Loading fs/exfat/fatent.c 0 → 100644 +463 −0 Original line number Diff line number Diff line // SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. */ #include <linux/slab.h> #include <asm/unaligned.h> #include <linux/buffer_head.h> #include "exfat_raw.h" #include "exfat_fs.h" static int exfat_mirror_bh(struct super_block *sb, sector_t sec, struct buffer_head *bh) { struct buffer_head *c_bh; struct exfat_sb_info *sbi = EXFAT_SB(sb); sector_t sec2; int err = 0; if (sbi->FAT2_start_sector != sbi->FAT1_start_sector) { sec2 = sec - sbi->FAT1_start_sector + sbi->FAT2_start_sector; c_bh = sb_getblk(sb, sec2); if (!c_bh) return -ENOMEM; memcpy(c_bh->b_data, bh->b_data, sb->s_blocksize); set_buffer_uptodate(c_bh); mark_buffer_dirty(c_bh); if (sb->s_flags & SB_SYNCHRONOUS) err = sync_dirty_buffer(c_bh); brelse(c_bh); } return err; } static int __exfat_ent_get(struct super_block *sb, unsigned int loc, unsigned int *content) { unsigned int off; sector_t sec; struct buffer_head *bh; sec = FAT_ENT_OFFSET_SECTOR(sb, loc); off = FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc); bh = sb_bread(sb, sec); if (!bh) return -EIO; *content = le32_to_cpu(*(__le32 *)(&bh->b_data[off])); /* remap reserved clusters to simplify code */ if (*content > EXFAT_BAD_CLUSTER) *content = EXFAT_EOF_CLUSTER; brelse(bh); return 0; } int exfat_ent_set(struct super_block *sb, unsigned int loc, unsigned int content) { unsigned int off; sector_t sec; __le32 *fat_entry; struct buffer_head *bh; sec = FAT_ENT_OFFSET_SECTOR(sb, loc); off = FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc); bh = sb_bread(sb, sec); if (!bh) return -EIO; fat_entry = (__le32 *)&(bh->b_data[off]); *fat_entry = cpu_to_le32(content); exfat_update_bh(sb, bh, sb->s_flags & SB_SYNCHRONOUS); exfat_mirror_bh(sb, sec, bh); brelse(bh); return 0; } static inline bool is_valid_cluster(struct exfat_sb_info *sbi, unsigned int clus) { if (clus < EXFAT_FIRST_CLUSTER || sbi->num_clusters <= clus) return false; return true; } int exfat_ent_get(struct super_block *sb, unsigned int loc, unsigned int *content) { struct exfat_sb_info *sbi = EXFAT_SB(sb); int err; if (!is_valid_cluster(sbi, loc)) { exfat_fs_error(sb, "invalid access to FAT (entry 0x%08x)", loc); return -EIO; } err = __exfat_ent_get(sb, loc, content); if (err) { exfat_fs_error(sb, "failed to access to FAT (entry 0x%08x, err:%d)", loc, err); return err; } if (*content == EXFAT_FREE_CLUSTER) { exfat_fs_error(sb, "invalid access to FAT free cluster (entry 0x%08x)", loc); return -EIO; } if (*content == EXFAT_BAD_CLUSTER) { exfat_fs_error(sb, "invalid access to FAT bad cluster (entry 0x%08x)", loc); return -EIO; } if (*content != EXFAT_EOF_CLUSTER && !is_valid_cluster(sbi, *content)) { exfat_fs_error(sb, "invalid access to FAT (entry 0x%08x) bogus content (0x%08x)", loc, *content); return -EIO; } return 0; } int exfat_chain_cont_cluster(struct super_block *sb, unsigned int chain, unsigned int len) { if (!len) return 0; while (len > 1) { if (exfat_ent_set(sb, chain, chain + 1)) return -EIO; chain++; len--; } if (exfat_ent_set(sb, chain, EXFAT_EOF_CLUSTER)) return -EIO; return 0; } int exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain) { unsigned int num_clusters = 0; unsigned int clu; struct super_block *sb = inode->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); /* invalid cluster number */ if (p_chain->dir == EXFAT_FREE_CLUSTER || p_chain->dir == EXFAT_EOF_CLUSTER || p_chain->dir < EXFAT_FIRST_CLUSTER) return 0; /* no cluster to truncate */ if (p_chain->size == 0) return 0; /* check cluster validation */ if (p_chain->dir < 2 && p_chain->dir >= sbi->num_clusters) { exfat_msg(sb, KERN_ERR, "invalid start cluster (%u)", p_chain->dir); return -EIO; } set_bit(EXFAT_SB_DIRTY, &sbi->s_state); clu = p_chain->dir; if (p_chain->flags == ALLOC_NO_FAT_CHAIN) { do { exfat_clear_bitmap(inode, clu); clu++; num_clusters++; } while (num_clusters < p_chain->size); } else { do { exfat_clear_bitmap(inode, clu); if (exfat_get_next_cluster(sb, &clu)) goto dec_used_clus; num_clusters++; } while (clu != EXFAT_EOF_CLUSTER); } dec_used_clus: sbi->used_clusters -= num_clusters; return 0; } int exfat_find_last_cluster(struct super_block *sb, struct exfat_chain *p_chain, unsigned int *ret_clu) { unsigned int clu, next; unsigned int count = 0; next = p_chain->dir; if (p_chain->flags == ALLOC_NO_FAT_CHAIN) { *ret_clu = next + p_chain->size - 1; return 0; } do { count++; clu = next; if (exfat_ent_get(sb, clu, &next)) return -EIO; } while (next != EXFAT_EOF_CLUSTER); if (p_chain->size != count) { exfat_fs_error(sb, "bogus directory size (clus : ondisk(%d) != counted(%d))", p_chain->size, count); return -EIO; } *ret_clu = clu; return 0; } static inline int exfat_sync_bhs(struct buffer_head **bhs, int nr_bhs) { int i, err = 0; for (i = 0; i < nr_bhs; i++) write_dirty_buffer(bhs[i], 0); for (i = 0; i < nr_bhs; i++) { wait_on_buffer(bhs[i]); if (!err && !buffer_uptodate(bhs[i])) err = -EIO; } return err; } int exfat_zeroed_cluster(struct inode *dir, unsigned int clu) { struct super_block *sb = dir->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); struct buffer_head *bhs[MAX_BUF_PER_PAGE]; int nr_bhs = MAX_BUF_PER_PAGE; sector_t blknr, last_blknr; int err, i, n; blknr = exfat_cluster_to_sector(sbi, clu); last_blknr = blknr + sbi->sect_per_clus; if (last_blknr > sbi->num_sectors && sbi->num_sectors > 0) { exfat_fs_error_ratelimit(sb, "%s: out of range(sect:%llu len:%u)", __func__, (unsigned long long)blknr, sbi->sect_per_clus); return -EIO; } /* Zeroing the unused blocks on this cluster */ n = 0; while (blknr < last_blknr) { bhs[n] = sb_getblk(sb, blknr); if (!bhs[n]) { err = -ENOMEM; goto release_bhs; } memset(bhs[n]->b_data, 0, sb->s_blocksize); exfat_update_bh(sb, bhs[n], 0); n++; blknr++; if (n == nr_bhs) { if (IS_DIRSYNC(dir)) { err = exfat_sync_bhs(bhs, n); if (err) goto release_bhs; } for (i = 0; i < n; i++) brelse(bhs[i]); n = 0; } } if (IS_DIRSYNC(dir)) { err = exfat_sync_bhs(bhs, n); if (err) goto release_bhs; } for (i = 0; i < n; i++) brelse(bhs[i]); return 0; release_bhs: exfat_msg(sb, KERN_ERR, "failed zeroed sect %llu\n", (unsigned long long)blknr); for (i = 0; i < n; i++) bforget(bhs[i]); return err; } int exfat_alloc_cluster(struct inode *inode, unsigned int num_alloc, struct exfat_chain *p_chain) { int ret = -ENOSPC; unsigned int num_clusters = 0, total_cnt; unsigned int hint_clu, new_clu, last_clu = EXFAT_EOF_CLUSTER; struct super_block *sb = inode->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); total_cnt = EXFAT_DATA_CLUSTER_COUNT(sbi); if (unlikely(total_cnt < sbi->used_clusters)) { exfat_fs_error_ratelimit(sb, "%s: invalid used clusters(t:%u,u:%u)\n", __func__, total_cnt, sbi->used_clusters); return -EIO; } if (num_alloc > total_cnt - sbi->used_clusters) return -ENOSPC; hint_clu = p_chain->dir; /* find new cluster */ if (hint_clu == EXFAT_EOF_CLUSTER) { if (sbi->clu_srch_ptr < EXFAT_FIRST_CLUSTER) { exfat_msg(sb, KERN_ERR, "sbi->clu_srch_ptr is invalid (%u)\n", sbi->clu_srch_ptr); sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER; } hint_clu = exfat_find_free_bitmap(sb, sbi->clu_srch_ptr); if (hint_clu == EXFAT_EOF_CLUSTER) return -ENOSPC; } /* check cluster validation */ if (hint_clu < EXFAT_FIRST_CLUSTER && hint_clu >= sbi->num_clusters) { exfat_msg(sb, KERN_ERR, "hint_cluster is invalid (%u)\n", hint_clu); hint_clu = EXFAT_FIRST_CLUSTER; if (p_chain->flags == ALLOC_NO_FAT_CHAIN) { if (exfat_chain_cont_cluster(sb, p_chain->dir, num_clusters)) return -EIO; p_chain->flags = ALLOC_FAT_CHAIN; } } set_bit(EXFAT_SB_DIRTY, &sbi->s_state); p_chain->dir = EXFAT_EOF_CLUSTER; while ((new_clu = exfat_find_free_bitmap(sb, hint_clu)) != EXFAT_EOF_CLUSTER) { if (new_clu != hint_clu && p_chain->flags == ALLOC_NO_FAT_CHAIN) { if (exfat_chain_cont_cluster(sb, p_chain->dir, num_clusters)) { ret = -EIO; goto free_cluster; } p_chain->flags = ALLOC_FAT_CHAIN; } /* update allocation bitmap */ if (exfat_set_bitmap(inode, new_clu)) { ret = -EIO; goto free_cluster; } num_clusters++; /* update FAT table */ if (p_chain->flags == ALLOC_FAT_CHAIN) { if (exfat_ent_set(sb, new_clu, EXFAT_EOF_CLUSTER)) { ret = -EIO; goto free_cluster; } } if (p_chain->dir == EXFAT_EOF_CLUSTER) { p_chain->dir = new_clu; } else if (p_chain->flags == ALLOC_FAT_CHAIN) { if (exfat_ent_set(sb, last_clu, new_clu)) { ret = -EIO; goto free_cluster; } } last_clu = new_clu; if (--num_alloc == 0) { sbi->clu_srch_ptr = hint_clu; sbi->used_clusters += num_clusters; p_chain->size += num_clusters; return 0; } hint_clu = new_clu + 1; if (hint_clu >= sbi->num_clusters) { hint_clu = EXFAT_FIRST_CLUSTER; if (p_chain->flags == ALLOC_NO_FAT_CHAIN) { if (exfat_chain_cont_cluster(sb, p_chain->dir, num_clusters)) { ret = -EIO; goto free_cluster; } p_chain->flags = ALLOC_FAT_CHAIN; } } } free_cluster: if (num_clusters) exfat_free_cluster(inode, p_chain); return ret; } int exfat_count_num_clusters(struct super_block *sb, struct exfat_chain *p_chain, unsigned int *ret_count) { unsigned int i, count; unsigned int clu; struct exfat_sb_info *sbi = EXFAT_SB(sb); if (!p_chain->dir || p_chain->dir == EXFAT_EOF_CLUSTER) { *ret_count = 0; return 0; } if (p_chain->flags == ALLOC_NO_FAT_CHAIN) { *ret_count = p_chain->size; return 0; } clu = p_chain->dir; count = 0; for (i = EXFAT_FIRST_CLUSTER; i < sbi->num_clusters; i++) { count++; if (exfat_ent_get(sb, clu, &clu)) return -EIO; if (clu == EXFAT_EOF_CLUSTER) break; } *ret_count = count; return 0; } No newline at end of file fs/exfat/file.c 0 → 100644 +360 −0 Original line number Diff line number Diff line // SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. */ #include <linux/slab.h> #include <linux/cred.h> #include <linux/buffer_head.h> #include "exfat_raw.h" #include "exfat_fs.h" static int exfat_cont_expand(struct inode *inode, loff_t size) { struct address_space *mapping = inode->i_mapping; loff_t start = i_size_read(inode), count = size - i_size_read(inode); int err, err2; err = generic_cont_expand_simple(inode, size); if (err) return err; inode->i_ctime = inode->i_mtime = current_time(inode); mark_inode_dirty(inode); if (!IS_SYNC(inode)) return 0; err = filemap_fdatawrite_range(mapping, start, start + count - 1); err2 = sync_mapping_buffers(mapping); if (!err) err = err2; err2 = write_inode_now(inode, 1); if (!err) err = err2; if (err) return err; return filemap_fdatawait_range(mapping, start, start + count - 1); } static bool exfat_allow_set_time(struct exfat_sb_info *sbi, struct inode *inode) { mode_t allow_utime = sbi->options.allow_utime; if (!uid_eq(current_fsuid(), inode->i_uid)) { if (in_group_p(inode->i_gid)) allow_utime >>= 3; if (allow_utime & MAY_WRITE) return true; } /* use a default check */ return false; } static int exfat_sanitize_mode(const struct exfat_sb_info *sbi, struct inode *inode, umode_t *mode_ptr) { mode_t i_mode, mask, perm; i_mode = inode->i_mode; mask = (S_ISREG(i_mode) || S_ISLNK(i_mode)) ? sbi->options.fs_fmask : sbi->options.fs_dmask; perm = *mode_ptr & ~(S_IFMT | mask); /* Of the r and x bits, all (subject to umask) must be present.*/ if ((perm & 0555) != (i_mode & 0555)) return -EPERM; if (exfat_mode_can_hold_ro(inode)) { /* * Of the w bits, either all (subject to umask) or none must * be present. */ if ((perm & 0222) && ((perm & 0222) != (0222 & ~mask))) return -EPERM; } else { /* * If exfat_mode_can_hold_ro(inode) is false, can't change * w bits. */ if ((perm & 0222) != (0222 & ~mask)) return -EPERM; } *mode_ptr &= S_IFMT | perm; return 0; } /* resize the file length */ int __exfat_truncate(struct inode *inode, loff_t new_size) { unsigned int num_clusters_new, num_clusters_phys; unsigned int last_clu = EXFAT_FREE_CLUSTER; struct exfat_chain clu; struct exfat_dentry *ep, *ep2; 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_entry_set_cache *es = NULL; int evict = (ei->dir.dir == DIR_DELETED) ? 1 : 0; /* check if the given file ID is opened */ if (ei->type != TYPE_FILE && ei->type != TYPE_DIR) return -EPERM; exfat_set_vol_flags(sb, VOL_DIRTY); num_clusters_new = EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi); num_clusters_phys = EXFAT_B_TO_CLU_ROUND_UP(EXFAT_I(inode)->i_size_ondisk, sbi); exfat_chain_set(&clu, ei->start_clu, num_clusters_phys, ei->flags); if (new_size > 0) { /* * Truncate FAT chain num_clusters after the first cluster * num_clusters = min(new, phys); */ unsigned int num_clusters = min(num_clusters_new, num_clusters_phys); /* * Follow FAT chain * (defensive coding - works fine even with corrupted FAT table */ if (clu.flags == ALLOC_NO_FAT_CHAIN) { clu.dir += num_clusters; clu.size -= num_clusters; } else { while (num_clusters > 0) { last_clu = clu.dir; if (exfat_get_next_cluster(sb, &(clu.dir))) return -EIO; num_clusters--; clu.size--; } } } else { ei->flags = ALLOC_NO_FAT_CHAIN; ei->start_clu = EXFAT_EOF_CLUSTER; } i_size_write(inode, new_size); if (ei->type == TYPE_FILE) ei->attr |= ATTR_ARCHIVE; /* update the directory entry */ if (!evict) { struct timespec64 ts; es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES, &ep); if (!es) return -EIO; ep2 = ep + 1; ts = current_time(inode); exfat_set_entry_time(sbi, &ts, &ep->dentry.file.modify_tz, &ep->dentry.file.modify_time, &ep->dentry.file.modify_date, &ep->dentry.file.modify_time_ms); ep->dentry.file.attr = cpu_to_le16(ei->attr); /* File size should be zero if there is no cluster allocated */ if (ei->start_clu == EXFAT_EOF_CLUSTER) { ep->dentry.stream.valid_size = 0; ep->dentry.stream.size = 0; } else { ep->dentry.stream.valid_size = cpu_to_le64(new_size); ep->dentry.stream.size = ep->dentry.stream.valid_size; } if (new_size == 0) { /* Any directory can not be truncated to zero */ WARN_ON(ei->type != TYPE_FILE); ep2->dentry.stream.flags = ALLOC_FAT_CHAIN; ep2->dentry.stream.start_clu = EXFAT_FREE_CLUSTER; } if (exfat_update_dir_chksum_with_entry_set(sb, es, inode_needs_sync(inode))) return -EIO; kfree(es); } /* cut off from the FAT chain */ if (ei->flags == ALLOC_FAT_CHAIN && last_clu != EXFAT_FREE_CLUSTER && last_clu != EXFAT_EOF_CLUSTER) { if (exfat_ent_set(sb, last_clu, EXFAT_EOF_CLUSTER)) return -EIO; } /* invalidate cache and free the clusters */ /* clear exfat cache */ exfat_cache_inval_inode(inode); /* hint information */ ei->hint_bmap.off = EXFAT_EOF_CLUSTER; ei->hint_bmap.clu = EXFAT_EOF_CLUSTER; if (ei->rwoffset > new_size) ei->rwoffset = new_size; /* hint_stat will be used if this is directory. */ ei->hint_stat.eidx = 0; ei->hint_stat.clu = ei->start_clu; ei->hint_femp.eidx = EXFAT_HINT_NONE; /* free the clusters */ if (exfat_free_cluster(inode, &clu)) return -EIO; exfat_set_vol_flags(sb, VOL_CLEAN); return 0; } void exfat_truncate(struct inode *inode, loff_t size) { struct super_block *sb = inode->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); unsigned int blocksize = 1 << inode->i_blkbits; loff_t aligned_size; int err; mutex_lock(&sbi->s_lock); if (EXFAT_I(inode)->start_clu == 0) { /* * Empty start_clu != ~0 (not allocated) */ exfat_fs_error(sb, "tried to truncate zeroed cluster."); goto write_size; } err = __exfat_truncate(inode, i_size_read(inode)); if (err) goto write_size; inode->i_ctime = inode->i_mtime = current_time(inode); if (IS_DIRSYNC(inode)) exfat_sync_inode(inode); else mark_inode_dirty(inode); inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) & ~(sbi->cluster_size - 1)) >> inode->i_blkbits; write_size: aligned_size = i_size_read(inode); if (aligned_size & (blocksize - 1)) { aligned_size |= (blocksize - 1); aligned_size++; } if (EXFAT_I(inode)->i_size_ondisk > i_size_read(inode)) EXFAT_I(inode)->i_size_ondisk = aligned_size; if (EXFAT_I(inode)->i_size_aligned > i_size_read(inode)) EXFAT_I(inode)->i_size_aligned = aligned_size; mutex_unlock(&sbi->s_lock); } int exfat_getattr(const struct path *path, struct kstat *stat, unsigned int request_mask, unsigned int query_flags) { struct inode *inode = d_backing_inode(path->dentry); struct exfat_inode_info *ei = EXFAT_I(inode); generic_fillattr(inode, stat); stat->result_mask |= STATX_BTIME; stat->btime.tv_sec = ei->i_crtime.tv_sec; stat->btime.tv_nsec = ei->i_crtime.tv_nsec; stat->blksize = EXFAT_SB(inode->i_sb)->cluster_size; return 0; } int exfat_setattr(struct dentry *dentry, struct iattr *attr) { struct exfat_sb_info *sbi = EXFAT_SB(dentry->d_sb); struct inode *inode = dentry->d_inode; unsigned int ia_valid; int error; if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size > i_size_read(inode)) { error = exfat_cont_expand(inode, attr->ia_size); if (error || attr->ia_valid == ATTR_SIZE) return error; attr->ia_valid &= ~ATTR_SIZE; } /* Check for setting the inode time. */ ia_valid = attr->ia_valid; if ((ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) && exfat_allow_set_time(sbi, inode)) { attr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET); } error = setattr_prepare(dentry, attr); attr->ia_valid = ia_valid; if (error) goto out; if (((attr->ia_valid & ATTR_UID) && !uid_eq(attr->ia_uid, sbi->options.fs_uid)) || ((attr->ia_valid & ATTR_GID) && !gid_eq(attr->ia_gid, sbi->options.fs_gid)) || ((attr->ia_valid & ATTR_MODE) && (attr->ia_mode & ~(S_IFREG | S_IFLNK | S_IFDIR | 0777)))) { error = -EPERM; goto out; } /* * We don't return -EPERM here. Yes, strange, but this is too * old behavior. */ if (attr->ia_valid & ATTR_MODE) { if (exfat_sanitize_mode(sbi, inode, &attr->ia_mode) < 0) attr->ia_valid &= ~ATTR_MODE; } if (attr->ia_valid & ATTR_SIZE) { error = exfat_block_truncate_page(inode, attr->ia_size); if (error) goto out; down_write(&EXFAT_I(inode)->truncate_lock); truncate_setsize(inode, attr->ia_size); exfat_truncate(inode, attr->ia_size); up_write(&EXFAT_I(inode)->truncate_lock); } setattr_copy(inode, attr); mark_inode_dirty(inode); out: return error; } const struct file_operations exfat_file_operations = { .llseek = generic_file_llseek, .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, .fsync = generic_file_fsync, .splice_read = generic_file_splice_read, }; const struct inode_operations exfat_file_inode_operations = { .setattr = exfat_setattr, .getattr = exfat_getattr, }; No newline at end of file Loading
fs/exfat/fatent.c 0 → 100644 +463 −0 Original line number Diff line number Diff line // SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. */ #include <linux/slab.h> #include <asm/unaligned.h> #include <linux/buffer_head.h> #include "exfat_raw.h" #include "exfat_fs.h" static int exfat_mirror_bh(struct super_block *sb, sector_t sec, struct buffer_head *bh) { struct buffer_head *c_bh; struct exfat_sb_info *sbi = EXFAT_SB(sb); sector_t sec2; int err = 0; if (sbi->FAT2_start_sector != sbi->FAT1_start_sector) { sec2 = sec - sbi->FAT1_start_sector + sbi->FAT2_start_sector; c_bh = sb_getblk(sb, sec2); if (!c_bh) return -ENOMEM; memcpy(c_bh->b_data, bh->b_data, sb->s_blocksize); set_buffer_uptodate(c_bh); mark_buffer_dirty(c_bh); if (sb->s_flags & SB_SYNCHRONOUS) err = sync_dirty_buffer(c_bh); brelse(c_bh); } return err; } static int __exfat_ent_get(struct super_block *sb, unsigned int loc, unsigned int *content) { unsigned int off; sector_t sec; struct buffer_head *bh; sec = FAT_ENT_OFFSET_SECTOR(sb, loc); off = FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc); bh = sb_bread(sb, sec); if (!bh) return -EIO; *content = le32_to_cpu(*(__le32 *)(&bh->b_data[off])); /* remap reserved clusters to simplify code */ if (*content > EXFAT_BAD_CLUSTER) *content = EXFAT_EOF_CLUSTER; brelse(bh); return 0; } int exfat_ent_set(struct super_block *sb, unsigned int loc, unsigned int content) { unsigned int off; sector_t sec; __le32 *fat_entry; struct buffer_head *bh; sec = FAT_ENT_OFFSET_SECTOR(sb, loc); off = FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc); bh = sb_bread(sb, sec); if (!bh) return -EIO; fat_entry = (__le32 *)&(bh->b_data[off]); *fat_entry = cpu_to_le32(content); exfat_update_bh(sb, bh, sb->s_flags & SB_SYNCHRONOUS); exfat_mirror_bh(sb, sec, bh); brelse(bh); return 0; } static inline bool is_valid_cluster(struct exfat_sb_info *sbi, unsigned int clus) { if (clus < EXFAT_FIRST_CLUSTER || sbi->num_clusters <= clus) return false; return true; } int exfat_ent_get(struct super_block *sb, unsigned int loc, unsigned int *content) { struct exfat_sb_info *sbi = EXFAT_SB(sb); int err; if (!is_valid_cluster(sbi, loc)) { exfat_fs_error(sb, "invalid access to FAT (entry 0x%08x)", loc); return -EIO; } err = __exfat_ent_get(sb, loc, content); if (err) { exfat_fs_error(sb, "failed to access to FAT (entry 0x%08x, err:%d)", loc, err); return err; } if (*content == EXFAT_FREE_CLUSTER) { exfat_fs_error(sb, "invalid access to FAT free cluster (entry 0x%08x)", loc); return -EIO; } if (*content == EXFAT_BAD_CLUSTER) { exfat_fs_error(sb, "invalid access to FAT bad cluster (entry 0x%08x)", loc); return -EIO; } if (*content != EXFAT_EOF_CLUSTER && !is_valid_cluster(sbi, *content)) { exfat_fs_error(sb, "invalid access to FAT (entry 0x%08x) bogus content (0x%08x)", loc, *content); return -EIO; } return 0; } int exfat_chain_cont_cluster(struct super_block *sb, unsigned int chain, unsigned int len) { if (!len) return 0; while (len > 1) { if (exfat_ent_set(sb, chain, chain + 1)) return -EIO; chain++; len--; } if (exfat_ent_set(sb, chain, EXFAT_EOF_CLUSTER)) return -EIO; return 0; } int exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain) { unsigned int num_clusters = 0; unsigned int clu; struct super_block *sb = inode->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); /* invalid cluster number */ if (p_chain->dir == EXFAT_FREE_CLUSTER || p_chain->dir == EXFAT_EOF_CLUSTER || p_chain->dir < EXFAT_FIRST_CLUSTER) return 0; /* no cluster to truncate */ if (p_chain->size == 0) return 0; /* check cluster validation */ if (p_chain->dir < 2 && p_chain->dir >= sbi->num_clusters) { exfat_msg(sb, KERN_ERR, "invalid start cluster (%u)", p_chain->dir); return -EIO; } set_bit(EXFAT_SB_DIRTY, &sbi->s_state); clu = p_chain->dir; if (p_chain->flags == ALLOC_NO_FAT_CHAIN) { do { exfat_clear_bitmap(inode, clu); clu++; num_clusters++; } while (num_clusters < p_chain->size); } else { do { exfat_clear_bitmap(inode, clu); if (exfat_get_next_cluster(sb, &clu)) goto dec_used_clus; num_clusters++; } while (clu != EXFAT_EOF_CLUSTER); } dec_used_clus: sbi->used_clusters -= num_clusters; return 0; } int exfat_find_last_cluster(struct super_block *sb, struct exfat_chain *p_chain, unsigned int *ret_clu) { unsigned int clu, next; unsigned int count = 0; next = p_chain->dir; if (p_chain->flags == ALLOC_NO_FAT_CHAIN) { *ret_clu = next + p_chain->size - 1; return 0; } do { count++; clu = next; if (exfat_ent_get(sb, clu, &next)) return -EIO; } while (next != EXFAT_EOF_CLUSTER); if (p_chain->size != count) { exfat_fs_error(sb, "bogus directory size (clus : ondisk(%d) != counted(%d))", p_chain->size, count); return -EIO; } *ret_clu = clu; return 0; } static inline int exfat_sync_bhs(struct buffer_head **bhs, int nr_bhs) { int i, err = 0; for (i = 0; i < nr_bhs; i++) write_dirty_buffer(bhs[i], 0); for (i = 0; i < nr_bhs; i++) { wait_on_buffer(bhs[i]); if (!err && !buffer_uptodate(bhs[i])) err = -EIO; } return err; } int exfat_zeroed_cluster(struct inode *dir, unsigned int clu) { struct super_block *sb = dir->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); struct buffer_head *bhs[MAX_BUF_PER_PAGE]; int nr_bhs = MAX_BUF_PER_PAGE; sector_t blknr, last_blknr; int err, i, n; blknr = exfat_cluster_to_sector(sbi, clu); last_blknr = blknr + sbi->sect_per_clus; if (last_blknr > sbi->num_sectors && sbi->num_sectors > 0) { exfat_fs_error_ratelimit(sb, "%s: out of range(sect:%llu len:%u)", __func__, (unsigned long long)blknr, sbi->sect_per_clus); return -EIO; } /* Zeroing the unused blocks on this cluster */ n = 0; while (blknr < last_blknr) { bhs[n] = sb_getblk(sb, blknr); if (!bhs[n]) { err = -ENOMEM; goto release_bhs; } memset(bhs[n]->b_data, 0, sb->s_blocksize); exfat_update_bh(sb, bhs[n], 0); n++; blknr++; if (n == nr_bhs) { if (IS_DIRSYNC(dir)) { err = exfat_sync_bhs(bhs, n); if (err) goto release_bhs; } for (i = 0; i < n; i++) brelse(bhs[i]); n = 0; } } if (IS_DIRSYNC(dir)) { err = exfat_sync_bhs(bhs, n); if (err) goto release_bhs; } for (i = 0; i < n; i++) brelse(bhs[i]); return 0; release_bhs: exfat_msg(sb, KERN_ERR, "failed zeroed sect %llu\n", (unsigned long long)blknr); for (i = 0; i < n; i++) bforget(bhs[i]); return err; } int exfat_alloc_cluster(struct inode *inode, unsigned int num_alloc, struct exfat_chain *p_chain) { int ret = -ENOSPC; unsigned int num_clusters = 0, total_cnt; unsigned int hint_clu, new_clu, last_clu = EXFAT_EOF_CLUSTER; struct super_block *sb = inode->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); total_cnt = EXFAT_DATA_CLUSTER_COUNT(sbi); if (unlikely(total_cnt < sbi->used_clusters)) { exfat_fs_error_ratelimit(sb, "%s: invalid used clusters(t:%u,u:%u)\n", __func__, total_cnt, sbi->used_clusters); return -EIO; } if (num_alloc > total_cnt - sbi->used_clusters) return -ENOSPC; hint_clu = p_chain->dir; /* find new cluster */ if (hint_clu == EXFAT_EOF_CLUSTER) { if (sbi->clu_srch_ptr < EXFAT_FIRST_CLUSTER) { exfat_msg(sb, KERN_ERR, "sbi->clu_srch_ptr is invalid (%u)\n", sbi->clu_srch_ptr); sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER; } hint_clu = exfat_find_free_bitmap(sb, sbi->clu_srch_ptr); if (hint_clu == EXFAT_EOF_CLUSTER) return -ENOSPC; } /* check cluster validation */ if (hint_clu < EXFAT_FIRST_CLUSTER && hint_clu >= sbi->num_clusters) { exfat_msg(sb, KERN_ERR, "hint_cluster is invalid (%u)\n", hint_clu); hint_clu = EXFAT_FIRST_CLUSTER; if (p_chain->flags == ALLOC_NO_FAT_CHAIN) { if (exfat_chain_cont_cluster(sb, p_chain->dir, num_clusters)) return -EIO; p_chain->flags = ALLOC_FAT_CHAIN; } } set_bit(EXFAT_SB_DIRTY, &sbi->s_state); p_chain->dir = EXFAT_EOF_CLUSTER; while ((new_clu = exfat_find_free_bitmap(sb, hint_clu)) != EXFAT_EOF_CLUSTER) { if (new_clu != hint_clu && p_chain->flags == ALLOC_NO_FAT_CHAIN) { if (exfat_chain_cont_cluster(sb, p_chain->dir, num_clusters)) { ret = -EIO; goto free_cluster; } p_chain->flags = ALLOC_FAT_CHAIN; } /* update allocation bitmap */ if (exfat_set_bitmap(inode, new_clu)) { ret = -EIO; goto free_cluster; } num_clusters++; /* update FAT table */ if (p_chain->flags == ALLOC_FAT_CHAIN) { if (exfat_ent_set(sb, new_clu, EXFAT_EOF_CLUSTER)) { ret = -EIO; goto free_cluster; } } if (p_chain->dir == EXFAT_EOF_CLUSTER) { p_chain->dir = new_clu; } else if (p_chain->flags == ALLOC_FAT_CHAIN) { if (exfat_ent_set(sb, last_clu, new_clu)) { ret = -EIO; goto free_cluster; } } last_clu = new_clu; if (--num_alloc == 0) { sbi->clu_srch_ptr = hint_clu; sbi->used_clusters += num_clusters; p_chain->size += num_clusters; return 0; } hint_clu = new_clu + 1; if (hint_clu >= sbi->num_clusters) { hint_clu = EXFAT_FIRST_CLUSTER; if (p_chain->flags == ALLOC_NO_FAT_CHAIN) { if (exfat_chain_cont_cluster(sb, p_chain->dir, num_clusters)) { ret = -EIO; goto free_cluster; } p_chain->flags = ALLOC_FAT_CHAIN; } } } free_cluster: if (num_clusters) exfat_free_cluster(inode, p_chain); return ret; } int exfat_count_num_clusters(struct super_block *sb, struct exfat_chain *p_chain, unsigned int *ret_count) { unsigned int i, count; unsigned int clu; struct exfat_sb_info *sbi = EXFAT_SB(sb); if (!p_chain->dir || p_chain->dir == EXFAT_EOF_CLUSTER) { *ret_count = 0; return 0; } if (p_chain->flags == ALLOC_NO_FAT_CHAIN) { *ret_count = p_chain->size; return 0; } clu = p_chain->dir; count = 0; for (i = EXFAT_FIRST_CLUSTER; i < sbi->num_clusters; i++) { count++; if (exfat_ent_get(sb, clu, &clu)) return -EIO; if (clu == EXFAT_EOF_CLUSTER) break; } *ret_count = count; return 0; } No newline at end of file
fs/exfat/file.c 0 → 100644 +360 −0 Original line number Diff line number Diff line // SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. */ #include <linux/slab.h> #include <linux/cred.h> #include <linux/buffer_head.h> #include "exfat_raw.h" #include "exfat_fs.h" static int exfat_cont_expand(struct inode *inode, loff_t size) { struct address_space *mapping = inode->i_mapping; loff_t start = i_size_read(inode), count = size - i_size_read(inode); int err, err2; err = generic_cont_expand_simple(inode, size); if (err) return err; inode->i_ctime = inode->i_mtime = current_time(inode); mark_inode_dirty(inode); if (!IS_SYNC(inode)) return 0; err = filemap_fdatawrite_range(mapping, start, start + count - 1); err2 = sync_mapping_buffers(mapping); if (!err) err = err2; err2 = write_inode_now(inode, 1); if (!err) err = err2; if (err) return err; return filemap_fdatawait_range(mapping, start, start + count - 1); } static bool exfat_allow_set_time(struct exfat_sb_info *sbi, struct inode *inode) { mode_t allow_utime = sbi->options.allow_utime; if (!uid_eq(current_fsuid(), inode->i_uid)) { if (in_group_p(inode->i_gid)) allow_utime >>= 3; if (allow_utime & MAY_WRITE) return true; } /* use a default check */ return false; } static int exfat_sanitize_mode(const struct exfat_sb_info *sbi, struct inode *inode, umode_t *mode_ptr) { mode_t i_mode, mask, perm; i_mode = inode->i_mode; mask = (S_ISREG(i_mode) || S_ISLNK(i_mode)) ? sbi->options.fs_fmask : sbi->options.fs_dmask; perm = *mode_ptr & ~(S_IFMT | mask); /* Of the r and x bits, all (subject to umask) must be present.*/ if ((perm & 0555) != (i_mode & 0555)) return -EPERM; if (exfat_mode_can_hold_ro(inode)) { /* * Of the w bits, either all (subject to umask) or none must * be present. */ if ((perm & 0222) && ((perm & 0222) != (0222 & ~mask))) return -EPERM; } else { /* * If exfat_mode_can_hold_ro(inode) is false, can't change * w bits. */ if ((perm & 0222) != (0222 & ~mask)) return -EPERM; } *mode_ptr &= S_IFMT | perm; return 0; } /* resize the file length */ int __exfat_truncate(struct inode *inode, loff_t new_size) { unsigned int num_clusters_new, num_clusters_phys; unsigned int last_clu = EXFAT_FREE_CLUSTER; struct exfat_chain clu; struct exfat_dentry *ep, *ep2; 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_entry_set_cache *es = NULL; int evict = (ei->dir.dir == DIR_DELETED) ? 1 : 0; /* check if the given file ID is opened */ if (ei->type != TYPE_FILE && ei->type != TYPE_DIR) return -EPERM; exfat_set_vol_flags(sb, VOL_DIRTY); num_clusters_new = EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi); num_clusters_phys = EXFAT_B_TO_CLU_ROUND_UP(EXFAT_I(inode)->i_size_ondisk, sbi); exfat_chain_set(&clu, ei->start_clu, num_clusters_phys, ei->flags); if (new_size > 0) { /* * Truncate FAT chain num_clusters after the first cluster * num_clusters = min(new, phys); */ unsigned int num_clusters = min(num_clusters_new, num_clusters_phys); /* * Follow FAT chain * (defensive coding - works fine even with corrupted FAT table */ if (clu.flags == ALLOC_NO_FAT_CHAIN) { clu.dir += num_clusters; clu.size -= num_clusters; } else { while (num_clusters > 0) { last_clu = clu.dir; if (exfat_get_next_cluster(sb, &(clu.dir))) return -EIO; num_clusters--; clu.size--; } } } else { ei->flags = ALLOC_NO_FAT_CHAIN; ei->start_clu = EXFAT_EOF_CLUSTER; } i_size_write(inode, new_size); if (ei->type == TYPE_FILE) ei->attr |= ATTR_ARCHIVE; /* update the directory entry */ if (!evict) { struct timespec64 ts; es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES, &ep); if (!es) return -EIO; ep2 = ep + 1; ts = current_time(inode); exfat_set_entry_time(sbi, &ts, &ep->dentry.file.modify_tz, &ep->dentry.file.modify_time, &ep->dentry.file.modify_date, &ep->dentry.file.modify_time_ms); ep->dentry.file.attr = cpu_to_le16(ei->attr); /* File size should be zero if there is no cluster allocated */ if (ei->start_clu == EXFAT_EOF_CLUSTER) { ep->dentry.stream.valid_size = 0; ep->dentry.stream.size = 0; } else { ep->dentry.stream.valid_size = cpu_to_le64(new_size); ep->dentry.stream.size = ep->dentry.stream.valid_size; } if (new_size == 0) { /* Any directory can not be truncated to zero */ WARN_ON(ei->type != TYPE_FILE); ep2->dentry.stream.flags = ALLOC_FAT_CHAIN; ep2->dentry.stream.start_clu = EXFAT_FREE_CLUSTER; } if (exfat_update_dir_chksum_with_entry_set(sb, es, inode_needs_sync(inode))) return -EIO; kfree(es); } /* cut off from the FAT chain */ if (ei->flags == ALLOC_FAT_CHAIN && last_clu != EXFAT_FREE_CLUSTER && last_clu != EXFAT_EOF_CLUSTER) { if (exfat_ent_set(sb, last_clu, EXFAT_EOF_CLUSTER)) return -EIO; } /* invalidate cache and free the clusters */ /* clear exfat cache */ exfat_cache_inval_inode(inode); /* hint information */ ei->hint_bmap.off = EXFAT_EOF_CLUSTER; ei->hint_bmap.clu = EXFAT_EOF_CLUSTER; if (ei->rwoffset > new_size) ei->rwoffset = new_size; /* hint_stat will be used if this is directory. */ ei->hint_stat.eidx = 0; ei->hint_stat.clu = ei->start_clu; ei->hint_femp.eidx = EXFAT_HINT_NONE; /* free the clusters */ if (exfat_free_cluster(inode, &clu)) return -EIO; exfat_set_vol_flags(sb, VOL_CLEAN); return 0; } void exfat_truncate(struct inode *inode, loff_t size) { struct super_block *sb = inode->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); unsigned int blocksize = 1 << inode->i_blkbits; loff_t aligned_size; int err; mutex_lock(&sbi->s_lock); if (EXFAT_I(inode)->start_clu == 0) { /* * Empty start_clu != ~0 (not allocated) */ exfat_fs_error(sb, "tried to truncate zeroed cluster."); goto write_size; } err = __exfat_truncate(inode, i_size_read(inode)); if (err) goto write_size; inode->i_ctime = inode->i_mtime = current_time(inode); if (IS_DIRSYNC(inode)) exfat_sync_inode(inode); else mark_inode_dirty(inode); inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) & ~(sbi->cluster_size - 1)) >> inode->i_blkbits; write_size: aligned_size = i_size_read(inode); if (aligned_size & (blocksize - 1)) { aligned_size |= (blocksize - 1); aligned_size++; } if (EXFAT_I(inode)->i_size_ondisk > i_size_read(inode)) EXFAT_I(inode)->i_size_ondisk = aligned_size; if (EXFAT_I(inode)->i_size_aligned > i_size_read(inode)) EXFAT_I(inode)->i_size_aligned = aligned_size; mutex_unlock(&sbi->s_lock); } int exfat_getattr(const struct path *path, struct kstat *stat, unsigned int request_mask, unsigned int query_flags) { struct inode *inode = d_backing_inode(path->dentry); struct exfat_inode_info *ei = EXFAT_I(inode); generic_fillattr(inode, stat); stat->result_mask |= STATX_BTIME; stat->btime.tv_sec = ei->i_crtime.tv_sec; stat->btime.tv_nsec = ei->i_crtime.tv_nsec; stat->blksize = EXFAT_SB(inode->i_sb)->cluster_size; return 0; } int exfat_setattr(struct dentry *dentry, struct iattr *attr) { struct exfat_sb_info *sbi = EXFAT_SB(dentry->d_sb); struct inode *inode = dentry->d_inode; unsigned int ia_valid; int error; if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size > i_size_read(inode)) { error = exfat_cont_expand(inode, attr->ia_size); if (error || attr->ia_valid == ATTR_SIZE) return error; attr->ia_valid &= ~ATTR_SIZE; } /* Check for setting the inode time. */ ia_valid = attr->ia_valid; if ((ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) && exfat_allow_set_time(sbi, inode)) { attr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET); } error = setattr_prepare(dentry, attr); attr->ia_valid = ia_valid; if (error) goto out; if (((attr->ia_valid & ATTR_UID) && !uid_eq(attr->ia_uid, sbi->options.fs_uid)) || ((attr->ia_valid & ATTR_GID) && !gid_eq(attr->ia_gid, sbi->options.fs_gid)) || ((attr->ia_valid & ATTR_MODE) && (attr->ia_mode & ~(S_IFREG | S_IFLNK | S_IFDIR | 0777)))) { error = -EPERM; goto out; } /* * We don't return -EPERM here. Yes, strange, but this is too * old behavior. */ if (attr->ia_valid & ATTR_MODE) { if (exfat_sanitize_mode(sbi, inode, &attr->ia_mode) < 0) attr->ia_valid &= ~ATTR_MODE; } if (attr->ia_valid & ATTR_SIZE) { error = exfat_block_truncate_page(inode, attr->ia_size); if (error) goto out; down_write(&EXFAT_I(inode)->truncate_lock); truncate_setsize(inode, attr->ia_size); exfat_truncate(inode, attr->ia_size); up_write(&EXFAT_I(inode)->truncate_lock); } setattr_copy(inode, attr); mark_inode_dirty(inode); out: return error; } const struct file_operations exfat_file_operations = { .llseek = generic_file_llseek, .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, .fsync = generic_file_fsync, .splice_read = generic_file_splice_read, }; const struct inode_operations exfat_file_inode_operations = { .setattr = exfat_setattr, .getattr = exfat_getattr, }; No newline at end of file