[PATCH 01/12] staging: exfat: Remove FAT/VFAT mount support, part 1

From: Valdis Kletnieks
Date: Tue Nov 12 2019 - 16:13:15 EST

Remove the top-level mount functionality, to make this driver handle
only exfat file systems.

Signed-off-by: Valdis Kletnieks <Valdis.Kletnieks@xxxxxx>
---
drivers/staging/exfat/Kconfig | 9 --
drivers/staging/exfat/exfat.h | 2 -
drivers/staging/exfat/exfat_core.c | 193 ----------------------------
drivers/staging/exfat/exfat_super.c | 8 +-
4 files changed, 1 insertion(+), 211 deletions(-)

diff --git a/drivers/staging/exfat/Kconfig b/drivers/staging/exfat/Kconfig
index ce32dfe33bec..0130019cbec2 100644
--- a/drivers/staging/exfat/Kconfig
+++ b/drivers/staging/exfat/Kconfig
@@ -6,15 +6,6 @@ config EXFAT_FS
help
This adds support for the exFAT file system.

-config EXFAT_DONT_MOUNT_VFAT
- bool "Prohibit mounting of fat/vfat filesystems by exFAT"
- depends on EXFAT_FS
- default y
- help
- By default, the exFAT driver will only mount exFAT filesystems, and refuse
- to mount fat/vfat filesystems. Set this to 'n' to allow the exFAT driver
- to mount these filesystems.
-
config EXFAT_DISCARD
bool "enable discard support"
depends on EXFAT_FS
diff --git a/drivers/staging/exfat/exfat.h b/drivers/staging/exfat/exfat.h
index 72cf40e123de..68f79e13af2b 100644
--- a/drivers/staging/exfat/exfat.h
+++ b/drivers/staging/exfat/exfat.h
@@ -915,8 +915,6 @@ s32 resolve_path(struct inode *inode, char *path, struct chain_t *p_dir,
s32 resolve_name(u8 *name, u8 **arg);

/* file operation functions */
-s32 fat16_mount(struct super_block *sb, struct pbr_sector_t *p_pbr);
-s32 fat32_mount(struct super_block *sb, struct pbr_sector_t *p_pbr);
s32 exfat_mount(struct super_block *sb, struct pbr_sector_t *p_pbr);
s32 create_dir(struct inode *inode, struct chain_t *p_dir,
struct uni_name_t *p_uniname, struct file_id_t *fid);
diff --git a/drivers/staging/exfat/exfat_core.c b/drivers/staging/exfat/exfat_core.c
index 1f0ef94bdd47..89bed7460162 100644
--- a/drivers/staging/exfat/exfat_core.c
+++ b/drivers/staging/exfat/exfat_core.c
@@ -1284,57 +1284,6 @@ s32 exfat_init_dir_entry(struct super_block *sb, struct chain_t *p_dir,
return 0;
}

-static s32 fat_init_ext_entry(struct super_block *sb, struct chain_t *p_dir,
- s32 entry, s32 num_entries,
- struct uni_name_t *p_uniname,
- struct dos_name_t *p_dosname)
-{
- int i;
- sector_t sector;
- u8 chksum;
- u16 *uniname = p_uniname->name;
- struct dos_dentry_t *dos_ep;
- struct ext_dentry_t *ext_ep;
-
- dos_ep = (struct dos_dentry_t *)get_entry_in_dir(sb, p_dir, entry,
- &sector);
- if (!dos_ep)
- return -EIO;
-
- dos_ep->lcase = p_dosname->name_case;
- memcpy(dos_ep->name, p_dosname->name, DOS_NAME_LENGTH);
- buf_modify(sb, sector);
-
- if ((--num_entries) > 0) {
- chksum = calc_checksum_1byte((void *)dos_ep->name,
- DOS_NAME_LENGTH, 0);
-
- for (i = 1; i < num_entries; i++) {
- ext_ep = (struct ext_dentry_t *)get_entry_in_dir(sb,
- p_dir,
- entry - i,
- &sector);
- if (!ext_ep)
- return -EIO;
-
- init_ext_entry(ext_ep, i, chksum, uniname);
- buf_modify(sb, sector);
- uniname += 13;
- }
-
- ext_ep = (struct ext_dentry_t *)get_entry_in_dir(sb, p_dir,
- entry - i,
- &sector);
- if (!ext_ep)
- return -EIO;
-
- init_ext_entry(ext_ep, i + 0x40, chksum, uniname);
- buf_modify(sb, sector);
- }
-
- return 0;
-}
-
static s32 exfat_init_ext_entry(struct super_block *sb, struct chain_t *p_dir,
s32 entry, s32 num_entries,
struct uni_name_t *p_uniname,
@@ -2981,148 +2930,6 @@ s32 resolve_path(struct inode *inode, char *path, struct chain_t *p_dir,
/*
* File Operation Functions
*/
-static struct fs_func fat_fs_func = {
- .alloc_cluster = fat_alloc_cluster,
- .free_cluster = fat_free_cluster,
- .count_used_clusters = fat_count_used_clusters,
-
- .init_dir_entry = fat_init_dir_entry,
- .init_ext_entry = fat_init_ext_entry,
- .find_dir_entry = fat_find_dir_entry,
- .delete_dir_entry = fat_delete_dir_entry,
- .get_uni_name_from_ext_entry = fat_get_uni_name_from_ext_entry,
- .count_ext_entries = fat_count_ext_entries,
- .calc_num_entries = fat_calc_num_entries,
-
- .get_entry_type = fat_get_entry_type,
- .set_entry_type = fat_set_entry_type,
- .get_entry_attr = fat_get_entry_attr,
- .set_entry_attr = fat_set_entry_attr,
- .get_entry_flag = fat_get_entry_flag,
- .set_entry_flag = fat_set_entry_flag,
- .get_entry_clu0 = fat_get_entry_clu0,
- .set_entry_clu0 = fat_set_entry_clu0,
- .get_entry_size = fat_get_entry_size,
- .set_entry_size = fat_set_entry_size,
- .get_entry_time = fat_get_entry_time,
- .set_entry_time = fat_set_entry_time,
-};
-
-s32 fat16_mount(struct super_block *sb, struct pbr_sector_t *p_pbr)
-{
- s32 num_reserved, num_root_sectors;
- struct bpb16_t *p_bpb = (struct bpb16_t *)p_pbr->bpb;
- struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);
- struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info);
-
- if (p_bpb->num_fats == 0)
- return -EFSCORRUPTED;
-
- num_root_sectors = GET16(p_bpb->num_root_entries) << DENTRY_SIZE_BITS;
- num_root_sectors = ((num_root_sectors - 1) >>
- p_bd->sector_size_bits) + 1;
-
- p_fs->sectors_per_clu = p_bpb->sectors_per_clu;
- p_fs->sectors_per_clu_bits = ilog2(p_bpb->sectors_per_clu);
- p_fs->cluster_size_bits = p_fs->sectors_per_clu_bits +
- p_bd->sector_size_bits;
- p_fs->cluster_size = 1 << p_fs->cluster_size_bits;
-
- p_fs->num_FAT_sectors = GET16(p_bpb->num_fat_sectors);
-
- p_fs->FAT1_start_sector = p_fs->PBR_sector + GET16(p_bpb->num_reserved);
- if (p_bpb->num_fats == 1)
- p_fs->FAT2_start_sector = p_fs->FAT1_start_sector;
- else
- p_fs->FAT2_start_sector = p_fs->FAT1_start_sector +
- p_fs->num_FAT_sectors;
-
- p_fs->root_start_sector = p_fs->FAT2_start_sector +
- p_fs->num_FAT_sectors;
- p_fs->data_start_sector = p_fs->root_start_sector + num_root_sectors;
-
- p_fs->num_sectors = GET16(p_bpb->num_sectors);
- if (p_fs->num_sectors == 0)
- p_fs->num_sectors = GET32(p_bpb->num_huge_sectors);
-
- num_reserved = p_fs->data_start_sector - p_fs->PBR_sector;
- p_fs->num_clusters = ((p_fs->num_sectors - num_reserved) >>
- p_fs->sectors_per_clu_bits) + 2;
- /* because the cluster index starts with 2 */
-
- if (p_fs->num_clusters < FAT12_THRESHOLD)
- p_fs->vol_type = FAT12;
- else
- p_fs->vol_type = FAT16;
- p_fs->vol_id = GET32(p_bpb->vol_serial);
-
- p_fs->root_dir = 0;
- p_fs->dentries_in_root = GET16(p_bpb->num_root_entries);
- p_fs->dentries_per_clu = 1 << (p_fs->cluster_size_bits -
- DENTRY_SIZE_BITS);
-
- p_fs->vol_flag = VOL_CLEAN;
- p_fs->clu_srch_ptr = 2;
- p_fs->used_clusters = UINT_MAX;
-
- p_fs->fs_func = &fat_fs_func;
-
- return 0;
-}
-
-s32 fat32_mount(struct super_block *sb, struct pbr_sector_t *p_pbr)
-{
- s32 num_reserved;
- struct bpb32_t *p_bpb = (struct bpb32_t *)p_pbr->bpb;
- struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);
- struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info);
-
- if (p_bpb->num_fats == 0)
- return -EFSCORRUPTED;
-
- p_fs->sectors_per_clu = p_bpb->sectors_per_clu;
- p_fs->sectors_per_clu_bits = ilog2(p_bpb->sectors_per_clu);
- p_fs->cluster_size_bits = p_fs->sectors_per_clu_bits +
- p_bd->sector_size_bits;
- p_fs->cluster_size = 1 << p_fs->cluster_size_bits;
-
- p_fs->num_FAT_sectors = GET32(p_bpb->num_fat32_sectors);
-
- p_fs->FAT1_start_sector = p_fs->PBR_sector + GET16(p_bpb->num_reserved);
- if (p_bpb->num_fats == 1)
- p_fs->FAT2_start_sector = p_fs->FAT1_start_sector;
- else
- p_fs->FAT2_start_sector = p_fs->FAT1_start_sector +
- p_fs->num_FAT_sectors;
-
- p_fs->root_start_sector = p_fs->FAT2_start_sector +
- p_fs->num_FAT_sectors;
- p_fs->data_start_sector = p_fs->root_start_sector;
-
- p_fs->num_sectors = GET32(p_bpb->num_huge_sectors);
- num_reserved = p_fs->data_start_sector - p_fs->PBR_sector;
-
- p_fs->num_clusters = ((p_fs->num_sectors - num_reserved) >>
- p_fs->sectors_per_clu_bits) + 2;
- /* because the cluster index starts with 2 */
-
- p_fs->vol_type = FAT32;
- p_fs->vol_id = GET32(p_bpb->vol_serial);
-
- p_fs->root_dir = GET32(p_bpb->root_cluster);
- p_fs->dentries_in_root = 0;
- p_fs->dentries_per_clu = 1 << (p_fs->cluster_size_bits -
- DENTRY_SIZE_BITS);
-
- p_fs->vol_flag = VOL_CLEAN;
- p_fs->clu_srch_ptr = 2;
- p_fs->used_clusters = UINT_MAX;
-
- p_fs->fs_func = &fat_fs_func;
-
- return 0;
-}
-
static struct fs_func exfat_fs_func = {
.alloc_cluster = exfat_alloc_cluster,
.free_cluster = exfat_free_cluster,
diff --git a/drivers/staging/exfat/exfat_super.c b/drivers/staging/exfat/exfat_super.c
index e2254d45ef6e..10e0a75765d9 100644
--- a/drivers/staging/exfat/exfat_super.c
+++ b/drivers/staging/exfat/exfat_super.c
@@ -396,16 +396,10 @@ static int ffsMountVol(struct super_block *sb)
break;

if (i < 53) {
-#ifdef CONFIG_EXFAT_DONT_MOUNT_VFAT
+ /* Not sure how we'd get here, but complain if it does */
ret = -EINVAL;
pr_info("EXFAT: Attempted to mount VFAT filesystem\n");
goto out;
-#else
- if (GET16(p_pbr->bpb + 11)) /* num_fat_sectors */
- ret = fat16_mount(sb, p_pbr);
- else
- ret = fat32_mount(sb, p_pbr);
-#endif
} else {
ret = exfat_mount(sb, p_pbr);
}
--
2.24.0