v4.19.13 snapshot.
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
new file mode 100644
index 0000000..9d7d2d5
--- /dev/null
+++ b/fs/fat/fat.h
@@ -0,0 +1,431 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _FAT_H
+#define _FAT_H
+
+#include <linux/buffer_head.h>
+#include <linux/nls.h>
+#include <linux/hash.h>
+#include <linux/ratelimit.h>
+#include <linux/msdos_fs.h>
+
+/*
+ * vfat shortname flags
+ */
+#define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */
+#define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */
+#define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */
+#define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */
+#define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */
+
+#define FAT_ERRORS_CONT 1 /* ignore error and continue */
+#define FAT_ERRORS_PANIC 2 /* panic on error */
+#define FAT_ERRORS_RO 3 /* remount r/o on error */
+
+#define FAT_NFS_STALE_RW 1 /* NFS RW support, can cause ESTALE */
+#define FAT_NFS_NOSTALE_RO 2 /* NFS RO support, no ESTALE issue */
+
+struct fat_mount_options {
+ kuid_t fs_uid;
+ kgid_t fs_gid;
+ unsigned short fs_fmask;
+ unsigned short fs_dmask;
+ unsigned short codepage; /* Codepage for shortname conversions */
+ int time_offset; /* Offset of timestamps from UTC (in minutes) */
+ char *iocharset; /* Charset used for filename input/display */
+ unsigned short shortname; /* flags for shortname display/create rule */
+ unsigned char name_check; /* r = relaxed, n = normal, s = strict */
+ unsigned char errors; /* On error: continue, panic, remount-ro */
+ unsigned char nfs; /* NFS support: nostale_ro, stale_rw */
+ unsigned short allow_utime;/* permission for setting the [am]time */
+ unsigned quiet:1, /* set = fake successful chmods and chowns */
+ showexec:1, /* set = only set x bit for com/exe/bat */
+ sys_immutable:1, /* set = system files are immutable */
+ dotsOK:1, /* set = hidden and system files are named '.filename' */
+ isvfat:1, /* 0=no vfat long filename support, 1=vfat support */
+ utf8:1, /* Use of UTF-8 character set (Default) */
+ unicode_xlate:1, /* create escape sequences for unhandled Unicode */
+ numtail:1, /* Does first alias have a numeric '~1' type tail? */
+ flush:1, /* write things quickly */
+ nocase:1, /* Does this need case conversion? 0=need case conversion*/
+ usefree:1, /* Use free_clusters for FAT32 */
+ tz_set:1, /* Filesystem timestamps' offset set */
+ rodir:1, /* allow ATTR_RO for directory */
+ discard:1, /* Issue discard requests on deletions */
+ dos1xfloppy:1; /* Assume default BPB for DOS 1.x floppies */
+};
+
+#define FAT_HASH_BITS 8
+#define FAT_HASH_SIZE (1UL << FAT_HASH_BITS)
+
+/*
+ * MS-DOS file system in-core superblock data
+ */
+struct msdos_sb_info {
+ unsigned short sec_per_clus; /* sectors/cluster */
+ unsigned short cluster_bits; /* log2(cluster_size) */
+ unsigned int cluster_size; /* cluster size */
+ unsigned char fats, fat_bits; /* number of FATs, FAT bits (12,16 or 32) */
+ unsigned short fat_start;
+ unsigned long fat_length; /* FAT start & length (sec.) */
+ unsigned long dir_start;
+ unsigned short dir_entries; /* root dir start & entries */
+ unsigned long data_start; /* first data sector */
+ unsigned long max_cluster; /* maximum cluster number */
+ unsigned long root_cluster; /* first cluster of the root directory */
+ unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */
+ struct mutex fat_lock;
+ struct mutex nfs_build_inode_lock;
+ struct mutex s_lock;
+ unsigned int prev_free; /* previously allocated cluster number */
+ unsigned int free_clusters; /* -1 if undefined */
+ unsigned int free_clus_valid; /* is free_clusters valid? */
+ struct fat_mount_options options;
+ struct nls_table *nls_disk; /* Codepage used on disk */
+ struct nls_table *nls_io; /* Charset used for input and display */
+ const void *dir_ops; /* Opaque; default directory operations */
+ int dir_per_block; /* dir entries per block */
+ int dir_per_block_bits; /* log2(dir_per_block) */
+ unsigned int vol_id; /*volume ID*/
+
+ int fatent_shift;
+ const struct fatent_operations *fatent_ops;
+ struct inode *fat_inode;
+ struct inode *fsinfo_inode;
+
+ struct ratelimit_state ratelimit;
+
+ spinlock_t inode_hash_lock;
+ struct hlist_head inode_hashtable[FAT_HASH_SIZE];
+
+ spinlock_t dir_hash_lock;
+ struct hlist_head dir_hashtable[FAT_HASH_SIZE];
+
+ unsigned int dirty; /* fs state before mount */
+ struct rcu_head rcu;
+};
+
+#define FAT_CACHE_VALID 0 /* special case for valid cache */
+
+/*
+ * MS-DOS file system inode data in memory
+ */
+struct msdos_inode_info {
+ spinlock_t cache_lru_lock;
+ struct list_head cache_lru;
+ int nr_caches;
+ /* for avoiding the race between fat_free() and fat_get_cluster() */
+ unsigned int cache_valid_id;
+
+ /* NOTE: mmu_private is 64bits, so must hold ->i_mutex to access */
+ loff_t mmu_private; /* physically allocated size */
+
+ int i_start; /* first cluster or 0 */
+ int i_logstart; /* logical first cluster */
+ int i_attrs; /* unused attribute bits */
+ loff_t i_pos; /* on-disk position of directory entry or 0 */
+ struct hlist_node i_fat_hash; /* hash by i_location */
+ struct hlist_node i_dir_hash; /* hash by i_logstart */
+ struct rw_semaphore truncate_lock; /* protect bmap against truncate */
+ struct inode vfs_inode;
+};
+
+struct fat_slot_info {
+ loff_t i_pos; /* on-disk position of directory entry */
+ loff_t slot_off; /* offset for slot or de start */
+ int nr_slots; /* number of slots + 1(de) in filename */
+ struct msdos_dir_entry *de;
+ struct buffer_head *bh;
+};
+
+static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb)
+{
+ return sb->s_fs_info;
+}
+
+static inline struct msdos_inode_info *MSDOS_I(struct inode *inode)
+{
+ return container_of(inode, struct msdos_inode_info, vfs_inode);
+}
+
+/*
+ * If ->i_mode can't hold S_IWUGO (i.e. ATTR_RO), we use ->i_attrs to
+ * save ATTR_RO instead of ->i_mode.
+ *
+ * If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only
+ * bit, it's just used as flag for app.
+ */
+static inline int fat_mode_can_hold_ro(struct inode *inode)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+ umode_t mask;
+
+ if (S_ISDIR(inode->i_mode)) {
+ if (!sbi->options.rodir)
+ return 0;
+ mask = ~sbi->options.fs_dmask;
+ } else
+ mask = ~sbi->options.fs_fmask;
+
+ if (!(mask & S_IWUGO))
+ return 0;
+ return 1;
+}
+
+/* Convert attribute bits and a mask to the UNIX mode. */
+static inline umode_t fat_make_mode(struct msdos_sb_info *sbi,
+ u8 attrs, umode_t mode)
+{
+ if (attrs & ATTR_RO && !((attrs & ATTR_DIR) && !sbi->options.rodir))
+ mode &= ~S_IWUGO;
+
+ if (attrs & ATTR_DIR)
+ return (mode & ~sbi->options.fs_dmask) | S_IFDIR;
+ else
+ return (mode & ~sbi->options.fs_fmask) | S_IFREG;
+}
+
+/* Return the FAT attribute byte for this inode */
+static inline u8 fat_make_attrs(struct inode *inode)
+{
+ u8 attrs = MSDOS_I(inode)->i_attrs;
+ if (S_ISDIR(inode->i_mode))
+ attrs |= ATTR_DIR;
+ if (fat_mode_can_hold_ro(inode) && !(inode->i_mode & S_IWUGO))
+ attrs |= ATTR_RO;
+ return attrs;
+}
+
+static inline void fat_save_attrs(struct inode *inode, u8 attrs)
+{
+ if (fat_mode_can_hold_ro(inode))
+ MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED;
+ else
+ MSDOS_I(inode)->i_attrs = attrs & (ATTR_UNUSED | ATTR_RO);
+}
+
+static inline unsigned char fat_checksum(const __u8 *name)
+{
+ unsigned char s = name[0];
+ s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2];
+ s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4];
+ s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6];
+ s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8];
+ s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10];
+ return s;
+}
+
+static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus)
+{
+ return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus
+ + sbi->data_start;
+}
+
+static inline void fat_get_blknr_offset(struct msdos_sb_info *sbi,
+ loff_t i_pos, sector_t *blknr, int *offset)
+{
+ *blknr = i_pos >> sbi->dir_per_block_bits;
+ *offset = i_pos & (sbi->dir_per_block - 1);
+}
+
+static inline loff_t fat_i_pos_read(struct msdos_sb_info *sbi,
+ struct inode *inode)
+{
+ loff_t i_pos;
+#if BITS_PER_LONG == 32
+ spin_lock(&sbi->inode_hash_lock);
+#endif
+ i_pos = MSDOS_I(inode)->i_pos;
+#if BITS_PER_LONG == 32
+ spin_unlock(&sbi->inode_hash_lock);
+#endif
+ return i_pos;
+}
+
+static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len)
+{
+#ifdef __BIG_ENDIAN
+ while (len--) {
+ *dst++ = src[0] | (src[1] << 8);
+ src += 2;
+ }
+#else
+ memcpy(dst, src, len * 2);
+#endif
+}
+
+static inline int fat_get_start(const struct msdos_sb_info *sbi,
+ const struct msdos_dir_entry *de)
+{
+ int cluster = le16_to_cpu(de->start);
+ if (sbi->fat_bits == 32)
+ cluster |= (le16_to_cpu(de->starthi) << 16);
+ return cluster;
+}
+
+static inline void fat_set_start(struct msdos_dir_entry *de, int cluster)
+{
+ de->start = cpu_to_le16(cluster);
+ de->starthi = cpu_to_le16(cluster >> 16);
+}
+
+static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len)
+{
+#ifdef __BIG_ENDIAN
+ while (len--) {
+ dst[0] = *src & 0x00FF;
+ dst[1] = (*src & 0xFF00) >> 8;
+ dst += 2;
+ src++;
+ }
+#else
+ memcpy(dst, src, len * 2);
+#endif
+}
+
+/* fat/cache.c */
+extern void fat_cache_inval_inode(struct inode *inode);
+extern int fat_get_cluster(struct inode *inode, int cluster,
+ int *fclus, int *dclus);
+extern int fat_get_mapped_cluster(struct inode *inode, sector_t sector,
+ sector_t last_block,
+ unsigned long *mapped_blocks, sector_t *bmap);
+extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
+ unsigned long *mapped_blocks, int create, bool from_bmap);
+
+/* fat/dir.c */
+extern const struct file_operations fat_dir_operations;
+extern int fat_search_long(struct inode *inode, const unsigned char *name,
+ int name_len, struct fat_slot_info *sinfo);
+extern int fat_dir_empty(struct inode *dir);
+extern int fat_subdirs(struct inode *dir);
+extern int fat_scan(struct inode *dir, const unsigned char *name,
+ struct fat_slot_info *sinfo);
+extern int fat_scan_logstart(struct inode *dir, int i_logstart,
+ struct fat_slot_info *sinfo);
+extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
+ struct msdos_dir_entry **de);
+extern int fat_alloc_new_dir(struct inode *dir, struct timespec64 *ts);
+extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
+ struct fat_slot_info *sinfo);
+extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo);
+
+/* fat/fatent.c */
+struct fat_entry {
+ int entry;
+ union {
+ u8 *ent12_p[2];
+ __le16 *ent16_p;
+ __le32 *ent32_p;
+ } u;
+ int nr_bhs;
+ struct buffer_head *bhs[2];
+ struct inode *fat_inode;
+};
+
+static inline void fatent_init(struct fat_entry *fatent)
+{
+ fatent->nr_bhs = 0;
+ fatent->entry = 0;
+ fatent->u.ent32_p = NULL;
+ fatent->bhs[0] = fatent->bhs[1] = NULL;
+ fatent->fat_inode = NULL;
+}
+
+static inline void fatent_set_entry(struct fat_entry *fatent, int entry)
+{
+ fatent->entry = entry;
+ fatent->u.ent32_p = NULL;
+}
+
+static inline void fatent_brelse(struct fat_entry *fatent)
+{
+ int i;
+ fatent->u.ent32_p = NULL;
+ for (i = 0; i < fatent->nr_bhs; i++)
+ brelse(fatent->bhs[i]);
+ fatent->nr_bhs = 0;
+ fatent->bhs[0] = fatent->bhs[1] = NULL;
+ fatent->fat_inode = NULL;
+}
+
+static inline bool fat_valid_entry(struct msdos_sb_info *sbi, int entry)
+{
+ return FAT_START_ENT <= entry && entry < sbi->max_cluster;
+}
+
+extern void fat_ent_access_init(struct super_block *sb);
+extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent,
+ int entry);
+extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent,
+ int new, int wait);
+extern int fat_alloc_clusters(struct inode *inode, int *cluster,
+ int nr_cluster);
+extern int fat_free_clusters(struct inode *inode, int cluster);
+extern int fat_count_free_clusters(struct super_block *sb);
+extern int fat_trim_fs(struct inode *inode, struct fstrim_range *range);
+
+/* fat/file.c */
+extern long fat_generic_ioctl(struct file *filp, unsigned int cmd,
+ unsigned long arg);
+extern const struct file_operations fat_file_operations;
+extern const struct inode_operations fat_file_inode_operations;
+extern int fat_setattr(struct dentry *dentry, struct iattr *attr);
+extern void fat_truncate_blocks(struct inode *inode, loff_t offset);
+extern int fat_getattr(const struct path *path, struct kstat *stat,
+ u32 request_mask, unsigned int flags);
+extern int fat_file_fsync(struct file *file, loff_t start, loff_t end,
+ int datasync);
+
+/* fat/inode.c */
+extern int fat_block_truncate_page(struct inode *inode, loff_t from);
+extern void fat_attach(struct inode *inode, loff_t i_pos);
+extern void fat_detach(struct inode *inode);
+extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos);
+extern struct inode *fat_build_inode(struct super_block *sb,
+ struct msdos_dir_entry *de, loff_t i_pos);
+extern int fat_sync_inode(struct inode *inode);
+extern int fat_fill_super(struct super_block *sb, void *data, int silent,
+ int isvfat, void (*setup)(struct super_block *));
+extern int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de);
+
+extern int fat_flush_inodes(struct super_block *sb, struct inode *i1,
+ struct inode *i2);
+static inline unsigned long fat_dir_hash(int logstart)
+{
+ return hash_32(logstart, FAT_HASH_BITS);
+}
+extern int fat_add_cluster(struct inode *inode);
+
+/* fat/misc.c */
+extern __printf(3, 4) __cold
+void __fat_fs_error(struct super_block *sb, int report, const char *fmt, ...);
+#define fat_fs_error(sb, fmt, args...) \
+ __fat_fs_error(sb, 1, fmt , ## args)
+#define fat_fs_error_ratelimit(sb, fmt, args...) \
+ __fat_fs_error(sb, __ratelimit(&MSDOS_SB(sb)->ratelimit), fmt , ## args)
+__printf(3, 4) __cold
+void fat_msg(struct super_block *sb, const char *level, const char *fmt, ...);
+#define fat_msg_ratelimit(sb, level, fmt, args...) \
+ do { \
+ if (__ratelimit(&MSDOS_SB(sb)->ratelimit)) \
+ fat_msg(sb, level, fmt, ## args); \
+ } while (0)
+extern int fat_clusters_flush(struct super_block *sb);
+extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster);
+extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec64 *ts,
+ __le16 __time, __le16 __date, u8 time_cs);
+extern void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec64 *ts,
+ __le16 *time, __le16 *date, u8 *time_cs);
+extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs);
+
+int fat_cache_init(void);
+void fat_cache_destroy(void);
+
+/* fat/nfs.c */
+extern const struct export_operations fat_export_ops;
+extern const struct export_operations fat_export_ops_nostale;
+
+/* helper for printk */
+typedef unsigned long long llu;
+
+#endif /* !_FAT_H */