From ef2c488c073f4f0b3a200745dd8d608c01d69c39 Mon Sep 17 00:00:00 2001 From: Anna Schumaker Date: Tue, 6 May 2014 09:12:36 -0400 Subject: NFS: Create a generic_pgio function These functions are almost identical on both the read and write side. FLUSH_COND_STABLE will never be set for the read path, so leaving it in the generic code won't hurt anything. Signed-off-by: Anna Schumaker Signed-off-by: Trond Myklebust --- fs/nfs/read.c | 81 +---------------------------------------------------------- 1 file changed, 1 insertion(+), 80 deletions(-) (limited to 'fs/nfs/read.c') diff --git a/fs/nfs/read.c b/fs/nfs/read.c index 64f8eefec76a..4fcef82d78b4 100644 --- a/fs/nfs/read.c +++ b/fs/nfs/read.c @@ -237,85 +237,6 @@ static const struct nfs_pgio_completion_ops nfs_async_read_completion_ops = { .completion = nfs_read_completion, }; -/* - * Generate multiple requests to fill a single page. - * - * We optimize to reduce the number of read operations on the wire. If we - * detect that we're reading a page, or an area of a page, that is past the - * end of file, we do not generate NFS read operations but just clear the - * parts of the page that would have come back zero from the server anyway. - * - * We rely on the cached value of i_size to make this determination; another - * client can fill pages on the server past our cached end-of-file, but we - * won't see the new data until our attribute cache is updated. This is more - * or less conventional NFS client behavior. - */ -static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc, - struct nfs_pgio_header *hdr) -{ - struct nfs_page *req = hdr->req; - struct page *page = req->wb_page; - struct nfs_pgio_data *data; - size_t rsize = desc->pg_bsize, nbytes; - unsigned int offset; - - offset = 0; - nbytes = desc->pg_count; - do { - size_t len = min(nbytes,rsize); - - data = nfs_pgio_data_alloc(hdr, 1); - if (!data) - return nfs_pgio_error(desc, hdr); - data->pages.pagevec[0] = page; - nfs_pgio_rpcsetup(data, len, offset, 0, NULL); - list_add(&data->list, &hdr->rpc_list); - nbytes -= len; - offset += len; - } while (nbytes != 0); - - nfs_list_remove_request(req); - nfs_list_add_request(req, &hdr->pages); - desc->pg_rpc_callops = &nfs_pgio_common_ops; - return 0; -} - -static int nfs_pagein_one(struct nfs_pageio_descriptor *desc, - struct nfs_pgio_header *hdr) -{ - struct nfs_page *req; - struct page **pages; - struct nfs_pgio_data *data; - struct list_head *head = &desc->pg_list; - - data = nfs_pgio_data_alloc(hdr, nfs_page_array_len(desc->pg_base, - desc->pg_count)); - if (!data) - return nfs_pgio_error(desc, hdr); - - pages = data->pages.pagevec; - while (!list_empty(head)) { - req = nfs_list_entry(head->next); - nfs_list_remove_request(req); - nfs_list_add_request(req, &hdr->pages); - *pages++ = req->wb_page; - } - - nfs_pgio_rpcsetup(data, desc->pg_count, 0, 0, NULL); - list_add(&data->list, &hdr->rpc_list); - desc->pg_rpc_callops = &nfs_pgio_common_ops; - return 0; -} - -int nfs_generic_pagein(struct nfs_pageio_descriptor *desc, - struct nfs_pgio_header *hdr) -{ - if (desc->pg_bsize < PAGE_CACHE_SIZE) - return nfs_pagein_multi(desc, hdr); - return nfs_pagein_one(desc, hdr); -} -EXPORT_SYMBOL_GPL(nfs_generic_pagein); - static int nfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc) { struct nfs_rw_header *rhdr; @@ -330,7 +251,7 @@ static int nfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc) hdr = &rhdr->header; nfs_pgheader_init(desc, hdr, nfs_rw_header_free); atomic_inc(&hdr->refcnt); - ret = nfs_generic_pagein(desc, hdr); + ret = nfs_generic_pgio(desc, hdr); if (ret == 0) ret = nfs_do_multiple_reads(&hdr->rpc_list, desc->pg_rpc_callops); -- cgit v1.2.3