crypto: nx - make platform drivers directly register with crypto

Remove the common 'platform' registration module, and move the crypto
compression driver registration into each of the pSeries and PowerNV
platform NX 842 drivers.  Change the nx-842.c code into simple common
functions that each platform driver uses to perform constraints-based
buffer changes, i.e. realigning and/or resizing buffers to match the
driver's hardware requirements.

The common 'platform' module was my mistake to create - since each
platform driver will only load/operate when running on its own
platform (i.e. a pSeries platform or a PowerNV platform), they can
directly register with the crypto subsystem, using the same alg and
driver name.  This removes unneeded complexity.

Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

6 files changed, 114 insertions, 191 deletions

diff --git a/drivers/crypto/nx/Makefile b/drivers/crypto/nx/Makefile
index ffcc86c44e15..b727821c8ed4 100644
--- a/drivers/crypto/nx/Makefile
+++ b/drivers/crypto/nx/Makefile
@@ -10,10 +10,8 @@ nx-crypto-objs := nx.o \
                   nx-sha256.o \
                   nx-sha512.o
 
-obj-$(CONFIG_CRYPTO_DEV_NX_COMPRESS) += nx-compress.o nx-compress-platform.o
-obj-$(CONFIG_CRYPTO_DEV_NX_COMPRESS_PSERIES) += nx-compress-pseries.o
-obj-$(CONFIG_CRYPTO_DEV_NX_COMPRESS_POWERNV) += nx-compress-powernv.o
+obj-$(CONFIG_CRYPTO_DEV_NX_COMPRESS_PSERIES) += nx-compress-pseries.o nx-compress.o
+obj-$(CONFIG_CRYPTO_DEV_NX_COMPRESS_POWERNV) += nx-compress-powernv.o nx-compress.o
 nx-compress-objs := nx-842.o
-nx-compress-platform-objs := nx-842-platform.o
 nx-compress-pseries-objs := nx-842-pseries.o
 nx-compress-powernv-objs := nx-842-powernv.o
diff --git a/drivers/crypto/nx/nx-842-platform.c b/drivers/crypto/nx/nx-842-platform.c
deleted file mode 100644
index 664f13dd06ed..000000000000
--- a/drivers/crypto/nx/nx-842-platform.c
+++ /dev/null
@@ -1,84 +0,0 @@
-
-#include "nx-842.h"
-
-/* this is needed, separate from the main nx-842.c driver, because that main
- * driver loads the platform drivers during its init(), and it expects one
- * (or none) of the platform drivers to set this pointer to its driver.
- * That means this pointer can't be in the main nx-842 driver, because it
- * wouldn't be accessible until after the main driver loaded, which wouldn't
- * be possible as it's waiting for the platform driver to load.  So place it
- * here.
- */
-static struct nx842_driver *driver;
-static DEFINE_SPINLOCK(driver_lock);
-
-struct nx842_driver *nx842_platform_driver(void)
-{
-        return driver;
-}
-EXPORT_SYMBOL_GPL(nx842_platform_driver);
-
-bool nx842_platform_driver_set(struct nx842_driver *_driver)
-{
-        bool ret = false;
-
-        spin_lock(&driver_lock);
-
-        if (!driver) {
-                driver = _driver;
-                ret = true;
-        } else
-                WARN(1, "can't set platform driver, already set to %s\n",
-                     driver->name);
-
-        spin_unlock(&driver_lock);
-        return ret;
-}
-EXPORT_SYMBOL_GPL(nx842_platform_driver_set);
-
-/* only call this from the platform driver exit function */
-void nx842_platform_driver_unset(struct nx842_driver *_driver)
-{
-        spin_lock(&driver_lock);
-
-        if (driver == _driver)
-                driver = NULL;
-        else if (driver)
-                WARN(1, "can't unset platform driver %s, currently set to %s\n",
-                     _driver->name, driver->name);
-        else
-                WARN(1, "can't unset platform driver, already unset\n");
-
-        spin_unlock(&driver_lock);
-}
-EXPORT_SYMBOL_GPL(nx842_platform_driver_unset);
-
-bool nx842_platform_driver_get(void)
-{
-        bool ret = false;
-
-        spin_lock(&driver_lock);
-
-        if (driver)
-                ret = try_module_get(driver->owner);
-
-        spin_unlock(&driver_lock);
-
-        return ret;
-}
-EXPORT_SYMBOL_GPL(nx842_platform_driver_get);
-
-void nx842_platform_driver_put(void)
-{
-        spin_lock(&driver_lock);
-
-        if (driver)
-                module_put(driver->owner);
-
-        spin_unlock(&driver_lock);
-}
-EXPORT_SYMBOL_GPL(nx842_platform_driver_put);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");
-MODULE_DESCRIPTION("842 H/W Compression platform driver");
diff --git a/drivers/crypto/nx/nx-842-powernv.c b/drivers/crypto/nx/nx-842-powernv.c
index 7e474562058d..684ce51d2d68 100644
--- a/drivers/crypto/nx/nx-842-powernv.c
+++ b/drivers/crypto/nx/nx-842-powernv.c
@@ -26,6 +26,8 @@
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");
 MODULE_DESCRIPTION("842 H/W Compression driver for IBM PowerNV processors");
+MODULE_ALIAS_CRYPTO("842");
+MODULE_ALIAS_CRYPTO("842-nx");
 
 #define WORKMEM_ALIGN   (CRB_ALIGN)
 #define CSB_WAIT_MAX    (5000) /* ms */
@@ -581,9 +583,29 @@ static struct nx842_driver nx842_powernv_driver = {
         .decompress =   nx842_powernv_decompress,
 };
 
+static int nx842_powernv_crypto_init(struct crypto_tfm *tfm)
+{
+        return nx842_crypto_init(tfm, &nx842_powernv_driver);
+}
+
+static struct crypto_alg nx842_powernv_alg = {
+        .cra_name               = "842",
+        .cra_driver_name        = "842-nx",
+        .cra_priority           = 300,
+        .cra_flags              = CRYPTO_ALG_TYPE_COMPRESS,
+        .cra_ctxsize            = sizeof(struct nx842_crypto_ctx),
+        .cra_module             = THIS_MODULE,
+        .cra_init               = nx842_powernv_crypto_init,
+        .cra_exit               = nx842_crypto_exit,
+        .cra_u                  = { .compress = {
+        .coa_compress           = nx842_crypto_compress,
+        .coa_decompress         = nx842_crypto_decompress } }
+};
+
 static __init int nx842_powernv_init(void)
 {
         struct device_node *dn;
+        int ret;
 
         /* verify workmem size/align restrictions */
         BUILD_BUG_ON(WORKMEM_ALIGN % CRB_ALIGN);
@@ -600,7 +622,8 @@ static __init int nx842_powernv_init(void)
         if (!nx842_ct)
                 return -ENODEV;
 
-        if (!nx842_platform_driver_set(&nx842_powernv_driver)) {
+        ret = crypto_register_alg(&nx842_powernv_alg);
+        if (ret) {
                 struct nx842_coproc *coproc, *n;
 
                 list_for_each_entry_safe(coproc, n, &nx842_coprocs, list) {
@@ -608,7 +631,7 @@ static __init int nx842_powernv_init(void)
                         kfree(coproc);
                 }
 
-                return -EEXIST;
+                return ret;
         }
 
         return 0;
@@ -619,7 +642,7 @@ static void __exit nx842_powernv_exit(void)
 {
         struct nx842_coproc *coproc, *n;
 
-        nx842_platform_driver_unset(&nx842_powernv_driver);
+        crypto_unregister_alg(&nx842_powernv_alg);
 
         list_for_each_entry_safe(coproc, n, &nx842_coprocs, list) {
                 list_del(&coproc->list);
diff --git a/drivers/crypto/nx/nx-842-pseries.c b/drivers/crypto/nx/nx-842-pseries.c
index 4b7bd8fb6a6b..b6a26907e11f 100644
--- a/drivers/crypto/nx/nx-842-pseries.c
+++ b/drivers/crypto/nx/nx-842-pseries.c
@@ -29,6 +29,8 @@
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Robert Jennings <rcj@linux.vnet.ibm.com>");
 MODULE_DESCRIPTION("842 H/W Compression driver for IBM Power processors");
+MODULE_ALIAS_CRYPTO("842");
+MODULE_ALIAS_CRYPTO("842-nx");
 
 static struct nx842_constraints nx842_pseries_constraints = {
         .alignment =    DDE_BUFFER_ALIGN,
@@ -957,6 +959,25 @@ static struct nx842_driver nx842_pseries_driver = {
         .decompress =   nx842_pseries_decompress,
 };
 
+static int nx842_pseries_crypto_init(struct crypto_tfm *tfm)
+{
+        return nx842_crypto_init(tfm, &nx842_pseries_driver);
+}
+
+static struct crypto_alg nx842_pseries_alg = {
+        .cra_name               = "842",
+        .cra_driver_name        = "842-nx",
+        .cra_priority           = 300,
+        .cra_flags              = CRYPTO_ALG_TYPE_COMPRESS,
+        .cra_ctxsize            = sizeof(struct nx842_crypto_ctx),
+        .cra_module             = THIS_MODULE,
+        .cra_init               = nx842_pseries_crypto_init,
+        .cra_exit               = nx842_crypto_exit,
+        .cra_u                  = { .compress = {
+        .coa_compress           = nx842_crypto_compress,
+        .coa_decompress         = nx842_crypto_decompress } }
+};
+
 static int nx842_probe(struct vio_dev *viodev,
                        const struct vio_device_id *id)
 {
@@ -1002,6 +1023,12 @@ static int nx842_probe(struct vio_dev *viodev,
         if (ret)
                 goto error;
 
+        ret = crypto_register_alg(&nx842_pseries_alg);
+        if (ret) {
+                dev_err(&viodev->dev, "could not register comp alg: %d\n", ret);
+                goto error;
+        }
+
         rcu_read_lock();
         dev_set_drvdata(&viodev->dev, rcu_dereference(devdata));
         rcu_read_unlock();
@@ -1031,6 +1058,8 @@ static int nx842_remove(struct vio_dev *viodev)
         pr_info("Removing IBM Power 842 compression device\n");
         sysfs_remove_group(&viodev->dev.kobj, &nx842_attribute_group);
 
+        crypto_unregister_alg(&nx842_pseries_alg);
+
         spin_lock_irqsave(&devdata_mutex, flags);
         old_devdata = rcu_dereference_check(devdata,
                         lockdep_is_held(&devdata_mutex));
@@ -1083,12 +1112,6 @@ static int __init nx842_pseries_init(void)
                 return ret;
         }
 
-        if (!nx842_platform_driver_set(&nx842_pseries_driver)) {
-                vio_unregister_driver(&nx842_vio_driver);
-                kfree(new_devdata);
-                return -EEXIST;
-        }
-
         return 0;
 }
 
@@ -1099,7 +1122,8 @@ static void __exit nx842_pseries_exit(void)
         struct nx842_devdata *old_devdata;
         unsigned long flags;
 
-        nx842_platform_driver_unset(&nx842_pseries_driver);
+        crypto_unregister_alg(&nx842_pseries_alg);
+
         spin_lock_irqsave(&devdata_mutex, flags);
         old_devdata = rcu_dereference_check(devdata,
                         lockdep_is_held(&devdata_mutex));
diff --git a/drivers/crypto/nx/nx-842.c b/drivers/crypto/nx/nx-842.c
index 4472e2001e79..046c1c45411b 100644
--- a/drivers/crypto/nx/nx-842.c
+++ b/drivers/crypto/nx/nx-842.c
@@ -57,12 +57,8 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/crypto.h>
 #include <linux/vmalloc.h>
 #include <linux/sw842.h>
-#include <linux/ratelimit.h>
 #include <linux/spinlock.h>
 
 #include "nx-842.h"
@@ -74,7 +70,6 @@
  * buffer, and passed directly to the hardware to decompress.
  */
 #define NX842_CRYPTO_MAGIC      (0xf842)
-#define NX842_CRYPTO_GROUP_MAX  (0x20)
 #define NX842_CRYPTO_HEADER_SIZE(g)                             \
         (sizeof(struct nx842_crypto_header) +                   \
          sizeof(struct nx842_crypto_header_group) * (g))
@@ -90,19 +85,6 @@
 #define COMP_BUSY_TIMEOUT       (250) /* ms */
 #define DECOMP_BUSY_TIMEOUT     (50) /* ms */
 
-struct nx842_crypto_header_group {
-        __be16 padding;                 /* unused bytes at start of group */
-        __be32 compressed_length;       /* compressed bytes in group */
-        __be32 uncompressed_length;     /* bytes after decompression */
-} __packed;
-
-struct nx842_crypto_header {
-        __be16 magic;           /* NX842_CRYPTO_MAGIC */
-        __be16 ignore;          /* decompressed end bytes to ignore */
-        u8 groups;              /* total groups in this header */
-        struct nx842_crypto_header_group group[];
-} __packed;
-
 struct nx842_crypto_param {
         u8 *in;
         unsigned int iremain;
@@ -128,22 +110,13 @@ static int update_param(struct nx842_crypto_param *p,
         return 0;
 }
 
-struct nx842_crypto_ctx {
-        spinlock_t lock;
-
-        u8 *wmem;
-        u8 *sbounce, *dbounce;
-
-        struct nx842_crypto_header header;
-        struct nx842_crypto_header_group group[NX842_CRYPTO_GROUP_MAX];
-};
-
-static int nx842_crypto_init(struct crypto_tfm *tfm)
+int nx842_crypto_init(struct crypto_tfm *tfm, struct nx842_driver *driver)
 {
         struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm);
 
         spin_lock_init(&ctx->lock);
-        ctx->wmem = kmalloc(nx842_workmem_size(), GFP_KERNEL);
+        ctx->driver = driver;
+        ctx->wmem = kmalloc(driver->workmem_size, GFP_KERNEL);
         ctx->sbounce = (u8 *)__get_free_pages(GFP_KERNEL, BOUNCE_BUFFER_ORDER);
         ctx->dbounce = (u8 *)__get_free_pages(GFP_KERNEL, BOUNCE_BUFFER_ORDER);
         if (!ctx->wmem || !ctx->sbounce || !ctx->dbounce) {
@@ -155,8 +128,9 @@ static int nx842_crypto_init(struct crypto_tfm *tfm)
 
         return 0;
 }
+EXPORT_SYMBOL_GPL(nx842_crypto_init);
 
-static void nx842_crypto_exit(struct crypto_tfm *tfm)
+void nx842_crypto_exit(struct crypto_tfm *tfm)
 {
         struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm);
 
@@ -164,6 +138,7 @@ static void nx842_crypto_exit(struct crypto_tfm *tfm)
         free_page((unsigned long)ctx->sbounce);
         free_page((unsigned long)ctx->dbounce);
 }
+EXPORT_SYMBOL_GPL(nx842_crypto_exit);
 
 static void check_constraints(struct nx842_constraints *c)
 {
@@ -250,9 +225,7 @@ nospc:
         timeout = ktime_add_ms(ktime_get(), COMP_BUSY_TIMEOUT);
         do {
                 dlen = tmplen; /* reset dlen, if we're retrying */
-                ret = nx842_platform_driver()->compress(src, slen,
-                                                        dst, &dlen,
-                                                        ctx->wmem);
+                ret = ctx->driver->compress(src, slen, dst, &dlen, ctx->wmem);
                 /* possibly we should reduce the slen here, instead of
                  * retrying with the dbounce buffer?
                  */
@@ -282,14 +255,14 @@ nospc:
         return update_param(p, slen, dskip + dlen);
 }
 
-static int nx842_crypto_compress(struct crypto_tfm *tfm,
-                                 const u8 *src, unsigned int slen,
-                                 u8 *dst, unsigned int *dlen)
+int nx842_crypto_compress(struct crypto_tfm *tfm,
+                          const u8 *src, unsigned int slen,
+                          u8 *dst, unsigned int *dlen)
 {
         struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm);
         struct nx842_crypto_header *hdr = &ctx->header;
         struct nx842_crypto_param p;
-        struct nx842_constraints c = *nx842_platform_driver()->constraints;
+        struct nx842_constraints c = *ctx->driver->constraints;
         unsigned int groups, hdrsize, h;
         int ret, n;
         bool add_header;
@@ -366,6 +339,7 @@ unlock:
         spin_unlock_bh(&ctx->lock);
         return ret;
 }
+EXPORT_SYMBOL_GPL(nx842_crypto_compress);
 
 static int decompress(struct nx842_crypto_ctx *ctx,
                       struct nx842_crypto_param *p,
@@ -429,9 +403,7 @@ static int decompress(struct nx842_crypto_ctx *ctx,
         timeout = ktime_add_ms(ktime_get(), DECOMP_BUSY_TIMEOUT);
         do {
                 dlen = tmplen; /* reset dlen, if we're retrying */
-                ret = nx842_platform_driver()->decompress(src, slen,
-                                                          dst, &dlen,
-                                                          ctx->wmem);
+                ret = ctx->driver->decompress(src, slen, dst, &dlen, ctx->wmem);
         } while (ret == -EBUSY && ktime_before(ktime_get(), timeout));
         if (ret) {
 usesw:
@@ -467,14 +439,14 @@ usesw:
         return update_param(p, slen + padding, dlen);
 }
 
-static int nx842_crypto_decompress(struct crypto_tfm *tfm,
-                                   const u8 *src, unsigned int slen,
-                                   u8 *dst, unsigned int *dlen)
+int nx842_crypto_decompress(struct crypto_tfm *tfm,
+                            const u8 *src, unsigned int slen,
+                            u8 *dst, unsigned int *dlen)
 {
         struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm);
         struct nx842_crypto_header *hdr;
         struct nx842_crypto_param p;
-        struct nx842_constraints c = *nx842_platform_driver()->constraints;
+        struct nx842_constraints c = *ctx->driver->constraints;
         int n, ret, hdr_len;
         u16 ignore = 0;
 
@@ -552,49 +524,8 @@ unlock:
 
         return ret;
 }
-
-static struct crypto_alg alg = {
-        .cra_name               = "842",
-        .cra_driver_name        = "842-nx",
-        .cra_priority           = 300,
-        .cra_flags              = CRYPTO_ALG_TYPE_COMPRESS,
-        .cra_ctxsize            = sizeof(struct nx842_crypto_ctx),
-        .cra_module             = THIS_MODULE,
-        .cra_init               = nx842_crypto_init,
-        .cra_exit               = nx842_crypto_exit,
-        .cra_u                  = { .compress = {
-        .coa_compress           = nx842_crypto_compress,
-        .coa_decompress         = nx842_crypto_decompress } }
-};
-
-static int __init nx842_crypto_mod_init(void)
-{
-        request_module("nx-compress-powernv");
-        request_module("nx-compress-pseries");
-
-        /* we prevent loading/registering if there's no platform driver,
-         * and we get the platform module that set it so it won't unload,
-         * so we don't need to check if it's set in any of our functions
-         */
-        if (!nx842_platform_driver_get()) {
-                pr_err("no nx842 platform driver found.\n");
-                return -ENODEV;
-        }
-
-        return crypto_register_alg(&alg);
-}
-module_init(nx842_crypto_mod_init);
-
-static void __exit nx842_crypto_mod_exit(void)
-{
-        crypto_unregister_alg(&alg);
-
-        nx842_platform_driver_put();
-}
-module_exit(nx842_crypto_mod_exit);
+EXPORT_SYMBOL_GPL(nx842_crypto_decompress);
 
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("IBM PowerPC Nest (NX) 842 Hardware Compression Driver");
-MODULE_ALIAS_CRYPTO("842");
-MODULE_ALIAS_CRYPTO("842-nx");
 MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");
diff --git a/drivers/crypto/nx/nx-842.h b/drivers/crypto/nx/nx-842.h
index c7dd0a4391e0..a4eee3bba937 100644
--- a/drivers/crypto/nx/nx-842.h
+++ b/drivers/crypto/nx/nx-842.h
@@ -3,8 +3,9 @@
 #define __NX_842_H__
 
 #include <linux/kernel.h>
+#include <linux/init.h>
 #include <linux/module.h>
-#include <linux/sw842.h>
+#include <linux/crypto.h>
 #include <linux/of.h>
 #include <linux/slab.h>
 #include <linux/io.h>
@@ -145,10 +146,40 @@ struct nx842_driver {
                           void *wrkmem);
 };
 
-struct nx842_driver *nx842_platform_driver(void);
-bool nx842_platform_driver_set(struct nx842_driver *driver);
-void nx842_platform_driver_unset(struct nx842_driver *driver);
-bool nx842_platform_driver_get(void);
-void nx842_platform_driver_put(void);
+struct nx842_crypto_header_group {
+        __be16 padding;                 /* unused bytes at start of group */
+        __be32 compressed_length;       /* compressed bytes in group */
+        __be32 uncompressed_length;     /* bytes after decompression */
+} __packed;
+
+struct nx842_crypto_header {
+        __be16 magic;           /* NX842_CRYPTO_MAGIC */
+        __be16 ignore;          /* decompressed end bytes to ignore */
+        u8 groups;              /* total groups in this header */
+        struct nx842_crypto_header_group group[];
+} __packed;
+
+#define NX842_CRYPTO_GROUP_MAX  (0x20)
+
+struct nx842_crypto_ctx {
+        spinlock_t lock;
+
+        u8 *wmem;
+        u8 *sbounce, *dbounce;
+
+        struct nx842_crypto_header header;
+        struct nx842_crypto_header_group group[NX842_CRYPTO_GROUP_MAX];
+
+        struct nx842_driver *driver;
+};
+
+int nx842_crypto_init(struct crypto_tfm *tfm, struct nx842_driver *driver);
+void nx842_crypto_exit(struct crypto_tfm *tfm);
+int nx842_crypto_compress(struct crypto_tfm *tfm,
+                          const u8 *src, unsigned int slen,
+                          u8 *dst, unsigned int *dlen);
+int nx842_crypto_decompress(struct crypto_tfm *tfm,
+                            const u8 *src, unsigned int slen,
+                            u8 *dst, unsigned int *dlen);
 
 #endif /* __NX_842_H__ */