This patch implements the data plane of reading data from data blob file
over fscache.
Signed-off-by: Jeffle Xu <jeffl...@linux.alibaba.com>
---
fs/erofs/data.c | 3 +++
fs/erofs/fscache.c | 25 +++++++++++++++++++++++--
fs/erofs/internal.h | 1 +
3 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/fs/erofs/data.c b/fs/erofs/data.c
index f0857c285fac..621769ab5753 100644
--- a/fs/erofs/data.c
+++ b/fs/erofs/data.c
@@ -166,6 +166,7 @@ int erofs_map_dev(struct super_block *sb, struct
erofs_map_dev *map)
/* primary device by default */
map->m_bdev = sb->s_bdev;
map->m_daxdev = EROFS_SB(sb)->dax_dev;
+ map->m_ctx = EROFS_SB(sb)->bootstrap;
if (map->m_deviceid) {
down_read(&devs->rwsem);
@@ -176,6 +177,7 @@ int erofs_map_dev(struct super_block *sb, struct
erofs_map_dev *map)
}
map->m_bdev = dif->bdev;
map->m_daxdev = dif->dax_dev;
+ map->m_ctx = dif->ctx;
up_read(&devs->rwsem);
} else if (devs->extra_devices) {
down_read(&devs->rwsem);
@@ -192,6 +194,7 @@ int erofs_map_dev(struct super_block *sb, struct
erofs_map_dev *map)
map->m_pa -= startoff;
map->m_bdev = dif->bdev;
map->m_daxdev = dif->dax_dev;
+ map->m_ctx = dif->ctx;
break;
}
}
diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c
index bfcec831d58a..7d4f6682e521 100644
--- a/fs/erofs/fscache.c
+++ b/fs/erofs/fscache.c
@@ -77,12 +77,24 @@ static inline void do_copy_page(struct page *from, struct
page *to,
kunmap_atomic(vfrom);
}
+static struct page *erofs_fscache_get_page(struct erofs_cookie_ctx *ctx,
+ erofs_blk_t blkaddr)
+{
+ struct page *page;
+
+ page = erofs_readpage_from_fscache(ctx, blkaddr);
+ if (!IS_ERR(page))
+ lock_page(page);
+ return page;
+}
+
static int erofs_fscache_do_readpage(struct file *file, struct page *page)
{
struct inode *inode = page->mapping->host;
struct erofs_inode *vi = EROFS_I(inode);
struct super_block *sb = inode->i_sb;
struct erofs_map_blocks map;
+ struct erofs_map_dev mdev;
erofs_off_t o_la, pa;
size_t offset, len;
struct page *ipage;
@@ -105,6 +117,15 @@ static int erofs_fscache_do_readpage(struct file *file,
struct page *page)
return 0;
}
+ mdev = (struct erofs_map_dev) {
+ .m_deviceid = map.m_deviceid,
+ .m_pa = map.m_pa,
+ };
+
+ ret = erofs_map_dev(inode->i_sb, &mdev);
+ if (ret)
+ return ret;
+
/*
* 1) For FLAT_PLAIN/FLAT_INLINE layout, the output map.m_la shall be
* equal to o_la, and the output map.m_pa is exactly the physical
@@ -114,9 +135,9 @@ static int erofs_fscache_do_readpage(struct file *file,
struct page *page)
* physical address of this chunk boundary. So we need to recalculate
* the actual physical address of o_la.
*/
- pa = map.m_pa + o_la - map.m_la;
+ pa = mdev.m_pa + o_la - map.m_la;
- ipage = erofs_get_meta_page(sb, erofs_blknr(pa));
+ ipage = erofs_fscache_get_page(mdev.m_ctx, erofs_blknr(pa));
if (IS_ERR(ipage))
return PTR_ERR(ipage);
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index f60577a7aade..b21c3751e88d 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -447,6 +447,7 @@ static inline int z_erofs_map_blocks_iter(struct inode
*inode,
struct erofs_map_dev {
struct block_device *m_bdev;
struct dax_device *m_daxdev;
+ struct erofs_cookie_ctx *m_ctx;
erofs_off_t m_pa;
unsigned int m_deviceid;
--
2.27.0
--
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