Re: [PATCH v2 1/6] ceph: disable old fscache readpage handling

[Xiubo Li <xiubli@redhat.com>]

On 2021/2/17 20:58, Jeff Layton wrote:
> With the new netfs read helper functions, we won't need a lot of this
> infrastructure as it handles the pagecache pages itself. Rip out the
> read handling for now, and much of the old infrastructure that deals in
> individual pages.
>
> The cookie handling is mostly unchanged, however.
>
> Signed-off-by: Jeff Layton <jlayton@kernel.org>
> Cc: ceph-devel@vger.kernel.org
> Cc: linux-cachefs@redhat.com
> Cc: linux-fsdevel@vger.kernel.org
> ---
>   fs/ceph/addr.c  |  31 +-----------
>   fs/ceph/cache.c | 125 ------------------------------------------------
>   fs/ceph/cache.h |  91 +----------------------------------
>   fs/ceph/caps.c  |   9 ----
>   4 files changed, 3 insertions(+), 253 deletions(-)
>
> diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
> index 950552944436..2b17bb36e548 100644
> --- a/fs/ceph/addr.c
> +++ b/fs/ceph/addr.c
> @@ -155,8 +155,6 @@ static void ceph_invalidatepage(struct page *page, unsigned int offset,
>   		return;
>   	}
>   
> -	ceph_invalidate_fscache_page(inode, page);
> -
>   	WARN_ON(!PageLocked(page));
>   	if (!PagePrivate(page))
>   		return;
> @@ -175,10 +173,6 @@ static int ceph_releasepage(struct page *page, gfp_t g)
>   	dout("%p releasepage %p idx %lu (%sdirty)\n", page->mapping->host,
>   	     page, page->index, PageDirty(page) ? "" : "not ");
>   
> -	/* Can we release the page from the cache? */
> -	if (!ceph_release_fscache_page(page, g))
> -		return 0;
> -
>   	return !PagePrivate(page);
>   }
>   
> @@ -213,10 +207,6 @@ static int ceph_do_readpage(struct file *filp, struct page *page)
>   		return 0;
>   	}
>   
> -	err = ceph_readpage_from_fscache(inode, page);
> -	if (err == 0)
> -		return -EINPROGRESS;
> -
>   	dout("readpage ino %llx.%llx file %p off %llu len %llu page %p index %lu\n",
>   	     vino.ino, vino.snap, filp, off, len, page, page->index);
>   	req = ceph_osdc_new_request(osdc, &ci->i_layout, vino, off, &len, 0, 1,
> @@ -241,7 +231,6 @@ static int ceph_do_readpage(struct file *filp, struct page *page)
>   	if (err == -ENOENT)
>   		err = 0;
>   	if (err < 0) {
> -		ceph_fscache_readpage_cancel(inode, page);
>   		if (err == -EBLOCKLISTED)
>   			fsc->blocklisted = true;
>   		goto out;
> @@ -253,8 +242,6 @@ static int ceph_do_readpage(struct file *filp, struct page *page)
>   		flush_dcache_page(page);
>   
>   	SetPageUptodate(page);
> -	ceph_readpage_to_fscache(inode, page);
> -
>   out:
>   	return err < 0 ? err : 0;
>   }
> @@ -294,10 +281,8 @@ static void finish_read(struct ceph_osd_request *req)
>   	for (i = 0; i < num_pages; i++) {
>   		struct page *page = osd_data->pages[i];
>   
> -		if (rc < 0 && rc != -ENOENT) {
> -			ceph_fscache_readpage_cancel(inode, page);
> +		if (rc < 0 && rc != -ENOENT)
>   			goto unlock;
> -		}
>   		if (bytes < (int)PAGE_SIZE) {
>   			/* zero (remainder of) page */
>   			int s = bytes < 0 ? 0 : bytes;
> @@ -307,7 +292,6 @@ static void finish_read(struct ceph_osd_request *req)
>   		     page->index);
>   		flush_dcache_page(page);
>   		SetPageUptodate(page);
> -		ceph_readpage_to_fscache(inode, page);
>   unlock:
>   		unlock_page(page);
>   		put_page(page);
> @@ -408,7 +392,6 @@ static int start_read(struct inode *inode, struct ceph_rw_context *rw_ctx,
>   		     page->index);
>   		if (add_to_page_cache_lru(page, &inode->i_data, page->index,
>   					  GFP_KERNEL)) {
> -			ceph_fscache_uncache_page(inode, page);
>   			put_page(page);
>   			dout("start_read %p add_to_page_cache failed %p\n",
>   			     inode, page);
> @@ -440,10 +423,8 @@ static int start_read(struct inode *inode, struct ceph_rw_context *rw_ctx,
>   	return nr_pages;
>   
>   out_pages:
> -	for (i = 0; i < nr_pages; ++i) {
> -		ceph_fscache_readpage_cancel(inode, pages[i]);
> +	for (i = 0; i < nr_pages; ++i)
>   		unlock_page(pages[i]);
> -	}
>   	ceph_put_page_vector(pages, nr_pages, false);
>   out_put:
>   	ceph_osdc_put_request(req);
> @@ -471,12 +452,6 @@ static int ceph_readpages(struct file *file, struct address_space *mapping,
>   	if (ceph_inode(inode)->i_inline_version != CEPH_INLINE_NONE)
>   		return -EINVAL;
>   
> -	rc = ceph_readpages_from_fscache(mapping->host, mapping, page_list,
> -					 &nr_pages);
> -
> -	if (rc == 0)
> -		goto out;
> -
>   	rw_ctx = ceph_find_rw_context(fi);
>   	max = fsc->mount_options->rsize >> PAGE_SHIFT;
>   	dout("readpages %p file %p ctx %p nr_pages %d max %d\n",
> @@ -487,8 +462,6 @@ static int ceph_readpages(struct file *file, struct address_space *mapping,
>   			goto out;
>   	}
>   out:
> -	ceph_fscache_readpages_cancel(inode, page_list);
> -
>   	dout("readpages %p file %p ret %d\n", inode, file, rc);
>   	return rc;
>   }
> diff --git a/fs/ceph/cache.c b/fs/ceph/cache.c
> index 2f5cb6bc78e1..9cfadbb86568 100644
> --- a/fs/ceph/cache.c
> +++ b/fs/ceph/cache.c
> @@ -173,7 +173,6 @@ void ceph_fscache_unregister_inode_cookie(struct ceph_inode_info* ci)
>   
>   	ci->fscache = NULL;
>   
> -	fscache_uncache_all_inode_pages(cookie, &ci->vfs_inode);
>   	fscache_relinquish_cookie(cookie, &ci->i_vino, false);
>   }
>   
> @@ -194,7 +193,6 @@ void ceph_fscache_file_set_cookie(struct inode *inode, struct file *filp)
>   		dout("fscache_file_set_cookie %p %p disabling cache\n",
>   		     inode, filp);
>   		fscache_disable_cookie(ci->fscache, &ci->i_vino, false);
> -		fscache_uncache_all_inode_pages(ci->fscache, inode);
>   	} else {
>   		fscache_enable_cookie(ci->fscache, &ci->i_vino, i_size_read(inode),
>   				      ceph_fscache_can_enable, inode);
> @@ -205,108 +203,6 @@ void ceph_fscache_file_set_cookie(struct inode *inode, struct file *filp)
>   	}
>   }
>   
> -static void ceph_readpage_from_fscache_complete(struct page *page, void *data, int error)
> -{
> -	if (!error)
> -		SetPageUptodate(page);
> -
> -	unlock_page(page);
> -}
> -
> -static inline bool cache_valid(struct ceph_inode_info *ci)
> -{
> -	return ci->i_fscache_gen == ci->i_rdcache_gen;
> -}
> -

Hi Jeff,

Please delete the "i_fscache_gen" member from the struct ceph_inode_info 
if we are not using it any more.

Thanks

Xiubo