Make smb_extract_iter_to_rdma() extract page fragments from an ITER_FOLIOQ iterator into RDMA SGEs. Signed-off-by: David Howells <dhowells@xxxxxxxxxx> cc: Steve French <sfrench@xxxxxxxxx> cc: Paulo Alcantara <pc@xxxxxxxxxxxxx> cc: Tom Talpey <tom@xxxxxxxxxx> cc: Enzo Matsumiya <ematsumiya@xxxxxxx> cc: linux-cifs@xxxxxxxxxxxxxxx --- fs/smb/client/smbdirect.c | 71 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 68 insertions(+), 3 deletions(-) diff --git a/fs/smb/client/smbdirect.c b/fs/smb/client/smbdirect.c index 7bcc379014ca..c946b38ca825 100644 --- a/fs/smb/client/smbdirect.c +++ b/fs/smb/client/smbdirect.c @@ -6,6 +6,7 @@ */ #include <linux/module.h> #include <linux/highmem.h> +#include <linux/folio_queue.h> #include "smbdirect.h" #include "cifs_debug.h" #include "cifsproto.h" @@ -2463,6 +2464,8 @@ static ssize_t smb_extract_bvec_to_rdma(struct iov_iter *iter, start = 0; } + if (ret > 0) + iov_iter_advance(iter, ret); return ret; } @@ -2519,6 +2522,65 @@ static ssize_t smb_extract_kvec_to_rdma(struct iov_iter *iter, 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 - ret, fsize - offset); + + if (!smb_set_sge(rdma, folio_page(folio, 0), offset, part)) + return -EIO; + + offset += part; + ret += 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; } @@ -2563,6 +2625,8 @@ static ssize_t smb_extract_xarray_to_rdma(struct iov_iter *iter, } rcu_read_unlock(); + if (ret > 0) + iov_iter_advance(iter, ret); return ret; } @@ -2590,6 +2654,9 @@ static ssize_t smb_extract_iter_to_rdma(struct iov_iter *iter, size_t len, 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; case ITER_XARRAY: ret = smb_extract_xarray_to_rdma(iter, rdma, len); break; @@ -2598,9 +2665,7 @@ static ssize_t smb_extract_iter_to_rdma(struct iov_iter *iter, size_t len, return -EIO; } - if (ret > 0) { - iov_iter_advance(iter, ret); - } else if (ret < 0) { + if (ret < 0) { while (rdma->nr_sge > before) { struct ib_sge *sge = &rdma->sge[rdma->nr_sge--];