exfat_mount(struct exfat* ef, const char* spec, const char* options)
{
int rc;
tzset();
memset(ef, 0, sizeof(struct exfat));
- ef->sb = malloc(sizeof(struct exfat_super_block));
- if (ef->sb == NULL)
- {
- exfat_error("memory allocation failed");
- return -ENOMEM;
- }
- memset(ef->sb, 0, sizeof(struct exfat_super_block));
-
parse_options(ef, options);
ef->fd = exfat_open(spec, ef->ro);
if (ef->fd < 0)
{
- free(ef->sb);
- return -EIO;
+ if (ef->ro || !match_option(options, "ro_fallback"))
+ return -EIO;
+ ef->fd = exfat_open(spec, 1);
+ if (ef->fd < 0)
+ return -EIO;
+ exfat_warn("device is write-protected, mounting read-only");
+ ef->ro_fallback = ef->ro = 1;
}
+ ef->sb = malloc(sizeof(struct exfat_super_block));
+ if (ef->sb == NULL)
+ {
+ close(ef->fd);
+ exfat_error("failed to allocate memory for the super block");
+ return -ENOMEM;
+ }
+ memset(ef->sb, 0, sizeof(struct exfat_super_block));
+
exfat_read_raw(ef->sb, sizeof(struct exfat_super_block), 0, ef->fd);
if (memcmp(ef->sb->oem_name, "EXFAT ", 8) != 0)
{
return -EIO;
}
- ef->zero_sector = malloc(SECTOR_SIZE(*ef->sb));
- if (ef->zero_sector == NULL)
+ ef->zero_cluster = malloc(CLUSTER_SIZE(*ef->sb));
+ if (ef->zero_cluster == NULL)
{
close(ef->fd);
free(ef->sb);
exfat_error("failed to allocate zero sector");
return -ENOMEM;
}
- /* use zero_sector as a temporary buffer for VBR checksum verification */
- if (verify_vbr_checksum(ef->zero_sector, SECTOR_SIZE(*ef->sb), ef->fd) != 0)
+ /* use zero_cluster as a temporary buffer for VBR checksum verification */
+ if (verify_vbr_checksum(ef->zero_cluster, SECTOR_SIZE(*ef->sb),
+ ef->fd) != 0)
{
- free(ef->zero_sector);
+ free(ef->zero_cluster);
close(ef->fd);
free(ef->sb);
return -EIO;
}
- memset(ef->zero_sector, 0, SECTOR_SIZE(*ef->sb));
+ memset(ef->zero_cluster, 0, CLUSTER_SIZE(*ef->sb));
ef->root = malloc(sizeof(struct exfat_node));
if (ef->root == NULL)
{
- free(ef->zero_sector);
+ free(ef->zero_cluster);
close(ef->fd);
free(ef->sb);
exfat_error("failed to allocate root node");
goto error;
}
+ if (prepare_super_block(ef) != 0)
+ goto error;
+
return 0;
error:
exfat_put_node(ef, ef->root);
exfat_reset_cache(ef);
free(ef->root);
- free(ef->zero_sector);
+ free(ef->zero_cluster);
close(ef->fd);
free(ef->sb);
return -EIO;
}
+static void finalize_super_block(struct exfat* ef)
+{
+ if (ef->ro)
+ return;
+
+ ef->sb->volume_state = cpu_to_le16(
+ le16_to_cpu(ef->sb->volume_state) & ~EXFAT_STATE_MOUNTED);
+
+ /* Some implementations set the percentage of allocated space to 0xff
+ on FS creation and never update it. In this case leave it as is. */
+ if (ef->sb->allocated_percent != 0xff)
+ {
+ uint32_t free, total;
+
+ free = exfat_count_free_clusters(ef);
+ total = le32_to_cpu(ef->sb->cluster_count);
+ ef->sb->allocated_percent = ((total - free) * 100 + total / 2) / total;
+ }
+
+ commit_super_block(ef);
+}
+
void exfat_unmount(struct exfat* ef)
{
exfat_put_node(ef, ef->root);
exfat_reset_cache(ef);
free(ef->root);
ef->root = NULL;
- free(ef->zero_sector);
- ef->zero_sector = NULL;
- free(ef->cmap.chunk);
- ef->cmap.chunk = NULL;
- if (fsync(ef->fd) < 0)
- exfat_error("fsync failed");
- if (close(ef->fd) < 0)
+ finalize_super_block(ef);
+ if (close(ef->fd) < 0) /* close descriptor immediately after fsync */
exfat_error("close failed");
ef->fd = 0;
+ free(ef->zero_cluster);
+ ef->zero_cluster = NULL;
+ free(ef->cmap.chunk);
+ ef->cmap.chunk = NULL;
free(ef->sb);
ef->sb = NULL;
free(ef->upcase);