From: Jia Zhu zhujia.zj@bytedance.com
anolis inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IB5UKT
Reference: https://gitee.com/anolis/cloud-kernel/commit/8f55d7266411
--------------------------------
ANBZ: #3234
commit 7d41963759feb3cfa4c1164b8b9db5d1f055932d upstream.
Several erofs filesystems can belong to one domain, and data blobs can be shared among these erofs filesystems of same domain.
Users could specify domain_id mount option to create or join into a domain.
Signed-off-by: Jia Zhu zhujia.zj@bytedance.com Reviewed-by: Jingbo Xu jefflexu@linux.alibaba.com Link: https://lore.kernel.org/r/20220918110150.6338-1-zhujia.zj@bytedance.com Signed-off-by: Gao Xiang hsiangkao@linux.alibaba.com Signed-off-by: Jingbo Xu jefflexu@linux.alibaba.com Reviewed-by: Joseph Qi joseph.qi@linux.alibaba.com Link: https://gitee.com/anolis/cloud-kernel/pulls/893 Signed-off-by: Baokun Li libaokun1@huawei.com --- fs/erofs/fscache.c | 100 +++++++++++++++++++++++++++++++++++++++++--- fs/erofs/internal.h | 3 ++ 2 files changed, 97 insertions(+), 6 deletions(-)
diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c index f99e2fd3a146..217290ab8a8c 100644 --- a/fs/erofs/fscache.c +++ b/fs/erofs/fscache.c @@ -3,9 +3,11 @@ * Copyright (C) 2022, Bytedance Inc. All rights reserved. */ #include <linux/fscache.h> +#include <linux/mount.h> #include "internal.h"
static DEFINE_MUTEX(erofs_domain_list_lock); +static DEFINE_MUTEX(erofs_domain_cookies_lock); static LIST_HEAD(erofs_domain_list); static struct vfsmount *erofs_pseudo_mnt;
@@ -380,8 +382,9 @@ static int erofs_fscache_register_domain(struct super_block *sb) return err; }
-struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb, - char *name, bool need_inode) +static +struct erofs_fscache *erofs_fscache_acquire_cookie(struct super_block *sb, + char *name, bool need_inode) { struct erofs_fscache *ctx; struct fscache_cookie *cookie; @@ -431,17 +434,102 @@ struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb, return ERR_PTR(ret); }
-void erofs_fscache_unregister_cookie(struct erofs_fscache *ctx) +static void erofs_fscache_relinquish_cookie(struct erofs_fscache *ctx) { - if (!ctx) - return; - //fscache_unuse_cookie(ctx->cookie, NULL, NULL); fscache_relinquish_cookie(ctx->cookie, NULL, false); iput(ctx->inode); + kfree(ctx->name); kfree(ctx); }
+static +struct erofs_fscache *erofs_fscache_domain_init_cookie(struct super_block *sb, + char *name, bool need_inode) +{ + int err; + struct inode *inode; + struct erofs_fscache *ctx; + struct erofs_domain *domain = EROFS_SB(sb)->domain; + + ctx = erofs_fscache_acquire_cookie(sb, name, need_inode); + if (IS_ERR(ctx)) + return ctx; + + ctx->name = kstrdup(name, GFP_KERNEL); + if (!ctx->name) { + err = -ENOMEM; + goto out; + } + + inode = new_inode(erofs_pseudo_mnt->mnt_sb); + if (!inode) { + err = -ENOMEM; + goto out; + } + + ctx->domain = domain; + ctx->anon_inode = inode; + inode->i_private = ctx; + refcount_inc(&domain->ref); + return ctx; +out: + erofs_fscache_relinquish_cookie(ctx); + return ERR_PTR(err); +} + +static +struct erofs_fscache *erofs_domain_register_cookie(struct super_block *sb, + char *name, bool need_inode) +{ + struct inode *inode; + struct erofs_fscache *ctx; + struct erofs_domain *domain = EROFS_SB(sb)->domain; + struct super_block *psb = erofs_pseudo_mnt->mnt_sb; + + mutex_lock(&erofs_domain_cookies_lock); + list_for_each_entry(inode, &psb->s_inodes, i_sb_list) { + ctx = inode->i_private; + if (!ctx || ctx->domain != domain || strcmp(ctx->name, name)) + continue; + igrab(inode); + mutex_unlock(&erofs_domain_cookies_lock); + return ctx; + } + ctx = erofs_fscache_domain_init_cookie(sb, name, need_inode); + mutex_unlock(&erofs_domain_cookies_lock); + return ctx; +} + +struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb, + char *name, bool need_inode) +{ + if (EROFS_SB(sb)->opt.domain_id) + return erofs_domain_register_cookie(sb, name, need_inode); + return erofs_fscache_acquire_cookie(sb, name, need_inode); +} + +void erofs_fscache_unregister_cookie(struct erofs_fscache *ctx) +{ + bool drop; + struct erofs_domain *domain; + + if (!ctx) + return; + domain = ctx->domain; + if (domain) { + mutex_lock(&erofs_domain_cookies_lock); + drop = atomic_read(&ctx->anon_inode->i_count) == 1; + iput(ctx->anon_inode); + mutex_unlock(&erofs_domain_cookies_lock); + if (!drop) + return; + } + + erofs_fscache_relinquish_cookie(ctx); + erofs_fscache_domain_put(domain); +} + int erofs_fscache_register_fs(struct super_block *sb) { int ret; diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 7ec852b7d59d..82a47b6ff9ca 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -91,6 +91,9 @@ struct erofs_domain { struct erofs_fscache { struct fscache_cookie *cookie; struct inode *inode; + struct inode *anon_inode; + struct erofs_domain *domain; + char *name; };
struct erofs_sb_info {