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author | Namjae Jeon <namjae.jeon@samsung.com> | 2020-03-02 15:21:34 +0900 |
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committer | Al Viro <viro@zeniv.linux.org.uk> | 2020-03-05 21:00:40 -0500 |
commit | 5f2aa075070cf5b2e6aae011d5a3390408d7d913 (patch) | |
tree | a7d03f12e7037ac0cb7220e9944087fa77ff1d16 /fs/exfat/inode.c | |
parent | 719c1e1829166da399903b13da6dcc5344e73449 (diff) | |
download | linux-5f2aa075070cf5b2e6aae011d5a3390408d7d913.tar.bz2 |
exfat: add inode operations
This adds the implementation of inode operations for exfat.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/exfat/inode.c')
-rw-r--r-- | fs/exfat/inode.c | 671 |
1 files changed, 671 insertions, 0 deletions
diff --git a/fs/exfat/inode.c b/fs/exfat/inode.c new file mode 100644 index 000000000000..06887492f54b --- /dev/null +++ b/fs/exfat/inode.c @@ -0,0 +1,671 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. + */ + +#include <linux/init.h> +#include <linux/buffer_head.h> +#include <linux/mpage.h> +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <linux/time.h> +#include <linux/writeback.h> +#include <linux/uio.h> +#include <linux/random.h> +#include <linux/iversion.h> + +#include "exfat_raw.h" +#include "exfat_fs.h" + +static int __exfat_write_inode(struct inode *inode, int sync) +{ + int ret = -EIO; + unsigned long long on_disk_size; + struct exfat_dentry *ep, *ep2; + struct exfat_entry_set_cache *es = NULL; + struct super_block *sb = inode->i_sb; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct exfat_inode_info *ei = EXFAT_I(inode); + bool is_dir = (ei->type == TYPE_DIR) ? true : false; + + if (inode->i_ino == EXFAT_ROOT_INO) + return 0; + + /* + * If the indode is already unlinked, there is no need for updating it. + */ + if (ei->dir.dir == DIR_DELETED) + return 0; + + if (is_dir && ei->dir.dir == sbi->root_dir && ei->entry == -1) + return 0; + + exfat_set_vol_flags(sb, VOL_DIRTY); + + /* get the directory entry of given file or directory */ + es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES, + &ep); + if (!es) + return -EIO; + ep2 = ep + 1; + + ep->dentry.file.attr = cpu_to_le16(exfat_make_attr(inode)); + + /* set FILE_INFO structure using the acquired struct exfat_dentry */ + exfat_set_entry_time(sbi, &ei->i_crtime, + &ep->dentry.file.create_tz, + &ep->dentry.file.create_time, + &ep->dentry.file.create_date, + &ep->dentry.file.create_time_ms); + exfat_set_entry_time(sbi, &inode->i_mtime, + &ep->dentry.file.modify_tz, + &ep->dentry.file.modify_time, + &ep->dentry.file.modify_date, + &ep->dentry.file.modify_time_ms); + exfat_set_entry_time(sbi, &inode->i_atime, + &ep->dentry.file.access_tz, + &ep->dentry.file.access_time, + &ep->dentry.file.access_date, + NULL); + + /* File size should be zero if there is no cluster allocated */ + on_disk_size = i_size_read(inode); + + if (ei->start_clu == EXFAT_EOF_CLUSTER) + on_disk_size = 0; + + ep2->dentry.stream.valid_size = cpu_to_le64(on_disk_size); + ep2->dentry.stream.size = ep2->dentry.stream.valid_size; + + ret = exfat_update_dir_chksum_with_entry_set(sb, es, sync); + kfree(es); + return ret; +} + +int exfat_write_inode(struct inode *inode, struct writeback_control *wbc) +{ + int ret; + + mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock); + ret = __exfat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL); + mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock); + + return ret; +} + +void exfat_sync_inode(struct inode *inode) +{ + lockdep_assert_held(&EXFAT_SB(inode->i_sb)->s_lock); + __exfat_write_inode(inode, 1); +} + +/* + * Input: inode, (logical) clu_offset, target allocation area + * Output: errcode, cluster number + * *clu = (~0), if it's unable to allocate a new cluster + */ +static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset, + unsigned int *clu, int create) +{ + int ret, modified = false; + unsigned int last_clu; + struct exfat_chain new_clu; + struct exfat_dentry *ep; + struct exfat_entry_set_cache *es = NULL; + struct super_block *sb = inode->i_sb; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct exfat_inode_info *ei = EXFAT_I(inode); + unsigned int local_clu_offset = clu_offset; + unsigned int num_to_be_allocated = 0, num_clusters = 0; + + ei->rwoffset = EXFAT_CLU_TO_B(clu_offset, sbi); + + if (EXFAT_I(inode)->i_size_ondisk > 0) + num_clusters = + EXFAT_B_TO_CLU_ROUND_UP(EXFAT_I(inode)->i_size_ondisk, + sbi); + + if (clu_offset >= num_clusters) + num_to_be_allocated = clu_offset - num_clusters + 1; + + if (!create && (num_to_be_allocated > 0)) { + *clu = EXFAT_EOF_CLUSTER; + return 0; + } + + *clu = last_clu = ei->start_clu; + + if (ei->flags == ALLOC_NO_FAT_CHAIN) { + if (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) { + last_clu += clu_offset - 1; + + if (clu_offset == num_clusters) + *clu = EXFAT_EOF_CLUSTER; + else + *clu += clu_offset; + } + } else if (ei->type == TYPE_FILE) { + unsigned int fclus = 0; + int err = exfat_get_cluster(inode, clu_offset, + &fclus, clu, &last_clu, 1); + if (err) + return -EIO; + + clu_offset -= fclus; + } else { + /* hint information */ + if (clu_offset > 0 && ei->hint_bmap.off != EXFAT_EOF_CLUSTER && + ei->hint_bmap.off > 0 && clu_offset >= ei->hint_bmap.off) { + clu_offset -= ei->hint_bmap.off; + /* hint_bmap.clu should be valid */ + WARN_ON(ei->hint_bmap.clu < 2); + *clu = ei->hint_bmap.clu; + } + + while (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) { + last_clu = *clu; + if (exfat_get_next_cluster(sb, clu)) + return -EIO; + clu_offset--; + } + } + + if (*clu == EXFAT_EOF_CLUSTER) { + exfat_set_vol_flags(sb, VOL_DIRTY); + + new_clu.dir = (last_clu == EXFAT_EOF_CLUSTER) ? + EXFAT_EOF_CLUSTER : last_clu + 1; + new_clu.size = 0; + new_clu.flags = ei->flags; + + /* allocate a cluster */ + if (num_to_be_allocated < 1) { + /* Broken FAT (i_sze > allocated FAT) */ + exfat_fs_error(sb, "broken FAT chain."); + return -EIO; + } + + ret = exfat_alloc_cluster(inode, num_to_be_allocated, &new_clu); + if (ret) + return ret; + + if (new_clu.dir == EXFAT_EOF_CLUSTER || + new_clu.dir == EXFAT_FREE_CLUSTER) { + exfat_fs_error(sb, + "bogus cluster new allocated (last_clu : %u, new_clu : %u)", + last_clu, new_clu.dir); + return -EIO; + } + + /* append to the FAT chain */ + if (last_clu == EXFAT_EOF_CLUSTER) { + if (new_clu.flags == ALLOC_FAT_CHAIN) + ei->flags = ALLOC_FAT_CHAIN; + ei->start_clu = new_clu.dir; + modified = true; + } else { + if (new_clu.flags != ei->flags) { + /* no-fat-chain bit is disabled, + * so fat-chain should be synced with + * alloc-bitmap + */ + exfat_chain_cont_cluster(sb, ei->start_clu, + num_clusters); + ei->flags = ALLOC_FAT_CHAIN; + modified = true; + } + if (new_clu.flags == ALLOC_FAT_CHAIN) + if (exfat_ent_set(sb, last_clu, new_clu.dir)) + return -EIO; + } + + num_clusters += num_to_be_allocated; + *clu = new_clu.dir; + + if (ei->dir.dir != DIR_DELETED) { + es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, + ES_ALL_ENTRIES, &ep); + if (!es) + return -EIO; + /* get stream entry */ + ep++; + + /* update directory entry */ + if (modified) { + if (ep->dentry.stream.flags != ei->flags) + ep->dentry.stream.flags = ei->flags; + + if (le32_to_cpu(ep->dentry.stream.start_clu) != + ei->start_clu) + ep->dentry.stream.start_clu = + cpu_to_le32(ei->start_clu); + + ep->dentry.stream.valid_size = + cpu_to_le64(i_size_read(inode)); + ep->dentry.stream.size = + ep->dentry.stream.valid_size; + } + + if (exfat_update_dir_chksum_with_entry_set(sb, es, + inode_needs_sync(inode))) + return -EIO; + kfree(es); + + } /* end of if != DIR_DELETED */ + + inode->i_blocks += + num_to_be_allocated << sbi->sect_per_clus_bits; + + /* + * Move *clu pointer along FAT chains (hole care) because the + * caller of this function expect *clu to be the last cluster. + * This only works when num_to_be_allocated >= 2, + * *clu = (the first cluster of the allocated chain) => + * (the last cluster of ...) + */ + if (ei->flags == ALLOC_NO_FAT_CHAIN) { + *clu += num_to_be_allocated - 1; + } else { + while (num_to_be_allocated > 1) { + if (exfat_get_next_cluster(sb, clu)) + return -EIO; + num_to_be_allocated--; + } + } + + } + + /* hint information */ + ei->hint_bmap.off = local_clu_offset; + ei->hint_bmap.clu = *clu; + + return 0; +} + +static int exfat_map_new_buffer(struct exfat_inode_info *ei, + struct buffer_head *bh, loff_t pos) +{ + if (buffer_delay(bh) && pos > ei->i_size_aligned) + return -EIO; + set_buffer_new(bh); + + /* + * Adjust i_size_aligned if i_size_ondisk is bigger than it. + */ + if (ei->i_size_ondisk > ei->i_size_aligned) + ei->i_size_aligned = ei->i_size_ondisk; + return 0; +} + +static int exfat_get_block(struct inode *inode, sector_t iblock, + struct buffer_head *bh_result, int create) +{ + struct exfat_inode_info *ei = EXFAT_I(inode); + struct super_block *sb = inode->i_sb; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits; + int err = 0; + unsigned long mapped_blocks = 0; + unsigned int cluster, sec_offset; + sector_t last_block; + sector_t phys = 0; + loff_t pos; + + mutex_lock(&sbi->s_lock); + last_block = EXFAT_B_TO_BLK_ROUND_UP(i_size_read(inode), sb); + if (iblock >= last_block && !create) + goto done; + + /* Is this block already allocated? */ + err = exfat_map_cluster(inode, iblock >> sbi->sect_per_clus_bits, + &cluster, create); + if (err) { + if (err != -ENOSPC) + exfat_fs_error_ratelimit(sb, + "failed to bmap (inode : %p iblock : %llu, err : %d)", + inode, (unsigned long long)iblock, err); + goto unlock_ret; + } + + if (cluster == EXFAT_EOF_CLUSTER) + goto done; + + /* sector offset in cluster */ + sec_offset = iblock & (sbi->sect_per_clus - 1); + + phys = exfat_cluster_to_sector(sbi, cluster) + sec_offset; + mapped_blocks = sbi->sect_per_clus - sec_offset; + max_blocks = min(mapped_blocks, max_blocks); + + /* Treat newly added block / cluster */ + if (iblock < last_block) + create = 0; + + if (create || buffer_delay(bh_result)) { + pos = EXFAT_BLK_TO_B((iblock + 1), sb); + if (ei->i_size_ondisk < pos) + ei->i_size_ondisk = pos; + } + + if (create) { + err = exfat_map_new_buffer(ei, bh_result, pos); + if (err) { + exfat_fs_error(sb, + "requested for bmap out of range(pos : (%llu) > i_size_aligned(%llu)\n", + pos, ei->i_size_aligned); + goto unlock_ret; + } + } + + if (buffer_delay(bh_result)) + clear_buffer_delay(bh_result); + map_bh(bh_result, sb, phys); +done: + bh_result->b_size = EXFAT_BLK_TO_B(max_blocks, sb); +unlock_ret: + mutex_unlock(&sbi->s_lock); + return err; +} + +static int exfat_readpage(struct file *file, struct page *page) +{ + return mpage_readpage(page, exfat_get_block); +} + +static int exfat_readpages(struct file *file, struct address_space *mapping, + struct list_head *pages, unsigned int nr_pages) +{ + return mpage_readpages(mapping, pages, nr_pages, exfat_get_block); +} + +static int exfat_writepage(struct page *page, struct writeback_control *wbc) +{ + return block_write_full_page(page, exfat_get_block, wbc); +} + +static int exfat_writepages(struct address_space *mapping, + struct writeback_control *wbc) +{ + return mpage_writepages(mapping, wbc, exfat_get_block); +} + +static void exfat_write_failed(struct address_space *mapping, loff_t to) +{ + struct inode *inode = mapping->host; + + if (to > i_size_read(inode)) { + truncate_pagecache(inode, i_size_read(inode)); + exfat_truncate(inode, EXFAT_I(inode)->i_size_aligned); + } +} + +static int exfat_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned int len, unsigned int flags, + struct page **pagep, void **fsdata) +{ + int ret; + + *pagep = NULL; + ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata, + exfat_get_block, + &EXFAT_I(mapping->host)->i_size_ondisk); + + if (ret < 0) + exfat_write_failed(mapping, pos+len); + + return ret; +} + +static int exfat_write_end(struct file *file, struct address_space *mapping, + loff_t pos, unsigned int len, unsigned int copied, + struct page *pagep, void *fsdata) +{ + struct inode *inode = mapping->host; + struct exfat_inode_info *ei = EXFAT_I(inode); + int err; + + err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata); + + if (EXFAT_I(inode)->i_size_aligned < i_size_read(inode)) { + exfat_fs_error(inode->i_sb, + "invalid size(size(%llu) > aligned(%llu)\n", + i_size_read(inode), EXFAT_I(inode)->i_size_aligned); + return -EIO; + } + + if (err < len) + exfat_write_failed(mapping, pos+len); + + if (!(err < 0) && !(ei->attr & ATTR_ARCHIVE)) { + inode->i_mtime = inode->i_ctime = current_time(inode); + ei->attr |= ATTR_ARCHIVE; + mark_inode_dirty(inode); + } + + return err; +} + +static ssize_t exfat_direct_IO(struct kiocb *iocb, struct iov_iter *iter) +{ + struct address_space *mapping = iocb->ki_filp->f_mapping; + struct inode *inode = mapping->host; + loff_t size = iocb->ki_pos + iov_iter_count(iter); + int rw = iov_iter_rw(iter); + ssize_t ret; + + if (rw == WRITE) { + /* + * FIXME: blockdev_direct_IO() doesn't use ->write_begin(), + * so we need to update the ->i_size_aligned to block boundary. + * + * But we must fill the remaining area or hole by nul for + * updating ->i_size_aligned + * + * Return 0, and fallback to normal buffered write. + */ + if (EXFAT_I(inode)->i_size_aligned < size) + return 0; + } + + /* + * Need to use the DIO_LOCKING for avoiding the race + * condition of exfat_get_block() and ->truncate(). + */ + ret = blockdev_direct_IO(iocb, inode, iter, exfat_get_block); + if (ret < 0 && (rw & WRITE)) + exfat_write_failed(mapping, size); + return ret; +} + +static sector_t exfat_aop_bmap(struct address_space *mapping, sector_t block) +{ + sector_t blocknr; + + /* exfat_get_cluster() assumes the requested blocknr isn't truncated. */ + down_read(&EXFAT_I(mapping->host)->truncate_lock); + blocknr = generic_block_bmap(mapping, block, exfat_get_block); + up_read(&EXFAT_I(mapping->host)->truncate_lock); + return blocknr; +} + +/* + * exfat_block_truncate_page() zeroes out a mapping from file offset `from' + * up to the end of the block which corresponds to `from'. + * This is required during truncate to physically zeroout the tail end + * of that block so it doesn't yield old data if the file is later grown. + * Also, avoid causing failure from fsx for cases of "data past EOF" + */ +int exfat_block_truncate_page(struct inode *inode, loff_t from) +{ + return block_truncate_page(inode->i_mapping, from, exfat_get_block); +} + +static const struct address_space_operations exfat_aops = { + .readpage = exfat_readpage, + .readpages = exfat_readpages, + .writepage = exfat_writepage, + .writepages = exfat_writepages, + .write_begin = exfat_write_begin, + .write_end = exfat_write_end, + .direct_IO = exfat_direct_IO, + .bmap = exfat_aop_bmap +}; + +static inline unsigned long exfat_hash(loff_t i_pos) +{ + return hash_32(i_pos, EXFAT_HASH_BITS); +} + +void exfat_hash_inode(struct inode *inode, loff_t i_pos) +{ + struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb); + struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos); + + spin_lock(&sbi->inode_hash_lock); + EXFAT_I(inode)->i_pos = i_pos; + hlist_add_head(&EXFAT_I(inode)->i_hash_fat, head); + spin_unlock(&sbi->inode_hash_lock); +} + +void exfat_unhash_inode(struct inode *inode) +{ + struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb); + + spin_lock(&sbi->inode_hash_lock); + hlist_del_init(&EXFAT_I(inode)->i_hash_fat); + EXFAT_I(inode)->i_pos = 0; + spin_unlock(&sbi->inode_hash_lock); +} + +struct inode *exfat_iget(struct super_block *sb, loff_t i_pos) +{ + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct exfat_inode_info *info; + struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos); + struct inode *inode = NULL; + + spin_lock(&sbi->inode_hash_lock); + hlist_for_each_entry(info, head, i_hash_fat) { + WARN_ON(info->vfs_inode.i_sb != sb); + + if (i_pos != info->i_pos) + continue; + inode = igrab(&info->vfs_inode); + if (inode) + break; + } + spin_unlock(&sbi->inode_hash_lock); + return inode; +} + +/* doesn't deal with root inode */ +static int exfat_fill_inode(struct inode *inode, struct exfat_dir_entry *info) +{ + struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb); + struct exfat_inode_info *ei = EXFAT_I(inode); + loff_t size = info->size; + + memcpy(&ei->dir, &info->dir, sizeof(struct exfat_chain)); + ei->entry = info->entry; + ei->attr = info->attr; + ei->start_clu = info->start_clu; + ei->flags = info->flags; + ei->type = info->type; + + ei->version = 0; + ei->hint_stat.eidx = 0; + ei->hint_stat.clu = info->start_clu; + ei->hint_femp.eidx = EXFAT_HINT_NONE; + ei->rwoffset = 0; + ei->hint_bmap.off = EXFAT_EOF_CLUSTER; + ei->i_pos = 0; + + inode->i_uid = sbi->options.fs_uid; + inode->i_gid = sbi->options.fs_gid; + inode_inc_iversion(inode); + inode->i_generation = prandom_u32(); + + if (info->attr & ATTR_SUBDIR) { /* directory */ + inode->i_generation &= ~1; + inode->i_mode = exfat_make_mode(sbi, info->attr, 0777); + inode->i_op = &exfat_dir_inode_operations; + inode->i_fop = &exfat_dir_operations; + set_nlink(inode, info->num_subdirs); + } else { /* regular file */ + inode->i_generation |= 1; + inode->i_mode = exfat_make_mode(sbi, info->attr, 0777); + inode->i_op = &exfat_file_inode_operations; + inode->i_fop = &exfat_file_operations; + inode->i_mapping->a_ops = &exfat_aops; + inode->i_mapping->nrpages = 0; + } + + i_size_write(inode, size); + + /* ondisk and aligned size should be aligned with block size */ + if (size & (inode->i_sb->s_blocksize - 1)) { + size |= (inode->i_sb->s_blocksize - 1); + size++; + } + + ei->i_size_aligned = size; + ei->i_size_ondisk = size; + + exfat_save_attr(inode, info->attr); + + inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) & + ~(sbi->cluster_size - 1)) >> inode->i_blkbits; + inode->i_mtime = info->mtime; + inode->i_ctime = info->mtime; + ei->i_crtime = info->crtime; + inode->i_atime = info->atime; + + exfat_cache_init_inode(inode); + + return 0; +} + +struct inode *exfat_build_inode(struct super_block *sb, + struct exfat_dir_entry *info, loff_t i_pos) +{ + struct inode *inode; + int err; + + inode = exfat_iget(sb, i_pos); + if (inode) + goto out; + inode = new_inode(sb); + if (!inode) { + inode = ERR_PTR(-ENOMEM); + goto out; + } + inode->i_ino = iunique(sb, EXFAT_ROOT_INO); + inode_set_iversion(inode, 1); + err = exfat_fill_inode(inode, info); + if (err) { + iput(inode); + inode = ERR_PTR(err); + goto out; + } + exfat_hash_inode(inode, i_pos); + insert_inode_hash(inode); +out: + return inode; +} + +void exfat_evict_inode(struct inode *inode) +{ + truncate_inode_pages(&inode->i_data, 0); + + if (!inode->i_nlink) { + i_size_write(inode, 0); + mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock); + __exfat_truncate(inode, 0); + mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock); + } + + invalidate_inode_buffers(inode); + clear_inode(inode); + exfat_cache_inval_inode(inode); + exfat_unhash_inode(inode); +} |