Commit aab4ed58 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'erofs-for-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs 

Pull erofs updates from Gao Xiang:
 "In this cycle, we continue converting to use meta buffers for all
  remaining uncompressed paths to prepare for the upcoming subpage,
  folio and fscache features.

  We also fixed a double-free issue when sysfs initialization fails,
  which was reported by syzbot.

  Besides, in order for the userspace to control per-file timestamp
  easier, we now switch to record mtime instead of ctime with a
  compatible feature marked. And there are also some code cleanups and
  documentation update as usual.

  Summary:

   - Avoid using page structure directly for all uncompressed paths

   - Fix a double-free issue when sysfs initialization fails

   - Complete DAX description for erofs

   - Use mtime instead since there's no (easy) way for users to control
     ctime

   - Several code cleanups"

* tag 'erofs-for-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: rename ctime to mtime
  erofs: use meta buffers for inode lookup
  erofs: use meta buffers for reading directories
  fs: erofs: add sanity check for kobject in erofs_unregister_sysfs
  erofs: refine managed inode stuffs
  erofs: clean up z_erofs_extent_lookback
  erofs: silence warnings related to impossible m_plen
  Documentation/filesystem/dax: update DAX description on erofs
  erofs: clean up preload_compressed_pages()
  erofs: get rid of `struct z_erofs_collector'
  erofs: use meta buffers for erofs_read_superblock()
parents 881b5687 a1108dcd

Documentation/filesystems/dax.rst

+3 −3
Original line number Diff line number Diff line
@@ -23,11 +23,11 @@ on it as usual. The `DAX` code currently only supports files with a block 
size equal to your kernel's `PAGE_SIZE`, so you may need to specify a block

size when creating the filesystem.



Currently 4 filesystems support `DAX`: ext2, ext4, xfs and virtiofs.

Currently 5 filesystems support `DAX`: ext2, ext4, xfs, virtiofs and erofs.

Enabling `DAX` on them is different.



Enabling DAX on ext2

--------------------

Enabling DAX on ext2 and erofs

------------------------------



When mounting the filesystem, use the ``-o dax`` option on the command line or

add 'dax' to the options in ``/etc/fstab``.  This works to enable `DAX` on all files

Documentation/filesystems/erofs.rst

+1 −1
Original line number Diff line number Diff line
@@ -40,7 +40,7 @@ Here is the main features of EROFS: 
   Inode metadata size    32 bytes      64 bytes

   Max file size          4 GB          16 EB (also limited by max. vol size)

   Max uids/gids          65536         4294967296

   File change time       no            yes (64 + 32-bit timestamp)

   Per-inode timestamp    no            yes (64 + 32-bit timestamp)

   Max hardlinks          65536         4294967296

   Metadata reserved      4 bytes       14 bytes

   =====================  ============  =====================================

fs/erofs/data.c

+9 −3
Original line number Diff line number Diff line
@@ -28,10 +28,10 @@ void erofs_put_metabuf(struct erofs_buf *buf) 
	buf->page = NULL;

}



void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,

void *erofs_bread(struct erofs_buf *buf, struct inode *inode,

		  erofs_blk_t blkaddr, enum erofs_kmap_type type)

{

	struct address_space *const mapping = sb->s_bdev->bd_inode->i_mapping;

	struct address_space *const mapping = inode->i_mapping;

	erofs_off_t offset = blknr_to_addr(blkaddr);

	pgoff_t index = offset >> PAGE_SHIFT;

	struct page *page = buf->page;
@@ -60,6 +60,12 @@ void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb, 
	return buf->base + (offset & ~PAGE_MASK);

}



void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,

			 erofs_blk_t blkaddr, enum erofs_kmap_type type)

{

	return erofs_bread(buf, sb->s_bdev->bd_inode, blkaddr, type);

}



static int erofs_map_blocks_flatmode(struct inode *inode,

				     struct erofs_map_blocks *map,

				     int flags)

fs/erofs/dir.c

+6 −15
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 
/*

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

 *             https://www.huawei.com/

 * Copyright (C) 2022, Alibaba Cloud

 */

#include "internal.h"
@@ -67,7 +68,7 @@ static int erofs_fill_dentries(struct inode *dir, struct dir_context *ctx, 
static int erofs_readdir(struct file *f, struct dir_context *ctx)

{

	struct inode *dir = file_inode(f);

	struct address_space *mapping = dir->i_mapping;

	struct erofs_buf buf = __EROFS_BUF_INITIALIZER;

	const size_t dirsize = i_size_read(dir);

	unsigned int i = ctx->pos / EROFS_BLKSIZ;

	unsigned int ofs = ctx->pos % EROFS_BLKSIZ;
@@ -75,26 +76,19 @@ static int erofs_readdir(struct file *f, struct dir_context *ctx) 
	bool initial = true;



	while (ctx->pos < dirsize) {

		struct page *dentry_page;

		struct erofs_dirent *de;

		unsigned int nameoff, maxsize;



		dentry_page = read_mapping_page(mapping, i, NULL);

		if (dentry_page == ERR_PTR(-ENOMEM)) {

			err = -ENOMEM;

			break;

		} else if (IS_ERR(dentry_page)) {

		de = erofs_bread(&buf, dir, i, EROFS_KMAP);

		if (IS_ERR(de)) {

			erofs_err(dir->i_sb,

				  "fail to readdir of logical block %u of nid %llu",

				  i, EROFS_I(dir)->nid);

			err = -EFSCORRUPTED;

			err = PTR_ERR(de);

			break;

		}



		de = (struct erofs_dirent *)kmap(dentry_page);



		nameoff = le16_to_cpu(de->nameoff);



		if (nameoff < sizeof(struct erofs_dirent) ||

		    nameoff >= PAGE_SIZE) {

			erofs_err(dir->i_sb,
@@ -119,10 +113,6 @@ static int erofs_readdir(struct file *f, struct dir_context *ctx) 
		err = erofs_fill_dentries(dir, ctx, de, &ofs,

					  nameoff, maxsize);

skip_this:

		kunmap(dentry_page);



		put_page(dentry_page);



		ctx->pos = blknr_to_addr(i) + ofs;



		if (err)
@@ -130,6 +120,7 @@ static int erofs_readdir(struct file *f, struct dir_context *ctx) 
		++i;

		ofs = 0;

	}

	erofs_put_metabuf(&buf);

	return err < 0 ? err : 0;

}

fs/erofs/erofs_fs.h

+3 −2
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#define EROFS_SUPER_OFFSET      1024



#define EROFS_FEATURE_COMPAT_SB_CHKSUM          0x00000001

#define EROFS_FEATURE_COMPAT_MTIME              0x00000002



/*

 * Any bits that aren't in EROFS_ALL_FEATURE_INCOMPAT should
@@ -186,8 +187,8 @@ struct erofs_inode_extended { 


	__le32 i_uid;

	__le32 i_gid;

	__le64 i_ctime;

	__le32 i_ctime_nsec;

	__le64 i_mtime;

	__le32 i_mtime_nsec;

	__le32 i_nlink;

	__u8   i_reserved2[16];

};