sdp: Don't try to allocate FMR larger than RLIMIT_MEMLOCK

During ZCopy. If don't have CAP_IPC_LOCK capability and current
max number of locked pages is smaller than the buffer size, split
the send into small fragments.

Signed-off-by: Amir Vadai <amirv@mellanox.co.il>

diff --git a/drivers/infiniband/ulp/sdp/sdp_zcopy.c b/drivers/infiniband/ulp/sdp/sdp_zcopy.c
index 18a205ffe90b215099183ffed09b8e086eb5e07b..a6f8b14c5b815c7468b0aa1a3457c77d1167bb54 100644 (file)
--- a/drivers/infiniband/ulp/sdp/sdp_zcopy.c
+++ b/drivers/infiniband/ulp/sdp/sdp_zcopy.c
@@ -400,6 +400,20 @@ out:
        return;
 }
 
+static unsigned long sdp_get_max_memlockable_bytes(unsigned long offset)
+{
+       unsigned long avail;
+       unsigned long lock_limit;
+
+       if (capable(CAP_IPC_LOCK))
+               return ULONG_MAX;
+
+       lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+       avail = lock_limit - (current->mm->locked_vm << PAGE_SHIFT);
+
+       return avail - offset;
+}
+
 static int sdp_alloc_fmr(struct sock *sk, void *uaddr, size_t len,
        struct ib_pool_fmr **_fmr, struct ib_umem **_umem)
 {
@@ -410,21 +424,34 @@ static int sdp_alloc_fmr(struct sock *sk, void *uaddr, size_t len,
        struct ib_umem_chunk *chunk;
        int n, j, k;
        int rc = 0;
+       unsigned long max_lockable_bytes;
 
-       if (len > SDP_MAX_RDMA_READ_LEN) {
+       if (unlikely(len > SDP_MAX_RDMA_READ_LEN)) {
                sdp_dbg_data(sk, "len:0x%lx > FMR_SIZE: 0x%lx\n",
                        len, SDP_MAX_RDMA_READ_LEN);
                len = SDP_MAX_RDMA_READ_LEN;
        }
 
-       sdp_dbg_data(sk, "user buf: %p, len:0x%lx\n", uaddr, len);
+       max_lockable_bytes = sdp_get_max_memlockable_bytes((unsigned long)uaddr & ~PAGE_MASK);
+       if (unlikely(len > max_lockable_bytes)) {
+               sdp_dbg_data(sk, "len:0x%lx > RLIMIT_MEMLOCK available: 0x%lx\n",
+                       len, max_lockable_bytes);
+               len = max_lockable_bytes;
+       }
+
+       sdp_dbg_data(sk, "user buf: %p, len:0x%lx max_lockable_bytes: 0x%lx\n",
+                       uaddr, len, max_lockable_bytes);
 
        umem = ib_umem_get(&sdp_sk(sk)->context, (unsigned long)uaddr, len,
                IB_ACCESS_REMOTE_WRITE, 0);
 
        if (IS_ERR(umem)) {
                rc = PTR_ERR(umem);
-               sdp_warn(sk, "Error getting umem: %d\n", rc);
+               sdp_warn(sk, "Error doing umem_get 0x%lx bytes: %d\n", len, rc);
+               sdp_warn(sk, "RLIMIT_MEMLOCK: 0x%lx[cur] 0x%lx[max] CAP_IPC_LOCK: %d\n",
+                               current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur,
+                               current->signal->rlim[RLIMIT_MEMLOCK].rlim_max,
+                               capable(CAP_IPC_LOCK));
                goto err_umem_get;
        }