From 943af1fdacfebe4ff13430655abc460a5e1072f7 Mon Sep 17 00:00:00 2001 From: Tetsuhiro Kohada Date: Wed, 20 May 2020 16:56:41 +0900 Subject: [Backport 943af1fdacfe] exfat: optimize dir-cache Optimize directory access based on exfat_entry_set_cache. - Hold bh instead of copied d-entry. - Modify bh->data directly instead of the copied d-entry. - Write back the retained bh instead of rescanning the d-entry-set. And - Remove unused cache related definitions. Signed-off-by: Tetsuhiro Kohada Reviewed-by: Sungjong Seo Signed-off-by: Namjae Jeon --- src/dir.c | 197 +++++++++++++++++--------------------------- src/exfat_fs.h | 27 +++--- src/file.c | 15 ++-- src/inode.c | 53 +++++------- src/namei.c | 14 ++-- 5 files changed, 124 insertions(+), 182 deletions(-) diff --git a/src/dir.c b/src/dir.c index b5a237c33d50c02c632ec82627f78b4e70507d7a..2902d285bf20412af3a57b0e96a6768e49d6c5ac 100644 --- a/src/dir.c +++ b/src/dir.c @@ -32,35 +32,30 @@ static void exfat_get_uniname_from_ext_entry(struct super_block *sb, struct exfat_chain *p_dir, int entry, unsigned short *uniname) { int i; - struct exfat_dentry *ep; struct exfat_entry_set_cache *es; - es = exfat_get_dentry_set(sb, p_dir, entry, ES_ALL_ENTRIES, &ep); + es = exfat_get_dentry_set(sb, p_dir, entry, ES_ALL_ENTRIES); if (!es) return; - if (es->num_entries < 3) - goto free_es; - - ep += 2; - /* * First entry : file entry * Second entry : stream-extension entry * Third entry : first file-name entry * So, the index of first file-name dentry should start from 2. */ - for (i = 2; i < es->num_entries; i++, ep++) { + for (i = 2; i < es->num_entries; i++) { + struct exfat_dentry *ep = exfat_get_dentry_cached(es, i); + /* end of name entry */ if (exfat_get_entry_type(ep) != TYPE_EXTEND) - goto free_es; + break; exfat_extract_uni_name(ep, uniname); uniname += EXFAT_FILE_NAME_LEN; } -free_es: - kfree(es); + exfat_free_dentry_set(es, false); } /* read a directory entry from the opened directory */ @@ -590,62 +585,33 @@ int exfat_remove_entries(struct inode *inode, struct exfat_chain *p_dir, return 0; } -int exfat_update_dir_chksum_with_entry_set(struct super_block *sb, - struct exfat_entry_set_cache *es, int sync) +void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es) { - struct exfat_sb_info *sbi = EXFAT_SB(sb); - struct buffer_head *bh; - sector_t sec = es->sector; - unsigned int off = es->offset; - int chksum_type = CS_DIR_ENTRY, i, num_entries = es->num_entries; - unsigned int buf_off = (off - es->offset); - unsigned int remaining_byte_in_sector, copy_entries, clu; + int chksum_type = CS_DIR_ENTRY, i; unsigned short chksum = 0; + struct exfat_dentry *ep; - for (i = 0; i < num_entries; i++) { - chksum = exfat_calc_chksum_2byte(&es->entries[i], DENTRY_SIZE, - chksum, chksum_type); + for (i = 0; i < es->num_entries; i++) { + ep = exfat_get_dentry_cached(es, i); + chksum = exfat_calc_chksum_2byte(ep, DENTRY_SIZE, chksum, + chksum_type); chksum_type = CS_DEFAULT; } + ep = exfat_get_dentry_cached(es, 0); + ep->dentry.file.checksum = cpu_to_le16(chksum); + es->modified = true; +} - es->entries[0].dentry.file.checksum = cpu_to_le16(chksum); +void exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync) +{ + int i; - while (num_entries) { - /* write per sector base */ - remaining_byte_in_sector = (1 << sb->s_blocksize_bits) - off; - copy_entries = min_t(int, - EXFAT_B_TO_DEN(remaining_byte_in_sector), - num_entries); - bh = sb_bread(sb, sec); - if (!bh) - goto err_out; - memcpy(bh->b_data + off, - (unsigned char *)&es->entries[0] + buf_off, - EXFAT_DEN_TO_B(copy_entries)); - exfat_update_bh(sb, bh, sync); - brelse(bh); - num_entries -= copy_entries; - - if (num_entries) { - /* get next sector */ - if (exfat_is_last_sector_in_cluster(sbi, sec)) { - clu = exfat_sector_to_cluster(sbi, sec); - if (es->alloc_flag == ALLOC_NO_FAT_CHAIN) - clu++; - else if (exfat_get_next_cluster(sb, &clu)) - goto err_out; - sec = exfat_cluster_to_sector(sbi, clu); - } else { - sec++; - } - off = 0; - buf_off += EXFAT_DEN_TO_B(copy_entries); - } + for (i = 0; i < es->num_bh; i++) { + if (es->modified) + exfat_update_bh(es->sb, es->bh[i], sync); + brelse(es->bh[i]); } - - return 0; -err_out: - return -EIO; + kfree(es); } static int exfat_walk_fat_chain(struct super_block *sb, @@ -820,34 +786,40 @@ static bool exfat_validate_entry(unsigned int type, } } +struct exfat_dentry *exfat_get_dentry_cached( + struct exfat_entry_set_cache *es, int num) +{ + int off = es->start_off + num * DENTRY_SIZE; + struct buffer_head *bh = es->bh[EXFAT_B_TO_BLK(off, es->sb)]; + char *p = bh->b_data + EXFAT_BLK_OFFSET(off, es->sb); + + return (struct exfat_dentry *)p; +} + /* * Returns a set of dentries for a file or dir. * - * Note that this is a copy (dump) of dentries so that user should - * call write_entry_set() to apply changes made in this entry set - * to the real device. + * Note It provides a direct pointer to bh->data via exfat_get_dentry_cached(). + * User should call exfat_get_dentry_set() after setting 'modified' to apply + * changes made in this entry set to the real device. * * in: * sb+p_dir+entry: indicates a file/dir * type: specifies how many dentries should be included. - * out: - * file_ep: will point the first dentry(= file dentry) on success * return: * pointer of entry set on success, * NULL on failure. */ struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, - struct exfat_chain *p_dir, int entry, unsigned int type, - struct exfat_dentry **file_ep) + struct exfat_chain *p_dir, int entry, unsigned int type) { - int ret; + int ret, i, num_bh; unsigned int off, byte_offset, clu = 0; - unsigned int entry_type; sector_t sec; struct exfat_sb_info *sbi = EXFAT_SB(sb); struct exfat_entry_set_cache *es; - struct exfat_dentry *ep, *pos; - unsigned char num_entries; + struct exfat_dentry *ep; + int num_entries; enum exfat_validate_dentry_mode mode = ES_MODE_STARTED; struct buffer_head *bh; @@ -861,11 +833,18 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, if (ret) return NULL; + es = kzalloc(sizeof(*es), GFP_KERNEL); + if (!es) + return NULL; + es->sb = sb; + es->modified = false; + /* byte offset in cluster */ byte_offset = EXFAT_CLU_OFFSET(byte_offset, sbi); /* byte offset in sector */ off = EXFAT_BLK_OFFSET(byte_offset, sb); + es->start_off = off; /* sector offset in cluster */ sec = EXFAT_B_TO_BLK(byte_offset, sb); @@ -873,72 +852,46 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, bh = sb_bread(sb, sec); if (!bh) - return NULL; - - ep = (struct exfat_dentry *)(bh->b_data + off); - entry_type = exfat_get_entry_type(ep); + goto free_es; + es->bh[es->num_bh++] = bh; - if (entry_type != TYPE_FILE && entry_type != TYPE_DIR) - goto release_bh; + ep = exfat_get_dentry_cached(es, 0); + if (!exfat_validate_entry(exfat_get_entry_type(ep), &mode)) + goto free_es; num_entries = type == ES_ALL_ENTRIES ? ep->dentry.file.num_ext + 1 : type; - es = kmalloc(struct_size(es, entries, num_entries), GFP_KERNEL); - if (!es) - goto release_bh; - es->num_entries = num_entries; - es->sector = sec; - es->offset = off; - es->alloc_flag = p_dir->flags; - - pos = &es->entries[0]; - - while (num_entries) { - if (!exfat_validate_entry(exfat_get_entry_type(ep), &mode)) - goto free_es; - /* copy dentry */ - memcpy(pos, ep, sizeof(struct exfat_dentry)); - - if (--num_entries == 0) - break; - - if (((off + DENTRY_SIZE) & (sb->s_blocksize - 1)) < - (off & (sb->s_blocksize - 1))) { - /* get the next sector */ - if (exfat_is_last_sector_in_cluster(sbi, sec)) { - if (es->alloc_flag == ALLOC_NO_FAT_CHAIN) - clu++; - else if (exfat_get_next_cluster(sb, &clu)) - goto free_es; - sec = exfat_cluster_to_sector(sbi, clu); - } else { - sec++; - } - - brelse(bh); - bh = sb_bread(sb, sec); - if (!bh) + num_bh = EXFAT_B_TO_BLK_ROUND_UP(off + num_entries * DENTRY_SIZE, sb); + for (i = 1; i < num_bh; i++) { + /* get the next sector */ + if (exfat_is_last_sector_in_cluster(sbi, sec)) { + if (p_dir->flags == ALLOC_NO_FAT_CHAIN) + clu++; + else if (exfat_get_next_cluster(sb, &clu)) goto free_es; - off = 0; - ep = (struct exfat_dentry *)bh->b_data; + sec = exfat_cluster_to_sector(sbi, clu); } else { - ep++; - off += DENTRY_SIZE; + sec++; } - pos++; + + bh = sb_bread(sb, sec); + if (!bh) + goto free_es; + es->bh[es->num_bh++] = bh; } - if (file_ep) - *file_ep = &es->entries[0]; - brelse(bh); + /* validiate cached dentries */ + for (i = 1; i < num_entries; i++) { + ep = exfat_get_dentry_cached(es, i); + if (!exfat_validate_entry(exfat_get_entry_type(ep), &mode)) + goto free_es; + } return es; free_es: - kfree(es); -release_bh: - brelse(bh); + exfat_free_dentry_set(es, false); return NULL; } diff --git a/src/exfat_fs.h b/src/exfat_fs.h index 294aa7792bc3ca6c7e334110cba9160577d9affe..c84ae9e605085e0a5b19a2dbe8a9c36ab7efdce6 100644 --- a/src/exfat_fs.h +++ b/src/exfat_fs.h @@ -71,10 +71,8 @@ enum { #define MAX_NAME_LENGTH 255 /* max len of file name excluding NULL */ #define MAX_VFSNAME_BUF_SIZE ((MAX_NAME_LENGTH + 1) * MAX_CHARSET_SIZE) -#define FAT_CACHE_SIZE 128 -#define FAT_CACHE_HASH_SIZE 64 -#define BUF_CACHE_SIZE 256 -#define BUF_CACHE_HASH_SIZE 64 +/* Enough size to hold 256 dentry (even 512 Byte sector) */ +#define DIR_CACHE_SIZE (256*sizeof(struct exfat_dentry)/512+1) #define EXFAT_HINT_NONE -1 #define EXFAT_MIN_SUBDIR 2 @@ -170,14 +168,12 @@ struct exfat_hint { }; struct exfat_entry_set_cache { - /* sector number that contains file_entry */ - sector_t sector; - /* byte offset in the sector */ - unsigned int offset; - /* flag in stream entry. 01 for cluster chain, 03 for contig. */ - int alloc_flag; + struct super_block *sb; + bool modified; + unsigned int start_off; + int num_bh; + struct buffer_head *bh[DIR_CACHE_SIZE]; unsigned int num_entries; - struct exfat_dentry entries[]; }; struct exfat_dir_entry { @@ -451,8 +447,7 @@ int exfat_remove_entries(struct inode *inode, struct exfat_chain *p_dir, int entry, int order, int num_entries); int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir, int entry); -int exfat_update_dir_chksum_with_entry_set(struct super_block *sb, - struct exfat_entry_set_cache *es, int sync); +void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es); int exfat_calc_num_entries(struct exfat_uni_name *p_uniname); int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei, struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname, @@ -463,9 +458,11 @@ int exfat_find_location(struct super_block *sb, struct exfat_chain *p_dir, struct exfat_dentry *exfat_get_dentry(struct super_block *sb, struct exfat_chain *p_dir, int entry, struct buffer_head **bh, sector_t *sector); +struct exfat_dentry *exfat_get_dentry_cached(struct exfat_entry_set_cache *es, + int num); struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, - struct exfat_chain *p_dir, int entry, unsigned int type, - struct exfat_dentry **file_ep); + struct exfat_chain *p_dir, int entry, unsigned int type); +void exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync); int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir); /* inode.c */ diff --git a/src/file.c b/src/file.c index 84f3d31a3a555729b5d2e655f354929018b6b290..8e3f0eef45d77345e6f57ef58f3e86c51c69e905 100644 --- a/src/file.c +++ b/src/file.c @@ -96,11 +96,9 @@ 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 */ @@ -153,12 +151,15 @@ int __exfat_truncate(struct inode *inode, loff_t new_size) /* update the directory entry */ if (!evict) { struct timespec64 ts; + struct exfat_dentry *ep, *ep2; + struct exfat_entry_set_cache *es; es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, - ES_ALL_ENTRIES, &ep); + ES_ALL_ENTRIES); if (!es) return -EIO; - ep2 = ep + 1; + ep = exfat_get_dentry_cached(es, 0); + ep2 = exfat_get_dentry_cached(es, 1); ts = current_time(inode); exfat_set_entry_time(sbi, &ts, @@ -185,10 +186,8 @@ int __exfat_truncate(struct inode *inode, loff_t new_size) 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); + exfat_update_dir_chksum_with_entry_set(es); + exfat_free_dentry_set(es, inode_needs_sync(inode)); } /* cut off from the FAT chain */ diff --git a/src/inode.c b/src/inode.c index 3f367d081cd6dfe6c7cdb475d77e130b64d14d6d..ef7cf7a6d187b8d806383ba7b94daa06342edd22 100644 --- a/src/inode.c +++ b/src/inode.c @@ -19,7 +19,6 @@ 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; @@ -43,11 +42,11 @@ static int __exfat_write_inode(struct inode *inode, int sync) 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); + es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES); if (!es) return -EIO; - ep2 = ep + 1; + ep = exfat_get_dentry_cached(es, 0); + ep2 = exfat_get_dentry_cached(es, 1); ep->dentry.file.attr = cpu_to_le16(exfat_make_attr(inode)); @@ -77,9 +76,9 @@ static int __exfat_write_inode(struct inode *inode, int sync) 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; + exfat_update_dir_chksum_with_entry_set(es); + exfat_free_dentry_set(es, sync); + return 0; } int exfat_write_inode(struct inode *inode, struct writeback_control *wbc) @@ -110,8 +109,6 @@ static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset, 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); @@ -222,34 +219,28 @@ static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset, num_clusters += num_to_be_allocated; *clu = new_clu.dir; - if (ei->dir.dir != DIR_DELETED) { + if (ei->dir.dir != DIR_DELETED && modified) { + struct exfat_dentry *ep; + struct exfat_entry_set_cache *es; + es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, - ES_ALL_ENTRIES, &ep); + ES_ALL_ENTRIES); if (!es) return -EIO; /* get stream entry */ - ep++; + ep = exfat_get_dentry_cached(es, 1); /* 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); + ep->dentry.stream.flags = ei->flags; + 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; + + exfat_update_dir_chksum_with_entry_set(es); + exfat_free_dentry_set(es, inode_needs_sync(inode)); } /* end of if != DIR_DELETED */ diff --git a/src/namei.c b/src/namei.c index 48f4df883f3ba5a30219f8f038a025530a8f8fa2..5b0f35329d63e0b9ab52162e4fbad129601c458d 100644 --- a/src/namei.c +++ b/src/namei.c @@ -600,8 +600,6 @@ static int exfat_find(struct inode *dir, struct qstr *qname, int ret, dentry, num_entries, count; struct exfat_chain cdir; struct exfat_uni_name uni_name; - struct exfat_dentry *ep, *ep2; - struct exfat_entry_set_cache *es = NULL; struct super_block *sb = dir->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); struct exfat_inode_info *ei = EXFAT_I(dir); @@ -660,10 +658,14 @@ static int exfat_find(struct inode *dir, struct qstr *qname, info->num_subdirs = count; } else { - es = exfat_get_dentry_set(sb, &cdir, dentry, ES_2_ENTRIES, &ep); + struct exfat_dentry *ep, *ep2; + struct exfat_entry_set_cache *es; + + es = exfat_get_dentry_set(sb, &cdir, dentry, ES_2_ENTRIES); if (!es) return -EIO; - ep2 = ep + 1; + ep = exfat_get_dentry_cached(es, 0); + ep2 = exfat_get_dentry_cached(es, 1); info->type = exfat_get_entry_type(ep); info->attr = le16_to_cpu(ep->dentry.file.attr); @@ -681,7 +683,7 @@ static int exfat_find(struct inode *dir, struct qstr *qname, exfat_fs_error(sb, "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)", i_size_read(dir), ei->dir.dir, ei->entry); - kfree(es); + exfat_free_dentry_set(es, false); return -EIO; } @@ -700,7 +702,7 @@ static int exfat_find(struct inode *dir, struct qstr *qname, ep->dentry.file.access_time, ep->dentry.file.access_date, 0); - kfree(es); + exfat_free_dentry_set(es, false); if (info->type == TYPE_DIR) { exfat_chain_set(&cdir, info->start_clu, -- 2.31.1