[PATCH net-next 07/10] net/smc: introduce sg-logic for send buffers

Ursula Braun
2017-07-28T11:56:19Z

SMC send buffers are processed the same way as RMBs. Since RMBs have
been converted to sg-logic, do the same for send buffers.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
---
net/smc/smc_core.c | 46 +++++++++++++++++++++++++++++++++++-----------
net/smc/smc_core.h | 2 --
net/smc/smc_ib.c | 29 -----------------------------
net/smc/smc_ib.h | 6 ------
net/smc/smc_tx.c | 6 +++---
5 files changed, 38 insertions(+), 51 deletions(-)

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 87bb3e4771a8..8795c7ed9ce4 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -248,6 +248,7 @@ static void smc_link_clear(struct smc_link *lnk)

static void smc_lgr_free_sndbufs(struct smc_link_group *lgr)
{
+ struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
struct smc_buf_desc *sndbuf_desc, *bf_desc;
int i;

@@ -255,10 +256,11 @@ static void smc_lgr_free_sndbufs(struct smc_link_group *lgr)
list_for_each_entry_safe(sndbuf_desc, bf_desc, &lgr->sndbufs[i],
list) {
list_del(&sndbuf_desc->list);
- smc_ib_buf_unmap(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
- smc_uncompress_bufsize(i),
- sndbuf_desc, DMA_TO_DEVICE);
- kfree(sndbuf_desc->cpu_addr);
+ smc_ib_buf_unmap_sg(lnk->smcibdev, sndbuf_desc,
+ DMA_TO_DEVICE);
+ sg_free_table(&sndbuf_desc->sgt[SMC_SINGLE_LINK]);
+ free_pages((unsigned long)sndbuf_desc->cpu_addr,
+ sndbuf_desc->order);
kfree(sndbuf_desc);
}
}
@@ -517,6 +519,9 @@ int smc_sndbuf_create(struct smc_sock *smc)
for (bufsize_short = smc_compress_bufsize(smc->sk.sk_sndbuf / 2);
bufsize_short >= 0; bufsize_short--) {
bufsize = smc_uncompress_bufsize(bufsize_short);
+ if ((1 << get_order(bufsize)) > SG_MAX_SINGLE_ALLOC)
+ continue;
+
/* check for reusable sndbuf_slot in the link group */
sndbuf_desc = smc_sndbuf_get_slot(lgr, bufsize_short);
if (sndbuf_desc) {
@@ -527,10 +532,12 @@ int smc_sndbuf_create(struct smc_sock *smc)
sndbuf_desc = kzalloc(sizeof(*sndbuf_desc), GFP_KERNEL);
if (!sndbuf_desc)
break; /* give up with -ENOMEM */
- sndbuf_desc->cpu_addr = kzalloc(bufsize,
- GFP_KERNEL | __GFP_NOWARN |
- __GFP_NOMEMALLOC |
- __GFP_NORETRY);
+
+ sndbuf_desc->cpu_addr =
+ (void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN |
+ __GFP_NOMEMALLOC |
+ __GFP_NORETRY | __GFP_ZERO,
+ get_order(bufsize));
if (!sndbuf_desc->cpu_addr) {
kfree(sndbuf_desc);
sndbuf_desc = NULL;
@@ -539,14 +546,31 @@ int smc_sndbuf_create(struct smc_sock *smc)
*/
continue;
}
- rc = smc_ib_buf_map(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
- bufsize, sndbuf_desc, DMA_TO_DEVICE);
+ sndbuf_desc->order = get_order(bufsize);
+
+ rc = sg_alloc_table(&sndbuf_desc->sgt[SMC_SINGLE_LINK], 1,
+ GFP_KERNEL);
if (rc) {
- kfree(sndbuf_desc->cpu_addr);
+ free_pages((unsigned long)sndbuf_desc->cpu_addr,
+ sndbuf_desc->order);
+ kfree(sndbuf_desc);
+ sndbuf_desc = NULL;
+ continue;
+ }
+ sg_set_buf(sndbuf_desc->sgt[SMC_SINGLE_LINK].sgl,
+ sndbuf_desc->cpu_addr, bufsize);
+
+ rc = smc_ib_buf_map_sg(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
+ sndbuf_desc, DMA_TO_DEVICE);
+ if (rc != 1) {
+ sg_free_table(&sndbuf_desc->sgt[SMC_SINGLE_LINK]);
+ free_pages((unsigned long)sndbuf_desc->cpu_addr,
+ sndbuf_desc->order);
kfree(sndbuf_desc);
sndbuf_desc = NULL;
continue; /* if mapping failed, try smaller one */
}
+
sndbuf_desc->used = 1;
write_lock_bh(&lgr->sndbufs_lock);
list_add(&sndbuf_desc->list, &lgr->sndbufs[bufsize_short]);
diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index f7b40bdbf24c..72c25cb3eb89 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -102,8 +102,6 @@ struct smc_link {
/* tx/rx buffer list element for sndbufs list and rmbs list of a lgr */
struct smc_buf_desc {
struct list_head list;
- u64 dma_addr[SMC_LINKS_PER_LGR_MAX];
- /* mapped address of buffer */
void *cpu_addr; /* virtual address of buffer */
struct sg_table sgt[SMC_LINKS_PER_LGR_MAX];/* virtual buffer */
struct ib_mr *mr_rx[SMC_LINKS_PER_LGR_MAX];
diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c
index 85e1831f591e..021f061609f5 100644
--- a/net/smc/smc_ib.c
+++ b/net/smc/smc_ib.c
@@ -295,35 +295,6 @@ int smc_ib_get_memory_region(struct ib_pd *pd, int access_flags,
return 0;
}

-/* map a new TX or RX buffer to DMA */
-int smc_ib_buf_map(struct smc_ib_device *smcibdev, int buf_size,
- struct smc_buf_desc *buf_slot,
- enum dma_data_direction data_direction)
-{
- int rc = 0;
-
- if (buf_slot->dma_addr[SMC_SINGLE_LINK])
- return rc; /* already mapped */
- buf_slot->dma_addr[SMC_SINGLE_LINK] =
- ib_dma_map_single(smcibdev->ibdev, buf_slot->cpu_addr,
- buf_size, data_direction);
- if (ib_dma_mapping_error(smcibdev->ibdev,
- buf_slot->dma_addr[SMC_SINGLE_LINK]))
- rc = -EIO;
- return rc;
-}
-
-void smc_ib_buf_unmap(struct smc_ib_device *smcibdev, int buf_size,
- struct smc_buf_desc *buf_slot,
- enum dma_data_direction data_direction)
-{
- if (!buf_slot->dma_addr[SMC_SINGLE_LINK])
- return; /* already unmapped */
- ib_dma_unmap_single(smcibdev->ibdev, *buf_slot->dma_addr, buf_size,
- data_direction);
- buf_slot->dma_addr[SMC_SINGLE_LINK] = 0;
-}
-
/* Map a new TX or RX buffer SG-table to DMA */
int smc_ib_buf_map_sg(struct smc_ib_device *smcibdev,
struct smc_buf_desc *buf_slot,
diff --git a/net/smc/smc_ib.h b/net/smc/smc_ib.h
index b57d29f29042..72acb19ffc67 100644
--- a/net/smc/smc_ib.h
+++ b/net/smc/smc_ib.h
@@ -51,12 +51,6 @@ int smc_ib_register_client(void) __init;
void smc_ib_unregister_client(void);
bool smc_ib_port_active(struct smc_ib_device *smcibdev, u8 ibport);
int smc_ib_remember_port_attr(struct smc_ib_device *smcibdev, u8 ibport);
-int smc_ib_buf_map(struct smc_ib_device *smcibdev, int buf_size,
- struct smc_buf_desc *buf_slot,
- enum dma_data_direction data_direction);
-void smc_ib_buf_unmap(struct smc_ib_device *smcibdev, int bufsize,
- struct smc_buf_desc *buf_slot,
- enum dma_data_direction data_direction);
int smc_ib_buf_map_sg(struct smc_ib_device *smcibdev,
struct smc_buf_desc *buf_slot,
enum dma_data_direction data_direction);
diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c
index 21ec1832ab51..f4d58e2dd559 100644
--- a/net/smc/smc_tx.c
+++ b/net/smc/smc_tx.c
@@ -277,6 +277,7 @@ static int smc_tx_rdma_writes(struct smc_connection *conn)
struct smc_link_group *lgr = conn->lgr;
int to_send, rmbespace;
struct smc_link *link;
+ dma_addr_t dma_addr;
int num_sges;
int rc;

@@ -334,12 +335,11 @@ static int smc_tx_rdma_writes(struct smc_connection *conn)
src_len = conn->sndbuf_size - sent.count;
}
src_len_sum = src_len;
+ dma_addr = sg_dma_address(conn->sndbuf_desc->sgt[SMC_SINGLE_LINK].sgl);
for (dstchunk = 0; dstchunk < 2; dstchunk++) {
num_sges = 0;
for (srcchunk = 0; srcchunk < 2; srcchunk++) {
- sges[srcchunk].addr =
- conn->sndbuf_desc->dma_addr[SMC_SINGLE_LINK] +
- src_off;
+ sges[srcchunk].addr = dma_addr + src_off;
sges[srcchunk].length = src_len;
sges[srcchunk].lkey = link->roce_pd->local_dma_lkey;
num_sges++;
--
2.11.2