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: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

diff --git a/fs/erofs/data.c b/fs/erofs/data.c
index b2a22aabc9bc1ec3b12d68ff2dfcfdb97fd30f4b..09c46fbdb9b29c0db1970054ab50042621d6ab3c 100644 (file)
--- a/fs/erofs/data.c
+++ b/fs/erofs/data.c
@@ -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.

diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index 92728da1d20679dea37c90c26f95619474296300..d13e0709599c7d35a85d22464fe3fb06be0d2ca2 100644 (file)
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -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 = {

diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index a9fc5245015b47bbb5e6fb2e5217c39fcb5c9b08..91089ab8a816e5505dcb1a807d907284d59ab59c 100644 (file)
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -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)

diff --git a/fs/erofs/namei.c b/fs/erofs/namei.c
index a8271ce5e13ffaec79fca8e446a26f359ac920e5..8629e616028cbc79f98b18d672d17d58738af55b 100644 (file)
--- a/fs/erofs/namei.c
+++ b/fs/erofs/namei.c
@@ -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,
 };

diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index c2a31810abeb9111025f507f8e4057ffa804e2b0..9fb98d85a3ceaaaf201bbb05a7ef142a1a7f8fc5 100644 (file)
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -675,3 +675,41 @@ out:
        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,
+};