Commit bb88e8da authored by Gao Xiang's avatar Gao Xiang
Browse files

erofs: use meta buffers for xattr operations 

Get rid of old erofs_get_meta_page() within xattr operations by
using on-stack meta buffers in order to prepare subpage and folio
features.

Link: https://lore.kernel.org/r/20220102040017.51352-5-hsiangkao@linux.alibaba.com


Reviewed-by: default avatarLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: default avatarChao Yu <chao@kernel.org>
Signed-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
parent 2b5379f7

fs/erofs/xattr.c

+41 −94
Original line number Original line Diff line number Diff line
@@ -2,39 +2,20 @@ 
/*

/*

 * Copyright (C) 2017-2018 HUAWEI, Inc.

 * Copyright (C) 2017-2018 HUAWEI, Inc.

 *             https://www.huawei.com/

 *             https://www.huawei.com/

 * Copyright (C) 2021-2022, Alibaba Cloud

 */

 */

#include <linux/security.h>

#include <linux/security.h>

#include "xattr.h"

#include "xattr.h"





struct xattr_iter {

struct xattr_iter {

	struct super_block *sb;

	struct super_block *sb;

	struct page *page;

	struct erofs_buf buf;

	void *kaddr;

	void *kaddr;





	erofs_blk_t blkaddr;

	erofs_blk_t blkaddr;

	unsigned int ofs;

	unsigned int ofs;

};

};





static inline void xattr_iter_end(struct xattr_iter *it, bool atomic)

{

	/* the only user of kunmap() is 'init_inode_xattrs' */

	if (!atomic)

		kunmap(it->page);

	else

		kunmap_atomic(it->kaddr);



	unlock_page(it->page);

	put_page(it->page);

}



static inline void xattr_iter_end_final(struct xattr_iter *it)

{

	if (!it->page)

		return;



	xattr_iter_end(it, true);

}



static int init_inode_xattrs(struct inode *inode)

static int init_inode_xattrs(struct inode *inode)

{

{

	struct erofs_inode *const vi = EROFS_I(inode);

	struct erofs_inode *const vi = EROFS_I(inode);
@@ -43,7 +24,6 @@ static int init_inode_xattrs(struct inode *inode) 
	struct erofs_xattr_ibody_header *ih;

	struct erofs_xattr_ibody_header *ih;

	struct super_block *sb;

	struct super_block *sb;

	struct erofs_sb_info *sbi;

	struct erofs_sb_info *sbi;

	bool atomic_map;

	int ret = 0;

	int ret = 0;





	/* the most case is that xattrs of this inode are initialized. */

	/* the most case is that xattrs of this inode are initialized. */
@@ -91,26 +71,23 @@ static int init_inode_xattrs(struct inode *inode) 




	sb = inode->i_sb;

	sb = inode->i_sb;

	sbi = EROFS_SB(sb);

	sbi = EROFS_SB(sb);

	it.buf = __EROFS_BUF_INITIALIZER;

	it.blkaddr = erofs_blknr(iloc(sbi, vi->nid) + vi->inode_isize);

	it.blkaddr = erofs_blknr(iloc(sbi, vi->nid) + vi->inode_isize);

	it.ofs = erofs_blkoff(iloc(sbi, vi->nid) + vi->inode_isize);

	it.ofs = erofs_blkoff(iloc(sbi, vi->nid) + vi->inode_isize);





	it.page = erofs_get_meta_page(sb, it.blkaddr);

	/* read in shared xattr array (non-atomic, see kmalloc below) */

	if (IS_ERR(it.page)) {

	it.kaddr = erofs_read_metabuf(&it.buf, sb, it.blkaddr, EROFS_KMAP);

		ret = PTR_ERR(it.page);

	if (IS_ERR(it.kaddr)) {

		ret = PTR_ERR(it.kaddr);

		goto out_unlock;

		goto out_unlock;

	}

	}





	/* read in shared xattr array (non-atomic, see kmalloc below) */

	it.kaddr = kmap(it.page);

	atomic_map = false;



	ih = (struct erofs_xattr_ibody_header *)(it.kaddr + it.ofs);

	ih = (struct erofs_xattr_ibody_header *)(it.kaddr + it.ofs);



	vi->xattr_shared_count = ih->h_shared_count;

	vi->xattr_shared_count = ih->h_shared_count;

	vi->xattr_shared_xattrs = kmalloc_array(vi->xattr_shared_count,

	vi->xattr_shared_xattrs = kmalloc_array(vi->xattr_shared_count,

						sizeof(uint), GFP_KERNEL);

						sizeof(uint), GFP_KERNEL);

	if (!vi->xattr_shared_xattrs) {

	if (!vi->xattr_shared_xattrs) {

		xattr_iter_end(&it, atomic_map);

		erofs_put_metabuf(&it.buf);

		ret = -ENOMEM;

		ret = -ENOMEM;

		goto out_unlock;

		goto out_unlock;

	}

	}
@@ -122,25 +99,22 @@ static int init_inode_xattrs(struct inode *inode) 
		if (it.ofs >= EROFS_BLKSIZ) {

		if (it.ofs >= EROFS_BLKSIZ) {

			/* cannot be unaligned */

			/* cannot be unaligned */

			DBG_BUGON(it.ofs != EROFS_BLKSIZ);

			DBG_BUGON(it.ofs != EROFS_BLKSIZ);

			xattr_iter_end(&it, atomic_map);





			it.page = erofs_get_meta_page(sb, ++it.blkaddr);

			it.kaddr = erofs_read_metabuf(&it.buf, sb, ++it.blkaddr,

			if (IS_ERR(it.page)) {

						      EROFS_KMAP);

			if (IS_ERR(it.kaddr)) {

				kfree(vi->xattr_shared_xattrs);

				kfree(vi->xattr_shared_xattrs);

				vi->xattr_shared_xattrs = NULL;

				vi->xattr_shared_xattrs = NULL;

				ret = PTR_ERR(it.page);

				ret = PTR_ERR(it.kaddr);

				goto out_unlock;

				goto out_unlock;

			}

			}



			it.kaddr = kmap_atomic(it.page);

			atomic_map = true;

			it.ofs = 0;

			it.ofs = 0;

		}

		}

		vi->xattr_shared_xattrs[i] =

		vi->xattr_shared_xattrs[i] =

			le32_to_cpu(*(__le32 *)(it.kaddr + it.ofs));

			le32_to_cpu(*(__le32 *)(it.kaddr + it.ofs));

		it.ofs += sizeof(__le32);

		it.ofs += sizeof(__le32);

	}

	}

	xattr_iter_end(&it, atomic_map);

	erofs_put_metabuf(&it.buf);





	/* paired with smp_mb() at the beginning of the function. */

	/* paired with smp_mb() at the beginning of the function. */

	smp_mb();

	smp_mb();
@@ -172,19 +146,11 @@ static inline int xattr_iter_fixup(struct xattr_iter *it) 
	if (it->ofs < EROFS_BLKSIZ)

	if (it->ofs < EROFS_BLKSIZ)

		return 0;

		return 0;





	xattr_iter_end(it, true);



	it->blkaddr += erofs_blknr(it->ofs);

	it->blkaddr += erofs_blknr(it->ofs);



	it->kaddr = erofs_read_metabuf(&it->buf, it->sb, it->blkaddr,

	it->page = erofs_get_meta_page(it->sb, it->blkaddr);

				       EROFS_KMAP_ATOMIC);

	if (IS_ERR(it->page)) {

	if (IS_ERR(it->kaddr))

		int err = PTR_ERR(it->page);

		return PTR_ERR(it->kaddr);



		it->page = NULL;

		return err;

	}



	it->kaddr = kmap_atomic(it->page);

	it->ofs = erofs_blkoff(it->ofs);

	it->ofs = erofs_blkoff(it->ofs);

	return 0;

	return 0;

}

}
@@ -207,11 +173,10 @@ static int inline_xattr_iter_begin(struct xattr_iter *it, 
	it->blkaddr = erofs_blknr(iloc(sbi, vi->nid) + inline_xattr_ofs);

	it->blkaddr = erofs_blknr(iloc(sbi, vi->nid) + inline_xattr_ofs);

	it->ofs = erofs_blkoff(iloc(sbi, vi->nid) + inline_xattr_ofs);

	it->ofs = erofs_blkoff(iloc(sbi, vi->nid) + inline_xattr_ofs);





	it->page = erofs_get_meta_page(inode->i_sb, it->blkaddr);

	it->kaddr = erofs_read_metabuf(&it->buf, inode->i_sb, it->blkaddr,

	if (IS_ERR(it->page))

				       EROFS_KMAP_ATOMIC);

		return PTR_ERR(it->page);

	if (IS_ERR(it->kaddr))



		return PTR_ERR(it->kaddr);

	it->kaddr = kmap_atomic(it->page);

	return vi->xattr_isize - xattr_header_sz;

	return vi->xattr_isize - xattr_header_sz;

}

}
@@ -272,7 +237,7 @@ static int xattr_foreach(struct xattr_iter *it, 
			it->ofs = 0;

			it->ofs = 0;

		}

		}





		slice = min_t(unsigned int, PAGE_SIZE - it->ofs,

		slice = min_t(unsigned int, EROFS_BLKSIZ - it->ofs,

			      entry.e_name_len - processed);

			      entry.e_name_len - processed);





		/* handle name */

		/* handle name */
@@ -307,7 +272,7 @@ static int xattr_foreach(struct xattr_iter *it, 
			it->ofs = 0;

			it->ofs = 0;

		}

		}





		slice = min_t(unsigned int, PAGE_SIZE - it->ofs,

		slice = min_t(unsigned int, EROFS_BLKSIZ - it->ofs,

			      value_sz - processed);

			      value_sz - processed);

		op->value(it, processed, it->kaddr + it->ofs, slice);

		op->value(it, processed, it->kaddr + it->ofs, slice);

		it->ofs += slice;

		it->ofs += slice;
@@ -386,8 +351,6 @@ static int inline_getxattr(struct inode *inode, struct getxattr_iter *it) 
		if (ret != -ENOATTR)

		if (ret != -ENOATTR)

			break;

			break;

	}

	}

	xattr_iter_end_final(&it->it);



	return ret ? ret : it->buffer_size;

	return ret ? ret : it->buffer_size;

}

}
@@ -404,26 +367,16 @@ static int shared_getxattr(struct inode *inode, struct getxattr_iter *it) 
			xattrblock_addr(sbi, vi->xattr_shared_xattrs[i]);

			xattrblock_addr(sbi, vi->xattr_shared_xattrs[i]);





		it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]);

		it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]);



		it->it.kaddr = erofs_read_metabuf(&it->it.buf, sb, blkaddr,

		if (!i || blkaddr != it->it.blkaddr) {

						  EROFS_KMAP_ATOMIC);

			if (i)

		if (IS_ERR(it->it.kaddr))

				xattr_iter_end(&it->it, true);

			return PTR_ERR(it->it.kaddr);



			it->it.page = erofs_get_meta_page(sb, blkaddr);

			if (IS_ERR(it->it.page))

				return PTR_ERR(it->it.page);



			it->it.kaddr = kmap_atomic(it->it.page);

		it->it.blkaddr = blkaddr;

		it->it.blkaddr = blkaddr;

		}





		ret = xattr_foreach(&it->it, &find_xattr_handlers, NULL);

		ret = xattr_foreach(&it->it, &find_xattr_handlers, NULL);

		if (ret != -ENOATTR)

		if (ret != -ENOATTR)

			break;

			break;

	}

	}

	if (vi->xattr_shared_count)

		xattr_iter_end_final(&it->it);



	return ret ? ret : it->buffer_size;

	return ret ? ret : it->buffer_size;

}

}
@@ -452,10 +405,11 @@ int erofs_getxattr(struct inode *inode, int index, 
		return ret;

		return ret;





	it.index = index;

	it.index = index;



	it.name.len = strlen(name);

	it.name.len = strlen(name);

	if (it.name.len > EROFS_NAME_LEN)

	if (it.name.len > EROFS_NAME_LEN)

		return -ERANGE;

		return -ERANGE;



	it.it.buf = __EROFS_BUF_INITIALIZER;

	it.name.name = name;

	it.name.name = name;





	it.buffer = buffer;

	it.buffer = buffer;
@@ -465,6 +419,7 @@ int erofs_getxattr(struct inode *inode, int index, 
	ret = inline_getxattr(inode, &it);

	ret = inline_getxattr(inode, &it);

	if (ret == -ENOATTR)

	if (ret == -ENOATTR)

		ret = shared_getxattr(inode, &it);

		ret = shared_getxattr(inode, &it);

	erofs_put_metabuf(&it.it.buf);

	return ret;

	return ret;

}

}
@@ -607,7 +562,6 @@ static int inline_listxattr(struct listxattr_iter *it) 
		if (ret)

		if (ret)

			break;

			break;

	}

	}

	xattr_iter_end_final(&it->it);

	return ret ? ret : it->buffer_ofs;

	return ret ? ret : it->buffer_ofs;

}

}
@@ -625,25 +579,16 @@ static int shared_listxattr(struct listxattr_iter *it) 
			xattrblock_addr(sbi, vi->xattr_shared_xattrs[i]);

			xattrblock_addr(sbi, vi->xattr_shared_xattrs[i]);





		it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]);

		it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]);

		if (!i || blkaddr != it->it.blkaddr) {

		it->it.kaddr = erofs_read_metabuf(&it->it.buf, sb, blkaddr,

			if (i)

						  EROFS_KMAP_ATOMIC);

				xattr_iter_end(&it->it, true);

		if (IS_ERR(it->it.kaddr))



			return PTR_ERR(it->it.kaddr);

			it->it.page = erofs_get_meta_page(sb, blkaddr);

			if (IS_ERR(it->it.page))

				return PTR_ERR(it->it.page);



			it->it.kaddr = kmap_atomic(it->it.page);

		it->it.blkaddr = blkaddr;

		it->it.blkaddr = blkaddr;

		}





		ret = xattr_foreach(&it->it, &list_xattr_handlers, NULL);

		ret = xattr_foreach(&it->it, &list_xattr_handlers, NULL);

		if (ret)

		if (ret)

			break;

			break;

	}

	}

	if (vi->xattr_shared_count)

		xattr_iter_end_final(&it->it);



	return ret ? ret : it->buffer_ofs;

	return ret ? ret : it->buffer_ofs;

}

}
@@ -659,6 +604,7 @@ ssize_t erofs_listxattr(struct dentry *dentry, 
	if (ret)

	if (ret)

		return ret;

		return ret;





	it.it.buf = __EROFS_BUF_INITIALIZER;

	it.dentry = dentry;

	it.dentry = dentry;

	it.buffer = buffer;

	it.buffer = buffer;

	it.buffer_size = buffer_size;

	it.buffer_size = buffer_size;
@@ -667,9 +613,10 @@ ssize_t erofs_listxattr(struct dentry *dentry, 
	it.it.sb = dentry->d_sb;

	it.it.sb = dentry->d_sb;





	ret = inline_listxattr(&it);

	ret = inline_listxattr(&it);

	if (ret < 0 && ret != -ENOATTR)

	if (ret >= 0 || ret == -ENOATTR)

		ret = shared_listxattr(&it);

	erofs_put_metabuf(&it.it.buf);

	return ret;

	return ret;

	return shared_listxattr(&it);

}

}





#ifdef CONFIG_EROFS_FS_POSIX_ACL

#ifdef CONFIG_EROFS_FS_POSIX_ACL

fs/erofs/xattr.h

+0 −1
Original line number Original line Diff line number Diff line
@@ -86,4 +86,3 @@ struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu); 
#endif

#endif





#endif
 
#endif