+
+int
+nfsd4_scsi_decode_layoutupdate(__be32 *p, u32 len, struct iomap **iomapp,
+ u32 block_size)
+{
+ struct iomap *iomaps;
+ u32 nr_iomaps, expected, i;
+
+ if (len < sizeof(u32)) {
+ dprintk("%s: extent array too small: %u\n", __func__, len);
+ return -EINVAL;
+ }
+
+ nr_iomaps = be32_to_cpup(p++);
+ expected = sizeof(__be32) + nr_iomaps * PNFS_SCSI_RANGE_SIZE;
+ if (len != expected) {
+ dprintk("%s: extent array size mismatch: %u/%u\n",
+ __func__, len, expected);
+ return -EINVAL;
+ }
+
+ iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
+ if (!iomaps) {
+ dprintk("%s: failed to allocate extent array\n", __func__);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < nr_iomaps; i++) {
+ u64 val;
+
+ p = xdr_decode_hyper(p, &val);
+ if (val & (block_size - 1)) {
+ dprintk("%s: unaligned offset 0x%llx\n", __func__, val);
+ goto fail;
+ }
+ iomaps[i].offset = val;
+
+ p = xdr_decode_hyper(p, &val);
+ if (val & (block_size - 1)) {
+ dprintk("%s: unaligned length 0x%llx\n", __func__, val);
+ goto fail;
+ }
+ iomaps[i].length = val;
+ }
+
+ *iomapp = iomaps;
+ return nr_iomaps;
+fail:
+ kfree(iomaps);
+ return -EINVAL;
+}