[src/trunk]: src/sys/dev/pci Fix error branches in agp_amd64.c.

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5526ac0d28a7
branches:  trunk
changeset: 337151:5526ac0d28a7
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sat Apr 04 15:08:40 2015 +0000

description:
Fix error branches in agp_amd64.c.

- agp_generic_detach always.
- Free asc if it was allocated.  (Found by Brainy, noted by maxv@.)
- Free the GATT if it was allocated.

diffstat:

 sys/dev/pci/agp_amd64.c |  45 ++++++++++++++++++++++++++++++++-------------
 1 files changed, 32 insertions(+), 13 deletions(-)

diffs (111 lines):

diff -r aa95fbdbf99f -r 5526ac0d28a7 sys/dev/pci/agp_amd64.c
--- a/sys/dev/pci/agp_amd64.c   Sat Apr 04 14:19:00 2015 +0000
+++ b/sys/dev/pci/agp_amd64.c   Sat Apr 04 15:08:40 2015 +0000
@@ -25,7 +25,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: agp_amd64.c,v 1.7 2012/02/25 21:21:09 tsutsui Exp $");
+__KERNEL_RCSID(0, "$NetBSD: agp_amd64.c,v 1.8 2015/04/04 15:08:40 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -206,17 +206,19 @@
        pcitag_t tag;
        pcireg_t id, attbase, apctrl;
        int maxdevs, i, n;
+       int error;
 
        asc = malloc(sizeof(struct agp_amd64_softc), M_AGP, M_NOWAIT | M_ZERO);
        if (asc == NULL) {
                aprint_error(": can't allocate softc\n");
-               return ENOMEM;
+               error = ENOMEM;
+               goto fail0;
        }
 
        if (agp_map_aperture(pa, sc, AGP_APBASE) != 0) {
                aprint_error(": can't map aperture\n");
-               free(asc, M_AGP);
-               return ENXIO;
+               error = ENXIO;
+               goto fail1;
        }
 
        maxdevs = pci_bus_maxdevs(pa->pa_pc, 0);
@@ -232,7 +234,8 @@
        }
        if (n == 0) {
                aprint_error(": No Miscellaneous Control unit found.\n");
-               return ENXIO;
+               error = ENXIO;
+               goto fail1;
        }
        asc->n_mctrl = n;
 
@@ -256,8 +259,8 @@
                 * aperture so that the gatt size reduces.
                 */
                if (AGP_SET_APERTURE(sc, AGP_GET_APERTURE(sc) / 2)) {
-                       agp_generic_detach(sc);
-                       return ENOMEM;
+                       error = ENOMEM;
+                       goto fail1;
                }
        }
        asc->gatt = gatt;
@@ -265,15 +268,21 @@
        switch (PCI_VENDOR(sc->as_id)) {
        case PCI_VENDOR_ALI:
                agp_amd64_uli_init(sc);
-               if (agp_amd64_uli_set_aperture(sc, asc->initial_aperture))
-                       return ENXIO;
+               if (agp_amd64_uli_set_aperture(sc, asc->initial_aperture)) {
+                       /* XXX Back out agp_amd64_uli_init?  */
+                       error = ENXIO;
+                       goto fail2;
+               }
                break;
 
        case PCI_VENDOR_NVIDIA:
                asc->ctrl_tag = AGP_AMD64_NVIDIA_PCITAG(pa->pa_pc);
                agp_amd64_nvidia_init(sc);
-               if (agp_amd64_nvidia_set_aperture(sc, asc->initial_aperture))
-                       return ENXIO;
+               if (agp_amd64_nvidia_set_aperture(sc, asc->initial_aperture)) {
+                       /* XXX Back out agp_amd64_nvidia_init?  */
+                       error = ENXIO;
+                       goto fail2;
+               }
                break;
 
        case PCI_VENDOR_VIATECH:
@@ -282,8 +291,11 @@
                        asc->ctrl_tag = AGP_AMD64_VIA_PCITAG(pa->pa_pc);
                        agp_amd64_via_init(sc);
                        if (agp_amd64_via_set_aperture(sc,
-                           asc->initial_aperture))
-                               return ENXIO;
+                           asc->initial_aperture)) {
+                               /* XXX Back out agp_amd64_via_init?  */
+                               error = ENXIO;
+                               goto fail2;
+                       }
                }
                break;
        }
@@ -304,7 +316,14 @@
 
        agp_flush_cache();
 
+       /* Success!  */
        return 0;
+
+fail2: agp_free_gatt(sc, gatt);
+fail1: free(asc, M_AGP);
+fail0: agp_generic_detach(sc);
+       KASSERT(error);
+       return error;
 }