dmaengine: idxd: Fix default allowed read buffers value in group

Currently default read buffers that is allowed in a group is 0.
grpcfg will be configured to max read buffers that IDXD can support if
the group's allowed read buffers value is 0. But 0 is an invalid
read buffers value and user may get confused when seeing the invalid
initial value 0 through sysfs interface.

To show only valid allowed read buffers value and eliminate confusion,
directly initialize the allowed read buffers to IDXD's max read buffers.
User still can change the value through sysfs interface.

Suggested-by: Ramesh Thomas <ramesh.thomas@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Nikhil Rao <nikhil.rao@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230127192855.966929-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/idxd/device.c b/drivers/dma/idxd/device.c
index 19ab3e5..7516753 100644 (file)
--- a/drivers/dma/idxd/device.c
+++ b/drivers/dma/idxd/device.c
@@ -699,7 +699,11 @@ static void idxd_groups_clear_state(struct idxd_device *idxd)
                group->num_engines = 0;
                group->num_wqs = 0;
                group->use_rdbuf_limit = false;
-               group->rdbufs_allowed = 0;
+               /*
+                * The default value is the same as the value of
+                * total read buffers in GRPCAP.
+                */
+               group->rdbufs_allowed = idxd->max_rdbufs;
                group->rdbufs_reserved = 0;
                if (idxd->hw.version <= DEVICE_VERSION_2 && !tc_override) {
                        group->tc_a = 1;
@@ -934,11 +938,7 @@ static void idxd_group_flags_setup(struct idxd_device *idxd)
                        group->grpcfg.flags.tc_b = group->tc_b;
                group->grpcfg.flags.use_rdbuf_limit = group->use_rdbuf_limit;
                group->grpcfg.flags.rdbufs_reserved = group->rdbufs_reserved;
-               if (group->rdbufs_allowed)
-                       group->grpcfg.flags.rdbufs_allowed = group->rdbufs_allowed;
-               else
-                       group->grpcfg.flags.rdbufs_allowed = idxd->max_rdbufs;
-
+               group->grpcfg.flags.rdbufs_allowed = group->rdbufs_allowed;
                group->grpcfg.flags.desc_progress_limit = group->desc_progress_limit;
                group->grpcfg.flags.batch_progress_limit = group->batch_progress_limit;
        }

diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c
index e63b0c6..640d304 100644 (file)
--- a/drivers/dma/idxd/init.c
+++ b/drivers/dma/idxd/init.c
@@ -302,6 +302,11 @@ static int idxd_setup_groups(struct idxd_device *idxd)
                        group->tc_a = -1;
                        group->tc_b = -1;
                }
+               /*
+                * The default value is the same as the value of
+                * total read buffers in GRPCAP.
+                */
+               group->rdbufs_allowed = idxd->max_rdbufs;
        }
 
        return 0;