Re: [PATCH] staging: erofs: clean up erofs_map_blocks_iter

From: Gao Xiang
Date: Wed Jan 09 2019 - 06:54:42 EST


Hi Chao,

On 2019/1/9 17:46, Chao Yu wrote:
> This patch cleans up erofs_map_blocks* function and structure family,
> just simply the code, no logic change.
>
> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
> ---
> drivers/staging/erofs/data.c | 40 +++++++------------------------
> drivers/staging/erofs/internal.h | 16 ++++++-------
> drivers/staging/erofs/unzip_vle.c | 30 +++++++++++------------
> 3 files changed, 31 insertions(+), 55 deletions(-)
>
> diff --git a/drivers/staging/erofs/data.c b/drivers/staging/erofs/data.c
> index 5a55f0bfdfbb..1baa59cf11b5 100644
> --- a/drivers/staging/erofs/data.c
> +++ b/drivers/staging/erofs/data.c
> @@ -165,43 +165,19 @@ static int erofs_map_blocks_flatmode(struct inode *inode,
> return err;
> }
>
> -#ifdef CONFIG_EROFS_FS_ZIP
> -extern int z_erofs_map_blocks_iter(struct inode *,
> - struct erofs_map_blocks *,
> - struct page **, int);
> -#endif
> -
> -int erofs_map_blocks_iter(struct inode *inode,
> - struct erofs_map_blocks *map,
> - struct page **mpage_ret, int flags)
> -{
> - /* by default, reading raw data never use erofs_map_blocks_iter */
> - if (unlikely(!is_inode_layout_compression(inode))) {
> - if (*mpage_ret)
> - put_page(*mpage_ret);
> - *mpage_ret = NULL;
> -
> - return erofs_map_blocks(inode, map, flags);
> - }
> -
> -#ifdef CONFIG_EROFS_FS_ZIP
> - return z_erofs_map_blocks_iter(inode, map, mpage_ret, flags);
> -#else
> - /* data compression is not available */
> - return -ENOTSUPP;
> -#endif
> -}
> -
> int erofs_map_blocks(struct inode *inode,
> struct erofs_map_blocks *map, int flags)
> {
> if (unlikely(is_inode_layout_compression(inode))) {
> - struct page *mpage = NULL;
> - int err;
> + int err = -ENOTSUPP;
>
> - err = erofs_map_blocks_iter(inode, map, &mpage, flags);
> - if (mpage)
> - put_page(mpage);
> +#ifdef CONFIG_EROFS_FS_ZIP
> + map->mpage = NULL;

remove this line? since z_erofs_map_blocks_iter will do put_page internally
if mpage != NULL.

> +
> + err = z_erofs_map_blocks_iter(inode, map, flags);
> +#endif
> + if (map->mpage)
> + put_page(map->mpage);


if (map->mpage) {
put_page(map->mpage);
map->mpage = NULL;
}


> return err;
> }
> return erofs_map_blocks_flatmode(inode, map, flags);
> diff --git a/drivers/staging/erofs/internal.h b/drivers/staging/erofs/internal.h
> index e049d00c087a..740961fc565f 100644
> --- a/drivers/staging/erofs/internal.h
> +++ b/drivers/staging/erofs/internal.h
> @@ -461,8 +461,16 @@ struct erofs_map_blocks {
> u64 m_plen, m_llen;
>
> unsigned int m_flags;
> +
> + struct page *mpage;
> };
>
> +#ifdef CONFIG_EROFS_FS_ZIP
> +extern int z_erofs_map_blocks_iter(struct inode *,
> + struct erofs_map_blocks *,
> + int);

#else

static inline z_erofs_map_blocks_iter(struct inode *, ...) { return -ENOTSUPP;}

--- therefore redundant CONFIG_EROFS_FS_ZIPs could be removed.

#endif

> +#endif
> +
> /* Flags used by erofs_map_blocks() */
> #define EROFS_GET_BLOCKS_RAW 0x0001
>
> @@ -522,14 +530,6 @@ static inline struct page *erofs_get_meta_page_nofail(struct super_block *sb,
> }
>
> extern int erofs_map_blocks(struct inode *, struct erofs_map_blocks *, int);
> -extern int erofs_map_blocks_iter(struct inode *, struct erofs_map_blocks *,
> - struct page **, int);
> -
> -struct erofs_map_blocks_iter {
> - struct erofs_map_blocks map;
> - struct page *mpage;
> -};
> -
>
> static inline struct page *
> erofs_get_inline_page(struct inode *inode,
> diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c
> index 4ac1099a39c6..30340afaa504 100644
> --- a/drivers/staging/erofs/unzip_vle.c
> +++ b/drivers/staging/erofs/unzip_vle.c
> @@ -636,7 +636,7 @@ struct z_erofs_vle_frontend {
> struct inode *const inode;
>
> struct z_erofs_vle_work_builder builder;
> - struct erofs_map_blocks_iter m_iter;
> + struct erofs_map_blocks map;
>
> z_erofs_vle_owned_workgrp_t owned_head;
>
> @@ -647,8 +647,9 @@ struct z_erofs_vle_frontend {
>
> #define VLE_FRONTEND_INIT(__i) { \
> .inode = __i, \
> - .m_iter = { \
> - { .m_llen = 0, .m_plen = 0 }, \
> + .map = { \
> + .m_llen = 0, \
> + .m_plen = 0, \
> .mpage = NULL \
> }, \
> .builder = VLE_WORK_BUILDER_INIT(), \
> @@ -681,8 +682,7 @@ static int z_erofs_do_read_page(struct z_erofs_vle_frontend *fe,
> {
> struct super_block *const sb = fe->inode->i_sb;
> struct erofs_sb_info *const sbi __maybe_unused = EROFS_SB(sb);
> - struct erofs_map_blocks_iter *const m = &fe->m_iter;
> - struct erofs_map_blocks *const map = &m->map;
> + struct erofs_map_blocks *const map = &fe->map;
> struct z_erofs_vle_work_builder *const builder = &fe->builder;
> const loff_t offset = page_offset(page);
>
> @@ -715,7 +715,7 @@ static int z_erofs_do_read_page(struct z_erofs_vle_frontend *fe,
>
> map->m_la = offset + cur;
> map->m_llen = 0;
> - err = erofs_map_blocks_iter(fe->inode, map, &m->mpage, 0);
> + err = erofs_map_blocks(fe->inode, map, 0);

should use z_erofs_map_blocks_iter then rather than erofs_map_blocks

Thanks,
Gao Xiang

> if (unlikely(err))
> goto err_out;
>
> @@ -1484,8 +1484,8 @@ static int z_erofs_vle_normalaccess_readpage(struct file *file,
>
> z_erofs_submit_and_unzip(&f, &pagepool, true);
> out:
> - if (f.m_iter.mpage)
> - put_page(f.m_iter.mpage);
> + if (f.map.mpage)
> + put_page(f.map.mpage);
>
> /* clean up the remaining free pages */
> put_pages_list(&pagepool);
> @@ -1555,8 +1555,8 @@ static int z_erofs_vle_normalaccess_readpages(struct file *filp,
>
> z_erofs_submit_and_unzip(&f, &pagepool, sync);
>
> - if (f.m_iter.mpage)
> - put_page(f.m_iter.mpage);
> + if (f.map.mpage)
> + put_page(f.map.mpage);
>
> /* clean up the remaining free pages */
> put_pages_list(&pagepool);
> @@ -1701,14 +1701,14 @@ vle_get_logical_extent_head(const struct vle_map_blocks_iter_ctx *ctx,
>
> int z_erofs_map_blocks_iter(struct inode *inode,
> struct erofs_map_blocks *map,
> - struct page **mpage_ret, int flags)
> + int flags)
> {
> void *kaddr;
> const struct vle_map_blocks_iter_ctx ctx = {
> .inode = inode,
> .sb = inode->i_sb,
> .clusterbits = EROFS_I_SB(inode)->clusterbits,
> - .mpage_ret = mpage_ret,
> + .mpage_ret = &map->mpage,
> .kaddr_ret = &kaddr
> };
> const unsigned int clustersize = 1 << ctx.clusterbits;
> @@ -1722,7 +1722,7 @@ int z_erofs_map_blocks_iter(struct inode *inode,
>
> /* initialize `pblk' to keep gcc from printing foolish warnings */
> erofs_blk_t mblk, pblk = 0;
> - struct page *mpage = *mpage_ret;
> + struct page *mpage = map->mpage;
> struct z_erofs_vle_decompressed_index *di;
> unsigned int cluster_type, logical_cluster_ofs;
> int err = 0;
> @@ -1758,7 +1758,7 @@ int z_erofs_map_blocks_iter(struct inode *inode,
> err = PTR_ERR(mpage);
> goto out;
> }
> - *mpage_ret = mpage;
> + map->mpage = mpage;
> } else {
> lock_page(mpage);
> DBG_BUGON(!PageUptodate(mpage));
> @@ -1818,7 +1818,7 @@ int z_erofs_map_blocks_iter(struct inode *inode,
> /* get the correspoinding first chunk */
> err = vle_get_logical_extent_head(&ctx, lcn, &ofs,
> &pblk, &map->m_flags);
> - mpage = *mpage_ret;
> + mpage = map->mpage;
>
> if (unlikely(err)) {
> if (mpage)
>