diff --git a/src/gallium/drivers/radeonsi/si_buffer.c b/src/gallium/drivers/radeonsi/si_buffer.c
index 33ce616d21d..1d0673f9362 100644
--- a/src/gallium/drivers/radeonsi/si_buffer.c
+++ b/src/gallium/drivers/radeonsi/si_buffer.c
@@ -657,31 +657,57 @@ static struct pipe_resource *si_buffer_from_user_memory(struct pipe_screen *scre
 struct pipe_resource *si_buffer_from_winsys_buffer(struct pipe_screen *screen,
                                                    const struct pipe_resource *templ,
                                                    struct pb_buffer *imported_buf,
-                                                   bool dedicated)
+                                                   uint64_t offset)
 {
+   if (offset + templ->width0 > imported_buf->size)
+      return NULL;
+
    struct si_screen *sscreen = (struct si_screen *)screen;
    struct si_resource *res = si_alloc_buffer_struct(screen, templ, false);
 
    if (!res)
-      return 0;
+      return NULL;
 
-   res->buf = imported_buf;
-   res->gpu_address = sscreen->ws->buffer_get_virtual_address(res->buf);
-   res->bo_size = imported_buf->size;
-   res->bo_alignment_log2 = imported_buf->alignment_log2;
-   res->domains = sscreen->ws->buffer_get_initial_domain(res->buf);
+   enum radeon_bo_domain domains = sscreen->ws->buffer_get_initial_domain(res->buf);
 
-   res->memory_usage_kb = MAX2(1, res->bo_size / 1024);
+   /* Get or guess the BO flags. */
+   unsigned flags = RADEON_FLAG_NO_SUBALLOC;
 
    if (sscreen->ws->buffer_get_flags)
-      res->flags = sscreen->ws->buffer_get_flags(res->buf);
+      res->flags |= sscreen->ws->buffer_get_flags(res->buf);
+   else
+      flags |= RADEON_FLAG_GTT_WC; /* unknown flags, guess them */
 
-   if (templ->flags & PIPE_RESOURCE_FLAG_SPARSE) {
-      res->b.b.flags |= SI_RESOURCE_FLAG_UNMAPPABLE;
-      res->flags |= RADEON_FLAG_SPARSE;
+   /* Deduce the usage. */
+   switch (domains) {
+   case RADEON_DOMAIN_VRAM:
+   case RADEON_DOMAIN_VRAM_GTT:
+      res->b.b.usage = PIPE_USAGE_DEFAULT;
+      break;
+
+   default:
+      /* Other values are interpreted as GTT. */
+      domains = RADEON_DOMAIN_GTT;
+
+      if (flags & RADEON_FLAG_GTT_WC)
+         res->b.b.usage = PIPE_USAGE_STREAM;
+      else
+         res->b.b.usage = PIPE_USAGE_STAGING;
    }
 
+   si_init_resource_fields(sscreen, res, imported_buf->size,
+                           1 << imported_buf->alignment_log2);
+
+   res->b.is_shared = true;
    res->b.buffer_id_unique = util_idalloc_mt_alloc(&sscreen->buffer_ids);
+   res->buf = imported_buf;
+   res->gpu_address = sscreen->ws->buffer_get_virtual_address(res->buf) + offset;
+   res->domains = domains;
+   res->flags = flags;
+
+   util_range_add((struct pipe_resource *)templ, &res->valid_buffer_range, 0, templ->width0);
+   util_range_add((struct pipe_resource *)templ, &res->b.valid_buffer_range, 0, templ->width0);
+
    return &res->b.b;
 }
 
diff --git a/src/gallium/drivers/radeonsi/si_pipe.h b/src/gallium/drivers/radeonsi/si_pipe.h
index 211ec7f740e..af83efcf0e8 100644
--- a/src/gallium/drivers/radeonsi/si_pipe.h
+++ b/src/gallium/drivers/radeonsi/si_pipe.h
@@ -1333,6 +1333,10 @@ struct pipe_resource *pipe_aligned_buffer_create(struct pipe_screen *screen, uns
                                                  unsigned usage, unsigned size, unsigned alignment);
 struct si_resource *si_aligned_buffer_create(struct pipe_screen *screen, unsigned flags,
                                              unsigned usage, unsigned size, unsigned alignment);
+struct pipe_resource *si_buffer_from_winsys_buffer(struct pipe_screen *screen,
+                                                   const struct pipe_resource *templ,
+                                                   struct pb_buffer *imported_buf,
+                                                   uint64_t offset);
 void si_replace_buffer_storage(struct pipe_context *ctx, struct pipe_resource *dst,
                                struct pipe_resource *src, unsigned num_rebinds,
                                uint32_t rebind_mask, uint32_t delete_buffer_id);
@@ -2037,11 +2041,6 @@ static inline unsigned si_num_vbos_in_user_sgprs(struct si_screen *sscreen)
 #define PRINT_ERR(fmt, args...)                                                                    \
    fprintf(stderr, "EE %s:%d %s - " fmt, __FILE__, __LINE__, __func__, ##args)
 
-struct pipe_resource *si_buffer_from_winsys_buffer(struct pipe_screen *screen,
-                                                   const struct pipe_resource *templ,
-                                                   struct pb_buffer *imported_buf,
-                                                   bool dedicated);
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/gallium/drivers/radeonsi/si_texture.c b/src/gallium/drivers/radeonsi/si_texture.c
index 39a230c8f5c..0d8f293ee93 100644
--- a/src/gallium/drivers/radeonsi/si_texture.c
+++ b/src/gallium/drivers/radeonsi/si_texture.c
@@ -2230,8 +2230,7 @@ static struct pipe_resource *si_resource_from_memobj(struct pipe_screen *screen,
    struct pipe_resource *res;
 
    if (templ->target == PIPE_BUFFER)
-      res = si_buffer_from_winsys_buffer(screen, templ, memobj->buf,
-                                         memobj->b.dedicated);
+      res = si_buffer_from_winsys_buffer(screen, templ, memobj->buf, offset);
    else
       res = si_texture_from_winsys_buffer(sscreen, templ, memobj->buf,
                                           memobj->stride,