nfs: add mirroring support to pgio layer
This patch adds mirrored write support to the pgio layer. The default
is to use one mirror, but pgio callers may define callbacks to change
this to any value up to the (arbitrarily selected) limit of 16.
The basic idea is to break out members of nfs_pageio_descriptor that cannot
be shared between mirrored DSes and put them in a new structure.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 1ee41d7..0178d4f 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -360,8 +360,14 @@
spin_lock(&dreq->lock);
if (test_bit(NFS_IOHDR_ERROR, &hdr->flags) && (hdr->good_bytes == 0))
dreq->error = hdr->error;
- else
- dreq->count += hdr->good_bytes;
+ else {
+ /*
+ * FIXME: right now this only accounts for bytes written
+ * to the first mirror
+ */
+ if (hdr->pgio_mirror_idx == 0)
+ dreq->count += hdr->good_bytes;
+ }
spin_unlock(&dreq->lock);
while (!list_empty(&hdr->pages)) {
@@ -724,7 +730,12 @@
dreq->error = hdr->error;
}
if (dreq->error == 0) {
- dreq->count += hdr->good_bytes;
+ /*
+ * FIXME: right now this only accounts for bytes written
+ * to the first mirror
+ */
+ if (hdr->pgio_mirror_idx == 0)
+ dreq->count += hdr->good_bytes;
if (nfs_write_need_commit(hdr)) {
if (dreq->flags == NFS_ODIRECT_RESCHED_WRITES)
request_commit = true;
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 05f9a87..ef1c703 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -469,6 +469,7 @@
struct nfs_direct_req *dreq);
int nfs_key_timeout_notify(struct file *filp, struct inode *inode);
bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx);
+void nfs_pageio_stop_mirroring(struct nfs_pageio_descriptor *pgio);
#ifdef CONFIG_MIGRATION
extern int nfs_migrate_page(struct address_space *,
diff --git a/fs/nfs/objlayout/objio_osd.c b/fs/nfs/objlayout/objio_osd.c
index d007780..9a5f2ee 100644
--- a/fs/nfs/objlayout/objio_osd.c
+++ b/fs/nfs/objlayout/objio_osd.c
@@ -537,11 +537,12 @@
static size_t objio_pg_test(struct nfs_pageio_descriptor *pgio,
struct nfs_page *prev, struct nfs_page *req)
{
+ struct nfs_pgio_mirror *mirror = &pgio->pg_mirrors[pgio->pg_mirror_idx];
unsigned int size;
size = pnfs_generic_pg_test(pgio, prev, req);
- if (!size || pgio->pg_count + req->wb_bytes >
+ if (!size || mirror->pg_count + req->wb_bytes >
(unsigned long)pgio->pg_layout_private)
return 0;
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 1c03187..eec12b7 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -46,17 +46,22 @@
struct nfs_pgio_header *hdr,
void (*release)(struct nfs_pgio_header *hdr))
{
- hdr->req = nfs_list_entry(desc->pg_list.next);
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
+
+ hdr->req = nfs_list_entry(mirror->pg_list.next);
hdr->inode = desc->pg_inode;
hdr->cred = hdr->req->wb_context->cred;
hdr->io_start = req_offset(hdr->req);
- hdr->good_bytes = desc->pg_count;
+ hdr->good_bytes = mirror->pg_count;
hdr->dreq = desc->pg_dreq;
hdr->layout_private = desc->pg_layout_private;
hdr->release = release;
hdr->completion_ops = desc->pg_completion_ops;
if (hdr->completion_ops->init_hdr)
hdr->completion_ops->init_hdr(hdr);
+
+ hdr->pgio_mirror_idx = desc->pg_mirror_idx;
}
EXPORT_SYMBOL_GPL(nfs_pgheader_init);
@@ -480,7 +485,10 @@
size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc,
struct nfs_page *prev, struct nfs_page *req)
{
- if (desc->pg_count > desc->pg_bsize) {
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
+
+ if (mirror->pg_count > mirror->pg_bsize) {
/* should never happen */
WARN_ON_ONCE(1);
return 0;
@@ -490,11 +498,11 @@
* Limit the request size so that we can still allocate a page array
* for it without upsetting the slab allocator.
*/
- if (((desc->pg_count + req->wb_bytes) >> PAGE_SHIFT) *
+ if (((mirror->pg_count + req->wb_bytes) >> PAGE_SHIFT) *
sizeof(struct page) > PAGE_SIZE)
return 0;
- return min(desc->pg_bsize - desc->pg_count, (size_t)req->wb_bytes);
+ return min(mirror->pg_bsize - mirror->pg_count, (size_t)req->wb_bytes);
}
EXPORT_SYMBOL_GPL(nfs_generic_pg_test);
@@ -651,10 +659,18 @@
static int nfs_pgio_error(struct nfs_pageio_descriptor *desc,
struct nfs_pgio_header *hdr)
{
+ struct nfs_pgio_mirror *mirror;
+ u32 midx;
+
set_bit(NFS_IOHDR_REDO, &hdr->flags);
nfs_pgio_data_destroy(hdr);
hdr->completion_ops->completion(hdr);
- desc->pg_completion_ops->error_cleanup(&desc->pg_list);
+ /* TODO: Make sure it's right to clean up all mirrors here
+ * and not just hdr->pgio_mirror_idx */
+ for (midx = 0; midx < desc->pg_mirror_count; midx++) {
+ mirror = &desc->pg_mirrors[midx];
+ desc->pg_completion_ops->error_cleanup(&mirror->pg_list);
+ }
return -ENOMEM;
}
@@ -671,6 +687,17 @@
hdr->completion_ops->completion(hdr);
}
+static void nfs_pageio_mirror_init(struct nfs_pgio_mirror *mirror,
+ unsigned int bsize)
+{
+ INIT_LIST_HEAD(&mirror->pg_list);
+ mirror->pg_bytes_written = 0;
+ mirror->pg_count = 0;
+ mirror->pg_bsize = bsize;
+ mirror->pg_base = 0;
+ mirror->pg_recoalesce = 0;
+}
+
/**
* nfs_pageio_init - initialise a page io descriptor
* @desc: pointer to descriptor
@@ -687,13 +714,10 @@
size_t bsize,
int io_flags)
{
- INIT_LIST_HEAD(&desc->pg_list);
- desc->pg_bytes_written = 0;
- desc->pg_count = 0;
- desc->pg_bsize = bsize;
- desc->pg_base = 0;
+ struct nfs_pgio_mirror *new;
+ int i;
+
desc->pg_moreio = 0;
- desc->pg_recoalesce = 0;
desc->pg_inode = inode;
desc->pg_ops = pg_ops;
desc->pg_completion_ops = compl_ops;
@@ -703,6 +727,26 @@
desc->pg_lseg = NULL;
desc->pg_dreq = NULL;
desc->pg_layout_private = NULL;
+ desc->pg_bsize = bsize;
+
+ desc->pg_mirror_count = 1;
+ desc->pg_mirror_idx = 0;
+
+ if (pg_ops->pg_get_mirror_count) {
+ /* until we have a request, we don't have an lseg and no
+ * idea how many mirrors there will be */
+ new = kcalloc(NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX,
+ sizeof(struct nfs_pgio_mirror), GFP_KERNEL);
+ desc->pg_mirrors_dynamic = new;
+ desc->pg_mirrors = new;
+
+ for (i = 0; i < NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX; i++)
+ nfs_pageio_mirror_init(&desc->pg_mirrors[i], bsize);
+ } else {
+ desc->pg_mirrors_dynamic = NULL;
+ desc->pg_mirrors = desc->pg_mirrors_static;
+ nfs_pageio_mirror_init(&desc->pg_mirrors[0], bsize);
+ }
}
EXPORT_SYMBOL_GPL(nfs_pageio_init);
@@ -738,14 +782,16 @@
int nfs_generic_pgio(struct nfs_pageio_descriptor *desc,
struct nfs_pgio_header *hdr)
{
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
struct nfs_page *req;
struct page **pages,
*last_page;
- struct list_head *head = &desc->pg_list;
+ struct list_head *head = &mirror->pg_list;
struct nfs_commit_info cinfo;
unsigned int pagecount, pageused;
- pagecount = nfs_page_array_len(desc->pg_base, desc->pg_count);
+ pagecount = nfs_page_array_len(mirror->pg_base, mirror->pg_count);
if (!nfs_pgarray_set(&hdr->page_array, pagecount))
return nfs_pgio_error(desc, hdr);
@@ -773,7 +819,7 @@
desc->pg_ioflags &= ~FLUSH_COND_STABLE;
/* Set up the argument struct */
- nfs_pgio_rpcsetup(hdr, desc->pg_count, 0, desc->pg_ioflags, &cinfo);
+ nfs_pgio_rpcsetup(hdr, mirror->pg_count, 0, desc->pg_ioflags, &cinfo);
desc->pg_rpc_callops = &nfs_pgio_common_ops;
return 0;
}
@@ -781,12 +827,17 @@
static int nfs_generic_pg_pgios(struct nfs_pageio_descriptor *desc)
{
+ struct nfs_pgio_mirror *mirror;
struct nfs_pgio_header *hdr;
int ret;
+ mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
if (!hdr) {
- desc->pg_completion_ops->error_cleanup(&desc->pg_list);
+ /* TODO: make sure this is right with mirroring - or
+ * should it back out all mirrors? */
+ desc->pg_completion_ops->error_cleanup(&mirror->pg_list);
return -ENOMEM;
}
nfs_pgheader_init(desc, hdr, nfs_pgio_header_free);
@@ -801,6 +852,49 @@
return ret;
}
+/*
+ * nfs_pageio_setup_mirroring - determine if mirroring is to be used
+ * by calling the pg_get_mirror_count op
+ */
+static int nfs_pageio_setup_mirroring(struct nfs_pageio_descriptor *pgio,
+ struct nfs_page *req)
+{
+ int mirror_count = 1;
+
+ if (!pgio->pg_ops->pg_get_mirror_count)
+ return 0;
+
+ mirror_count = pgio->pg_ops->pg_get_mirror_count(pgio, req);
+
+ if (!mirror_count || mirror_count > NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX)
+ return -EINVAL;
+
+ if (WARN_ON_ONCE(!pgio->pg_mirrors_dynamic))
+ return -EINVAL;
+
+ pgio->pg_mirror_count = mirror_count;
+
+ return 0;
+}
+
+/*
+ * nfs_pageio_stop_mirroring - stop using mirroring (set mirror count to 1)
+ */
+void nfs_pageio_stop_mirroring(struct nfs_pageio_descriptor *pgio)
+{
+ pgio->pg_mirror_count = 1;
+ pgio->pg_mirror_idx = 0;
+}
+
+static void nfs_pageio_cleanup_mirroring(struct nfs_pageio_descriptor *pgio)
+{
+ pgio->pg_mirror_count = 1;
+ pgio->pg_mirror_idx = 0;
+ pgio->pg_mirrors = pgio->pg_mirrors_static;
+ kfree(pgio->pg_mirrors_dynamic);
+ pgio->pg_mirrors_dynamic = NULL;
+}
+
static bool nfs_match_open_context(const struct nfs_open_context *ctx1,
const struct nfs_open_context *ctx2)
{
@@ -867,19 +961,22 @@
static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc,
struct nfs_page *req)
{
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
struct nfs_page *prev = NULL;
- if (desc->pg_count != 0) {
- prev = nfs_list_entry(desc->pg_list.prev);
+
+ if (mirror->pg_count != 0) {
+ prev = nfs_list_entry(mirror->pg_list.prev);
} else {
if (desc->pg_ops->pg_init)
desc->pg_ops->pg_init(desc, req);
- desc->pg_base = req->wb_pgbase;
+ mirror->pg_base = req->wb_pgbase;
}
if (!nfs_can_coalesce_requests(prev, req, desc))
return 0;
nfs_list_remove_request(req);
- nfs_list_add_request(req, &desc->pg_list);
- desc->pg_count += req->wb_bytes;
+ nfs_list_add_request(req, &mirror->pg_list);
+ mirror->pg_count += req->wb_bytes;
return 1;
}
@@ -888,16 +985,19 @@
*/
static void nfs_pageio_doio(struct nfs_pageio_descriptor *desc)
{
- if (!list_empty(&desc->pg_list)) {
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
+
+ if (!list_empty(&mirror->pg_list)) {
int error = desc->pg_ops->pg_doio(desc);
if (error < 0)
desc->pg_error = error;
else
- desc->pg_bytes_written += desc->pg_count;
+ mirror->pg_bytes_written += mirror->pg_count;
}
- if (list_empty(&desc->pg_list)) {
- desc->pg_count = 0;
- desc->pg_base = 0;
+ if (list_empty(&mirror->pg_list)) {
+ mirror->pg_count = 0;
+ mirror->pg_base = 0;
}
}
@@ -915,10 +1015,14 @@
static int __nfs_pageio_add_request(struct nfs_pageio_descriptor *desc,
struct nfs_page *req)
{
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
struct nfs_page *subreq;
unsigned int bytes_left = 0;
unsigned int offset, pgbase;
+ WARN_ON_ONCE(desc->pg_mirror_idx >= desc->pg_mirror_count);
+
nfs_page_group_lock(req, false);
subreq = req;
@@ -938,7 +1042,7 @@
nfs_pageio_doio(desc);
if (desc->pg_error < 0)
return 0;
- if (desc->pg_recoalesce)
+ if (mirror->pg_recoalesce)
return 0;
/* retry add_request for this subreq */
nfs_page_group_lock(req, false);
@@ -976,14 +1080,16 @@
static int nfs_do_recoalesce(struct nfs_pageio_descriptor *desc)
{
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
LIST_HEAD(head);
do {
- list_splice_init(&desc->pg_list, &head);
- desc->pg_bytes_written -= desc->pg_count;
- desc->pg_count = 0;
- desc->pg_base = 0;
- desc->pg_recoalesce = 0;
+ list_splice_init(&mirror->pg_list, &head);
+ mirror->pg_bytes_written -= mirror->pg_count;
+ mirror->pg_count = 0;
+ mirror->pg_base = 0;
+ mirror->pg_recoalesce = 0;
+
desc->pg_moreio = 0;
while (!list_empty(&head)) {
@@ -997,11 +1103,11 @@
return 0;
break;
}
- } while (desc->pg_recoalesce);
+ } while (mirror->pg_recoalesce);
return 1;
}
-int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc,
+static int nfs_pageio_add_request_mirror(struct nfs_pageio_descriptor *desc,
struct nfs_page *req)
{
int ret;
@@ -1014,9 +1120,78 @@
break;
ret = nfs_do_recoalesce(desc);
} while (ret);
+
return ret;
}
+int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc,
+ struct nfs_page *req)
+{
+ u32 midx;
+ unsigned int pgbase, offset, bytes;
+ struct nfs_page *dupreq, *lastreq;
+
+ pgbase = req->wb_pgbase;
+ offset = req->wb_offset;
+ bytes = req->wb_bytes;
+
+ nfs_pageio_setup_mirroring(desc, req);
+
+ for (midx = 0; midx < desc->pg_mirror_count; midx++) {
+ if (midx) {
+ nfs_page_group_lock(req, false);
+
+ /* find the last request */
+ for (lastreq = req->wb_head;
+ lastreq->wb_this_page != req->wb_head;
+ lastreq = lastreq->wb_this_page)
+ ;
+
+ dupreq = nfs_create_request(req->wb_context,
+ req->wb_page, lastreq, pgbase, bytes);
+
+ if (IS_ERR(dupreq)) {
+ nfs_page_group_unlock(req);
+ return 0;
+ }
+
+ nfs_lock_request(dupreq);
+ nfs_page_group_unlock(req);
+ dupreq->wb_offset = offset;
+ dupreq->wb_index = req->wb_index;
+ } else
+ dupreq = req;
+
+ desc->pg_mirror_idx = midx;
+ if (!nfs_pageio_add_request_mirror(desc, dupreq))
+ return 0;
+ }
+
+ return 1;
+}
+
+/*
+ * nfs_pageio_complete_mirror - Complete I/O on the current mirror of an
+ * nfs_pageio_descriptor
+ * @desc: pointer to io descriptor
+ */
+static void nfs_pageio_complete_mirror(struct nfs_pageio_descriptor *desc,
+ u32 mirror_idx)
+{
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[mirror_idx];
+ u32 restore_idx = desc->pg_mirror_idx;
+
+ desc->pg_mirror_idx = mirror_idx;
+ for (;;) {
+ nfs_pageio_doio(desc);
+ if (!mirror->pg_recoalesce)
+ break;
+ if (!nfs_do_recoalesce(desc))
+ break;
+ }
+ desc->pg_mirror_idx = restore_idx;
+}
+
/*
* nfs_pageio_resend - Transfer requests to new descriptor and resend
* @hdr - the pgio header to move request from
@@ -1055,16 +1230,14 @@
*/
void nfs_pageio_complete(struct nfs_pageio_descriptor *desc)
{
- for (;;) {
- nfs_pageio_doio(desc);
- if (!desc->pg_recoalesce)
- break;
- if (!nfs_do_recoalesce(desc))
- break;
- }
+ u32 midx;
+
+ for (midx = 0; midx < desc->pg_mirror_count; midx++)
+ nfs_pageio_complete_mirror(desc, midx);
if (desc->pg_ops->pg_cleanup)
desc->pg_ops->pg_cleanup(desc);
+ nfs_pageio_cleanup_mirroring(desc);
}
/**
@@ -1080,10 +1253,17 @@
*/
void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *desc, pgoff_t index)
{
- if (!list_empty(&desc->pg_list)) {
- struct nfs_page *prev = nfs_list_entry(desc->pg_list.prev);
- if (index != prev->wb_index + 1)
- nfs_pageio_complete(desc);
+ struct nfs_pgio_mirror *mirror;
+ struct nfs_page *prev;
+ u32 midx;
+
+ for (midx = 0; midx < desc->pg_mirror_count; midx++) {
+ mirror = &desc->pg_mirrors[midx];
+ if (!list_empty(&mirror->pg_list)) {
+ prev = nfs_list_entry(mirror->pg_list.prev);
+ if (index != prev->wb_index + 1)
+ nfs_pageio_complete_mirror(desc, midx);
+ }
}
}
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 2da2e77..5f7c422 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1646,8 +1646,8 @@
* 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)
+pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
+ struct nfs_page *prev, struct nfs_page *req)
{
unsigned int size;
u64 seg_end, req_start, seg_left;
@@ -1729,10 +1729,12 @@
pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
struct nfs_pgio_header *hdr)
{
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
- list_splice_tail_init(&hdr->pages, &desc->pg_list);
+ list_splice_tail_init(&hdr->pages, &mirror->pg_list);
nfs_pageio_reset_write_mds(desc);
- desc->pg_recoalesce = 1;
+ mirror->pg_recoalesce = 1;
}
nfs_pgio_data_destroy(hdr);
}
@@ -1781,12 +1783,14 @@
int
pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
{
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
struct nfs_pgio_header *hdr;
int ret;
hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
if (!hdr) {
- desc->pg_completion_ops->error_cleanup(&desc->pg_list);
+ desc->pg_completion_ops->error_cleanup(&mirror->pg_list);
return -ENOMEM;
}
nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
@@ -1795,6 +1799,7 @@
ret = nfs_generic_pgio(desc, hdr);
if (!ret)
pnfs_do_write(desc, hdr, desc->pg_ioflags);
+
return ret;
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
@@ -1839,10 +1844,13 @@
pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
struct nfs_pgio_header *hdr)
{
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
+
if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
- list_splice_tail_init(&hdr->pages, &desc->pg_list);
+ list_splice_tail_init(&hdr->pages, &mirror->pg_list);
nfs_pageio_reset_read_mds(desc);
- desc->pg_recoalesce = 1;
+ mirror->pg_recoalesce = 1;
}
nfs_pgio_data_destroy(hdr);
}
@@ -1893,12 +1901,14 @@
int
pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
{
+ struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[desc->pg_mirror_idx];
+
struct nfs_pgio_header *hdr;
int ret;
hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
if (!hdr) {
- desc->pg_completion_ops->error_cleanup(&desc->pg_list);
+ desc->pg_completion_ops->error_cleanup(&mirror->pg_list);
return -ENOMEM;
}
nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index 092ab49..568ecf0 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -70,8 +70,15 @@
void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio)
{
+ struct nfs_pgio_mirror *mirror;
+
pgio->pg_ops = &nfs_pgio_rw_ops;
- pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->rsize;
+
+ /* read path should never have more than one mirror */
+ WARN_ON_ONCE(pgio->pg_mirror_count != 1);
+
+ mirror = &pgio->pg_mirrors[0];
+ mirror->pg_bsize = NFS_SERVER(pgio->pg_inode)->rsize;
}
EXPORT_SYMBOL_GPL(nfs_pageio_reset_read_mds);
@@ -81,6 +88,7 @@
struct nfs_page *new;
unsigned int len;
struct nfs_pageio_descriptor pgio;
+ struct nfs_pgio_mirror *pgm;
len = nfs_page_length(page);
if (len == 0)
@@ -97,7 +105,13 @@
&nfs_async_read_completion_ops);
nfs_pageio_add_request(&pgio, new);
nfs_pageio_complete(&pgio);
- NFS_I(inode)->read_io += pgio.pg_bytes_written;
+
+ /* It doesn't make sense to do mirrored reads! */
+ WARN_ON_ONCE(pgio.pg_mirror_count != 1);
+
+ pgm = &pgio.pg_mirrors[0];
+ NFS_I(inode)->read_io += pgm->pg_bytes_written;
+
return 0;
}
@@ -352,6 +366,7 @@
struct list_head *pages, unsigned nr_pages)
{
struct nfs_pageio_descriptor pgio;
+ struct nfs_pgio_mirror *pgm;
struct nfs_readdesc desc = {
.pgio = &pgio,
};
@@ -387,10 +402,15 @@
&nfs_async_read_completion_ops);
ret = read_cache_pages(mapping, pages, readpage_async_filler, &desc);
-
nfs_pageio_complete(&pgio);
- NFS_I(inode)->read_io += pgio.pg_bytes_written;
- npages = (pgio.pg_bytes_written + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+
+ /* It doesn't make sense to do mirrored reads! */
+ WARN_ON_ONCE(pgio.pg_mirror_count != 1);
+
+ pgm = &pgio.pg_mirrors[0];
+ NFS_I(inode)->read_io += pgm->pg_bytes_written;
+ npages = (pgm->pg_bytes_written + PAGE_CACHE_SIZE - 1) >>
+ PAGE_CACHE_SHIFT;
nfs_add_stats(inode, NFSIOS_READPAGES, npages);
read_complete:
put_nfs_open_context(desc.ctx);
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 2bee165..ceacfee 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -906,7 +906,7 @@
if (nfs_write_need_commit(hdr)) {
memcpy(&req->wb_verf, &hdr->verf.verifier, sizeof(req->wb_verf));
nfs_mark_request_commit(req, hdr->lseg, &cinfo,
- 0);
+ hdr->pgio_mirror_idx);
goto next;
}
remove_req:
@@ -1304,8 +1304,14 @@
void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio)
{
+ struct nfs_pgio_mirror *mirror;
+
pgio->pg_ops = &nfs_pgio_rw_ops;
- pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->wsize;
+
+ nfs_pageio_stop_mirroring(pgio);
+
+ mirror = &pgio->pg_mirrors[0];
+ mirror->pg_bsize = NFS_SERVER(pgio->pg_inode)->wsize;
}
EXPORT_SYMBOL_GPL(nfs_pageio_reset_write_mds);
diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h
index 479c566..3eb072d 100644
--- a/include/linux/nfs_page.h
+++ b/include/linux/nfs_page.h
@@ -58,6 +58,8 @@
size_t (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *,
struct nfs_page *);
int (*pg_doio)(struct nfs_pageio_descriptor *);
+ unsigned int (*pg_get_mirror_count)(struct nfs_pageio_descriptor *,
+ struct nfs_page *);
void (*pg_cleanup)(struct nfs_pageio_descriptor *);
};
@@ -74,15 +76,17 @@
struct rpc_task_setup *, int);
};
-struct nfs_pageio_descriptor {
+struct nfs_pgio_mirror {
struct list_head pg_list;
unsigned long pg_bytes_written;
size_t pg_count;
size_t pg_bsize;
unsigned int pg_base;
- unsigned char pg_moreio : 1,
- pg_recoalesce : 1;
+ unsigned char pg_recoalesce : 1;
+};
+struct nfs_pageio_descriptor {
+ unsigned char pg_moreio : 1;
struct inode *pg_inode;
const struct nfs_pageio_ops *pg_ops;
const struct nfs_rw_ops *pg_rw_ops;
@@ -93,8 +97,18 @@
struct pnfs_layout_segment *pg_lseg;
struct nfs_direct_req *pg_dreq;
void *pg_layout_private;
+ unsigned int pg_bsize; /* default bsize for mirrors */
+
+ u32 pg_mirror_count;
+ struct nfs_pgio_mirror *pg_mirrors;
+ struct nfs_pgio_mirror pg_mirrors_static[1];
+ struct nfs_pgio_mirror *pg_mirrors_dynamic;
+ u32 pg_mirror_idx; /* current mirror */
};
+/* arbitrarily selected limit to number of mirrors */
+#define NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX 16
+
#define NFS_WBACK_BUSY(req) (test_bit(PG_BUSY,&(req)->wb_flags))
extern struct nfs_page *nfs_create_request(struct nfs_open_context *ctx,
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 5bc99f0..6400a1e0 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1329,6 +1329,7 @@
struct nfs_page_array page_array;
struct nfs_client *ds_clp; /* pNFS data server */
int ds_commit_idx; /* ds index if ds_clp is set */
+ int pgio_mirror_idx;/* mirror index in pgio layer */
};
struct nfs_mds_commit_info {
