Commit 3c265d7d authored by Jeffle Xu's avatar Jeffle Xu Committed by Gao Xiang
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erofs: add anonymous inode caching metadata for data blobs 



Introduce one anonymous inode for data blobs so that erofs can cache
metadata directly within such anonymous inode.

Signed-off-by: default avatarJeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-14-jefflexu@linux.alibaba.com


Acked-by: default avatarChao Yu <chao@kernel.org>
Signed-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
parent b02c602f

fs/erofs/fscache.c

+36 −3
Original line number Diff line number Diff line
@@ -5,12 +5,17 @@ 
#include <linux/fscache.h>

#include "internal.h"



static const struct address_space_operations erofs_fscache_meta_aops = {

};



int erofs_fscache_register_cookie(struct super_block *sb,

				  struct erofs_fscache **fscache, char *name)

				  struct erofs_fscache **fscache,

				  char *name, bool need_inode)

{

	struct fscache_volume *volume = EROFS_SB(sb)->volume;

	struct erofs_fscache *ctx;

	struct fscache_cookie *cookie;

	int ret;



	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);

	if (!ctx)
@@ -20,15 +25,40 @@ int erofs_fscache_register_cookie(struct super_block *sb, 
					name, strlen(name), NULL, 0, 0);

	if (!cookie) {

		erofs_err(sb, "failed to get cookie for %s", name);

		kfree(name);

		return -EINVAL;

		ret = -EINVAL;

		goto err;

	}



	fscache_use_cookie(cookie, false);

	ctx->cookie = cookie;



	if (need_inode) {

		struct inode *const inode = new_inode(sb);



		if (!inode) {

			erofs_err(sb, "failed to get anon inode for %s", name);

			ret = -ENOMEM;

			goto err_cookie;

		}



		set_nlink(inode, 1);

		inode->i_size = OFFSET_MAX;

		inode->i_mapping->a_ops = &erofs_fscache_meta_aops;

		mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);



		ctx->inode = inode;

	}



	*fscache = ctx;

	return 0;



err_cookie:

	fscache_unuse_cookie(ctx->cookie, NULL, NULL);

	fscache_relinquish_cookie(ctx->cookie, false);

	ctx->cookie = NULL;

err:

	kfree(ctx);

	return ret;

}



void erofs_fscache_unregister_cookie(struct erofs_fscache **fscache)
@@ -42,6 +72,9 @@ void erofs_fscache_unregister_cookie(struct erofs_fscache **fscache) 
	fscache_relinquish_cookie(ctx->cookie, false);

	ctx->cookie = NULL;



	iput(ctx->inode);

	ctx->inode = NULL;



	kfree(ctx);

	*fscache = NULL;

}

fs/erofs/internal.h

+4 −2
Original line number Diff line number Diff line
@@ -99,6 +99,7 @@ struct erofs_sb_lz4_info { 


struct erofs_fscache {

	struct fscache_cookie *cookie;

	struct inode *inode;

};



struct erofs_sb_info {
@@ -607,7 +608,8 @@ int erofs_fscache_register_fs(struct super_block *sb); 
void erofs_fscache_unregister_fs(struct super_block *sb);



int erofs_fscache_register_cookie(struct super_block *sb,

				  struct erofs_fscache **fscache, char *name);

				  struct erofs_fscache **fscache,

				  char *name, bool need_inode);

void erofs_fscache_unregister_cookie(struct erofs_fscache **fscache);

#else

static inline int erofs_fscache_register_fs(struct super_block *sb)
@@ -618,7 +620,7 @@ static inline void erofs_fscache_unregister_fs(struct super_block *sb) {} 


static inline int erofs_fscache_register_cookie(struct super_block *sb,

						struct erofs_fscache **fscache,

						char *name)

						char *name, bool need_inode)

{

	return -EOPNOTSUPP;

}