Commit 04a991cd authored by Valdis Kletnieks's avatar Valdis Kletnieks Committed by Greg Kroah-Hartman
Browse files

staging: exfat: Remove FAT/VFAT mount support, part 1 



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

Signed-off-by: default avatarValdis Kletnieks <Valdis.Kletnieks@vt.edu>
Link: https://lore.kernel.org/r/20191112211238.156490-2-Valdis.Kletnieks@vt.edu


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent ecbc9e98

drivers/staging/exfat/Kconfig

+0 −9
Original line number Diff line number Diff line
@@ -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

drivers/staging/exfat/exfat.h

+0 −2
Original line number Diff line number Diff line
@@ -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);

drivers/staging/exfat/exfat_core.c

+0 −193
Original line number Diff line number Diff line
@@ -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,

drivers/staging/exfat/exfat_super.c

+1 −7
Original line number Diff line number Diff line
@@ -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);

	}

CRA Git | Maintained and supported by SUSTech CRA and CCSE