drm/xe/pf: Add helper to retrieve VF's LMEM object

Instead of accessing VF's lmem_obj directly, introduce a helper function
to make the access more convenient.

Signed-off-by: Lukasz Laguna <lukasz.laguna@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patch.msgid.link/20251112132220.516975-21-michal.winiarski@intel.com
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>

Author: lukaszlaguna

drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c

@@ -1692,6 +1692,32 @@ int xe_gt_sriov_pf_config_bulk_set_lmem(struct xe_gt *gt, unsigned int vfid,
 					   "LMEM", n, err);
 }
 
+static struct xe_bo *pf_get_vf_config_lmem_obj(struct xe_gt *gt, unsigned int vfid)
+{
+	struct xe_gt_sriov_config *config = pf_pick_vf_config(gt, vfid);
+
+	return config->lmem_obj;
+}
+
+/**
+ * xe_gt_sriov_pf_config_get_lmem_obj() - Take a reference to the struct &xe_bo backing VF LMEM.
+ * @gt: the &xe_gt
+ * @vfid: the VF identifier (can't be 0)
+ *
+ * This function can only be called on PF.
+ * The caller is responsible for calling xe_bo_put() on the returned object.
+ *
+ * Return: pointer to struct &xe_bo backing VF LMEM (if any).
+ */
+struct xe_bo *xe_gt_sriov_pf_config_get_lmem_obj(struct xe_gt *gt, unsigned int vfid)
+{
+	xe_gt_assert(gt, vfid);
+
+	guard(mutex)(xe_gt_sriov_pf_master_mutex(gt));
+
+	return xe_bo_get(pf_get_vf_config_lmem_obj(gt, vfid));
+}
+
 static u64 pf_query_free_lmem(struct xe_gt *gt)
 {
 	struct xe_tile *tile = gt->tile;

drivers/gpu/drm/xe/xe_gt_sriov_pf_config.h

@@ -36,6 +36,7 @@ int xe_gt_sriov_pf_config_set_lmem(struct xe_gt *gt, unsigned int vfid, u64 size
 int xe_gt_sriov_pf_config_set_fair_lmem(struct xe_gt *gt, unsigned int vfid, unsigned int num_vfs);
 int xe_gt_sriov_pf_config_bulk_set_lmem(struct xe_gt *gt, unsigned int vfid, unsigned int num_vfs,
 					u64 size);
+struct xe_bo *xe_gt_sriov_pf_config_get_lmem_obj(struct xe_gt *gt, unsigned int vfid);
 
 u32 xe_gt_sriov_pf_config_get_exec_quantum(struct xe_gt *gt, unsigned int vfid);
 int xe_gt_sriov_pf_config_set_exec_quantum(struct xe_gt *gt, unsigned int vfid, u32 exec_quantum);