From: Weston Andros Adamson Date: Thu, 15 May 2014 15:56:43 +0000 (-0400) Subject: nfs: modify pg_test interface to return size_t X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=b4fdac1a5150174df0847a45dc6612ce5ce3daeb;p=deliverable%2Flinux.git nfs: modify pg_test interface to return size_t This is a step toward allowing pg_test to inform the the coalescing code to reduce the size of requests so they may fit in whatever scheme the pg_test callback wants to define. For now, just return the size of the request if there is space, or 0 if there is not. This shouldn't change any behavior as it acts the same as when the pg_test functions returned bool. Signed-off-by: Weston Andros Adamson Signed-off-by: Trond Myklebust --- diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c index 206cc68c9694..9b431f44fad9 100644 --- a/fs/nfs/blocklayout/blocklayout.c +++ b/fs/nfs/blocklayout/blocklayout.c @@ -1189,13 +1189,17 @@ bl_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req) pnfs_generic_pg_init_read(pgio, req); } -static bool +/* + * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number + * of bytes (maximum @req->wb_bytes) that can be coalesced. + */ +static size_t bl_pg_test_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req) { if (pgio->pg_dreq != NULL && !is_aligned_req(req, SECTOR_SIZE)) - return false; + return 0; return pnfs_generic_pg_test(pgio, prev, req); } @@ -1241,13 +1245,17 @@ bl_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req) } } -static bool +/* + * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number + * of bytes (maximum @req->wb_bytes) that can be coalesced. + */ +static size_t bl_pg_test_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req) { if (pgio->pg_dreq != NULL && !is_aligned_req(req, PAGE_CACHE_SIZE)) - return false; + return 0; return pnfs_generic_pg_test(pgio, prev, req); } diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c index 9fd7cebbff04..ba9a9aadf6c8 100644 --- a/fs/nfs/nfs4filelayout.c +++ b/fs/nfs/nfs4filelayout.c @@ -915,10 +915,10 @@ filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid, /* * filelayout_pg_test(). Called by nfs_can_coalesce_requests() * - * return true : coalesce page - * return false : don't coalesce page + * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number + * of bytes (maximum @req->wb_bytes) that can be coalesced. */ -static bool +static size_t filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req) { @@ -927,7 +927,7 @@ filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, if (!pnfs_generic_pg_test(pgio, prev, req) || !nfs_generic_pg_test(pgio, prev, req)) - return false; + return 0; p_stripe = (u64)req_offset(prev); r_stripe = (u64)req_offset(req); @@ -936,7 +936,9 @@ filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, do_div(p_stripe, stripe_unit); do_div(r_stripe, stripe_unit); - return (p_stripe == r_stripe); + if (p_stripe == r_stripe) + return req->wb_bytes; + return 0; } static void diff --git a/fs/nfs/objlayout/objio_osd.c b/fs/nfs/objlayout/objio_osd.c index 426b366b0b33..71b9c69dbe9c 100644 --- a/fs/nfs/objlayout/objio_osd.c +++ b/fs/nfs/objlayout/objio_osd.c @@ -564,14 +564,19 @@ int objio_write_pagelist(struct nfs_pgio_data *wdata, int how) return 0; } -static bool objio_pg_test(struct nfs_pageio_descriptor *pgio, +/* + * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number + * of bytes (maximum @req->wb_bytes) that can be coalesced. + */ +static size_t objio_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req) { - if (!pnfs_generic_pg_test(pgio, prev, req)) - return false; + if (!pnfs_generic_pg_test(pgio, prev, req) || + pgio->pg_count + req->wb_bytes > + (unsigned long)pgio->pg_layout_private) + return 0; - return pgio->pg_count + req->wb_bytes <= - (unsigned long)pgio->pg_layout_private; + return req->wb_bytes; } static void objio_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req) diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c index 4b4b212ec6b2..82233431880d 100644 --- a/fs/nfs/pagelist.c +++ b/fs/nfs/pagelist.c @@ -280,7 +280,17 @@ nfs_wait_on_request(struct nfs_page *req) TASK_UNINTERRUPTIBLE); } -bool nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, struct nfs_page *prev, struct nfs_page *req) +/* + * nfs_generic_pg_test - determine if requests can be coalesced + * @desc: pointer to descriptor + * @prev: previous request in desc, or NULL + * @req: this request + * + * Returns zero if @req can be coalesced into @desc, otherwise it returns + * the size of the request. + */ +size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, + struct nfs_page *prev, struct nfs_page *req) { /* * FIXME: ideally we should be able to coalesce all requests @@ -292,7 +302,9 @@ bool nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, struct nfs_page *pr if (desc->pg_bsize < PAGE_SIZE) return 0; - return desc->pg_count + req->wb_bytes <= desc->pg_bsize; + if (desc->pg_count + req->wb_bytes <= desc->pg_bsize) + return req->wb_bytes; + return 0; } EXPORT_SYMBOL_GPL(nfs_generic_pg_test); @@ -747,6 +759,8 @@ static bool nfs_can_coalesce_requests(struct nfs_page *prev, struct nfs_page *req, struct nfs_pageio_descriptor *pgio) { + size_t size; + if (!nfs_match_open_context(req->wb_context, prev->wb_context)) return false; if (req->wb_context->dentry->d_inode->i_flock != NULL && @@ -758,7 +772,9 @@ static bool nfs_can_coalesce_requests(struct nfs_page *prev, return false; if (req_offset(req) != req_offset(prev) + prev->wb_bytes) return false; - return pgio->pg_ops->pg_test(pgio, prev, req); + size = pgio->pg_ops->pg_test(pgio, prev, req); + WARN_ON_ONCE(size && size != req->wb_bytes); + return size > 0; } /** diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 0fe670189fd1..de6eb16f94d1 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -1434,7 +1434,11 @@ pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio, } EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write); -bool +/* + * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number + * of bytes (maximum @req->wb_bytes) that can be coalesced. + */ +size_t pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req) { @@ -1455,8 +1459,10 @@ pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, * first byte that lies outside the pnfs_layout_range. FIXME? * */ - return req_offset(req) < end_offset(pgio->pg_lseg->pls_range.offset, - pgio->pg_lseg->pls_range.length); + if (req_offset(req) < end_offset(pgio->pg_lseg->pls_range.offset, + pgio->pg_lseg->pls_range.length)) + return req->wb_bytes; + return 0; } EXPORT_SYMBOL_GPL(pnfs_generic_pg_test); diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h index 0031267d7492..dccf182ec4d8 100644 --- a/fs/nfs/pnfs.h +++ b/fs/nfs/pnfs.h @@ -187,7 +187,8 @@ int pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc); void pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req, u64 wb_size); int pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc); -bool pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req); +size_t pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, + struct nfs_page *prev, struct nfs_page *req); void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg); struct pnfs_layout_segment *pnfs_layout_process(struct nfs4_layoutget *lgp); void pnfs_free_lseg_list(struct list_head *tmp_list); diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h index be0b0981e7a0..13d59af561f6 100644 --- a/include/linux/nfs_page.h +++ b/include/linux/nfs_page.h @@ -46,7 +46,8 @@ struct nfs_page { struct nfs_pageio_descriptor; struct nfs_pageio_ops { void (*pg_init)(struct nfs_pageio_descriptor *, struct nfs_page *); - bool (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, struct nfs_page *); + size_t (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, + struct nfs_page *); int (*pg_doio)(struct nfs_pageio_descriptor *); }; @@ -102,7 +103,7 @@ extern int nfs_pageio_add_request(struct nfs_pageio_descriptor *, struct nfs_page *); extern void nfs_pageio_complete(struct nfs_pageio_descriptor *desc); extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *, pgoff_t); -extern bool nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, +extern size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, struct nfs_page *prev, struct nfs_page *req); extern int nfs_wait_on_request(struct nfs_page *);