Commit eadcd6b5 authored by Gao Xiang's avatar Gao Xiang
Browse files

erofs: add fiemap support with iomap 

This adds fiemap support for both uncompressed files and compressed
files by using iomap infrastructure.

Link: https://lore.kernel.org/r/20210813052931.203280-3-hsiangkao@linux.alibaba.com


Reviewed-by: default avatarChao Yu <chao@kernel.org>
Signed-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
parent d95ae5e2

fs/erofs/data.c

+14 −1
Original line number Diff line number Diff line
@@ -5,7 +5,6 @@ 
 */

#include "internal.h"

#include <linux/prefetch.h>

#include <linux/iomap.h>

#include <linux/dax.h>

#include <trace/events/erofs.h>
@@ -152,6 +151,20 @@ static const struct iomap_ops erofs_iomap_ops = { 
	.iomap_end = erofs_iomap_end,

};



int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,

		 u64 start, u64 len)

{

	if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout)) {

#ifdef CONFIG_EROFS_FS_ZIP

		return iomap_fiemap(inode, fieinfo, start, len,

				    &z_erofs_iomap_report_ops);

#else

		return -EOPNOTSUPP;

#endif

	}

	return iomap_fiemap(inode, fieinfo, start, len, &erofs_iomap_ops);

}



/*

 * since we dont have write or truncate flows, so no inode

 * locking needs to be held at the moment.

fs/erofs/inode.c

+1 −0
Original line number Diff line number Diff line
@@ -365,6 +365,7 @@ const struct inode_operations erofs_generic_iops = { 
	.getattr = erofs_getattr,

	.listxattr = erofs_listxattr,

	.get_acl = erofs_get_acl,

	.fiemap = erofs_fiemap,

};



const struct inode_operations erofs_symlink_iops = {

fs/erofs/internal.h

+5 −0
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
#include <linux/magic.h>

#include <linux/slab.h>

#include <linux/vmalloc.h>

#include <linux/iomap.h>

#include "erofs_fs.h"



/* redefine pr_fmt "erofs: " */
@@ -363,6 +364,8 @@ struct erofs_map_blocks { 
#define EROFS_GET_BLOCKS_FIEMAP	0x0002



/* zmap.c */

extern const struct iomap_ops z_erofs_iomap_report_ops;



#ifdef CONFIG_EROFS_FS_ZIP

int z_erofs_fill_inode(struct inode *inode);

int z_erofs_map_blocks_iter(struct inode *inode,
@@ -381,6 +384,8 @@ static inline int z_erofs_map_blocks_iter(struct inode *inode, 
/* data.c */

extern const struct file_operations erofs_file_fops;

struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr);

int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,

		 u64 start, u64 len);



/* inode.c */

static inline unsigned long erofs_inode_hash(erofs_nid_t nid)

fs/erofs/namei.c

+1 −0
Original line number Diff line number Diff line
@@ -245,4 +245,5 @@ const struct inode_operations erofs_dir_iops = { 
	.getattr = erofs_getattr,

	.listxattr = erofs_listxattr,

	.get_acl = erofs_get_acl,

	.fiemap = erofs_fiemap,

};

fs/erofs/zmap.c

+38 −0
Original line number Diff line number Diff line
@@ -675,3 +675,41 @@ int z_erofs_map_blocks_iter(struct inode *inode, 
	DBG_BUGON(err < 0 && err != -ENOMEM);

	return err;

}



static int z_erofs_iomap_begin_report(struct inode *inode, loff_t offset,

				loff_t length, unsigned int flags,

				struct iomap *iomap, struct iomap *srcmap)

{

	int ret;

	struct erofs_map_blocks map = { .m_la = offset };



	ret = z_erofs_map_blocks_iter(inode, &map, EROFS_GET_BLOCKS_FIEMAP);

	if (map.mpage)

		put_page(map.mpage);

	if (ret < 0)

		return ret;



	iomap->bdev = inode->i_sb->s_bdev;

	iomap->offset = map.m_la;

	iomap->length = map.m_llen;

	if (map.m_flags & EROFS_MAP_MAPPED) {

		iomap->type = IOMAP_MAPPED;

		iomap->addr = map.m_pa;

	} else {

		iomap->type = IOMAP_HOLE;

		iomap->addr = IOMAP_NULL_ADDR;

		/*

		 * No strict rule how to describe extents for post EOF, yet

		 * we need do like below. Otherwise, iomap itself will get

		 * into an endless loop on post EOF.

		 */

		if (iomap->offset >= inode->i_size)

			iomap->length = length + map.m_la - offset;

	}

	iomap->flags = 0;

	return 0;

}



const struct iomap_ops z_erofs_iomap_report_ops = {

	.iomap_begin = z_erofs_iomap_begin_report,

};