[PATCH v2 069/127] smb: client: make use of smbdirect_map_sges_from_iter()
Stefan Metzmacher
metze at samba.org
Wed Oct 29 13:20:47 UTC 2025
This is basically a copy of smb_extract_iter_to_rdma() moved
to common code.
Before we had the inconsistency we called ib_dma_unmap_single(),
while we mapped using ib_dma_map_page() in smb_set_sge().
Now ib_dma_unmap_page() is used for consistency.
It doesn't really matter as ib_dma_unmap_single() and
ib_dma_unmap_page() both operate
on dma_addr_t and dma_unmap_single_attrs() is just an
alias for dma_unmap_page_attrs().
Cc: Steve French <smfrench at gmail.com>
Cc: Tom Talpey <tom at talpey.com>
Cc: Long Li <longli at microsoft.com>
Cc: Namjae Jeon <linkinjeon at kernel.org>
Cc: linux-cifs at vger.kernel.org
Cc: samba-technical at lists.samba.org
Signed-off-by: Stefan Metzmacher <metze at samba.org>
Signed-off-by: Steve French <stfrench at microsoft.com>
---
fs/smb/client/smbdirect.c | 241 +-------------------------------------
1 file changed, 5 insertions(+), 236 deletions(-)
diff --git a/fs/smb/client/smbdirect.c b/fs/smb/client/smbdirect.c
index 689b691557c2..19971f7c4670 100644
--- a/fs/smb/client/smbdirect.c
+++ b/fs/smb/client/smbdirect.c
@@ -32,17 +32,6 @@ static int smbd_post_send_empty(struct smbdirect_socket *sc);
static void destroy_mr_list(struct smbdirect_socket *sc);
static int allocate_mr_list(struct smbdirect_socket *sc);
-struct smb_extract_to_rdma {
- struct ib_sge *sge;
- unsigned int nr_sge;
- unsigned int max_sge;
- struct ib_device *device;
- u32 local_dma_lkey;
- enum dma_data_direction direction;
-};
-static ssize_t smb_extract_iter_to_rdma(struct iov_iter *iter, size_t len,
- struct smb_extract_to_rdma *rdma);
-
/* Port numbers for SMBD transport */
#define SMB_PORT 445
#define SMBD_PORT 5445
@@ -1025,9 +1014,9 @@ static int smbd_post_send_iter(struct smbdirect_socket *sc,
/* Fill in the data payload to find out how much data we can add */
if (iter) {
- struct smb_extract_to_rdma extract = {
- .nr_sge = request->num_sge,
- .max_sge = SMBDIRECT_SEND_IO_MAX_SGE,
+ struct smbdirect_map_sges extract = {
+ .num_sge = request->num_sge,
+ .max_sge = ARRAY_SIZE(request->sge),
.sge = request->sge,
.device = sc->ib.dev,
.local_dma_lkey = sc->ib.pd->local_dma_lkey,
@@ -1036,12 +1025,11 @@ static int smbd_post_send_iter(struct smbdirect_socket *sc,
size_t payload_len = umin(*_remaining_data_length,
sp->max_send_size - sizeof(*packet));
- rc = smb_extract_iter_to_rdma(iter, payload_len,
- &extract);
+ rc = smbdirect_map_sges_from_iter(iter, payload_len, &extract);
if (rc < 0)
goto err_dma;
data_length = rc;
- request->num_sge = extract.nr_sge;
+ request->num_sge = extract.num_sge;
*_remaining_data_length -= data_length;
} else {
data_length = 0;
@@ -2397,222 +2385,3 @@ void smbd_deregister_mr(struct smbdirect_mr_io *mr)
if (!kref_put(&mr->kref, smbd_mr_free_locked))
mutex_unlock(&mr->mutex);
}
-
-static bool smb_set_sge(struct smb_extract_to_rdma *rdma,
- struct page *lowest_page, size_t off, size_t len)
-{
- struct ib_sge *sge = &rdma->sge[rdma->nr_sge];
- u64 addr;
-
- addr = ib_dma_map_page(rdma->device, lowest_page,
- off, len, rdma->direction);
- if (ib_dma_mapping_error(rdma->device, addr))
- return false;
-
- sge->addr = addr;
- sge->length = len;
- sge->lkey = rdma->local_dma_lkey;
- rdma->nr_sge++;
- return true;
-}
-
-/*
- * Extract page fragments from a BVEC-class iterator and add them to an RDMA
- * element list. The pages are not pinned.
- */
-static ssize_t smb_extract_bvec_to_rdma(struct iov_iter *iter,
- struct smb_extract_to_rdma *rdma,
- ssize_t maxsize)
-{
- const struct bio_vec *bv = iter->bvec;
- unsigned long start = iter->iov_offset;
- unsigned int i;
- ssize_t ret = 0;
-
- for (i = 0; i < iter->nr_segs; i++) {
- size_t off, len;
-
- len = bv[i].bv_len;
- if (start >= len) {
- start -= len;
- continue;
- }
-
- len = min_t(size_t, maxsize, len - start);
- off = bv[i].bv_offset + start;
-
- if (!smb_set_sge(rdma, bv[i].bv_page, off, len))
- return -EIO;
-
- ret += len;
- maxsize -= len;
- if (rdma->nr_sge >= rdma->max_sge || maxsize <= 0)
- break;
- start = 0;
- }
-
- if (ret > 0)
- iov_iter_advance(iter, ret);
- return ret;
-}
-
-/*
- * Extract fragments from a KVEC-class iterator and add them to an RDMA list.
- * This can deal with vmalloc'd buffers as well as kmalloc'd or static buffers.
- * The pages are not pinned.
- */
-static ssize_t smb_extract_kvec_to_rdma(struct iov_iter *iter,
- struct smb_extract_to_rdma *rdma,
- ssize_t maxsize)
-{
- const struct kvec *kv = iter->kvec;
- unsigned long start = iter->iov_offset;
- unsigned int i;
- ssize_t ret = 0;
-
- for (i = 0; i < iter->nr_segs; i++) {
- struct page *page;
- unsigned long kaddr;
- size_t off, len, seg;
-
- len = kv[i].iov_len;
- if (start >= len) {
- start -= len;
- continue;
- }
-
- kaddr = (unsigned long)kv[i].iov_base + start;
- off = kaddr & ~PAGE_MASK;
- len = min_t(size_t, maxsize, len - start);
- kaddr &= PAGE_MASK;
-
- maxsize -= len;
- do {
- seg = min_t(size_t, len, PAGE_SIZE - off);
-
- if (is_vmalloc_or_module_addr((void *)kaddr))
- page = vmalloc_to_page((void *)kaddr);
- else
- page = virt_to_page((void *)kaddr);
-
- if (!smb_set_sge(rdma, page, off, seg))
- return -EIO;
-
- ret += seg;
- len -= seg;
- kaddr += PAGE_SIZE;
- off = 0;
- } while (len > 0 && rdma->nr_sge < rdma->max_sge);
-
- if (rdma->nr_sge >= rdma->max_sge || maxsize <= 0)
- break;
- start = 0;
- }
-
- if (ret > 0)
- iov_iter_advance(iter, ret);
- return ret;
-}
-
-/*
- * Extract folio fragments from a FOLIOQ-class iterator and add them to an RDMA
- * list. The folios are not pinned.
- */
-static ssize_t smb_extract_folioq_to_rdma(struct iov_iter *iter,
- struct smb_extract_to_rdma *rdma,
- ssize_t maxsize)
-{
- const struct folio_queue *folioq = iter->folioq;
- unsigned int slot = iter->folioq_slot;
- ssize_t ret = 0;
- size_t offset = iter->iov_offset;
-
- BUG_ON(!folioq);
-
- if (slot >= folioq_nr_slots(folioq)) {
- folioq = folioq->next;
- if (WARN_ON_ONCE(!folioq))
- return -EIO;
- slot = 0;
- }
-
- do {
- struct folio *folio = folioq_folio(folioq, slot);
- size_t fsize = folioq_folio_size(folioq, slot);
-
- if (offset < fsize) {
- size_t part = umin(maxsize, fsize - offset);
-
- if (!smb_set_sge(rdma, folio_page(folio, 0), offset, part))
- return -EIO;
-
- offset += part;
- ret += part;
- maxsize -= part;
- }
-
- if (offset >= fsize) {
- offset = 0;
- slot++;
- if (slot >= folioq_nr_slots(folioq)) {
- if (!folioq->next) {
- WARN_ON_ONCE(ret < iter->count);
- break;
- }
- folioq = folioq->next;
- slot = 0;
- }
- }
- } while (rdma->nr_sge < rdma->max_sge && maxsize > 0);
-
- iter->folioq = folioq;
- iter->folioq_slot = slot;
- iter->iov_offset = offset;
- iter->count -= ret;
- return ret;
-}
-
-/*
- * Extract page fragments from up to the given amount of the source iterator
- * and build up an RDMA list that refers to all of those bits. The RDMA list
- * is appended to, up to the maximum number of elements set in the parameter
- * block.
- *
- * The extracted page fragments are not pinned or ref'd in any way; if an
- * IOVEC/UBUF-type iterator is to be used, it should be converted to a
- * BVEC-type iterator and the pages pinned, ref'd or otherwise held in some
- * way.
- */
-static ssize_t smb_extract_iter_to_rdma(struct iov_iter *iter, size_t len,
- struct smb_extract_to_rdma *rdma)
-{
- ssize_t ret;
- int before = rdma->nr_sge;
-
- switch (iov_iter_type(iter)) {
- case ITER_BVEC:
- ret = smb_extract_bvec_to_rdma(iter, rdma, len);
- break;
- case ITER_KVEC:
- ret = smb_extract_kvec_to_rdma(iter, rdma, len);
- break;
- case ITER_FOLIOQ:
- ret = smb_extract_folioq_to_rdma(iter, rdma, len);
- break;
- default:
- WARN_ON_ONCE(1);
- return -EIO;
- }
-
- if (ret < 0) {
- while (rdma->nr_sge > before) {
- struct ib_sge *sge = &rdma->sge[rdma->nr_sge--];
-
- ib_dma_unmap_single(rdma->device, sge->addr, sge->length,
- rdma->direction);
- sge->addr = 0;
- }
- }
-
- return ret;
-}
--
2.43.0
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