gru: support contexts with zero dsrs or cbrs

Support alocation of GRU contexts that contain zero DSR or CBR resources.
Some instructions do not require DSR resources.  Contexts without CBR
resources are useful for diagnostics.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/misc/sgi-gru/grufile.c b/drivers/misc/sgi-gru/grufile.c
index 9e6da46eeb04043030d79a9ae91a884771afdf9d..b1567ce868e9d5f289acf664ff2f28bbfdd42de4 100644 (file)
--- a/drivers/misc/sgi-gru/grufile.c
+++ b/drivers/misc/sgi-gru/grufile.c
@@ -135,11 +135,9 @@ static int gru_create_new_context(unsigned long arg)
        if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
                return -EFAULT;
 
-       if (req.data_segment_bytes == 0 ||
-                               req.data_segment_bytes > max_user_dsr_bytes)
+       if (req.data_segment_bytes > max_user_dsr_bytes)
                return -EINVAL;
-       if (!req.control_blocks || !req.maximum_thread_count ||
-                               req.control_blocks > max_user_cbrs)
+       if (req.control_blocks > max_user_cbrs || !req.maximum_thread_count)
                return -EINVAL;
 
        if (!(req.options & GRU_OPT_MISS_MASK))

diff --git a/drivers/misc/sgi-gru/grumain.c b/drivers/misc/sgi-gru/grumain.c
index 3398e54a762be43c1e5992435e835d5f0f1e9e2d..4e6e8c3554f009e1a0cb909226b1f6cc0389be24 100644 (file)
--- a/drivers/misc/sgi-gru/grumain.c
+++ b/drivers/misc/sgi-gru/grumain.c
@@ -150,7 +150,7 @@ static unsigned long reserve_resources(unsigned long *p, int n, int mmax,
        unsigned long bits = 0;
        int i;
 
-       do {
+       while (n--) {
                i = find_first_bit(p, mmax);
                if (i == mmax)
                        BUG();
@@ -158,7 +158,7 @@ static unsigned long reserve_resources(unsigned long *p, int n, int mmax,
                __set_bit(i, &bits);
                if (idx)
                        *idx++ = i;
-       } while (--n);
+       }
        return bits;
 }