crypto: omap - add base support library for common routines

This contains the generic APIs for aligning SG buffers.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index fb1e60f5002ef945caa02579cb4e2799a7233e1e..64171cad735d7f18ac40e0949b275f2f60e7ff4f 100644 (file)
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -314,6 +314,15 @@ config HW_RANDOM_PPC4XX
         This option provides the kernel-side support for the TRNG hardware
         found in the security function of some PowerPC 4xx SoCs.
 
+config CRYPTO_DEV_OMAP
+       tristate "Support for OMAP crypto HW accelerators"
+       depends on ARCH_OMAP2PLUS
+       help
+         OMAP processors have various crypto HW accelerators. Select this if
+          you want to use the OMAP modules for any of the crypto algorithms.
+
+if CRYPTO_DEV_OMAP
+
 config CRYPTO_DEV_OMAP_SHAM
        tristate "Support for OMAP MD5/SHA1/SHA2 hw accelerator"
        depends on ARCH_OMAP2PLUS
@@ -351,6 +360,8 @@ config CRYPTO_DEV_OMAP_DES
          the ECB and CBC modes of operation are supported by the driver. Also
          accesses made on unaligned boundaries are supported.
 
+endif # CRYPTO_DEV_OMAP
+
 config CRYPTO_DEV_PICOXCELL
        tristate "Support for picoXcell IPSEC and Layer2 crypto engines"
        depends on (ARCH_PICOXCELL || COMPILE_TEST) && HAVE_CLK

diff --git a/drivers/crypto/Makefile b/drivers/crypto/Makefile
index 463f33592d9391e165e0a44fc1c22370e410bc5c..8fd11510f6b9fe13dcc5e318e7761f9851fd03b6 100644 (file)
--- a/drivers/crypto/Makefile
+++ b/drivers/crypto/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_CRYPTO_DEV_MXC_SCC) += mxc-scc.o
 obj-$(CONFIG_CRYPTO_DEV_NIAGARA2) += n2_crypto.o
 n2_crypto-y := n2_core.o n2_asm.o
 obj-$(CONFIG_CRYPTO_DEV_NX) += nx/
+obj-$(CONFIG_CRYPTO_DEV_OMAP) += omap-crypto.o
 obj-$(CONFIG_CRYPTO_DEV_OMAP_AES) += omap-aes.o
 obj-$(CONFIG_CRYPTO_DEV_OMAP_DES) += omap-des.o
 obj-$(CONFIG_CRYPTO_DEV_OMAP_SHAM) += omap-sham.o

diff --git a/drivers/crypto/omap-crypto.c b/drivers/crypto/omap-crypto.c
new file mode 100644 (file)
index 0000000..23e3777
--- /dev/null
+++ b/drivers/crypto/omap-crypto.c
@@ -0,0 +1,184 @@
+/*
+ * OMAP Crypto driver common support routines.
+ *
+ * Copyright (c) 2017 Texas Instruments Incorporated
+ *   Tero Kristo <t-kristo@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/scatterlist.h>
+#include <crypto/scatterwalk.h>
+
+#include "omap-crypto.h"
+
+static int omap_crypto_copy_sg_lists(int total, int bs,
+                                    struct scatterlist **sg,
+                                    struct scatterlist *new_sg, u16 flags)
+{
+       int n = sg_nents(*sg);
+       struct scatterlist *tmp;
+
+       if (!(flags & OMAP_CRYPTO_FORCE_SINGLE_ENTRY)) {
+               new_sg = kmalloc_array(n, sizeof(*sg), GFP_KERNEL);
+               if (!new_sg)
+                       return -ENOMEM;
+
+               sg_init_table(new_sg, n);
+       }
+
+       tmp = new_sg;
+
+       while (*sg && total) {
+               int len = (*sg)->length;
+
+               if (total < len)
+                       len = total;
+
+               if (len > 0) {
+                       total -= len;
+                       sg_set_page(tmp, sg_page(*sg), len, (*sg)->offset);
+                       if (total <= 0)
+                               sg_mark_end(tmp);
+                       tmp = sg_next(tmp);
+               }
+
+               *sg = sg_next(*sg);
+       }
+
+       *sg = new_sg;
+
+       return 0;
+}
+
+static int omap_crypto_copy_sgs(int total, int bs, struct scatterlist **sg,
+                               struct scatterlist *new_sg, u16 flags)
+{
+       void *buf;
+       int pages;
+       int new_len;
+
+       new_len = ALIGN(total, bs);
+       pages = get_order(new_len);
+
+       buf = (void *)__get_free_pages(GFP_ATOMIC, pages);
+       if (!buf) {
+               pr_err("%s: Couldn't allocate pages for unaligned cases.\n",
+                      __func__);
+               return -ENOMEM;
+       }
+
+       if (flags & OMAP_CRYPTO_COPY_DATA) {
+               scatterwalk_map_and_copy(buf, *sg, 0, total, 0);
+               if (flags & OMAP_CRYPTO_ZERO_BUF)
+                       memset(buf + total, 0, new_len - total);
+       }
+
+       if (!(flags & OMAP_CRYPTO_FORCE_SINGLE_ENTRY))
+               sg_init_table(new_sg, 1);
+
+       sg_set_buf(new_sg, buf, new_len);
+
+       *sg = new_sg;
+
+       return 0;
+}
+
+static int omap_crypto_check_sg(struct scatterlist *sg, int total, int bs,
+                               u16 flags)
+{
+       int len = 0;
+       int num_sg = 0;
+
+       if (!IS_ALIGNED(total, bs))
+               return OMAP_CRYPTO_NOT_ALIGNED;
+
+       while (sg) {
+               num_sg++;
+
+               if (!IS_ALIGNED(sg->offset, 4))
+                       return OMAP_CRYPTO_NOT_ALIGNED;
+               if (!IS_ALIGNED(sg->length, bs))
+                       return OMAP_CRYPTO_NOT_ALIGNED;
+
+               len += sg->length;
+               sg = sg_next(sg);
+
+               if (len >= total)
+                       break;
+       }
+
+       if ((flags & OMAP_CRYPTO_FORCE_SINGLE_ENTRY) && num_sg > 1)
+               return OMAP_CRYPTO_NOT_ALIGNED;
+
+       if (len != total)
+               return OMAP_CRYPTO_BAD_DATA_LENGTH;
+
+       return 0;
+}
+
+int omap_crypto_align_sg(struct scatterlist **sg, int total, int bs,
+                        struct scatterlist *new_sg, u16 flags,
+                        u8 flags_shift, unsigned long *dd_flags)
+{
+       int ret;
+
+       *dd_flags &= ~(OMAP_CRYPTO_COPY_MASK << flags_shift);
+
+       if (flags & OMAP_CRYPTO_FORCE_COPY)
+               ret = OMAP_CRYPTO_NOT_ALIGNED;
+       else
+               ret = omap_crypto_check_sg(*sg, total, bs, flags);
+
+       if (ret == OMAP_CRYPTO_NOT_ALIGNED) {
+               ret = omap_crypto_copy_sgs(total, bs, sg, new_sg, flags);
+               if (ret)
+                       return ret;
+               *dd_flags |= OMAP_CRYPTO_DATA_COPIED << flags_shift;
+       } else if (ret == OMAP_CRYPTO_BAD_DATA_LENGTH) {
+               ret = omap_crypto_copy_sg_lists(total, bs, sg, new_sg, flags);
+               if (ret)
+                       return ret;
+               if (!(flags & OMAP_CRYPTO_FORCE_SINGLE_ENTRY))
+                       *dd_flags |= OMAP_CRYPTO_SG_COPIED << flags_shift;
+       } else if (flags & OMAP_CRYPTO_FORCE_SINGLE_ENTRY) {
+               sg_set_buf(new_sg, sg_virt(*sg), (*sg)->length);
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(omap_crypto_align_sg);
+
+void omap_crypto_cleanup(struct scatterlist *sg, struct scatterlist *orig,
+                        int offset, int len, u8 flags_shift,
+                        unsigned long flags)
+{
+       void *buf;
+       int pages;
+
+       flags >>= flags_shift;
+       flags &= OMAP_CRYPTO_COPY_MASK;
+
+       if (!flags)
+               return;
+
+       buf = sg_virt(sg);
+       pages = get_order(len);
+
+       if (orig && (flags & OMAP_CRYPTO_COPY_MASK))
+               scatterwalk_map_and_copy(buf, orig, offset, len, 1);
+
+       if (flags & OMAP_CRYPTO_DATA_COPIED)
+               free_pages((unsigned long)buf, pages);
+       else if (flags & OMAP_CRYPTO_SG_COPIED)
+               kfree(sg);
+}
+EXPORT_SYMBOL_GPL(omap_crypto_cleanup);
+
+MODULE_DESCRIPTION("OMAP crypto support library.");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Tero Kristo <t-kristo@ti.com>");

diff --git a/drivers/crypto/omap-crypto.h b/drivers/crypto/omap-crypto.h
new file mode 100644 (file)
index 0000000..36a230e
--- /dev/null
+++ b/drivers/crypto/omap-crypto.h
@@ -0,0 +1,37 @@
+/*
+ * OMAP Crypto driver common support routines.
+ *
+ * Copyright (c) 2017 Texas Instruments Incorporated
+ *   Tero Kristo <t-kristo@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#ifndef __CRYPTO_OMAP_CRYPTO_H
+#define __CRYPTO_OMAP_CRYPTO_H
+
+enum {
+       OMAP_CRYPTO_NOT_ALIGNED = 1,
+       OMAP_CRYPTO_BAD_DATA_LENGTH,
+};
+
+#define OMAP_CRYPTO_DATA_COPIED                BIT(0)
+#define OMAP_CRYPTO_SG_COPIED          BIT(1)
+
+#define OMAP_CRYPTO_COPY_MASK          0x3
+
+#define OMAP_CRYPTO_COPY_DATA          BIT(0)
+#define OMAP_CRYPTO_FORCE_COPY         BIT(1)
+#define OMAP_CRYPTO_ZERO_BUF           BIT(2)
+#define OMAP_CRYPTO_FORCE_SINGLE_ENTRY BIT(3)
+
+int omap_crypto_align_sg(struct scatterlist **sg, int total, int bs,
+                        struct scatterlist *new_sg, u16 flags,
+                        u8 flags_shift, unsigned long *dd_flags);
+void omap_crypto_cleanup(struct scatterlist *sg, struct scatterlist *orig,
+                        int offset, int len, u8 flags_shift,
+                        unsigned long flags);
+
+#endif