To avoid racing with other user memory reservations, immediately
account full amount of pages to be pinned.
Fixes: 2251334dcac9 ("rdma/siw: application buffer management")
Reported-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Suggested-by: Alistair Popple <apopple@xxxxxxxxxx>
Signed-off-by: Bernard Metzler <bmt@xxxxxxxxxxxxxx>
---
drivers/infiniband/sw/siw/siw_mem.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/infiniband/sw/siw/siw_mem.c b/drivers/infiniband/sw/siw/siw_mem.c
index b2b33dd3b4fa..7afdbe3f2266 100644
--- a/drivers/infiniband/sw/siw/siw_mem.c
+++ b/drivers/infiniband/sw/siw/siw_mem.c
@@ -398,7 +398,7 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable)
mlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
- if (num_pages + atomic64_read(&mm_s->pinned_vm) > mlock_limit) {
+ if (atomic64_add_return(num_pages, &mm_s->pinned_vm) > mlock_limit) {
rv = -ENOMEM;
goto out_sem_up;
}
@@ -429,7 +429,6 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable)
goto out_sem_up;
umem->num_pages += rv;
- atomic64_add(rv, &mm_s->pinned_vm);
first_page_va += rv * PAGE_SIZE;
nents -= rv;
got += rv;
@@ -442,6 +441,10 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable)
if (rv > 0)
return umem;
+ /* Adjust accounting for pages not pinned */
+ if (num_pages)
+ atomic64_sub(num_pages, &mm_s->pinned_vm);
+
siw_umem_release(umem, false);
return ERR_PTR(rv);
--
2.32.0
