Implement the data plane of reading data from data blobs over fscache
for non-inline layout.
Signed-off-by: Jeffle Xu <jeffl...@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiang...@linux.alibaba.com>
---
fs/erofs/fscache.c | 51 +++++++++++++++++++++++++++++++++++++++++++++
fs/erofs/inode.c | 4 ++++
fs/erofs/internal.h | 2 ++
3 files changed, 57 insertions(+)
diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c
index 23d7e862eed8..b3af72af7c88 100644
--- a/fs/erofs/fscache.c
+++ b/fs/erofs/fscache.c
@@ -83,10 +83,61 @@ static int erofs_fscache_meta_readpage(struct file *data,
struct page *page)
return ret;
}
+static int erofs_fscache_readpage(struct file *file, struct page *page)
+{
+ struct folio *folio = page_folio(page);
+ struct inode *inode = folio_mapping(folio)->host;
+ struct super_block *sb = inode->i_sb;
+ struct erofs_map_blocks map;
+ struct erofs_map_dev mdev;
+ erofs_off_t pos;
+ loff_t pstart;
+ int ret;
+
+ DBG_BUGON(folio_size(folio) != EROFS_BLKSIZ);
+
+ pos = folio_pos(folio);
+ map.m_la = pos;
+
+ ret = erofs_map_blocks(inode, &map, EROFS_GET_BLOCKS_RAW);
+ if (ret)
+ goto out_unlock;
+
+ if (!(map.m_flags & EROFS_MAP_MAPPED)) {
+ folio_zero_range(folio, 0, folio_size(folio));
+ goto out_uptodate;
+ }
+
+ mdev = (struct erofs_map_dev) {
+ .m_deviceid = map.m_deviceid,
+ .m_pa = map.m_pa,
+ };
+
+ ret = erofs_map_dev(sb, &mdev);
+ if (ret)
+ goto out_unlock;
+
+ pstart = mdev.m_pa + (pos - map.m_la);
+ ret = erofs_fscache_read_folios(mdev.m_fscache->cookie,
+ folio_mapping(folio), folio_pos(folio),
+ folio_size(folio), pstart);
+
+out_uptodate:
+ if (!ret)
+ folio_mark_uptodate(folio);
+out_unlock:
+ folio_unlock(folio);
+ return ret;
+}
+
static const struct address_space_operations erofs_fscache_meta_aops = {
.readpage = erofs_fscache_meta_readpage,
};
+const struct address_space_operations erofs_fscache_access_aops = {
+ .readpage = erofs_fscache_readpage,
+};
+
int erofs_fscache_register_cookie(struct super_block *sb,
struct erofs_fscache **fscache,
char *name, bool need_inode)
diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index e8b37ba5e9ad..8d3f56c6469b 100644
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -297,6 +297,10 @@ static int erofs_fill_inode(struct inode *inode, int isdir)
goto out_unlock;
}
inode->i_mapping->a_ops = &erofs_raw_access_aops;
+#ifdef CONFIG_EROFS_FS_ONDEMAND
+ if (erofs_is_fscache_mode(inode->i_sb))
+ inode->i_mapping->a_ops = &erofs_fscache_access_aops;
+#endif
out_unlock:
erofs_put_metabuf(&buf);
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index fa488af8dfcf..c8f6ac910976 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -639,6 +639,8 @@ int erofs_fscache_register_cookie(struct super_block *sb,
struct erofs_fscache **fscache,
char *name, bool need_inode);
void erofs_fscache_unregister_cookie(struct erofs_fscache **fscache);
+
+extern const struct address_space_operations erofs_fscache_access_aops;
#else
static inline int erofs_fscache_register_fs(struct super_block *sb)
{
--
2.27.0
--
Linux-cachefs mailing list
Linux-cachefs@redhat.com
https://listman.redhat.com/mailman/listinfo/linux-cachefs
