[RFC PATCH 07/09] Support page offset in memory regsitrations

From: Long Li
Date: Thu May 17 2018 - 19:27:07 EST


From: Long Li <longli@xxxxxxxxxxxxx>

Now momory registration needs to recognize offset in page when direct transfer is
used.

Signed-off-by: Long Li <longli@xxxxxxxxxxxxx>
---
fs/cifs/smb2pdu.c | 19 +++++++++-----
fs/cifs/smbdirect.c | 74 +++++++++++++++++++++++++++++++----------------------
fs/cifs/smbdirect.h | 2 +-
3 files changed, 57 insertions(+), 38 deletions(-)

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index fdcf97e..a23c7cb 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -2586,6 +2586,8 @@ smb2_new_read_req(void **buf, unsigned int *total_len,
req->MinimumCount = 0;
req->Length = cpu_to_le32(io_parms->length);
req->Offset = cpu_to_le64(io_parms->offset);
+ if (!rdata->tailsz)
+ rdata->tailsz = rdata->pagesz;
#ifdef CONFIG_CIFS_SMB_DIRECT
/*
* If we want to do a RDMA write, fill in and append
@@ -2601,8 +2603,8 @@ smb2_new_read_req(void **buf, unsigned int *total_len,
rcu_read_lock();
rcu_dereference(server->smbd_conn);
rdata->mr = smbd_register_mr(
- server->smbd_conn, rdata->pages,
- rdata->nr_pages, rdata->tailsz,
+ server->smbd_conn, rdata->direct_pages ? rdata->direct_pages : rdata->pages,
+ rdata->nr_pages, rdata->page_offset, rdata->tailsz,
true, need_invalidate);
rcu_read_unlock();
if (!rdata->mr)
@@ -2967,6 +2969,8 @@ smb2_async_writev(struct cifs_writedata *wdata,
req->DataOffset = cpu_to_le16(
offsetof(struct smb2_write_req, Buffer));
req->RemainingBytes = 0;
+ if (!wdata->tailsz)
+ wdata->tailsz = wdata->pagesz;
#ifdef CONFIG_CIFS_SMB_DIRECT
/*
* If we want to do a server RDMA read, fill in and append
@@ -2981,8 +2985,8 @@ smb2_async_writev(struct cifs_writedata *wdata,
rcu_read_lock();
rcu_dereference(server->smbd_conn);
wdata->mr = smbd_register_mr(
- server->smbd_conn, wdata->pages,
- wdata->nr_pages, wdata->tailsz,
+ server->smbd_conn, wdata->direct_pages ? wdata->direct_pages : wdata->pages,
+ wdata->nr_pages, wdata->page_offset, wdata->tailsz,
false, need_invalidate);
rcu_read_unlock();
if (!wdata->mr) {
@@ -2991,8 +2995,11 @@ smb2_async_writev(struct cifs_writedata *wdata,
}
req->Length = 0;
req->DataOffset = 0;
- req->RemainingBytes =
- cpu_to_le32((wdata->nr_pages-1)*PAGE_SIZE + wdata->tailsz);
+ if (wdata->nr_pages > 1)
+ req->RemainingBytes =
+ cpu_to_le32((wdata->nr_pages-1)*PAGE_SIZE - wdata->page_offset + wdata->tailsz);
+ else
+ req->RemainingBytes = cpu_to_le32(wdata->tailsz);
req->Channel = SMB2_CHANNEL_RDMA_V1_INVALIDATE;
if (need_invalidate)
req->Channel = SMB2_CHANNEL_RDMA_V1;
diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c
index 939c289..bce1e7a 100644
--- a/fs/cifs/smbdirect.c
+++ b/fs/cifs/smbdirect.c
@@ -2267,37 +2267,37 @@ static void smbd_mr_recovery_work(struct work_struct *work)
if (smbdirect_mr->state == MR_INVALIDATED ||
smbdirect_mr->state == MR_ERROR) {

- if (smbdirect_mr->state == MR_INVALIDATED) {
+ /* recover this MR entry */
+ rc = ib_dereg_mr(smbdirect_mr->mr);
+ if (rc) {
+ log_rdma_mr(ERR,
+ "ib_dereg_mr failed rc=%x\n",
+ rc);
+ smbd_disconnect_rdma_connection(info);
+ continue;
+ }
+
+ smbdirect_mr->mr = ib_alloc_mr(
+ info->pd, info->mr_type,
+ info->max_frmr_depth);
+ if (IS_ERR(smbdirect_mr->mr)) {
+ log_rdma_mr(ERR,
+ "ib_alloc_mr failed mr_type=%x "
+ "max_frmr_depth=%x\n",
+ info->mr_type,
+ info->max_frmr_depth);
+ smbd_disconnect_rdma_connection(info);
+ continue;
+ }
+
+ if (smbdirect_mr->state == MR_INVALIDATED)
ib_dma_unmap_sg(
info->id->device, smbdirect_mr->sgl,
smbdirect_mr->sgl_count,
smbdirect_mr->dir);
- smbdirect_mr->state = MR_READY;
- } else if (smbdirect_mr->state == MR_ERROR) {
-
- /* recover this MR entry */
- rc = ib_dereg_mr(smbdirect_mr->mr);
- if (rc) {
- log_rdma_mr(ERR,
- "ib_dereg_mr failed rc=%x\n",
- rc);
- smbd_disconnect_rdma_connection(info);
- }

- smbdirect_mr->mr = ib_alloc_mr(
- info->pd, info->mr_type,
- info->max_frmr_depth);
- if (IS_ERR(smbdirect_mr->mr)) {
- log_rdma_mr(ERR,
- "ib_alloc_mr failed mr_type=%x "
- "max_frmr_depth=%x\n",
- info->mr_type,
- info->max_frmr_depth);
- smbd_disconnect_rdma_connection(info);
- }
+ smbdirect_mr->state = MR_READY;

- smbdirect_mr->state = MR_READY;
- }
/* smbdirect_mr->state is updated by this function
* and is read and updated by I/O issuing CPUs trying
* to get a MR, the call to atomic_inc_return
@@ -2443,7 +2443,7 @@ static struct smbd_mr *get_mr(struct smbd_connection *info)
*/
struct smbd_mr *smbd_register_mr(
struct smbd_connection *info, struct page *pages[], int num_pages,
- int tailsz, bool writing, bool need_invalidate)
+ int offset, int tailsz, bool writing, bool need_invalidate)
{
struct smbd_mr *smbdirect_mr;
int rc, i;
@@ -2466,17 +2466,29 @@ struct smbd_mr *smbd_register_mr(
smbdirect_mr->sgl_count = num_pages;
sg_init_table(smbdirect_mr->sgl, num_pages);

- for (i = 0; i < num_pages - 1; i++)
- sg_set_page(&smbdirect_mr->sgl[i], pages[i], PAGE_SIZE, 0);
+ log_rdma_mr(INFO, "num_pages=0x%x offset=0x%x tailsz=0x%x\n", num_pages, offset, tailsz);

+ if (num_pages==1) {
+ sg_set_page(&smbdirect_mr->sgl[0], pages[0], tailsz, offset);
+ goto next;
+ }
+
+ /* We have at least two pages to register */
+ sg_set_page(&smbdirect_mr->sgl[0], pages[0], PAGE_SIZE - offset, offset);
+ i = 1;
+ while (i < num_pages - 1) {
+ sg_set_page(&smbdirect_mr->sgl[i], pages[i], PAGE_SIZE, 0);
+ i++;
+ }
sg_set_page(&smbdirect_mr->sgl[i], pages[i],
tailsz ? tailsz : PAGE_SIZE, 0);

+next:
dir = writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
smbdirect_mr->dir = dir;
rc = ib_dma_map_sg(info->id->device, smbdirect_mr->sgl, num_pages, dir);
if (!rc) {
- log_rdma_mr(INFO, "ib_dma_map_sg num_pages=%x dir=%x rc=%x\n",
+ log_rdma_mr(ERR, "ib_dma_map_sg num_pages=%x dir=%x rc=%x\n",
num_pages, dir, rc);
goto dma_map_error;
}
@@ -2484,8 +2496,8 @@ struct smbd_mr *smbd_register_mr(
rc = ib_map_mr_sg(smbdirect_mr->mr, smbdirect_mr->sgl, num_pages,
NULL, PAGE_SIZE);
if (rc != num_pages) {
- log_rdma_mr(INFO,
- "ib_map_mr_sg failed rc = %x num_pages = %x\n",
+ log_rdma_mr(ERR,
+ "ib_map_mr_sg failed rc = %d num_pages = %x\n",
rc, num_pages);
goto map_mr_error;
}
diff --git a/fs/cifs/smbdirect.h b/fs/cifs/smbdirect.h
index f568577..bb1e0c4 100644
--- a/fs/cifs/smbdirect.h
+++ b/fs/cifs/smbdirect.h
@@ -314,7 +314,7 @@ struct smbd_mr {
/* Interfaces to register and deregister MR for RDMA read/write */
struct smbd_mr *smbd_register_mr(
struct smbd_connection *info, struct page *pages[], int num_pages,
- int tailsz, bool writing, bool need_invalidate);
+ int offset, int tailsz, bool writing, bool need_invalidate);
int smbd_deregister_mr(struct smbd_mr *mr);

#else
--
2.7.4