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 <dros@xxxxxxxxxxxxxxx>
---
fs/nfs/blocklayout/blocklayout.c | 16 ++++++++++++----
fs/nfs/nfs4filelayout.c | 12 +++++++-----
fs/nfs/objlayout/objio_osd.c | 15 ++++++++++-----
fs/nfs/pagelist.c | 22 +++++++++++++++++++---
fs/nfs/pnfs.c | 12 +++++++++---
fs/nfs/pnfs.h | 3 ++-
include/linux/nfs_page.h | 5 +++--
7 files changed, 62 insertions(+), 23 deletions(-)
diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index 206cc68..9b431f4 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 9fd7ceb..ba9a9aa 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 426b366..71b9c69 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 30c221c..4cd7a2a 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -277,7 +277,17 @@ 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
@@ -289,7 +299,9 @@ 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);
@@ -356,6 +368,8 @@ 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 &&
@@ -367,7 +381,9 @@ 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 0fe6701..de6eb16 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 0031267..dccf182 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 8cb2640..40faddd 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 *);
--
1.8.5.2 (Apple Git-48)
--
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