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-rw-r--r--fs/exfat/super.c845
1 files changed, 845 insertions, 0 deletions
diff --git a/fs/exfat/super.c b/fs/exfat/super.c
new file mode 100644
index 000000000..8c32460e0
--- /dev/null
+++ b/fs/exfat/super.c
@@ -0,0 +1,845 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
+ */
+
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/mount.h>
+#include <linux/cred.h>
+#include <linux/statfs.h>
+#include <linux/seq_file.h>
+#include <linux/blkdev.h>
+#include <linux/fs_struct.h>
+#include <linux/iversion.h>
+#include <linux/nls.h>
+#include <linux/buffer_head.h>
+#include <linux/magic.h>
+
+#include "exfat_raw.h"
+#include "exfat_fs.h"
+
+static char exfat_default_iocharset[] = CONFIG_EXFAT_DEFAULT_IOCHARSET;
+static struct kmem_cache *exfat_inode_cachep;
+
+static void exfat_free_iocharset(struct exfat_sb_info *sbi)
+{
+ if (sbi->options.iocharset != exfat_default_iocharset)
+ kfree(sbi->options.iocharset);
+}
+
+static void exfat_delayed_free(struct rcu_head *p)
+{
+ struct exfat_sb_info *sbi = container_of(p, struct exfat_sb_info, rcu);
+
+ unload_nls(sbi->nls_io);
+ exfat_free_iocharset(sbi);
+ exfat_free_upcase_table(sbi);
+ kfree(sbi);
+}
+
+static void exfat_put_super(struct super_block *sb)
+{
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+
+ mutex_lock(&sbi->s_lock);
+ exfat_free_bitmap(sbi);
+ brelse(sbi->boot_bh);
+ mutex_unlock(&sbi->s_lock);
+
+ call_rcu(&sbi->rcu, exfat_delayed_free);
+}
+
+static int exfat_sync_fs(struct super_block *sb, int wait)
+{
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ int err = 0;
+
+ if (!wait)
+ return 0;
+
+ /* If there are some dirty buffers in the bdev inode */
+ mutex_lock(&sbi->s_lock);
+ sync_blockdev(sb->s_bdev);
+ if (exfat_clear_volume_dirty(sb))
+ err = -EIO;
+ mutex_unlock(&sbi->s_lock);
+ return err;
+}
+
+static int exfat_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct super_block *sb = dentry->d_sb;
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ unsigned long long id = huge_encode_dev(sb->s_bdev->bd_dev);
+
+ if (sbi->used_clusters == EXFAT_CLUSTERS_UNTRACKED) {
+ mutex_lock(&sbi->s_lock);
+ if (exfat_count_used_clusters(sb, &sbi->used_clusters)) {
+ mutex_unlock(&sbi->s_lock);
+ return -EIO;
+ }
+ mutex_unlock(&sbi->s_lock);
+ }
+
+ buf->f_type = sb->s_magic;
+ buf->f_bsize = sbi->cluster_size;
+ buf->f_blocks = sbi->num_clusters - 2; /* clu 0 & 1 */
+ buf->f_bfree = buf->f_blocks - sbi->used_clusters;
+ buf->f_bavail = buf->f_bfree;
+ buf->f_fsid = u64_to_fsid(id);
+ /* Unicode utf16 255 characters */
+ buf->f_namelen = EXFAT_MAX_FILE_LEN * NLS_MAX_CHARSET_SIZE;
+ return 0;
+}
+
+static int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flags)
+{
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ struct boot_sector *p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
+
+ /* retain persistent-flags */
+ new_flags |= sbi->vol_flags_persistent;
+
+ /* flags are not changed */
+ if (sbi->vol_flags == new_flags)
+ return 0;
+
+ sbi->vol_flags = new_flags;
+
+ /* skip updating volume dirty flag,
+ * if this volume has been mounted with read-only
+ */
+ if (sb_rdonly(sb))
+ return 0;
+
+ p_boot->vol_flags = cpu_to_le16(new_flags);
+
+ set_buffer_uptodate(sbi->boot_bh);
+ mark_buffer_dirty(sbi->boot_bh);
+
+ __sync_dirty_buffer(sbi->boot_bh, REQ_SYNC | REQ_FUA | REQ_PREFLUSH);
+
+ return 0;
+}
+
+int exfat_set_volume_dirty(struct super_block *sb)
+{
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+
+ return exfat_set_vol_flags(sb, sbi->vol_flags | VOLUME_DIRTY);
+}
+
+int exfat_clear_volume_dirty(struct super_block *sb)
+{
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+
+ return exfat_set_vol_flags(sb, sbi->vol_flags & ~VOLUME_DIRTY);
+}
+
+static int exfat_show_options(struct seq_file *m, struct dentry *root)
+{
+ struct super_block *sb = root->d_sb;
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ struct exfat_mount_options *opts = &sbi->options;
+
+ /* Show partition info */
+ if (!uid_eq(opts->fs_uid, GLOBAL_ROOT_UID))
+ seq_printf(m, ",uid=%u",
+ from_kuid_munged(&init_user_ns, opts->fs_uid));
+ if (!gid_eq(opts->fs_gid, GLOBAL_ROOT_GID))
+ seq_printf(m, ",gid=%u",
+ from_kgid_munged(&init_user_ns, opts->fs_gid));
+ seq_printf(m, ",fmask=%04o,dmask=%04o", opts->fs_fmask, opts->fs_dmask);
+ if (opts->allow_utime)
+ seq_printf(m, ",allow_utime=%04o", opts->allow_utime);
+ if (opts->utf8)
+ seq_puts(m, ",iocharset=utf8");
+ else if (sbi->nls_io)
+ seq_printf(m, ",iocharset=%s", sbi->nls_io->charset);
+ if (opts->errors == EXFAT_ERRORS_CONT)
+ seq_puts(m, ",errors=continue");
+ else if (opts->errors == EXFAT_ERRORS_PANIC)
+ seq_puts(m, ",errors=panic");
+ else
+ seq_puts(m, ",errors=remount-ro");
+ if (opts->discard)
+ seq_puts(m, ",discard");
+ if (opts->keep_last_dots)
+ seq_puts(m, ",keep_last_dots");
+ if (opts->sys_tz)
+ seq_puts(m, ",sys_tz");
+ else if (opts->time_offset)
+ seq_printf(m, ",time_offset=%d", opts->time_offset);
+ return 0;
+}
+
+static struct inode *exfat_alloc_inode(struct super_block *sb)
+{
+ struct exfat_inode_info *ei;
+
+ ei = alloc_inode_sb(sb, exfat_inode_cachep, GFP_NOFS);
+ if (!ei)
+ return NULL;
+
+ init_rwsem(&ei->truncate_lock);
+ return &ei->vfs_inode;
+}
+
+static void exfat_free_inode(struct inode *inode)
+{
+ kmem_cache_free(exfat_inode_cachep, EXFAT_I(inode));
+}
+
+static const struct super_operations exfat_sops = {
+ .alloc_inode = exfat_alloc_inode,
+ .free_inode = exfat_free_inode,
+ .write_inode = exfat_write_inode,
+ .evict_inode = exfat_evict_inode,
+ .put_super = exfat_put_super,
+ .sync_fs = exfat_sync_fs,
+ .statfs = exfat_statfs,
+ .show_options = exfat_show_options,
+};
+
+enum {
+ Opt_uid,
+ Opt_gid,
+ Opt_umask,
+ Opt_dmask,
+ Opt_fmask,
+ Opt_allow_utime,
+ Opt_charset,
+ Opt_errors,
+ Opt_discard,
+ Opt_keep_last_dots,
+ Opt_sys_tz,
+ Opt_time_offset,
+
+ /* Deprecated options */
+ Opt_utf8,
+ Opt_debug,
+ Opt_namecase,
+ Opt_codepage,
+};
+
+static const struct constant_table exfat_param_enums[] = {
+ { "continue", EXFAT_ERRORS_CONT },
+ { "panic", EXFAT_ERRORS_PANIC },
+ { "remount-ro", EXFAT_ERRORS_RO },
+ {}
+};
+
+static const struct fs_parameter_spec exfat_parameters[] = {
+ fsparam_u32("uid", Opt_uid),
+ fsparam_u32("gid", Opt_gid),
+ fsparam_u32oct("umask", Opt_umask),
+ fsparam_u32oct("dmask", Opt_dmask),
+ fsparam_u32oct("fmask", Opt_fmask),
+ fsparam_u32oct("allow_utime", Opt_allow_utime),
+ fsparam_string("iocharset", Opt_charset),
+ fsparam_enum("errors", Opt_errors, exfat_param_enums),
+ fsparam_flag("discard", Opt_discard),
+ fsparam_flag("keep_last_dots", Opt_keep_last_dots),
+ fsparam_flag("sys_tz", Opt_sys_tz),
+ fsparam_s32("time_offset", Opt_time_offset),
+ __fsparam(NULL, "utf8", Opt_utf8, fs_param_deprecated,
+ NULL),
+ __fsparam(NULL, "debug", Opt_debug, fs_param_deprecated,
+ NULL),
+ __fsparam(fs_param_is_u32, "namecase", Opt_namecase,
+ fs_param_deprecated, NULL),
+ __fsparam(fs_param_is_u32, "codepage", Opt_codepage,
+ fs_param_deprecated, NULL),
+ {}
+};
+
+static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param)
+{
+ struct exfat_sb_info *sbi = fc->s_fs_info;
+ struct exfat_mount_options *opts = &sbi->options;
+ struct fs_parse_result result;
+ int opt;
+
+ opt = fs_parse(fc, exfat_parameters, param, &result);
+ if (opt < 0)
+ return opt;
+
+ switch (opt) {
+ case Opt_uid:
+ opts->fs_uid = make_kuid(current_user_ns(), result.uint_32);
+ break;
+ case Opt_gid:
+ opts->fs_gid = make_kgid(current_user_ns(), result.uint_32);
+ break;
+ case Opt_umask:
+ opts->fs_fmask = result.uint_32;
+ opts->fs_dmask = result.uint_32;
+ break;
+ case Opt_dmask:
+ opts->fs_dmask = result.uint_32;
+ break;
+ case Opt_fmask:
+ opts->fs_fmask = result.uint_32;
+ break;
+ case Opt_allow_utime:
+ opts->allow_utime = result.uint_32 & 0022;
+ break;
+ case Opt_charset:
+ exfat_free_iocharset(sbi);
+ opts->iocharset = param->string;
+ param->string = NULL;
+ break;
+ case Opt_errors:
+ opts->errors = result.uint_32;
+ break;
+ case Opt_discard:
+ opts->discard = 1;
+ break;
+ case Opt_keep_last_dots:
+ opts->keep_last_dots = 1;
+ break;
+ case Opt_sys_tz:
+ opts->sys_tz = 1;
+ break;
+ case Opt_time_offset:
+ /*
+ * Make the limit 24 just in case someone invents something
+ * unusual.
+ */
+ if (result.int_32 < -24 * 60 || result.int_32 > 24 * 60)
+ return -EINVAL;
+ opts->time_offset = result.int_32;
+ break;
+ case Opt_utf8:
+ case Opt_debug:
+ case Opt_namecase:
+ case Opt_codepage:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void exfat_hash_init(struct super_block *sb)
+{
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ int i;
+
+ spin_lock_init(&sbi->inode_hash_lock);
+ for (i = 0; i < EXFAT_HASH_SIZE; i++)
+ INIT_HLIST_HEAD(&sbi->inode_hashtable[i]);
+}
+
+static int exfat_read_root(struct inode *inode)
+{
+ struct super_block *sb = inode->i_sb;
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ struct exfat_inode_info *ei = EXFAT_I(inode);
+ struct exfat_chain cdir;
+ int num_subdirs, num_clu = 0;
+
+ exfat_chain_set(&ei->dir, sbi->root_dir, 0, ALLOC_FAT_CHAIN);
+ ei->entry = -1;
+ ei->start_clu = sbi->root_dir;
+ ei->flags = ALLOC_FAT_CHAIN;
+ ei->type = TYPE_DIR;
+ ei->version = 0;
+ ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
+ ei->hint_stat.eidx = 0;
+ ei->hint_stat.clu = sbi->root_dir;
+ ei->hint_femp.eidx = EXFAT_HINT_NONE;
+
+ exfat_chain_set(&cdir, sbi->root_dir, 0, ALLOC_FAT_CHAIN);
+ if (exfat_count_num_clusters(sb, &cdir, &num_clu))
+ return -EIO;
+ i_size_write(inode, num_clu << sbi->cluster_size_bits);
+
+ num_subdirs = exfat_count_dir_entries(sb, &cdir);
+ if (num_subdirs < 0)
+ return -EIO;
+ set_nlink(inode, num_subdirs + EXFAT_MIN_SUBDIR);
+
+ inode->i_uid = sbi->options.fs_uid;
+ inode->i_gid = sbi->options.fs_gid;
+ inode_inc_iversion(inode);
+ inode->i_generation = 0;
+ inode->i_mode = exfat_make_mode(sbi, ATTR_SUBDIR, 0777);
+ inode->i_op = &exfat_dir_inode_operations;
+ inode->i_fop = &exfat_dir_operations;
+
+ inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >> 9;
+ ei->i_pos = ((loff_t)sbi->root_dir << 32) | 0xffffffff;
+ ei->i_size_aligned = i_size_read(inode);
+ ei->i_size_ondisk = i_size_read(inode);
+
+ exfat_save_attr(inode, ATTR_SUBDIR);
+ inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime =
+ current_time(inode);
+ exfat_truncate_atime(&inode->i_atime);
+ return 0;
+}
+
+static int exfat_calibrate_blocksize(struct super_block *sb, int logical_sect)
+{
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+
+ if (!is_power_of_2(logical_sect)) {
+ exfat_err(sb, "bogus logical sector size %u", logical_sect);
+ return -EIO;
+ }
+
+ if (logical_sect < sb->s_blocksize) {
+ exfat_err(sb, "logical sector size too small for device (logical sector size = %u)",
+ logical_sect);
+ return -EIO;
+ }
+
+ if (logical_sect > sb->s_blocksize) {
+ 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 -EIO;
+ }
+ 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 -EIO;
+ }
+ }
+ return 0;
+}
+
+static int exfat_read_boot_sector(struct super_block *sb)
+{
+ 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->boot_bh = sb_bread(sb, 0);
+ if (!sbi->boot_bh) {
+ exfat_err(sb, "unable to read boot sector");
+ return -EIO;
+ }
+ p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
+
+ /* check the validity of BOOT */
+ if (le16_to_cpu((p_boot->signature)) != BOOT_SIGNATURE) {
+ exfat_err(sb, "invalid boot record signature");
+ return -EINVAL;
+ }
+
+ if (memcmp(p_boot->fs_name, STR_EXFAT, BOOTSEC_FS_NAME_LEN)) {
+ exfat_err(sb, "invalid fs_name"); /* fs_name may unprintable */
+ return -EINVAL;
+ }
+
+ /*
+ * must_be_zero field must be filled with zero to prevent mounting
+ * from FAT volume.
+ */
+ if (memchr_inv(p_boot->must_be_zero, 0, sizeof(p_boot->must_be_zero)))
+ return -EINVAL;
+
+ if (p_boot->num_fats != 1 && p_boot->num_fats != 2) {
+ exfat_err(sb, "bogus number of FAT structure");
+ return -EINVAL;
+ }
+
+ /*
+ * sect_size_bits could be at least 9 and at most 12.
+ */
+ if (p_boot->sect_size_bits < EXFAT_MIN_SECT_SIZE_BITS ||
+ p_boot->sect_size_bits > EXFAT_MAX_SECT_SIZE_BITS) {
+ exfat_err(sb, "bogus sector size bits : %u",
+ p_boot->sect_size_bits);
+ return -EINVAL;
+ }
+
+ /*
+ * sect_per_clus_bits could be at least 0 and at most 25 - sect_size_bits.
+ */
+ if (p_boot->sect_per_clus_bits > EXFAT_MAX_SECT_PER_CLUS_BITS(p_boot)) {
+ exfat_err(sb, "bogus sectors bits per cluster : %u",
+ p_boot->sect_per_clus_bits);
+ return -EINVAL;
+ }
+
+ 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 = p_boot->sect_per_clus_bits +
+ p_boot->sect_size_bits;
+ sbi->cluster_size = 1 << sbi->cluster_size_bits;
+ 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 = le32_to_cpu(p_boot->fat_offset);
+ if (p_boot->num_fats == 2)
+ sbi->FAT2_start_sector += sbi->num_FAT_sectors;
+ 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_boot->clu_count) +
+ EXFAT_RESERVED_CLUSTERS;
+
+ sbi->root_dir = le32_to_cpu(p_boot->root_cluster);
+ sbi->dentries_per_clu = 1 <<
+ (sbi->cluster_size_bits - DENTRY_SIZE_BITS);
+
+ sbi->vol_flags = le16_to_cpu(p_boot->vol_flags);
+ sbi->vol_flags_persistent = sbi->vol_flags & (VOLUME_DIRTY | MEDIA_FAILURE);
+ sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER;
+ sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED;
+
+ /* check consistencies */
+ if ((u64)sbi->num_FAT_sectors << p_boot->sect_size_bits <
+ (u64)sbi->num_clusters * 4) {
+ exfat_err(sb, "bogus fat length");
+ return -EINVAL;
+ }
+
+ if (sbi->data_start_sector <
+ (u64)sbi->FAT1_start_sector +
+ (u64)sbi->num_FAT_sectors * p_boot->num_fats) {
+ exfat_err(sb, "bogus data start sector");
+ return -EINVAL;
+ }
+
+ if (sbi->vol_flags & VOLUME_DIRTY)
+ exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck.");
+ if (sbi->vol_flags & MEDIA_FAILURE)
+ exfat_warn(sb, "Medium has reported failures. Some data may be lost.");
+
+ /* exFAT file size is limited by a disk volume size */
+ sb->s_maxbytes = (u64)(sbi->num_clusters - EXFAT_RESERVED_CLUSTERS) <<
+ sbi->cluster_size_bits;
+
+ /* check logical sector size */
+ if (exfat_calibrate_blocksize(sb, 1 << p_boot->sect_size_bits))
+ return -EIO;
+
+ return 0;
+}
+
+static int exfat_verify_boot_region(struct super_block *sb)
+{
+ struct buffer_head *bh = NULL;
+ u32 chksum = 0;
+ __le32 *p_sig, *p_chksum;
+ int sn, i;
+
+ /* read boot sector sub-regions */
+ for (sn = 0; sn < 11; sn++) {
+ bh = sb_bread(sb, sn);
+ if (!bh)
+ return -EIO;
+
+ if (sn != 0 && sn <= 8) {
+ /* extended boot sector sub-regions */
+ p_sig = (__le32 *)&bh->b_data[sb->s_blocksize - 4];
+ if (le32_to_cpu(*p_sig) != EXBOOT_SIGNATURE)
+ exfat_warn(sb, "Invalid exboot-signature(sector = %d): 0x%08x",
+ sn, le32_to_cpu(*p_sig));
+ }
+
+ chksum = exfat_calc_chksum32(bh->b_data, sb->s_blocksize,
+ chksum, sn ? CS_DEFAULT : CS_BOOT_SECTOR);
+ brelse(bh);
+ }
+
+ /* boot checksum sub-regions */
+ bh = sb_bread(sb, sn);
+ if (!bh)
+ return -EIO;
+
+ for (i = 0; i < sb->s_blocksize; i += sizeof(u32)) {
+ p_chksum = (__le32 *)&bh->b_data[i];
+ if (le32_to_cpu(*p_chksum) != chksum) {
+ exfat_err(sb, "Invalid boot checksum (boot checksum : 0x%08x, checksum : 0x%08x)",
+ le32_to_cpu(*p_chksum), chksum);
+ brelse(bh);
+ return -EINVAL;
+ }
+ }
+ brelse(bh);
+ return 0;
+}
+
+/* mount the file system volume */
+static int __exfat_fill_super(struct super_block *sb)
+{
+ int ret;
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+
+ ret = exfat_read_boot_sector(sb);
+ if (ret) {
+ exfat_err(sb, "failed to read boot sector");
+ goto free_bh;
+ }
+
+ ret = exfat_verify_boot_region(sb);
+ if (ret) {
+ exfat_err(sb, "invalid boot region");
+ goto free_bh;
+ }
+
+ ret = exfat_create_upcase_table(sb);
+ if (ret) {
+ exfat_err(sb, "failed to load upcase table");
+ goto free_bh;
+ }
+
+ ret = exfat_load_bitmap(sb);
+ if (ret) {
+ exfat_err(sb, "failed to load alloc-bitmap");
+ goto free_upcase_table;
+ }
+
+ ret = exfat_count_used_clusters(sb, &sbi->used_clusters);
+ if (ret) {
+ exfat_err(sb, "failed to scan clusters");
+ goto free_alloc_bitmap;
+ }
+
+ return 0;
+
+free_alloc_bitmap:
+ exfat_free_bitmap(sbi);
+free_upcase_table:
+ exfat_free_upcase_table(sbi);
+free_bh:
+ brelse(sbi->boot_bh);
+ return ret;
+}
+
+static int exfat_fill_super(struct super_block *sb, struct fs_context *fc)
+{
+ struct exfat_sb_info *sbi = sb->s_fs_info;
+ struct exfat_mount_options *opts = &sbi->options;
+ struct inode *root_inode;
+ int err;
+
+ if (opts->allow_utime == (unsigned short)-1)
+ opts->allow_utime = ~opts->fs_dmask & 0022;
+
+ if (opts->discard && !bdev_max_discard_sectors(sb->s_bdev)) {
+ exfat_warn(sb, "mounting with \"discard\" option, but the device does not support discard");
+ opts->discard = 0;
+ }
+
+ sb->s_flags |= SB_NODIRATIME;
+ sb->s_magic = EXFAT_SUPER_MAGIC;
+ sb->s_op = &exfat_sops;
+
+ sb->s_time_gran = 10 * NSEC_PER_MSEC;
+ sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS;
+ sb->s_time_max = EXFAT_MAX_TIMESTAMP_SECS;
+
+ err = __exfat_fill_super(sb);
+ if (err) {
+ exfat_err(sb, "failed to recognize exfat type");
+ goto check_nls_io;
+ }
+
+ /* set up enough so that it can read an inode */
+ exfat_hash_init(sb);
+
+ if (!strcmp(sbi->options.iocharset, "utf8"))
+ opts->utf8 = 1;
+ else {
+ sbi->nls_io = load_nls(sbi->options.iocharset);
+ if (!sbi->nls_io) {
+ exfat_err(sb, "IO charset %s not found",
+ sbi->options.iocharset);
+ err = -EINVAL;
+ goto free_table;
+ }
+ }
+
+ if (sbi->options.utf8)
+ sb->s_d_op = &exfat_utf8_dentry_ops;
+ else
+ sb->s_d_op = &exfat_dentry_ops;
+
+ root_inode = new_inode(sb);
+ if (!root_inode) {
+ exfat_err(sb, "failed to allocate root inode");
+ err = -ENOMEM;
+ goto free_table;
+ }
+
+ root_inode->i_ino = EXFAT_ROOT_INO;
+ inode_set_iversion(root_inode, 1);
+ err = exfat_read_root(root_inode);
+ if (err) {
+ exfat_err(sb, "failed to initialize root inode");
+ goto put_inode;
+ }
+
+ exfat_hash_inode(root_inode, EXFAT_I(root_inode)->i_pos);
+ insert_inode_hash(root_inode);
+
+ sb->s_root = d_make_root(root_inode);
+ if (!sb->s_root) {
+ exfat_err(sb, "failed to get the root dentry");
+ err = -ENOMEM;
+ goto free_table;
+ }
+
+ return 0;
+
+put_inode:
+ iput(root_inode);
+ sb->s_root = NULL;
+
+free_table:
+ exfat_free_upcase_table(sbi);
+ exfat_free_bitmap(sbi);
+ brelse(sbi->boot_bh);
+
+check_nls_io:
+ unload_nls(sbi->nls_io);
+ exfat_free_iocharset(sbi);
+ sb->s_fs_info = NULL;
+ kfree(sbi);
+ return err;
+}
+
+static int exfat_get_tree(struct fs_context *fc)
+{
+ return get_tree_bdev(fc, exfat_fill_super);
+}
+
+static void exfat_free(struct fs_context *fc)
+{
+ struct exfat_sb_info *sbi = fc->s_fs_info;
+
+ if (sbi) {
+ exfat_free_iocharset(sbi);
+ kfree(sbi);
+ }
+}
+
+static int exfat_reconfigure(struct fs_context *fc)
+{
+ fc->sb_flags |= SB_NODIRATIME;
+
+ /* volume flag will be updated in exfat_sync_fs */
+ sync_filesystem(fc->root->d_sb);
+ return 0;
+}
+
+static const struct fs_context_operations exfat_context_ops = {
+ .parse_param = exfat_parse_param,
+ .get_tree = exfat_get_tree,
+ .free = exfat_free,
+ .reconfigure = exfat_reconfigure,
+};
+
+static int exfat_init_fs_context(struct fs_context *fc)
+{
+ struct exfat_sb_info *sbi;
+
+ sbi = kzalloc(sizeof(struct exfat_sb_info), GFP_KERNEL);
+ if (!sbi)
+ return -ENOMEM;
+
+ mutex_init(&sbi->s_lock);
+ mutex_init(&sbi->bitmap_lock);
+ ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL,
+ DEFAULT_RATELIMIT_BURST);
+
+ sbi->options.fs_uid = current_uid();
+ sbi->options.fs_gid = current_gid();
+ sbi->options.fs_fmask = current->fs->umask;
+ sbi->options.fs_dmask = current->fs->umask;
+ sbi->options.allow_utime = -1;
+ sbi->options.iocharset = exfat_default_iocharset;
+ sbi->options.errors = EXFAT_ERRORS_RO;
+
+ fc->s_fs_info = sbi;
+ fc->ops = &exfat_context_ops;
+ return 0;
+}
+
+static struct file_system_type exfat_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "exfat",
+ .init_fs_context = exfat_init_fs_context,
+ .parameters = exfat_parameters,
+ .kill_sb = kill_block_super,
+ .fs_flags = FS_REQUIRES_DEV,
+};
+
+static void exfat_inode_init_once(void *foo)
+{
+ struct exfat_inode_info *ei = (struct exfat_inode_info *)foo;
+
+ spin_lock_init(&ei->cache_lru_lock);
+ ei->nr_caches = 0;
+ ei->cache_valid_id = EXFAT_CACHE_VALID + 1;
+ INIT_LIST_HEAD(&ei->cache_lru);
+ INIT_HLIST_NODE(&ei->i_hash_fat);
+ inode_init_once(&ei->vfs_inode);
+}
+
+static int __init init_exfat_fs(void)
+{
+ int err;
+
+ err = exfat_cache_init();
+ if (err)
+ return err;
+
+ exfat_inode_cachep = kmem_cache_create("exfat_inode_cache",
+ sizeof(struct exfat_inode_info),
+ 0, SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+ exfat_inode_init_once);
+ if (!exfat_inode_cachep) {
+ err = -ENOMEM;
+ goto shutdown_cache;
+ }
+
+ err = register_filesystem(&exfat_fs_type);
+ if (err)
+ goto destroy_cache;
+
+ return 0;
+
+destroy_cache:
+ kmem_cache_destroy(exfat_inode_cachep);
+shutdown_cache:
+ exfat_cache_shutdown();
+ return err;
+}
+
+static void __exit exit_exfat_fs(void)
+{
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy cache.
+ */
+ rcu_barrier();
+ kmem_cache_destroy(exfat_inode_cachep);
+ unregister_filesystem(&exfat_fs_type);
+ exfat_cache_shutdown();
+}
+
+module_init(init_exfat_fs);
+module_exit(exit_exfat_fs);
+
+MODULE_ALIAS_FS("exfat");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("exFAT filesystem support");
+MODULE_AUTHOR("Samsung Electronics Co., Ltd.");
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-11 14:09:10 +0000