- int ret;
- struct blkcipher_walk walk;
- struct p8_aes_ctr_ctx *ctx = crypto_tfm_ctx(
- crypto_blkcipher_tfm(desc->tfm));
- struct blkcipher_desc fallback_desc = {
- .tfm = ctx->fallback,
- .info = desc->info,
- .flags = desc->flags
- };
-
- if (in_interrupt()) {
- ret = crypto_blkcipher_encrypt(&fallback_desc, dst, src, nbytes);
- } else {
- blkcipher_walk_init(&walk, dst, src, nbytes);
- ret = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE);
- while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
- pagefault_disable();
- enable_kernel_altivec();
- enable_kernel_vsx();
- aes_p8_ctr32_encrypt_blocks(walk.src.virt.addr, walk.dst.virt.addr,
- (nbytes & AES_BLOCK_MASK)/AES_BLOCK_SIZE, &ctx->enc_key, walk.iv);
- pagefault_enable();
-
- crypto_inc(walk.iv, AES_BLOCK_SIZE);
- nbytes &= AES_BLOCK_SIZE - 1;
- ret = blkcipher_walk_done(desc, &walk, nbytes);
- }
- if (walk.nbytes) {
- p8_aes_ctr_final(ctx, &walk);
- ret = blkcipher_walk_done(desc, &walk, 0);
- }
- }
-
- return ret;
+ int ret;
+ u64 inc;
+ struct blkcipher_walk walk;
+ struct p8_aes_ctr_ctx *ctx =
+ crypto_tfm_ctx(crypto_blkcipher_tfm(desc->tfm));
+ struct blkcipher_desc fallback_desc = {
+ .tfm = ctx->fallback,
+ .info = desc->info,
+ .flags = desc->flags
+ };
+
+ if (in_interrupt()) {
+ ret = crypto_blkcipher_encrypt(&fallback_desc, dst, src,
+ nbytes);
+ } else {
+ blkcipher_walk_init(&walk, dst, src, nbytes);
+ ret = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE);
+ while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
+ pagefault_disable();
+ enable_kernel_altivec();
+ enable_kernel_vsx();
+ aes_p8_ctr32_encrypt_blocks(walk.src.virt.addr,
+ walk.dst.virt.addr,
+ (nbytes &
+ AES_BLOCK_MASK) /
+ AES_BLOCK_SIZE,
+ &ctx->enc_key,
+ walk.iv);
+ pagefault_enable();
+
+ /* We need to update IV mostly for last bytes/round */
+ inc = (nbytes & AES_BLOCK_MASK) / AES_BLOCK_SIZE;
+ if (inc > 0)
+ while (inc--)
+ crypto_inc(walk.iv, AES_BLOCK_SIZE);
+
+ nbytes &= AES_BLOCK_SIZE - 1;
+ ret = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+ if (walk.nbytes) {
+ p8_aes_ctr_final(ctx, &walk);
+ ret = blkcipher_walk_done(desc, &walk, 0);
+ }
+ }
+
+ return ret;