Commit 181a9e80 authored by Tetsuhiro Kohada's avatar Tetsuhiro Kohada Committed by Namjae Jeon
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exfat: redefine PBR as boot_sector 



Aggregate PBR related definitions and redefine as "boot_sector" to comply
with the exFAT specification.
And, rename variable names including 'pbr'.

Signed-off-by: default avatarTetsuhiro Kohada <kohada.t2@gmail.com>
Reviewed-by: default avatarSungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: default avatarNamjae Jeon <namjae.jeon@samsung.com>
parent 943af1fd

fs/exfat/exfat_fs.h

+1 −1
Original line number Diff line number Diff line
@@ -227,7 +227,7 @@ struct exfat_sb_info { 
	unsigned int root_dir; /* root dir cluster */

	unsigned int dentries_per_clu; /* num of dentries per cluster */

	unsigned int vol_flag; /* volume dirty flag */

	struct buffer_head *pbr_bh; /* buffer_head of PBR sector */

	struct buffer_head *boot_bh; /* buffer_head of BOOT sector */



	unsigned int map_clu; /* allocation bitmap start cluster */

	unsigned int map_sectors; /* num of allocation bitmap sectors */

fs/exfat/exfat_raw.h

+29 −50
Original line number Diff line number Diff line
@@ -8,7 +8,8 @@ 


#include <linux/types.h>



#define PBR_SIGNATURE		0xAA55

#define BOOT_SIGNATURE		0xAA55

#define EXBOOT_SIGNATURE	0xAA550000



#define EXFAT_MAX_FILE_LEN	255
@@ -55,7 +56,7 @@ 


/* checksum types */

#define CS_DIR_ENTRY		0

#define CS_PBR_SECTOR		1

#define CS_BOOT_SECTOR		1

#define CS_DEFAULT		2



/* file attributes */
@@ -69,22 +70,18 @@ 
#define ATTR_RWMASK		(ATTR_HIDDEN | ATTR_SYSTEM | ATTR_VOLUME | \

				 ATTR_SUBDIR | ATTR_ARCHIVE)



#define PBR64_JUMP_BOOT_LEN		3

#define PBR64_OEM_NAME_LEN		8

#define PBR64_RESERVED_LEN		53

#define BOOTSEC_JUMP_BOOT_LEN		3

#define BOOTSEC_FS_NAME_LEN		8

#define BOOTSEC_OLDBPB_LEN		53



#define EXFAT_FILE_NAME_LEN		15



/* EXFAT BIOS parameter block (64 bytes) */

struct bpb64 {

	__u8 jmp_boot[PBR64_JUMP_BOOT_LEN];

	__u8 oem_name[PBR64_OEM_NAME_LEN];

	__u8 res_zero[PBR64_RESERVED_LEN];

} __packed;



/* EXFAT EXTEND BIOS parameter block (56 bytes) */

struct bsx64 {

	__le64 vol_offset;

/* EXFAT: Main and Backup Boot Sector (512 bytes) */

struct boot_sector {

	__u8	jmp_boot[BOOTSEC_JUMP_BOOT_LEN];

	__u8	fs_name[BOOTSEC_FS_NAME_LEN];

	__u8	must_be_zero[BOOTSEC_OLDBPB_LEN];

	__le64	partition_offset;

	__le64	vol_length;

	__le32	fat_offset;

	__le32	fat_length;
@@ -92,32 +89,14 @@ struct bsx64 { 
	__le32	clu_count;

	__le32	root_cluster;

	__le32	vol_serial;

	__u8 fs_version[2];

	__u8	fs_revision[2];

	__le16	vol_flags;

	__u8	sect_size_bits;

	__u8	sect_per_clus_bits;

	__u8	num_fats;

	__u8 phy_drv_no;

	__u8 perc_in_use;

	__u8 reserved2[7];

} __packed;



/* EXFAT PBR[BPB+BSX] (120 bytes) */

struct pbr64 {

	struct bpb64 bpb;

	struct bsx64 bsx;

} __packed;



/* Common PBR[Partition Boot Record] (512 bytes) */

struct pbr {

	union {

		__u8 raw[64];

		struct bpb64 f64;

	} bpb;

	union {

		__u8 raw[56];

		struct bsx64 f64;

	} bsx;

	__u8	drv_sel;

	__u8	percent_in_use;

	__u8	reserved[7];

	__u8	boot_code[390];

	__le16	signature;

} __packed;

fs/exfat/super.c

+42 −42
Original line number Diff line number Diff line
@@ -49,7 +49,7 @@ static void exfat_put_super(struct super_block *sb) 
		sync_blockdev(sb->s_bdev);

	exfat_set_vol_flags(sb, VOL_CLEAN);

	exfat_free_bitmap(sbi);

	brelse(sbi->pbr_bh);

	brelse(sbi->boot_bh);

	mutex_unlock(&sbi->s_lock);



	call_rcu(&sbi->rcu, exfat_delayed_free);
@@ -101,7 +101,7 @@ static int exfat_statfs(struct dentry *dentry, struct kstatfs *buf) 
int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flag)

{

	struct exfat_sb_info *sbi = EXFAT_SB(sb);

	struct pbr64 *bpb = (struct pbr64 *)sbi->pbr_bh->b_data;

	struct boot_sector *p_boot = (struct boot_sector *)sbi->boot_bh->b_data;

	bool sync;



	/* flags are not changed */
@@ -116,18 +116,18 @@ int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flag) 
	if (sb_rdonly(sb))

		return 0;



	bpb->bsx.vol_flags = cpu_to_le16(new_flag);

	p_boot->vol_flags = cpu_to_le16(new_flag);



	if (new_flag == VOL_DIRTY && !buffer_dirty(sbi->pbr_bh))

	if (new_flag == VOL_DIRTY && !buffer_dirty(sbi->boot_bh))

		sync = true;

	else

		sync = false;



	set_buffer_uptodate(sbi->pbr_bh);

	mark_buffer_dirty(sbi->pbr_bh);

	set_buffer_uptodate(sbi->boot_bh);

	mark_buffer_dirty(sbi->boot_bh);



	if (sync)

		sync_dirty_buffer(sbi->pbr_bh);

		sync_dirty_buffer(sbi->boot_bh);

	return 0;

}
@@ -366,13 +366,14 @@ static int exfat_read_root(struct inode *inode) 
	return 0;

}



static struct pbr *exfat_read_pbr_with_logical_sector(struct super_block *sb)

static struct boot_sector *exfat_read_boot_with_logical_sector(

		struct super_block *sb)

{

	struct exfat_sb_info *sbi = EXFAT_SB(sb);

	struct pbr *p_pbr = (struct pbr *) (sbi->pbr_bh)->b_data;

	struct boot_sector *p_boot = (struct boot_sector *)sbi->boot_bh->b_data;

	unsigned short logical_sect = 0;



	logical_sect = 1 << p_pbr->bsx.f64.sect_size_bits;

	logical_sect = 1 << p_boot->sect_size_bits;



	if (!is_power_of_2(logical_sect) ||

	    logical_sect < 512 || logical_sect > 4096) {
@@ -387,49 +388,48 @@ static struct pbr *exfat_read_pbr_with_logical_sector(struct super_block *sb) 
	}



	if (logical_sect > sb->s_blocksize) {

		brelse(sbi->pbr_bh);

		sbi->pbr_bh = NULL;

		brelse(sbi->boot_bh);

		sbi->boot_bh = NULL;



		if (!sb_set_blocksize(sb, logical_sect)) {

			exfat_err(sb, "unable to set blocksize %u",

				  logical_sect);

			return NULL;

		}

		sbi->pbr_bh = sb_bread(sb, 0);

		if (!sbi->pbr_bh) {

		sbi->boot_bh = sb_bread(sb, 0);

		if (!sbi->boot_bh) {

			exfat_err(sb, "unable to read boot sector (logical sector size = %lu)",

				  sb->s_blocksize);

			return NULL;

		}



		p_pbr = (struct pbr *)sbi->pbr_bh->b_data;

		p_boot = (struct boot_sector *)sbi->boot_bh->b_data;

	}

	return p_pbr;

	return p_boot;

}



/* mount the file system volume */

static int __exfat_fill_super(struct super_block *sb)

{

	int ret;

	struct pbr *p_pbr;

	struct pbr64 *p_bpb;

	struct boot_sector *p_boot;

	struct exfat_sb_info *sbi = EXFAT_SB(sb);



	/* set block size to read super block */

	sb_min_blocksize(sb, 512);



	/* read boot sector */

	sbi->pbr_bh = sb_bread(sb, 0);

	if (!sbi->pbr_bh) {

	sbi->boot_bh = sb_bread(sb, 0);

	if (!sbi->boot_bh) {

		exfat_err(sb, "unable to read boot sector");

		return -EIO;

	}



	/* PRB is read */

	p_pbr = (struct pbr *)sbi->pbr_bh->b_data;

	p_boot = (struct boot_sector *)sbi->boot_bh->b_data;



	/* check the validity of PBR */

	if (le16_to_cpu((p_pbr->signature)) != PBR_SIGNATURE) {

	/* check the validity of BOOT */

	if (le16_to_cpu((p_boot->signature)) != BOOT_SIGNATURE) {

		exfat_err(sb, "invalid boot record signature");

		ret = -EINVAL;

		goto free_bh;
@@ -437,8 +437,8 @@ static int __exfat_fill_super(struct super_block *sb) 




	/* check logical sector size */

	p_pbr = exfat_read_pbr_with_logical_sector(sb);

	if (!p_pbr) {

	p_boot = exfat_read_boot_with_logical_sector(sb);

	if (!p_boot) {

		ret = -EIO;

		goto free_bh;

	}
@@ -447,43 +447,43 @@ static int __exfat_fill_super(struct super_block *sb) 
	 * res_zero field must be filled with zero to prevent mounting

	 * from FAT volume.

	 */

	if (memchr_inv(p_pbr->bpb.f64.res_zero, 0,

			sizeof(p_pbr->bpb.f64.res_zero))) {

	if (memchr_inv(p_boot->must_be_zero, 0,

			sizeof(p_boot->must_be_zero))) {

		ret = -EINVAL;

		goto free_bh;

	}



	p_bpb = (struct pbr64 *)p_pbr;

	if (!p_bpb->bsx.num_fats) {

	p_boot = (struct boot_sector *)p_boot;

	if (!p_boot->num_fats) {

		exfat_err(sb, "bogus number of FAT structure");

		ret = -EINVAL;

		goto free_bh;

	}



	sbi->sect_per_clus = 1 << p_bpb->bsx.sect_per_clus_bits;

	sbi->sect_per_clus_bits = p_bpb->bsx.sect_per_clus_bits;

	sbi->sect_per_clus = 1 << p_boot->sect_per_clus_bits;

	sbi->sect_per_clus_bits = p_boot->sect_per_clus_bits;

	sbi->cluster_size_bits = sbi->sect_per_clus_bits + sb->s_blocksize_bits;

	sbi->cluster_size = 1 << sbi->cluster_size_bits;

	sbi->num_FAT_sectors = le32_to_cpu(p_bpb->bsx.fat_length);

	sbi->FAT1_start_sector = le32_to_cpu(p_bpb->bsx.fat_offset);

	sbi->FAT2_start_sector = p_bpb->bsx.num_fats == 1 ?

	sbi->num_FAT_sectors = le32_to_cpu(p_boot->fat_length);

	sbi->FAT1_start_sector = le32_to_cpu(p_boot->fat_offset);

	sbi->FAT2_start_sector = p_boot->num_fats == 1 ?

		sbi->FAT1_start_sector :

			sbi->FAT1_start_sector + sbi->num_FAT_sectors;

	sbi->data_start_sector = le32_to_cpu(p_bpb->bsx.clu_offset);

	sbi->num_sectors = le64_to_cpu(p_bpb->bsx.vol_length);

	sbi->data_start_sector = le32_to_cpu(p_boot->clu_offset);

	sbi->num_sectors = le64_to_cpu(p_boot->vol_length);

	/* because the cluster index starts with 2 */

	sbi->num_clusters = le32_to_cpu(p_bpb->bsx.clu_count) +

	sbi->num_clusters = le32_to_cpu(p_boot->clu_count) +

		EXFAT_RESERVED_CLUSTERS;



	sbi->root_dir = le32_to_cpu(p_bpb->bsx.root_cluster);

	sbi->root_dir = le32_to_cpu(p_boot->root_cluster);

	sbi->dentries_per_clu = 1 <<

		(sbi->cluster_size_bits - DENTRY_SIZE_BITS);



	sbi->vol_flag = le16_to_cpu(p_bpb->bsx.vol_flags);

	sbi->vol_flag = le16_to_cpu(p_boot->vol_flags);

	sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER;

	sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED;



	if (le16_to_cpu(p_bpb->bsx.vol_flags) & VOL_DIRTY) {

	if (le16_to_cpu(p_boot->vol_flags) & VOL_DIRTY) {

		sbi->vol_flag |= VOL_DIRTY;

		exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck.");

	}
@@ -517,7 +517,7 @@ free_alloc_bitmap: 
free_upcase_table:

	exfat_free_upcase_table(sbi);

free_bh:

	brelse(sbi->pbr_bh);

	brelse(sbi->boot_bh);

	return ret;

}
@@ -608,7 +608,7 @@ put_inode: 
free_table:

	exfat_free_upcase_table(sbi);

	exfat_free_bitmap(sbi);

	brelse(sbi->pbr_bh);

	brelse(sbi->boot_bh);



check_nls_io:

	unload_nls(sbi->nls_io);

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