From 8b7adf1dff3d5baf687acda936f193f80b7e0179 Mon Sep 17 00:00:00 2001 From: Jia Zhu Date: Sun, 18 Sep 2022 12:34:53 +0800 Subject: erofs: introduce fscache-based domain A new fscache-based shared domain mode is going to be introduced for erofs. In which case, same data blobs in same domain will be shared and reused to reduce on-disk space usage. The implementation of sharing blobs will be introduced in subsequent patches. Signed-off-by: Jia Zhu Reviewed-by: Jingbo Xu Link: https://lore.kernel.org/r/20220918043456.147-4-zhujia.zj@bytedance.com Signed-off-by: Gao Xiang --- fs/erofs/fscache.c | 129 +++++++++++++++++++++++++++++++++++++++++++++------- fs/erofs/internal.h | 9 ++++ 2 files changed, 121 insertions(+), 17 deletions(-) (limited to 'fs/erofs') diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c index 1eb63987e815..8a1be6077ca4 100644 --- a/fs/erofs/fscache.c +++ b/fs/erofs/fscache.c @@ -1,10 +1,14 @@ // SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2022, Alibaba Cloud + * Copyright (C) 2022, Bytedance Inc. All rights reserved. */ #include #include "internal.h" +static DEFINE_MUTEX(erofs_domain_list_lock); +static LIST_HEAD(erofs_domain_list); + static struct netfs_io_request *erofs_fscache_alloc_request(struct address_space *mapping, loff_t start, size_t len) { @@ -421,6 +425,99 @@ const struct address_space_operations erofs_fscache_access_aops = { .readahead = erofs_fscache_readahead, }; +static void erofs_fscache_domain_put(struct erofs_domain *domain) +{ + if (!domain) + return; + mutex_lock(&erofs_domain_list_lock); + if (refcount_dec_and_test(&domain->ref)) { + list_del(&domain->list); + mutex_unlock(&erofs_domain_list_lock); + fscache_relinquish_volume(domain->volume, NULL, false); + kfree(domain->domain_id); + kfree(domain); + return; + } + mutex_unlock(&erofs_domain_list_lock); +} + +static int erofs_fscache_register_volume(struct super_block *sb) +{ + struct erofs_sb_info *sbi = EROFS_SB(sb); + char *domain_id = sbi->opt.domain_id; + struct fscache_volume *volume; + char *name; + int ret = 0; + + name = kasprintf(GFP_KERNEL, "erofs,%s", + domain_id ? domain_id : sbi->opt.fsid); + if (!name) + return -ENOMEM; + + volume = fscache_acquire_volume(name, NULL, NULL, 0); + if (IS_ERR_OR_NULL(volume)) { + erofs_err(sb, "failed to register volume for %s", name); + ret = volume ? PTR_ERR(volume) : -EOPNOTSUPP; + volume = NULL; + } + + sbi->volume = volume; + kfree(name); + return ret; +} + +static int erofs_fscache_init_domain(struct super_block *sb) +{ + int err; + struct erofs_domain *domain; + struct erofs_sb_info *sbi = EROFS_SB(sb); + + domain = kzalloc(sizeof(struct erofs_domain), GFP_KERNEL); + if (!domain) + return -ENOMEM; + + domain->domain_id = kstrdup(sbi->opt.domain_id, GFP_KERNEL); + if (!domain->domain_id) { + kfree(domain); + return -ENOMEM; + } + + err = erofs_fscache_register_volume(sb); + if (err) + goto out; + + domain->volume = sbi->volume; + refcount_set(&domain->ref, 1); + list_add(&domain->list, &erofs_domain_list); + sbi->domain = domain; + return 0; +out: + kfree(domain->domain_id); + kfree(domain); + return err; +} + +static int erofs_fscache_register_domain(struct super_block *sb) +{ + int err; + struct erofs_domain *domain; + struct erofs_sb_info *sbi = EROFS_SB(sb); + + mutex_lock(&erofs_domain_list_lock); + list_for_each_entry(domain, &erofs_domain_list, list) { + if (!strcmp(domain->domain_id, sbi->opt.domain_id)) { + sbi->domain = domain; + sbi->volume = domain->volume; + refcount_inc(&domain->ref); + mutex_unlock(&erofs_domain_list_lock); + return 0; + } + } + err = erofs_fscache_init_domain(sb); + mutex_unlock(&erofs_domain_list_lock); + return err; +} + struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb, char *name, bool need_inode) { @@ -484,27 +581,19 @@ void erofs_fscache_unregister_cookie(struct erofs_fscache *ctx) int erofs_fscache_register_fs(struct super_block *sb) { + int ret; struct erofs_sb_info *sbi = EROFS_SB(sb); - struct fscache_volume *volume; struct erofs_fscache *fscache; - char *name; - - name = kasprintf(GFP_KERNEL, "erofs,%s", sbi->opt.fsid); - if (!name) - return -ENOMEM; - volume = fscache_acquire_volume(name, NULL, NULL, 0); - if (IS_ERR_OR_NULL(volume)) { - erofs_err(sb, "failed to register volume for %s", name); - kfree(name); - return volume ? PTR_ERR(volume) : -EOPNOTSUPP; - } - - sbi->volume = volume; - kfree(name); + if (sbi->opt.domain_id) + ret = erofs_fscache_register_domain(sb); + else + ret = erofs_fscache_register_volume(sb); + if (ret) + return ret; + /* acquired domain/volume will be relinquished in kill_sb() on error */ fscache = erofs_fscache_register_cookie(sb, sbi->opt.fsid, true); - /* acquired volume will be relinquished in kill_sb() */ if (IS_ERR(fscache)) return PTR_ERR(fscache); @@ -517,7 +606,13 @@ void erofs_fscache_unregister_fs(struct super_block *sb) struct erofs_sb_info *sbi = EROFS_SB(sb); erofs_fscache_unregister_cookie(sbi->s_fscache); - fscache_relinquish_volume(sbi->volume, NULL, false); + + if (sbi->domain) + erofs_fscache_domain_put(sbi->domain); + else + fscache_relinquish_volume(sbi->volume, NULL, false); + sbi->s_fscache = NULL; sbi->volume = NULL; + sbi->domain = NULL; } diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 39fb124ce670..93fc4ad61cfb 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -76,6 +76,7 @@ struct erofs_mount_opts { #endif unsigned int mount_opt; char *fsid; + char *domain_id; }; struct erofs_dev_context { @@ -98,6 +99,13 @@ struct erofs_sb_lz4_info { u16 max_pclusterblks; }; +struct erofs_domain { + refcount_t ref; + struct list_head list; + struct fscache_volume *volume; + char *domain_id; +}; + struct erofs_fscache { struct fscache_cookie *cookie; struct inode *inode; @@ -157,6 +165,7 @@ struct erofs_sb_info { /* fscache support */ struct fscache_volume *volume; struct erofs_fscache *s_fscache; + struct erofs_domain *domain; }; #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info) -- cgit 1.4.1