When a PF is configured in admin-only mode, it is intended for management
only and must not expose workload-facing capabilities to userspace.

Limit the exposed ioctl set in admin-only PF mode to XE_DEVICE_QUERY and
XE_OBSERVATION, and suppress capability-bearing query payloads so that
the userspace cannot discover execution-related device details in this
mode.

Enable admin-only mode with:
echo <B:D:F> | sudo tee /sys/bus/pci/drivers/xe/unbind
sudo mkdir /sys/kernel/config/xe/<B:D:F>
echo yes | sudo tee /sys/kernel/config/xe/<B:D:F>/sriov/admin_only_pf
echo <B:D:F> | sudo tee /sys/bus/pci/drivers/xe/bind

Signed-off-by: Satyanarayana K V P <[email protected]>
Cc: Michal Wajdeczko <[email protected]>
Cc: Rodrigo Vivi <[email protected]>
Cc: Piotr Piórkowski <[email protected]>
Cc: Matthew Brost <[email protected]>
Cc: Thomas Hellström <[email protected]>
Cc: Michał Winiarski <[email protected]>
Cc: Dunajski Bartosz <[email protected]>
Cc: Ashutosh Dixit <[email protected]>
Cc: [email protected]
Acked-by: Rodrigo Vivi <[email protected]>
Acked-by: Ashutosh Dixit <[email protected]>

---
V7 -> V8:
- Fixed issues reported by CI.Hooks
- Updated commit message (Ashutosh)
- Removed gem_prime_import from admin_only_driver structure (Michal)

V6 -> V7:
- Allowed xe_observation_ioctl as well with admin-only PF (Ashutosh,
Michal).
- Updated commit message with steps to enable admin-only mode (Rodrigo).

V5 -> V6:
- Updated commit message.
- Return number of engines and memory regions as zero instead of
returning query size as zero (Michal Wajdeczko).
- Allow all other query IOCTLs excepts query_engines and
query_mem_regions (Michal Wajdeczko).

V4 -> V5:
- Updated commit message (Matt B).
- Introduced new driver_admin_only_pf structure (Michal Wajdeczko).
- Updated all query configs (Michal Wajdeczko).
- Renamed xe_device_is_admin_only() to xe_device_is_admin_only_pf()
- Fixed other review comments (Michal Wajdeczko).

V3 -> V4:
- Suppressed device capabilities in admin-only PF mode. (Wajdeczko)

V2 -> V3:
- Introduced new helper function xe_debugfs_create_files() to create
debugfs entries based on admin_only_pf mode or normal mode.

V1 -> V2:
- Rebased to latest drm-tip.
- Update update_minor_dev() to debugfs_minor_dev().
---
 drivers/gpu/drm/xe/xe_device.c    | 60 ++++++++++++++++++++++++++++---
 drivers/gpu/drm/xe/xe_device.h    |  1 +
 drivers/gpu/drm/xe/xe_hw_engine.c |  3 ++
 drivers/gpu/drm/xe/xe_query.c     | 10 +++++-
 4 files changed, 69 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
index cbce1d0ffe48..eba2fa6dc7d3 100644
--- a/drivers/gpu/drm/xe/xe_device.c
+++ b/drivers/gpu/drm/xe/xe_device.c
@@ -25,6 +25,7 @@
 #include "regs/xe_regs.h"
 #include "xe_bo.h"
 #include "xe_bo_evict.h"
+#include "xe_configfs.h"
 #include "xe_debugfs.h"
 #include "xe_defaults.h"
 #include "xe_devcoredump.h"
@@ -216,6 +217,11 @@ static const struct drm_ioctl_desc xe_ioctls[] = {
                          DRM_RENDER_ALLOW),
 };
 
+static const struct drm_ioctl_desc xe_ioctls_admin_only[] = {
+       DRM_IOCTL_DEF_DRV(XE_DEVICE_QUERY, xe_query_ioctl, DRM_RENDER_ALLOW),
+       DRM_IOCTL_DEF_DRV(XE_OBSERVATION, xe_observation_ioctl, 
DRM_RENDER_ALLOW),
+};
+
 static long xe_drm_ioctl(struct file *file, unsigned int cmd, unsigned long 
arg)
 {
        struct drm_file *file_priv = file->private_data;
@@ -390,7 +396,7 @@ bool xe_is_xe_file(const struct file *file)
        return file->f_op == &xe_driver_fops;
 }
 
-static struct drm_driver driver = {
+static struct drm_driver regular_driver = {
        .driver_features =
            DRIVER_GEM |
            DRIVER_RENDER | DRIVER_SYNCOBJ |
@@ -415,6 +421,38 @@ static struct drm_driver driver = {
        .patchlevel = DRIVER_PATCHLEVEL,
 };
 
+static struct drm_driver admin_only_driver = {
+       .driver_features =
+           DRIVER_GEM | DRIVER_RENDER | DRIVER_GEM_GPUVA,
+       .open = xe_file_open,
+       .postclose = xe_file_close,
+
+       .dumb_create = xe_bo_dumb_create,
+       .dumb_map_offset = drm_gem_ttm_dumb_map_offset,
+#ifdef CONFIG_PROC_FS
+       .show_fdinfo = xe_drm_client_fdinfo,
+#endif
+       .ioctls = xe_ioctls_admin_only,
+       .num_ioctls = ARRAY_SIZE(xe_ioctls_admin_only),
+       .fops = &xe_driver_fops,
+       .name = DRIVER_NAME,
+       .desc = DRIVER_DESC,
+       .major = DRIVER_MAJOR,
+       .minor = DRIVER_MINOR,
+       .patchlevel = DRIVER_PATCHLEVEL,
+};
+
+/**
+ * xe_device_is_admin_only() - Check whether device is admin only or not.
+ * @xe: the &xe_device to check
+ *
+ * Return: true if the device is admin only, false otherwise.
+ */
+bool xe_device_is_admin_only(const struct xe_device *xe)
+{
+       return xe->drm.driver == &admin_only_driver;
+}
+
 static void xe_device_destroy(struct drm_device *dev, void *dummy)
 {
        struct xe_device *xe = to_xe_device(dev);
@@ -439,16 +477,25 @@ static void xe_device_destroy(struct drm_device *dev, 
void *dummy)
 struct xe_device *xe_device_create(struct pci_dev *pdev,
                                   const struct pci_device_id *ent)
 {
+       struct drm_driver *driver = &regular_driver;
        struct xe_device *xe;
        int err;
 
-       xe_display_driver_set_hooks(&driver);
+#ifdef CONFIG_PCI_IOV
+       /*
+        * Since XE device is not initialized yet, read from configfs
+        * directly to decide whether we are in admin-only PF mode or not.
+        */
+       if (xe_configfs_admin_only_pf(pdev))
+               driver = &admin_only_driver;
+#endif
+       xe_display_driver_set_hooks(driver);
 
-       err = aperture_remove_conflicting_pci_devices(pdev, driver.name);
+       err = aperture_remove_conflicting_pci_devices(pdev, driver->name);
        if (err)
                return ERR_PTR(err);
 
-       xe = devm_drm_dev_alloc(&pdev->dev, &driver, struct xe_device, drm);
+       xe = devm_drm_dev_alloc(&pdev->dev, driver, struct xe_device, drm);
        if (IS_ERR(xe))
                return xe;
 
@@ -708,6 +755,11 @@ int xe_device_probe_early(struct xe_device *xe)
 
        xe_sriov_probe_early(xe);
 
+       if (xe_device_is_admin_only(xe) && !IS_SRIOV_PF(xe)) {
+               xe_err(xe, "Can't run Admin-only mode without SR-IOV PF 
mode!\n");
+               return -ENODEV;
+       }
+
        if (IS_SRIOV_VF(xe))
                vf_update_device_info(xe);
 
diff --git a/drivers/gpu/drm/xe/xe_device.h b/drivers/gpu/drm/xe/xe_device.h
index e4b9de8d8e95..c220f2f1352f 100644
--- a/drivers/gpu/drm/xe/xe_device.h
+++ b/drivers/gpu/drm/xe/xe_device.h
@@ -43,6 +43,7 @@ static inline struct xe_device *ttm_to_xe_device(struct 
ttm_device *ttm)
        return container_of(ttm, struct xe_device, ttm);
 }
 
+bool xe_device_is_admin_only(const struct xe_device *xe);
 struct xe_device *xe_device_create(struct pci_dev *pdev,
                                   const struct pci_device_id *ent);
 int xe_device_probe_early(struct xe_device *xe);
diff --git a/drivers/gpu/drm/xe/xe_hw_engine.c 
b/drivers/gpu/drm/xe/xe_hw_engine.c
index 337baf0a6e87..2c324acb1dd0 100644
--- a/drivers/gpu/drm/xe/xe_hw_engine.c
+++ b/drivers/gpu/drm/xe/xe_hw_engine.c
@@ -1027,6 +1027,9 @@ bool xe_hw_engine_is_reserved(struct xe_hw_engine *hwe)
        struct xe_gt *gt = hwe->gt;
        struct xe_device *xe = gt_to_xe(gt);
 
+       if (xe_device_is_admin_only(xe))
+               return true;
+
        if (hwe->class == XE_ENGINE_CLASS_OTHER)
                return true;
 
diff --git a/drivers/gpu/drm/xe/xe_query.c b/drivers/gpu/drm/xe/xe_query.c
index d84d6a422c45..b10a281c6ae0 100644
--- a/drivers/gpu/drm/xe/xe_query.c
+++ b/drivers/gpu/drm/xe/xe_query.c
@@ -231,10 +231,13 @@ static size_t calc_mem_regions_size(struct xe_device *xe)
        u32 num_managers = 1;
        int i;
 
+       if (xe_device_is_admin_only(xe))
+               goto out;
+
        for (i = XE_PL_VRAM0; i <= XE_PL_VRAM1; ++i)
                if (ttm_manager_type(&xe->ttm, i))
                        num_managers++;
-
+out:
        return offsetof(struct drm_xe_query_mem_regions, 
mem_regions[num_managers]);
 }
 
@@ -273,6 +276,8 @@ static int query_mem_regions(struct xe_device *xe,
        mem_regions->num_mem_regions = 1;
 
        for (i = XE_PL_VRAM0; i <= XE_PL_VRAM1; ++i) {
+               if (xe_device_is_admin_only(xe))
+                       break;
                man = ttm_manager_type(&xe->ttm, i);
                if (man) {
                        
mem_regions->mem_regions[mem_regions->num_mem_regions].mem_class =
@@ -297,6 +302,9 @@ static int query_mem_regions(struct xe_device *xe,
                }
        }
 
+       if (xe_device_is_admin_only(xe))
+               memset(mem_regions, 0, size);
+
        if (!copy_to_user(query_ptr, mem_regions, size))
                ret = 0;
        else
-- 
2.43.0

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