On 02-Jul-18 6:26 PM, Alejandro Lucero wrote:
A device can suffer addressing limitations. This functions checks
memsegs have iovas within the supported range based on dma mask.
PMD should use this during initialization if supported devices
suffer addressing limitations, returning an error if this function
returns memsegs out of range.
Another potential usage is for emulated IOMMU hardware with addressing
limitations.
Signed-off-by: Alejandro Lucero <alejandro.luc...@netronome.com>
---
<snip>
+ const struct rte_mem_config *mcfg;
+ uint64_t mask;
+ int i;
+ int ret = 0;
+
+ /* create dma mask */
+ mask = 1ULL << maskbits;
+ mask -= 1;
mask = ~((1ULL << maskbits) - 1);
? IMO this makes it much more clear what you're trying to do.
+
+ /* get pointer to global configuration */
+ mcfg = rte_eal_get_configuration()->mem_config;
+
+ for (i = 0; i < RTE_MAX_MEMSEG; i++) {
+ if (mcfg->memseg[i].addr == NULL)
+ break;
+
+ if (mcfg->memseg[i].iova & ~mask) {
+ ret = -1;
+ break;
+ }
+ }
+
+ if (!ret)
+ return ret;
+
+ RTE_LOG(INFO, EAL, "memseg[%d] iova %"PRIx64" out of range:\n",
+ i, mcfg->memseg[i].iova);
+ RTE_LOG(INFO, EAL, "\tusing dma mask %"PRIx64"\n", mask);
+
+ return -1;
The control flow looks weird to me. You break if iova has any bits that
are in the mask, then you display log messages and return -1. How about
just logging error and returning -1, and simply returning 0 after the loop?
--
Thanks,
Anatoly
