pipe-loader: move dup(fd) within pipe_loader_drm_probe_fd

Currently pipe_loader_drm_probe_fd takes ownership of the fd given.
To match that, pipe_loader_release closes it.

Yet we have many instances which do not want the change of ownership,
and thus duplicate the fd before passing it to the pipe-loader.

Move the dup() within pipe-loader, explicitly document that and document
all the cases through the codebase.

A trivial git grep -2 pipe_loader_release makes things as obvious as it
gets ;-)

Cc: Leo Liu <[email protected]>
Cc: Thomas Hellstrom <[email protected]>
Cc: Axel Davy <[email protected]>
Cc: Patrick Rudolph <[email protected]>
Signed-off-by: Emil Velikov <[email protected]>
Reviewed-by: Thomas Hellstrom <[email protected]>
Reviewed-by: Axel Davy <[email protected]> (for nine)

3 files changed, 6 insertions, 26 deletions

diff --git a/src/gallium/state_trackers/dri/dri2.c b/src/gallium/state_trackers/dri/dri2.c
index 20540e39881..b17c5e16ede 100644
--- a/src/gallium/state_trackers/dri/dri2.c
+++ b/src/gallium/state_trackers/dri/dri2.c
@@ -29,7 +29,6 @@
  */
 
 #include <xf86drm.h>
-#include <fcntl.h>
 #include "GL/mesa_glinterop.h"
 #include "util/u_memory.h"
 #include "util/u_inlines.h"
@@ -2103,7 +2102,6 @@ dri2_init_screen(__DRIscreen * sPriv)
    struct pipe_screen *pscreen = NULL;
    const struct drm_conf_ret *throttle_ret;
    const struct drm_conf_ret *dmabuf_ret;
-   int fd;
 
    screen = CALLOC_STRUCT(dri_screen);
    if (!screen)
@@ -2115,11 +2113,7 @@ dri2_init_screen(__DRIscreen * sPriv)
 
    sPriv->driverPrivate = (void *)screen;
 
-   if (screen->fd < 0 || (fd = fcntl(screen->fd, F_DUPFD_CLOEXEC, 3)) < 0)
-      goto free_screen;
-
-
-   if (pipe_loader_drm_probe_fd(&screen->dev, fd)) {
+   if (pipe_loader_drm_probe_fd(&screen->dev, screen->fd)) {
       dri_init_options(screen);
 
       pscreen = pipe_loader_create_screen(screen->dev);
@@ -2180,10 +2174,7 @@ destroy_screen:
 release_pipe:
    if (screen->dev)
       pipe_loader_release(&screen->dev, 1);
-   else
-      close(fd);
 
-free_screen:
    FREE(screen);
    return NULL;
 }
@@ -2212,10 +2203,7 @@ dri_kms_init_screen(__DRIscreen * sPriv)
 
    sPriv->driverPrivate = (void *)screen;
 
-   if (screen->fd < 0 || (fd = fcntl(screen->fd, F_DUPFD_CLOEXEC, 3)) < 0)
-      goto free_screen;
-
-   if (pipe_loader_sw_probe_kms(&screen->dev, fd)) {
+   if (pipe_loader_sw_probe_kms(&screen->dev, screen->fd)) {
       dri_init_options(screen);
       pscreen = pipe_loader_create_screen(screen->dev);
    }
@@ -2257,10 +2245,7 @@ destroy_screen:
 release_pipe:
    if (screen->dev)
       pipe_loader_release(&screen->dev, 1);
-   else
-      close(fd);
 
-free_screen:
    FREE(screen);
 #endif // GALLIUM_SOFTPIPE
    return NULL;
diff --git a/src/gallium/state_trackers/dri/dri_screen.c b/src/gallium/state_trackers/dri/dri_screen.c
index 308e23685e8..82a0988a634 100644
--- a/src/gallium/state_trackers/dri/dri_screen.c
+++ b/src/gallium/state_trackers/dri/dri_screen.c
@@ -488,6 +488,7 @@ dri_destroy_screen(__DRIscreen * sPriv)
 
    pipe_loader_release(&screen->dev, 1);
 
+   /* The caller in dri_util preserves the fd ownership */
    free(screen);
    sPriv->driverPrivate = NULL;
    sPriv->extensions = NULL;
diff --git a/src/gallium/state_trackers/xa/xa_tracker.c b/src/gallium/state_trackers/xa/xa_tracker.c
index c046a3a7097..d07cd146af9 100644
--- a/src/gallium/state_trackers/xa/xa_tracker.c
+++ b/src/gallium/state_trackers/xa/xa_tracker.c
@@ -27,7 +27,6 @@
  */
 
 #include <unistd.h>
-#include <fcntl.h>
 #include "xa_tracker.h"
 #include "xa_priv.h"
 #include "pipe/p_state.h"
@@ -153,15 +152,11 @@ xa_tracker_create(int drm_fd)
     struct xa_tracker *xa = calloc(1, sizeof(struct xa_tracker));
     enum xa_surface_type stype;
     unsigned int num_formats;
-    int fd;
 
     if (!xa)
 	return NULL;
 
-    if (drm_fd < 0 || (fd = fcntl(drm_fd, F_DUPFD_CLOEXEC, 3)) < 0)
-	goto out_no_fd;
-
-    if (pipe_loader_drm_probe_fd(&xa->dev, fd))
+    if (pipe_loader_drm_probe_fd(&xa->dev, drm_fd))
 	xa->screen = pipe_loader_create_screen(xa->dev);
 
     if (!xa->screen)
@@ -213,9 +208,7 @@ xa_tracker_create(int drm_fd)
  out_no_screen:
     if (xa->dev)
 	pipe_loader_release(&xa->dev, 1);
-    else
-	close(fd);
- out_no_fd:
+
     free(xa);
     return NULL;
 }
@@ -227,6 +220,7 @@ xa_tracker_destroy(struct xa_tracker *xa)
     xa_context_destroy(xa->default_ctx);
     xa->screen->destroy(xa->screen);
     pipe_loader_release(&xa->dev, 1);
+    /* CHECK: The XA API user preserves ownership of the original fd */
     free(xa);
 }