From: Ira Weiny <ira.weiny@xxxxxxxxx> kmap() is being deprecated and will break uses of device dax after PKS protection is introduced.[1] The use of kmap() in siw_tx_hdt() is all thread local therefore kmap_local_page() is a sufficient replacement and will work with pgmap protected pages when those are implemented. kmap_local_page() mappings are tracked in a stack and must be unmapped in the opposite order they were mapped in. siw_tx_hdt() tracks pages used in a page_array. It uses that array to unmap pages which were mapped on function exit. Not all entries in the array are mapped and this is tracked in kmap_mask. kunmap_local() takes a mapped address rather than a page. Declare a mapped address array, page_array_addr, of the same size as the page array to be used for unmapping. Use kmap_local_page() instead of kmap() to map pages in the page_array. Because segments are mapped into the page array in increasing index order, modify siw_unmap_pages() to unmap pages in decreasing order. The kmap_mask is no longer needed as the lack of an address in the address array can indicate no unmap is required. [1] https://lore.kernel.org/lkml/20201009195033.3208459-59-ira.weiny@xxxxxxxxx/ Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx> --- drivers/infiniband/sw/siw/siw_qp_tx.c | 35 +++++++++++++++------------ 1 file changed, 20 insertions(+), 15 deletions(-) diff --git a/drivers/infiniband/sw/siw/siw_qp_tx.c b/drivers/infiniband/sw/siw/siw_qp_tx.c index db68a10d12cd..e70aba23f6e7 100644 --- a/drivers/infiniband/sw/siw/siw_qp_tx.c +++ b/drivers/infiniband/sw/siw/siw_qp_tx.c @@ -396,13 +396,17 @@ static int siw_0copy_tx(struct socket *s, struct page **page, #define MAX_TRAILER (MPA_CRC_SIZE + 4) -static void siw_unmap_pages(struct page **pp, unsigned long kmap_mask) +static void siw_unmap_pages(void **addrs, int len) { - while (kmap_mask) { - if (kmap_mask & BIT(0)) - kunmap(*pp); - pp++; - kmap_mask >>= 1; + int i; + + /* + * Work backwards through the array to honor the kmap_local_page() + * ordering requirements. + */ + for (i = (len-1); i >= 0; i--) { + if (addrs[i]) + kunmap_local(addrs[i]); } } @@ -427,13 +431,15 @@ static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s) struct siw_sge *sge = &wqe->sqe.sge[c_tx->sge_idx]; struct kvec iov[MAX_ARRAY]; struct page *page_array[MAX_ARRAY]; + void *page_array_addr[MAX_ARRAY]; struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_EOR }; int seg = 0, do_crc = c_tx->do_crc, is_kva = 0, rv; unsigned int data_len = c_tx->bytes_unsent, hdr_len = 0, trl_len = 0, sge_off = c_tx->sge_off, sge_idx = c_tx->sge_idx, pbl_idx = c_tx->pbl_idx; - unsigned long kmap_mask = 0L; + + memset(page_array_addr, 0, sizeof(page_array_addr)); if (c_tx->state == SIW_SEND_HDR) { if (c_tx->use_sendpage) { @@ -498,7 +504,7 @@ static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s) p = siw_get_upage(mem->umem, sge->laddr + sge_off); if (unlikely(!p)) { - siw_unmap_pages(page_array, kmap_mask); + siw_unmap_pages(page_array_addr, MAX_ARRAY); wqe->processed -= c_tx->bytes_unsent; rv = -EFAULT; goto done_crc; @@ -506,11 +512,10 @@ static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s) page_array[seg] = p; if (!c_tx->use_sendpage) { - iov[seg].iov_base = kmap(p) + fp_off; - iov[seg].iov_len = plen; + page_array_addr[seg] = kmap_local_page(page_array[seg]); - /* Remember for later kunmap() */ - kmap_mask |= BIT(seg); + iov[seg].iov_base = page_array_addr[seg] + fp_off; + iov[seg].iov_len = plen; if (do_crc) crypto_shash_update( @@ -518,7 +523,7 @@ static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s) iov[seg].iov_base, plen); } else if (do_crc) { - kaddr = kmap_local_page(p); + kaddr = kmap_local_page(page_array[seg]); crypto_shash_update(c_tx->mpa_crc_hd, kaddr + fp_off, plen); @@ -542,7 +547,7 @@ static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s) if (++seg > (int)MAX_ARRAY) { siw_dbg_qp(tx_qp(c_tx), "to many fragments\n"); - siw_unmap_pages(page_array, kmap_mask); + siw_unmap_pages(page_array_addr, MAX_ARRAY); wqe->processed -= c_tx->bytes_unsent; rv = -EMSGSIZE; goto done_crc; @@ -593,7 +598,7 @@ static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s) } else { rv = kernel_sendmsg(s, &msg, iov, seg + 1, hdr_len + data_len + trl_len); - siw_unmap_pages(page_array, kmap_mask); + siw_unmap_pages(page_array_addr, MAX_ARRAY); } if (rv < (int)hdr_len) { /* Not even complete hdr pushed or negative rv */ -- 2.28.0.rc0.12.gb6a658bd00c9
