From: Ira Weiny <ira.weiny@intel.com>
Date: Thu, 24 Jun 2021 10:48:14 -0700
Subject: RDMA/siw: Convert siw_tx_hdt() to kmap_local_page()
Patch-mainline: v5.15-rc1
Git-commit: 9d649d594f3965cbd162121259b2f84928b907a1
References: jsc#SLE-19249
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.
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. Alter
siw_unmap_pages() to take the iov array to reuse the iov_base address of
each mapping. Use PAGE_MASK to get the proper address for kunmap_local().
kmap_local_page() mappings are tracked in a stack and must be unmapped in
the opposite order they were mapped in. Because segments are mapped into
the page array in increasing index order, modify siw_unmap_pages() to
unmap pages in decreasing order.
Use kmap_local_page() instead of kmap() to map pages in the page_array.
[1] https://lore.kernel.org/lkml/20201009195033.3208459-59-ira.weiny@intel.com/
Link: https://lore.kernel.org/r/20210624174814.2822896-1-ira.weiny@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Bernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/infiniband/sw/siw/siw_qp_tx.c | 30 +++++++++++++++++++-----------
1 file changed, 19 insertions(+), 11 deletions(-)
--- a/drivers/infiniband/sw/siw/siw_qp_tx.c
+++ b/drivers/infiniband/sw/siw/siw_qp_tx.c
@@ -396,13 +396,20 @@ static int siw_0copy_tx(struct socket *s
#define MAX_TRAILER (MPA_CRC_SIZE + 4)
-static void siw_unmap_pages(struct page **pp, unsigned long kmap_mask)
+static void siw_unmap_pages(struct kvec *iov, unsigned long kmap_mask, 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 (kmap_mask & BIT(i)) {
+ unsigned long addr = (unsigned long)iov[i].iov_base;
+
+ kunmap_local((void *)(addr & PAGE_MASK));
+ }
}
}
@@ -498,7 +505,7 @@ static int siw_tx_hdt(struct siw_iwarp_t
p = siw_get_upage(mem->umem,
sge->laddr + sge_off);
if (unlikely(!p)) {
- siw_unmap_pages(page_array, kmap_mask);
+ siw_unmap_pages(iov, kmap_mask, seg);
wqe->processed -= c_tx->bytes_unsent;
rv = -EFAULT;
goto done_crc;
@@ -506,11 +513,12 @@ static int siw_tx_hdt(struct siw_iwarp_t
page_array[seg] = p;
if (!c_tx->use_sendpage) {
- iov[seg].iov_base = kmap(p) + fp_off;
- iov[seg].iov_len = plen;
+ void *kaddr = kmap_local_page(p);
/* Remember for later kunmap() */
kmap_mask |= BIT(seg);
+ iov[seg].iov_base = kaddr + fp_off;
+ iov[seg].iov_len = plen;
if (do_crc)
crypto_shash_update(
@@ -542,7 +550,7 @@ static int siw_tx_hdt(struct siw_iwarp_t
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(iov, kmap_mask, seg-1);
wqe->processed -= c_tx->bytes_unsent;
rv = -EMSGSIZE;
goto done_crc;
@@ -593,7 +601,7 @@ sge_done:
} 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(iov, kmap_mask, seg);
}
if (rv < (int)hdr_len) {
/* Not even complete hdr pushed or negative rv */