2008-11-07 04:53:46 +08:00
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#ifndef _FAT_H
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#define _FAT_H
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#include <linux/buffer_head.h>
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#include <linux/nls.h>
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2012-10-05 08:14:45 +08:00
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#include <linux/hash.h>
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2010-05-25 05:33:12 +08:00
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#include <linux/ratelimit.h>
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2008-11-07 04:53:46 +08:00
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#include <linux/msdos_fs.h>
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/*
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* vfat shortname flags
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*/
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#define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */
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#define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */
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#define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */
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#define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */
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#define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */
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2009-06-04 01:34:22 +08:00
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#define FAT_ERRORS_CONT 1 /* ignore error and continue */
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#define FAT_ERRORS_PANIC 2 /* panic on error */
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#define FAT_ERRORS_RO 3 /* remount r/o on error */
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2013-04-30 07:21:08 +08:00
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#define FAT_NFS_STALE_RW 1 /* NFS RW support, can cause ESTALE */
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#define FAT_NFS_NOSTALE_RO 2 /* NFS RO support, no ESTALE issue */
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2008-11-07 04:53:46 +08:00
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struct fat_mount_options {
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2012-02-08 08:25:39 +08:00
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kuid_t fs_uid;
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kgid_t fs_gid;
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2008-11-07 04:53:46 +08:00
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unsigned short fs_fmask;
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unsigned short fs_dmask;
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2012-10-05 08:14:52 +08:00
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unsigned short codepage; /* Codepage for shortname conversions */
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2012-12-18 08:02:58 +08:00
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int time_offset; /* Offset of timestamps from UTC (in minutes) */
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2012-10-05 08:14:52 +08:00
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char *iocharset; /* Charset used for filename input/display */
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unsigned short shortname; /* flags for shortname display/create rule */
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unsigned char name_check; /* r = relaxed, n = normal, s = strict */
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unsigned char errors; /* On error: continue, panic, remount-ro */
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2013-04-30 07:21:08 +08:00
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unsigned char nfs; /* NFS support: nostale_ro, stale_rw */
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2008-11-07 04:53:46 +08:00
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unsigned short allow_utime;/* permission for setting the [am]time */
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2012-10-05 08:14:52 +08:00
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unsigned quiet:1, /* set = fake successful chmods and chowns */
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showexec:1, /* set = only set x bit for com/exe/bat */
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sys_immutable:1, /* set = system files are immutable */
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dotsOK:1, /* set = hidden and system files are named '.filename' */
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isvfat:1, /* 0=no vfat long filename support, 1=vfat support */
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utf8:1, /* Use of UTF-8 character set (Default) */
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unicode_xlate:1, /* create escape sequences for unhandled Unicode */
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numtail:1, /* Does first alias have a numeric '~1' type tail? */
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flush:1, /* write things quickly */
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nocase:1, /* Does this need case conversion? 0=need case conversion*/
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usefree:1, /* Use free_clusters for FAT32 */
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2012-12-18 08:02:58 +08:00
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tz_set:1, /* Filesystem timestamps' offset set */
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2012-10-05 08:14:52 +08:00
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rodir:1, /* allow ATTR_RO for directory */
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2014-06-07 05:36:37 +08:00
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discard:1, /* Issue discard requests on deletions */
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dos1xfloppy:1; /* Assume default BPB for DOS 1.x floppies */
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2008-11-07 04:53:46 +08:00
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};
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#define FAT_HASH_BITS 8
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#define FAT_HASH_SIZE (1UL << FAT_HASH_BITS)
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/*
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* MS-DOS file system in-core superblock data
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*/
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struct msdos_sb_info {
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2012-10-05 08:14:52 +08:00
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unsigned short sec_per_clus; /* sectors/cluster */
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unsigned short cluster_bits; /* log2(cluster_size) */
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unsigned int cluster_size; /* cluster size */
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2015-04-17 03:47:26 +08:00
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unsigned char fats, fat_bits; /* number of FATs, FAT bits (12,16 or 32) */
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2008-11-07 04:53:46 +08:00
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unsigned short fat_start;
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2012-10-05 08:14:52 +08:00
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unsigned long fat_length; /* FAT start & length (sec.) */
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2008-11-07 04:53:46 +08:00
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unsigned long dir_start;
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2012-10-05 08:14:52 +08:00
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unsigned short dir_entries; /* root dir start & entries */
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unsigned long data_start; /* first data sector */
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unsigned long max_cluster; /* maximum cluster number */
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unsigned long root_cluster; /* first cluster of the root directory */
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unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */
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2008-11-07 04:53:46 +08:00
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struct mutex fat_lock;
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2013-04-30 07:21:12 +08:00
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struct mutex nfs_build_inode_lock;
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2012-10-06 18:40:03 +08:00
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struct mutex s_lock;
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unsigned int prev_free; /* previously allocated cluster number */
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unsigned int free_clusters; /* -1 if undefined */
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2008-11-07 04:53:46 +08:00
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unsigned int free_clus_valid; /* is free_clusters valid? */
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struct fat_mount_options options;
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2012-10-05 08:14:52 +08:00
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struct nls_table *nls_disk; /* Codepage used on disk */
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struct nls_table *nls_io; /* Charset used for input and display */
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const void *dir_ops; /* Opaque; default directory operations */
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int dir_per_block; /* dir entries per block */
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int dir_per_block_bits; /* log2(dir_per_block) */
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fatfs: add FAT_IOCTL_GET_VOLUME_ID
This patch, originally from Android kernel, adds vfat ioctl command
FAT_IOCTL_GET_VOLUME_ID, with this command we can get the vfat volume ID
using following code:
ioctl(fd, FAT_IOCTL_GET_VOLUME_ID, &volume_ID)
This patch is a modified version of the patch by Mike Lockwood, with
changes from Dmitry Pervushin, who noticed the original patch makes some
volume IDs abiguous with error returns: for example, if volume id is
0xFFFFFDAD, that matches -ENOIOCTLCMD, we get "FFFFFFFF" from the user
space.
So add a parameter to ioctl to get the correct volume ID.
Android uses vfat volume ID to identify different sd card, when a new sd
card is inserted to device, android can scan the media on it and pop up
new contents.
Signed-off-by: Bintian Wang <bintian.wang@linaro.org>
Cc: dmitry pervushin <dpervushin@gmail.com>
Cc: Mike Lockwood <lockwood@android.com>
Cc: Colin Cross <ccross@android.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Sean McNeil <sean@mcneil.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 07:00:46 +08:00
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unsigned int vol_id; /*volume ID*/
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2008-11-07 04:53:46 +08:00
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int fatent_shift;
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2016-01-21 06:59:52 +08:00
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const struct fatent_operations *fatent_ops;
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2009-06-08 01:44:36 +08:00
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struct inode *fat_inode;
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2012-06-01 07:26:12 +08:00
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struct inode *fsinfo_inode;
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2008-11-07 04:53:46 +08:00
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2010-05-25 05:33:12 +08:00
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struct ratelimit_state ratelimit;
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2008-11-07 04:53:46 +08:00
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spinlock_t inode_hash_lock;
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struct hlist_head inode_hashtable[FAT_HASH_SIZE];
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2012-10-05 08:14:45 +08:00
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spinlock_t dir_hash_lock;
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struct hlist_head dir_hashtable[FAT_HASH_SIZE];
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2013-02-28 09:03:09 +08:00
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unsigned int dirty; /* fs state before mount */
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2013-10-04 01:16:50 +08:00
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struct rcu_head rcu;
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2008-11-07 04:53:46 +08:00
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};
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#define FAT_CACHE_VALID 0 /* special case for valid cache */
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/*
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* MS-DOS file system inode data in memory
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*/
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struct msdos_inode_info {
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spinlock_t cache_lru_lock;
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struct list_head cache_lru;
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int nr_caches;
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/* for avoiding the race between fat_free() and fat_get_cluster() */
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unsigned int cache_valid_id;
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2008-11-07 04:53:57 +08:00
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/* NOTE: mmu_private is 64bits, so must hold ->i_mutex to access */
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loff_t mmu_private; /* physically allocated size */
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2008-11-07 04:53:46 +08:00
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int i_start; /* first cluster or 0 */
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int i_logstart; /* logical first cluster */
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int i_attrs; /* unused attribute bits */
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loff_t i_pos; /* on-disk position of directory entry or 0 */
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struct hlist_node i_fat_hash; /* hash by i_location */
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2012-10-05 08:14:45 +08:00
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struct hlist_node i_dir_hash; /* hash by i_logstart */
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2011-06-25 02:29:40 +08:00
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struct rw_semaphore truncate_lock; /* protect bmap against truncate */
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2008-11-07 04:53:46 +08:00
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struct inode vfs_inode;
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};
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struct fat_slot_info {
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loff_t i_pos; /* on-disk position of directory entry */
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loff_t slot_off; /* offset for slot or de start */
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int nr_slots; /* number of slots + 1(de) in filename */
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struct msdos_dir_entry *de;
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struct buffer_head *bh;
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};
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static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb)
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{
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return sb->s_fs_info;
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}
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static inline struct msdos_inode_info *MSDOS_I(struct inode *inode)
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{
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return container_of(inode, struct msdos_inode_info, vfs_inode);
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}
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2008-11-07 04:53:54 +08:00
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/*
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* If ->i_mode can't hold S_IWUGO (i.e. ATTR_RO), we use ->i_attrs to
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* save ATTR_RO instead of ->i_mode.
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2008-11-07 04:53:55 +08:00
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*
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* If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only
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* bit, it's just used as flag for app.
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2008-11-07 04:53:54 +08:00
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*/
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static inline int fat_mode_can_hold_ro(struct inode *inode)
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{
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struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
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2011-07-26 15:21:30 +08:00
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umode_t mask;
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2008-11-07 04:53:54 +08:00
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2008-11-07 04:53:55 +08:00
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if (S_ISDIR(inode->i_mode)) {
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if (!sbi->options.rodir)
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return 0;
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2008-11-07 04:53:54 +08:00
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mask = ~sbi->options.fs_dmask;
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2008-11-07 04:53:55 +08:00
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} else
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2008-11-07 04:53:54 +08:00
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mask = ~sbi->options.fs_fmask;
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if (!(mask & S_IWUGO))
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return 0;
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return 1;
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}
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2008-11-07 04:53:54 +08:00
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/* Convert attribute bits and a mask to the UNIX mode. */
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2011-07-26 15:21:30 +08:00
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static inline umode_t fat_make_mode(struct msdos_sb_info *sbi,
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u8 attrs, umode_t mode)
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2008-11-07 04:53:54 +08:00
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{
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2008-11-07 04:53:55 +08:00
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if (attrs & ATTR_RO && !((attrs & ATTR_DIR) && !sbi->options.rodir))
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2008-11-07 04:53:54 +08:00
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mode &= ~S_IWUGO;
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if (attrs & ATTR_DIR)
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return (mode & ~sbi->options.fs_dmask) | S_IFDIR;
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else
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return (mode & ~sbi->options.fs_fmask) | S_IFREG;
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}
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2008-11-07 04:53:46 +08:00
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/* Return the FAT attribute byte for this inode */
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2008-11-07 04:53:54 +08:00
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static inline u8 fat_make_attrs(struct inode *inode)
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2008-11-07 04:53:46 +08:00
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{
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2008-11-07 04:53:54 +08:00
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u8 attrs = MSDOS_I(inode)->i_attrs;
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if (S_ISDIR(inode->i_mode))
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attrs |= ATTR_DIR;
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if (fat_mode_can_hold_ro(inode) && !(inode->i_mode & S_IWUGO))
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attrs |= ATTR_RO;
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return attrs;
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2008-11-07 04:53:46 +08:00
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}
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2008-11-07 04:53:54 +08:00
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static inline void fat_save_attrs(struct inode *inode, u8 attrs)
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{
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2008-11-07 04:53:54 +08:00
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if (fat_mode_can_hold_ro(inode))
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MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED;
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else
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MSDOS_I(inode)->i_attrs = attrs & (ATTR_UNUSED | ATTR_RO);
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2008-11-07 04:53:54 +08:00
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}
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2008-11-07 04:53:46 +08:00
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static inline unsigned char fat_checksum(const __u8 *name)
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{
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unsigned char s = name[0];
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s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2];
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s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4];
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s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6];
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s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8];
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s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10];
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return s;
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}
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static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus)
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{
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return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus
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+ sbi->data_start;
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}
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2013-04-30 07:21:10 +08:00
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static inline void fat_get_blknr_offset(struct msdos_sb_info *sbi,
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loff_t i_pos, sector_t *blknr, int *offset)
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{
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*blknr = i_pos >> sbi->dir_per_block_bits;
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*offset = i_pos & (sbi->dir_per_block - 1);
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}
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2013-04-30 07:21:09 +08:00
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static inline loff_t fat_i_pos_read(struct msdos_sb_info *sbi,
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struct inode *inode)
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{
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loff_t i_pos;
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#if BITS_PER_LONG == 32
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spin_lock(&sbi->inode_hash_lock);
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#endif
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i_pos = MSDOS_I(inode)->i_pos;
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#if BITS_PER_LONG == 32
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spin_unlock(&sbi->inode_hash_lock);
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#endif
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return i_pos;
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}
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2008-11-07 04:53:46 +08:00
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static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len)
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{
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#ifdef __BIG_ENDIAN
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while (len--) {
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*dst++ = src[0] | (src[1] << 8);
|
|
|
|
|
src += 2;
|
|
|
|
|
}
|
|
|
|
|
#else
|
|
|
|
|
memcpy(dst, src, len * 2);
|
|
|
|
|
#endif
|
|
|
|
|
}
|
|
|
|
|
|
2012-07-31 05:42:13 +08:00
|
|
|
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);
|
|
|
|
|
}
|
|
|
|
|
|
2008-11-07 04:53:46 +08:00
|
|
|
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);
|
2016-01-21 06:59:46 +08:00
|
|
|
extern int fat_get_mapped_cluster(struct inode *inode, sector_t sector,
|
|
|
|
|
sector_t last_block,
|
|
|
|
|
unsigned long *mapped_blocks, sector_t *bmap);
|
2008-11-07 04:53:46 +08:00
|
|
|
extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys,
|
2016-01-21 06:59:46 +08:00
|
|
|
unsigned long *mapped_blocks, int create, bool from_bmap);
|
2008-11-07 04:53:46 +08:00
|
|
|
|
|
|
|
|
/* 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);
|
2013-04-30 07:21:14 +08:00
|
|
|
extern int fat_scan_logstart(struct inode *dir, int i_logstart,
|
|
|
|
|
struct fat_slot_info *sinfo);
|
2008-11-07 04:53:46 +08:00
|
|
|
extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
|
2012-10-05 08:14:45 +08:00
|
|
|
struct msdos_dir_entry **de);
|
2008-11-07 04:53:46 +08:00
|
|
|
extern int fat_alloc_new_dir(struct inode *dir, struct timespec *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];
|
2009-06-08 01:44:36 +08:00
|
|
|
struct inode *fat_inode;
|
2008-11-07 04:53:46 +08:00
|
|
|
};
|
|
|
|
|
|
|
|
|
|
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;
|
2009-06-08 01:44:36 +08:00
|
|
|
fatent->fat_inode = NULL;
|
2008-11-07 04:53:46 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
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;
|
2009-06-08 01:44:36 +08:00
|
|
|
fatent->fat_inode = NULL;
|
2008-11-07 04:53:46 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
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);
|
|
|
|
|
|
|
|
|
|
/* fat/file.c */
|
2010-05-17 07:13:47 +08:00
|
|
|
extern long fat_generic_ioctl(struct file *filp, unsigned int cmd,
|
|
|
|
|
unsigned long arg);
|
2008-11-07 04:53:46 +08:00
|
|
|
extern const struct file_operations fat_file_operations;
|
|
|
|
|
extern const struct inode_operations fat_file_inode_operations;
|
2012-10-05 08:14:49 +08:00
|
|
|
extern int fat_setattr(struct dentry *dentry, struct iattr *attr);
|
2010-05-26 23:05:38 +08:00
|
|
|
extern void fat_truncate_blocks(struct inode *inode, loff_t offset);
|
statx: Add a system call to make enhanced file info available
Add a system call to make extended file information available, including
file creation and some attribute flags where available through the
underlying filesystem.
The getattr inode operation is altered to take two additional arguments: a
u32 request_mask and an unsigned int flags that indicate the
synchronisation mode. This change is propagated to the vfs_getattr*()
function.
Functions like vfs_stat() are now inline wrappers around new functions
vfs_statx() and vfs_statx_fd() to reduce stack usage.
========
OVERVIEW
========
The idea was initially proposed as a set of xattrs that could be retrieved
with getxattr(), but the general preference proved to be for a new syscall
with an extended stat structure.
A number of requests were gathered for features to be included. The
following have been included:
(1) Make the fields a consistent size on all arches and make them large.
(2) Spare space, request flags and information flags are provided for
future expansion.
(3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
__s64).
(4) Creation time: The SMB protocol carries the creation time, which could
be exported by Samba, which will in turn help CIFS make use of
FS-Cache as that can be used for coherency data (stx_btime).
This is also specified in NFSv4 as a recommended attribute and could
be exported by NFSD [Steve French].
(5) Lightweight stat: Ask for just those details of interest, and allow a
netfs (such as NFS) to approximate anything not of interest, possibly
without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
Dilger] (AT_STATX_DONT_SYNC).
(6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
its cached attributes are up to date [Trond Myklebust]
(AT_STATX_FORCE_SYNC).
And the following have been left out for future extension:
(7) Data version number: Could be used by userspace NFS servers [Aneesh
Kumar].
Can also be used to modify fill_post_wcc() in NFSD which retrieves
i_version directly, but has just called vfs_getattr(). It could get
it from the kstat struct if it used vfs_xgetattr() instead.
(There's disagreement on the exact semantics of a single field, since
not all filesystems do this the same way).
(8) BSD stat compatibility: Including more fields from the BSD stat such
as creation time (st_btime) and inode generation number (st_gen)
[Jeremy Allison, Bernd Schubert].
(9) Inode generation number: Useful for FUSE and userspace NFS servers
[Bernd Schubert].
(This was asked for but later deemed unnecessary with the
open-by-handle capability available and caused disagreement as to
whether it's a security hole or not).
(10) Extra coherency data may be useful in making backups [Andreas Dilger].
(No particular data were offered, but things like last backup
timestamp, the data version number and the DOS archive bit would come
into this category).
(11) Allow the filesystem to indicate what it can/cannot provide: A
filesystem can now say it doesn't support a standard stat feature if
that isn't available, so if, for instance, inode numbers or UIDs don't
exist or are fabricated locally...
(This requires a separate system call - I have an fsinfo() call idea
for this).
(12) Store a 16-byte volume ID in the superblock that can be returned in
struct xstat [Steve French].
(Deferred to fsinfo).
(13) Include granularity fields in the time data to indicate the
granularity of each of the times (NFSv4 time_delta) [Steve French].
(Deferred to fsinfo).
(14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags.
Note that the Linux IOC flags are a mess and filesystems such as Ext4
define flags that aren't in linux/fs.h, so translation in the kernel
may be a necessity (or, possibly, we provide the filesystem type too).
(Some attributes are made available in stx_attributes, but the general
feeling was that the IOC flags were to ext[234]-specific and shouldn't
be exposed through statx this way).
(15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
Michael Kerrisk].
(Deferred, probably to fsinfo. Finding out if there's an ACL or
seclabal might require extra filesystem operations).
(16) Femtosecond-resolution timestamps [Dave Chinner].
(A __reserved field has been left in the statx_timestamp struct for
this - if there proves to be a need).
(17) A set multiple attributes syscall to go with this.
===============
NEW SYSTEM CALL
===============
The new system call is:
int ret = statx(int dfd,
const char *filename,
unsigned int flags,
unsigned int mask,
struct statx *buffer);
The dfd, filename and flags parameters indicate the file to query, in a
similar way to fstatat(). There is no equivalent of lstat() as that can be
emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is
also no equivalent of fstat() as that can be emulated by passing a NULL
filename to statx() with the fd of interest in dfd.
Whether or not statx() synchronises the attributes with the backing store
can be controlled by OR'ing a value into the flags argument (this typically
only affects network filesystems):
(1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
respect.
(2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
its attributes with the server - which might require data writeback to
occur to get the timestamps correct.
(3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
network filesystem. The resulting values should be considered
approximate.
mask is a bitmask indicating the fields in struct statx that are of
interest to the caller. The user should set this to STATX_BASIC_STATS to
get the basic set returned by stat(). It should be noted that asking for
more information may entail extra I/O operations.
buffer points to the destination for the data. This must be 256 bytes in
size.
======================
MAIN ATTRIBUTES RECORD
======================
The following structures are defined in which to return the main attribute
set:
struct statx_timestamp {
__s64 tv_sec;
__s32 tv_nsec;
__s32 __reserved;
};
struct statx {
__u32 stx_mask;
__u32 stx_blksize;
__u64 stx_attributes;
__u32 stx_nlink;
__u32 stx_uid;
__u32 stx_gid;
__u16 stx_mode;
__u16 __spare0[1];
__u64 stx_ino;
__u64 stx_size;
__u64 stx_blocks;
__u64 __spare1[1];
struct statx_timestamp stx_atime;
struct statx_timestamp stx_btime;
struct statx_timestamp stx_ctime;
struct statx_timestamp stx_mtime;
__u32 stx_rdev_major;
__u32 stx_rdev_minor;
__u32 stx_dev_major;
__u32 stx_dev_minor;
__u64 __spare2[14];
};
The defined bits in request_mask and stx_mask are:
STATX_TYPE Want/got stx_mode & S_IFMT
STATX_MODE Want/got stx_mode & ~S_IFMT
STATX_NLINK Want/got stx_nlink
STATX_UID Want/got stx_uid
STATX_GID Want/got stx_gid
STATX_ATIME Want/got stx_atime{,_ns}
STATX_MTIME Want/got stx_mtime{,_ns}
STATX_CTIME Want/got stx_ctime{,_ns}
STATX_INO Want/got stx_ino
STATX_SIZE Want/got stx_size
STATX_BLOCKS Want/got stx_blocks
STATX_BASIC_STATS [The stuff in the normal stat struct]
STATX_BTIME Want/got stx_btime{,_ns}
STATX_ALL [All currently available stuff]
stx_btime is the file creation time, stx_mask is a bitmask indicating the
data provided and __spares*[] are where as-yet undefined fields can be
placed.
Time fields are structures with separate seconds and nanoseconds fields
plus a reserved field in case we want to add even finer resolution. Note
that times will be negative if before 1970; in such a case, the nanosecond
fields will also be negative if not zero.
The bits defined in the stx_attributes field convey information about a
file, how it is accessed, where it is and what it does. The following
attributes map to FS_*_FL flags and are the same numerical value:
STATX_ATTR_COMPRESSED File is compressed by the fs
STATX_ATTR_IMMUTABLE File is marked immutable
STATX_ATTR_APPEND File is append-only
STATX_ATTR_NODUMP File is not to be dumped
STATX_ATTR_ENCRYPTED File requires key to decrypt in fs
Within the kernel, the supported flags are listed by:
KSTAT_ATTR_FS_IOC_FLAGS
[Are any other IOC flags of sufficient general interest to be exposed
through this interface?]
New flags include:
STATX_ATTR_AUTOMOUNT Object is an automount trigger
These are for the use of GUI tools that might want to mark files specially,
depending on what they are.
Fields in struct statx come in a number of classes:
(0) stx_dev_*, stx_blksize.
These are local system information and are always available.
(1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
stx_size, stx_blocks.
These will be returned whether the caller asks for them or not. The
corresponding bits in stx_mask will be set to indicate whether they
actually have valid values.
If the caller didn't ask for them, then they may be approximated. For
example, NFS won't waste any time updating them from the server,
unless as a byproduct of updating something requested.
If the values don't actually exist for the underlying object (such as
UID or GID on a DOS file), then the bit won't be set in the stx_mask,
even if the caller asked for the value. In such a case, the returned
value will be a fabrication.
Note that there are instances where the type might not be valid, for
instance Windows reparse points.
(2) stx_rdev_*.
This will be set only if stx_mode indicates we're looking at a
blockdev or a chardev, otherwise will be 0.
(3) stx_btime.
Similar to (1), except this will be set to 0 if it doesn't exist.
=======
TESTING
=======
The following test program can be used to test the statx system call:
samples/statx/test-statx.c
Just compile and run, passing it paths to the files you want to examine.
The file is built automatically if CONFIG_SAMPLES is enabled.
Here's some example output. Firstly, an NFS directory that crosses to
another FSID. Note that the AUTOMOUNT attribute is set because transiting
this directory will cause d_automount to be invoked by the VFS.
[root@andromeda ~]# /tmp/test-statx -A /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:26 Inode: 1703937 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)
Secondly, the result of automounting on that directory.
[root@andromeda ~]# /tmp/test-statx /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:27 Inode: 2 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-02-01 00:46:22 +08:00
|
|
|
extern int fat_getattr(const struct path *path, struct kstat *stat,
|
|
|
|
|
u32 request_mask, unsigned int flags);
|
2011-07-17 08:44:56 +08:00
|
|
|
extern int fat_file_fsync(struct file *file, loff_t start, loff_t end,
|
|
|
|
|
int datasync);
|
2008-11-07 04:53:46 +08:00
|
|
|
|
|
|
|
|
/* fat/inode.c */
|
2014-12-13 08:57:26 +08:00
|
|
|
extern int fat_block_truncate_page(struct inode *inode, loff_t from);
|
2008-11-07 04:53:46 +08:00
|
|
|
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,
|
2011-04-12 20:08:37 +08:00
|
|
|
int isvfat, void (*setup)(struct super_block *));
|
2013-04-30 07:21:14 +08:00
|
|
|
extern int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de);
|
2008-11-07 04:53:46 +08:00
|
|
|
|
|
|
|
|
extern int fat_flush_inodes(struct super_block *sb, struct inode *i1,
|
2012-10-05 08:14:49 +08:00
|
|
|
struct inode *i2);
|
2012-10-05 08:14:45 +08:00
|
|
|
static inline unsigned long fat_dir_hash(int logstart)
|
fat (exportfs): move NFS support code
Under memory pressure, the system may evict dentries from cache. When the
FAT driver receives a NFS request involving an evicted dentry, it is
unable to reconnect it to the filesystem root. This causes the request to
fail, often with ENOENT.
This is partially due to ineffectiveness of the current FAT NFS
implementation, and partially due to an unimplemented fh_to_parent method.
The latter can cause file accesses to fail on shares exported with
subtree_check.
This patch set provides the FAT driver with the ability to
reconnect dentries. NFS file handle generation and lookups are simplified
and made congruent with ext2.
Testing has involved a memory-starved virtual machine running 3.5-rc5 that
exports a ~2 GB vfat filesystem containing a kernel tree (~770 MB, ~40000
files, 9 levels). Both 'cp -r' and 'ls -lR' operations were performed
from a client, some overlapping, some consecutive. Exports with
'subtree_check' and 'no_subtree_check' have been tested.
Note that while this patch set improves FAT's NFS support, it does not
eliminate ESTALE errors completely.
The following should be considered for NFS clients who are sensitive to ESTALE:
* Mounting with lookupcache=none
Unfortunately this can degrade performance severely, particularly for deep
filesystems.
* Incorporating VFS patches to retry ESTALE failures on the client-side,
such as https://lkml.org/lkml/2012/6/29/381
* Handling ESTALE errors in client application code
This patch:
Move NFS-related code into its own C file. No functional changes.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:14:44 +08:00
|
|
|
{
|
2012-10-05 08:14:45 +08:00
|
|
|
return hash_32(logstart, FAT_HASH_BITS);
|
fat (exportfs): move NFS support code
Under memory pressure, the system may evict dentries from cache. When the
FAT driver receives a NFS request involving an evicted dentry, it is
unable to reconnect it to the filesystem root. This causes the request to
fail, often with ENOENT.
This is partially due to ineffectiveness of the current FAT NFS
implementation, and partially due to an unimplemented fh_to_parent method.
The latter can cause file accesses to fail on shares exported with
subtree_check.
This patch set provides the FAT driver with the ability to
reconnect dentries. NFS file handle generation and lookups are simplified
and made congruent with ext2.
Testing has involved a memory-starved virtual machine running 3.5-rc5 that
exports a ~2 GB vfat filesystem containing a kernel tree (~770 MB, ~40000
files, 9 levels). Both 'cp -r' and 'ls -lR' operations were performed
from a client, some overlapping, some consecutive. Exports with
'subtree_check' and 'no_subtree_check' have been tested.
Note that while this patch set improves FAT's NFS support, it does not
eliminate ESTALE errors completely.
The following should be considered for NFS clients who are sensitive to ESTALE:
* Mounting with lookupcache=none
Unfortunately this can degrade performance severely, particularly for deep
filesystems.
* Incorporating VFS patches to retry ESTALE failures on the client-side,
such as https://lkml.org/lkml/2012/6/29/381
* Handling ESTALE errors in client application code
This patch:
Move NFS-related code into its own C file. No functional changes.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:14:44 +08:00
|
|
|
}
|
2016-01-21 06:59:41 +08:00
|
|
|
extern int fat_add_cluster(struct inode *inode);
|
fat (exportfs): move NFS support code
Under memory pressure, the system may evict dentries from cache. When the
FAT driver receives a NFS request involving an evicted dentry, it is
unable to reconnect it to the filesystem root. This causes the request to
fail, often with ENOENT.
This is partially due to ineffectiveness of the current FAT NFS
implementation, and partially due to an unimplemented fh_to_parent method.
The latter can cause file accesses to fail on shares exported with
subtree_check.
This patch set provides the FAT driver with the ability to
reconnect dentries. NFS file handle generation and lookups are simplified
and made congruent with ext2.
Testing has involved a memory-starved virtual machine running 3.5-rc5 that
exports a ~2 GB vfat filesystem containing a kernel tree (~770 MB, ~40000
files, 9 levels). Both 'cp -r' and 'ls -lR' operations were performed
from a client, some overlapping, some consecutive. Exports with
'subtree_check' and 'no_subtree_check' have been tested.
Note that while this patch set improves FAT's NFS support, it does not
eliminate ESTALE errors completely.
The following should be considered for NFS clients who are sensitive to ESTALE:
* Mounting with lookupcache=none
Unfortunately this can degrade performance severely, particularly for deep
filesystems.
* Incorporating VFS patches to retry ESTALE failures on the client-side,
such as https://lkml.org/lkml/2012/6/29/381
* Handling ESTALE errors in client application code
This patch:
Move NFS-related code into its own C file. No functional changes.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:14:44 +08:00
|
|
|
|
2008-11-07 04:53:46 +08:00
|
|
|
/* fat/misc.c */
|
2011-11-01 08:11:33 +08:00
|
|
|
extern __printf(3, 4) __cold
|
|
|
|
|
void __fat_fs_error(struct super_block *sb, int report, const char *fmt, ...);
|
2011-04-12 20:08:38 +08:00
|
|
|
#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)
|
2011-11-01 08:11:33 +08:00
|
|
|
__printf(3, 4) __cold
|
|
|
|
|
void fat_msg(struct super_block *sb, const char *level, const char *fmt, ...);
|
2012-06-01 07:26:13 +08:00
|
|
|
#define fat_msg_ratelimit(sb, level, fmt, args...) \
|
|
|
|
|
do { \
|
|
|
|
|
if (__ratelimit(&MSDOS_SB(sb)->ratelimit)) \
|
|
|
|
|
fat_msg(sb, level, fmt, ## args); \
|
|
|
|
|
} while (0)
|
2009-09-20 00:31:58 +08:00
|
|
|
extern int fat_clusters_flush(struct super_block *sb);
|
2008-11-07 04:53:46 +08:00
|
|
|
extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster);
|
2008-11-07 04:53:47 +08:00
|
|
|
extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
|
|
|
|
|
__le16 __time, __le16 __date, u8 time_cs);
|
|
|
|
|
extern void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts,
|
|
|
|
|
__le16 *time, __le16 *date, u8 *time_cs);
|
2008-11-07 04:53:46 +08:00
|
|
|
extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs);
|
|
|
|
|
|
|
|
|
|
int fat_cache_init(void);
|
|
|
|
|
void fat_cache_destroy(void);
|
|
|
|
|
|
fat (exportfs): move NFS support code
Under memory pressure, the system may evict dentries from cache. When the
FAT driver receives a NFS request involving an evicted dentry, it is
unable to reconnect it to the filesystem root. This causes the request to
fail, often with ENOENT.
This is partially due to ineffectiveness of the current FAT NFS
implementation, and partially due to an unimplemented fh_to_parent method.
The latter can cause file accesses to fail on shares exported with
subtree_check.
This patch set provides the FAT driver with the ability to
reconnect dentries. NFS file handle generation and lookups are simplified
and made congruent with ext2.
Testing has involved a memory-starved virtual machine running 3.5-rc5 that
exports a ~2 GB vfat filesystem containing a kernel tree (~770 MB, ~40000
files, 9 levels). Both 'cp -r' and 'ls -lR' operations were performed
from a client, some overlapping, some consecutive. Exports with
'subtree_check' and 'no_subtree_check' have been tested.
Note that while this patch set improves FAT's NFS support, it does not
eliminate ESTALE errors completely.
The following should be considered for NFS clients who are sensitive to ESTALE:
* Mounting with lookupcache=none
Unfortunately this can degrade performance severely, particularly for deep
filesystems.
* Incorporating VFS patches to retry ESTALE failures on the client-side,
such as https://lkml.org/lkml/2012/6/29/381
* Handling ESTALE errors in client application code
This patch:
Move NFS-related code into its own C file. No functional changes.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:14:44 +08:00
|
|
|
/* fat/nfs.c */
|
2013-04-30 07:21:11 +08:00
|
|
|
extern const struct export_operations fat_export_ops;
|
|
|
|
|
extern const struct export_operations fat_export_ops_nostale;
|
fat (exportfs): move NFS support code
Under memory pressure, the system may evict dentries from cache. When the
FAT driver receives a NFS request involving an evicted dentry, it is
unable to reconnect it to the filesystem root. This causes the request to
fail, often with ENOENT.
This is partially due to ineffectiveness of the current FAT NFS
implementation, and partially due to an unimplemented fh_to_parent method.
The latter can cause file accesses to fail on shares exported with
subtree_check.
This patch set provides the FAT driver with the ability to
reconnect dentries. NFS file handle generation and lookups are simplified
and made congruent with ext2.
Testing has involved a memory-starved virtual machine running 3.5-rc5 that
exports a ~2 GB vfat filesystem containing a kernel tree (~770 MB, ~40000
files, 9 levels). Both 'cp -r' and 'ls -lR' operations were performed
from a client, some overlapping, some consecutive. Exports with
'subtree_check' and 'no_subtree_check' have been tested.
Note that while this patch set improves FAT's NFS support, it does not
eliminate ESTALE errors completely.
The following should be considered for NFS clients who are sensitive to ESTALE:
* Mounting with lookupcache=none
Unfortunately this can degrade performance severely, particularly for deep
filesystems.
* Incorporating VFS patches to retry ESTALE failures on the client-side,
such as https://lkml.org/lkml/2012/6/29/381
* Handling ESTALE errors in client application code
This patch:
Move NFS-related code into its own C file. No functional changes.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:14:44 +08:00
|
|
|
|
2008-11-07 04:53:58 +08:00
|
|
|
/* helper for printk */
|
|
|
|
|
typedef unsigned long long llu;
|
|
|
|
|
|
2008-11-07 04:53:46 +08:00
|
|
|
#endif /* !_FAT_H */
|