- iommu_merge = 1;
-
- while (*p) {
- if (!strncmp(p,"off",3))
- no_iommu = 1;
- /* gart_parse_options has more force support */
- if (!strncmp(p,"force",5))
- force_iommu = 1;
- if (!strncmp(p,"noforce",7)) {
- iommu_merge = 0;
- force_iommu = 0;
- }
-
- if (!strncmp(p, "biomerge",8)) {
- iommu_bio_merge = 4096;
- iommu_merge = 1;
- force_iommu = 1;
- }
- if (!strncmp(p, "panic",5))
- panic_on_overflow = 1;
- if (!strncmp(p, "nopanic",7))
- panic_on_overflow = 0;
- if (!strncmp(p, "merge",5)) {
- iommu_merge = 1;
- force_iommu = 1;
- }
- if (!strncmp(p, "nomerge",7))
- iommu_merge = 0;
- if (!strncmp(p, "forcesac",8))
- iommu_sac_force = 1;
+ iommu_merge = 1;
+
+ if (!p)
+ return -EINVAL;
+
+ while (*p) {
+ if (!strncmp(p,"off",3))
+ no_iommu = 1;
+ /* gart_parse_options has more force support */
+ if (!strncmp(p,"force",5))
+ force_iommu = 1;
+ if (!strncmp(p,"noforce",7)) {
+ iommu_merge = 0;
+ force_iommu = 0;
+ }
+
+ if (!strncmp(p, "biomerge",8)) {
+ iommu_bio_merge = 4096;
+ iommu_merge = 1;
+ force_iommu = 1;
+ }
+ if (!strncmp(p, "panic",5))
+ panic_on_overflow = 1;
+ if (!strncmp(p, "nopanic",7))
+ panic_on_overflow = 0;
+ if (!strncmp(p, "merge",5)) {
+ iommu_merge = 1;
+ force_iommu = 1;
+ }
+ if (!strncmp(p, "nomerge",7))
+ iommu_merge = 0;
+ if (!strncmp(p, "forcesac",8))
+ iommu_sac_force = 1;
+ if (!strncmp(p, "allowdac", 8))
+ forbid_dac = 0;
+ if (!strncmp(p, "nodac", 5))
+ forbid_dac = -1;