net/smc: cleanup function __smc_buf_create()

Split function __smc_buf_create() for better readability.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ursula Braun 2017-07-28 13:56:21 +02:00 committed by David S. Miller
parent 3e034725c0
commit b33982c3a6

View File

@ -487,6 +487,64 @@ static inline int smc_rmb_wnd_update_limit(int rmbe_size)
return min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
}
static struct smc_buf_desc *smc_new_buf_create(struct smc_link_group *lgr,
bool is_rmb, int bufsize)
{
struct smc_buf_desc *buf_desc;
struct smc_link *lnk;
int rc;
/* try to alloc a new buffer */
buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
if (!buf_desc)
return ERR_PTR(-ENOMEM);
buf_desc->cpu_addr =
(void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN |
__GFP_NOMEMALLOC |
__GFP_NORETRY | __GFP_ZERO,
get_order(bufsize));
if (!buf_desc->cpu_addr) {
kfree(buf_desc);
return ERR_PTR(-EAGAIN);
}
buf_desc->order = get_order(bufsize);
/* build the sg table from the pages */
lnk = &lgr->lnk[SMC_SINGLE_LINK];
rc = sg_alloc_table(&buf_desc->sgt[SMC_SINGLE_LINK], 1,
GFP_KERNEL);
if (rc) {
smc_buf_free(buf_desc, lnk, is_rmb);
return ERR_PTR(rc);
}
sg_set_buf(buf_desc->sgt[SMC_SINGLE_LINK].sgl,
buf_desc->cpu_addr, bufsize);
/* map sg table to DMA address */
rc = smc_ib_buf_map_sg(lnk->smcibdev, buf_desc,
is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
/* SMC protocol depends on mapping to one DMA address only */
if (rc != 1) {
smc_buf_free(buf_desc, lnk, is_rmb);
return ERR_PTR(-EAGAIN);
}
/* create a new memory region for the RMB */
if (is_rmb) {
rc = smc_ib_get_memory_region(lnk->roce_pd,
IB_ACCESS_REMOTE_WRITE |
IB_ACCESS_LOCAL_WRITE,
buf_desc);
if (rc) {
smc_buf_free(buf_desc, lnk, is_rmb);
return ERR_PTR(rc);
}
}
return buf_desc;
}
static int __smc_buf_create(struct smc_sock *smc, bool is_rmb)
{
struct smc_connection *conn = &smc->conn;
@ -494,12 +552,9 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_rmb)
struct smc_buf_desc *buf_desc = NULL;
struct list_head *buf_list;
int bufsize, bufsize_short;
struct smc_link *lnk;
int sk_buf_size;
rwlock_t *lock;
int rc;
lnk = &lgr->lnk[SMC_SINGLE_LINK];
if (is_rmb)
/* use socket recv buffer size (w/o overhead) as start value */
sk_buf_size = smc->sk.sk_rcvbuf / 2;
@ -528,54 +583,11 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_rmb)
break; /* found reusable slot */
}
/* try to allocate the determined number of pages */
buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
if (!buf_desc)
break; /* give up with -ENOMEM */
buf_desc->cpu_addr =
(void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN |
__GFP_NOMEMALLOC |
__GFP_NORETRY | __GFP_ZERO,
get_order(bufsize));
if (!buf_desc->cpu_addr) {
kfree(buf_desc);
buf_desc = NULL;
buf_desc = smc_new_buf_create(lgr, is_rmb, bufsize);
if (PTR_ERR(buf_desc) == -ENOMEM)
break;
if (IS_ERR(buf_desc))
continue;
}
rc = sg_alloc_table(&buf_desc->sgt[SMC_SINGLE_LINK], 1,
GFP_KERNEL);
if (rc) {
smc_buf_free(buf_desc, lnk, is_rmb);
buf_desc = NULL;
continue;
}
sg_set_buf(buf_desc->sgt[SMC_SINGLE_LINK].sgl,
buf_desc->cpu_addr, bufsize);
/* map sg table to DMA address */
rc = smc_ib_buf_map_sg(lnk->smcibdev, buf_desc, is_rmb ?
DMA_FROM_DEVICE : DMA_TO_DEVICE);
/* SMC protocol depends on mapping to one DMA address only */
if (rc != 1) {
smc_buf_free(buf_desc, lnk, is_rmb);
buf_desc = NULL;
continue; /* if mapping failed, try smaller one */
}
/* create a new memory region for the RMB */
if (is_rmb) {
rc = smc_ib_get_memory_region(lnk->roce_pd,
IB_ACCESS_REMOTE_WRITE |
IB_ACCESS_LOCAL_WRITE,
buf_desc);
if (rc) {
smc_buf_free(buf_desc, lnk, is_rmb);
buf_desc = NULL;
continue;
}
}
buf_desc->used = 1;
write_lock_bh(lock);
@ -584,7 +596,7 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_rmb)
break; /* found */
}
if (!buf_desc || !buf_desc->cpu_addr)
if (IS_ERR(buf_desc))
return -ENOMEM;
if (is_rmb) {