Make the validation function a boolean operating on a buffer of given size, removing the extra pointer dances.
Move the OpRegion based VBT validation to intel_opregion_setup(), only initializing opregion->vbt if it's valid. Signed-off-by: Jani Nikula <[email protected]> --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/intel_bios.c | 63 ++++++++++++++++++----------------- drivers/gpu/drm/i915/intel_opregion.c | 9 +++-- 3 files changed, 40 insertions(+), 33 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index a2bd4c6a86a1..ef15f1710b50 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -3354,6 +3354,7 @@ extern void intel_i2c_reset(struct drm_device *dev); /* intel_bios.c */ int intel_bios_init(struct drm_device *dev); +bool intel_bios_is_valid_vbt(const void *buf, size_t size); /* intel_opregion.c */ #ifdef CONFIG_ACPI diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c index f2b79b7d12b8..007b2b759600 100644 --- a/drivers/gpu/drm/i915/intel_bios.c +++ b/drivers/gpu/drm/i915/intel_bios.c @@ -1221,37 +1221,40 @@ static const struct bdb_header *get_bdb_header(const struct vbt_header *vbt) return _vbt + vbt->bdb_offset; } -static const struct vbt_header *validate_vbt(const void *base, - size_t size, - const void *_vbt) +/** + * intel_bios_is_valid_vbt - does the given buffer contain a valid VBT + * @buf: pointer to a buffer to validate + * @size: size of the buffer + * + * Returns true on valid VBT. + */ +bool intel_bios_is_valid_vbt(const void *buf, size_t size) { - size_t offset = _vbt - base; - const struct vbt_header *vbt = _vbt; + const struct vbt_header *vbt = buf; const struct bdb_header *bdb; if (!vbt) - return NULL; + return false; - if (offset + sizeof(struct vbt_header) > size) { + if (sizeof(struct vbt_header) > size) { DRM_DEBUG_DRIVER("VBT header incomplete\n"); - return NULL; + return false; } if (memcmp(vbt->signature, "$VBT", 4)) { DRM_DEBUG_DRIVER("VBT invalid signature\n"); - return NULL; + return false; } - offset += vbt->bdb_offset; - if (offset + sizeof(struct bdb_header) > size) { + if (vbt->bdb_offset + sizeof(struct bdb_header) > size) { DRM_DEBUG_DRIVER("BDB header incomplete\n"); - return NULL; + return false; } bdb = get_bdb_header(vbt); - if (offset + bdb->bdb_size > size) { + if (vbt->bdb_offset + bdb->bdb_size > size) { DRM_DEBUG_DRIVER("BDB incomplete\n"); - return NULL; + return false; } return vbt; @@ -1259,26 +1262,27 @@ static const struct vbt_header *validate_vbt(const void *base, static const struct vbt_header *find_vbt(void __iomem *bios, size_t size) { - const struct vbt_header *vbt = NULL; size_t i; /* Scour memory looking for the VBT signature. */ for (i = 0; i + 4 < size; i++) { - if (ioread32(bios + i) == *((const u32 *) "$VBT")) { - /* - * This is the one place where we explicitly discard the - * address space (__iomem) of the BIOS/VBT. From now on - * everything is based on 'base', and treated as regular - * memory. - */ - void *_bios = (void __force *) bios; + void *vbt; - vbt = validate_vbt(_bios, size, _bios + i); - break; - } + if (ioread32(bios + i) != *((const u32 *) "$VBT")) + continue; + + /* + * This is the one place where we explicitly discard the address + * space (__iomem) of the BIOS/VBT. + */ + vbt = (void __force *) bios + i; + if (intel_bios_is_valid_vbt(vbt, size - i)) + return vbt; + + break; } - return vbt; + return NULL; } /** @@ -1295,7 +1299,7 @@ intel_bios_init(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; struct pci_dev *pdev = dev->pdev; - const struct vbt_header *vbt; + const struct vbt_header *vbt = dev_priv->opregion.vbt; const struct bdb_header *bdb; u8 __iomem *bios = NULL; @@ -1304,9 +1308,6 @@ intel_bios_init(struct drm_device *dev) init_vbt_defaults(dev_priv); - /* XXX Should this validation be moved to intel_opregion.c? */ - vbt = validate_vbt(dev_priv->opregion.header, OPREGION_SIZE, - dev_priv->opregion.vbt); if (vbt) { DRM_DEBUG_KMS("Using VBT from ACPI OpRegion: %20s\n", vbt->signature); diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c index 5b9fc790d300..9f992e7c6185 100644 --- a/drivers/gpu/drm/i915/intel_opregion.c +++ b/drivers/gpu/drm/i915/intel_opregion.c @@ -986,8 +986,13 @@ int intel_opregion_setup(struct drm_device *dev) if (mboxes & MBOX_ASLE_EXT) DRM_DEBUG_DRIVER("ASLE extension supported\n"); - if (!dmi_check_system(intel_no_opregion_vbt)) - opregion->vbt = base + OPREGION_VBT_OFFSET; + if (!dmi_check_system(intel_no_opregion_vbt)) { + void *vbt = base + OPREGION_VBT_OFFSET; + u32 vbt_size = OPREGION_SIZE - OPREGION_VBT_OFFSET; + + if (intel_bios_is_valid_vbt(vbt, vbt_size)) + opregion->vbt = vbt; + } return 0; -- 2.1.4 _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
