Merge branch 'master' of /home/davem/src/GIT/linux-2.6/

Conflicts:
	drivers/net/wimax/i2400m/usb-notif.c

13 files changed, 149 insertions, 126 deletions

diff --git a/arch/s390/crypto/sha.h b/arch/s390/crypto/sha.h
index 1ceafa571ea..f4e9dc71675 100644
--- a/arch/s390/crypto/sha.h
+++ b/arch/s390/crypto/sha.h
@@ -29,7 +29,9 @@ struct s390_sha_ctx {
 	int func;		/* KIMD function to use */
 };
 
-void s390_sha_update(struct crypto_tfm *tfm, const u8 *data, unsigned int len);
-void s390_sha_final(struct crypto_tfm *tfm, u8 *out);
+struct shash_desc;
+
+int s390_sha_update(struct shash_desc *desc, const u8 *data, unsigned int len);
+int s390_sha_final(struct shash_desc *desc, u8 *out);
 
 #endif
diff --git a/arch/s390/crypto/sha1_s390.c b/arch/s390/crypto/sha1_s390.c
index b3cb5a89b00..e85ba348722 100644
--- a/arch/s390/crypto/sha1_s390.c
+++ b/arch/s390/crypto/sha1_s390.c
@@ -23,17 +23,17 @@
  * any later version.
  *
  */
+#include <crypto/internal/hash.h>
 #include <linux/init.h>
 #include <linux/module.h>
-#include <linux/crypto.h>
 #include <crypto/sha.h>
 
 #include "crypt_s390.h"
 #include "sha.h"
 
-static void sha1_init(struct crypto_tfm *tfm)
+static int sha1_init(struct shash_desc *desc)
 {
-	struct s390_sha_ctx *sctx = crypto_tfm_ctx(tfm);
+	struct s390_sha_ctx *sctx = shash_desc_ctx(desc);
 
 	sctx->state[0] = SHA1_H0;
 	sctx->state[1] = SHA1_H1;
@@ -42,34 +42,36 @@ static void sha1_init(struct crypto_tfm *tfm)
 	sctx->state[4] = SHA1_H4;
 	sctx->count = 0;
 	sctx->func = KIMD_SHA_1;
+
+	return 0;
 }
 
-static struct crypto_alg alg = {
-	.cra_name	=	"sha1",
-	.cra_driver_name=	"sha1-s390",
-	.cra_priority	=	CRYPT_S390_PRIORITY,
-	.cra_flags	=	CRYPTO_ALG_TYPE_DIGEST,
-	.cra_blocksize	=	SHA1_BLOCK_SIZE,
-	.cra_ctxsize	=	sizeof(struct s390_sha_ctx),
-	.cra_module	=	THIS_MODULE,
-	.cra_list	=	LIST_HEAD_INIT(alg.cra_list),
-	.cra_u		=	{ .digest = {
-	.dia_digestsize	=	SHA1_DIGEST_SIZE,
-	.dia_init	=	sha1_init,
-	.dia_update	=	s390_sha_update,
-	.dia_final	=	s390_sha_final } }
+static struct shash_alg alg = {
+	.digestsize	=	SHA1_DIGEST_SIZE,
+	.init		=	sha1_init,
+	.update		=	s390_sha_update,
+	.final		=	s390_sha_final,
+	.descsize	=	sizeof(struct s390_sha_ctx),
+	.base		=	{
+		.cra_name	=	"sha1",
+		.cra_driver_name=	"sha1-s390",
+		.cra_priority	=	CRYPT_S390_PRIORITY,
+		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
+		.cra_blocksize	=	SHA1_BLOCK_SIZE,
+		.cra_module	=	THIS_MODULE,
+	}
 };
 
 static int __init sha1_s390_init(void)
 {
 	if (!crypt_s390_func_available(KIMD_SHA_1))
 		return -EOPNOTSUPP;
-	return crypto_register_alg(&alg);
+	return crypto_register_shash(&alg);
 }
 
 static void __exit sha1_s390_fini(void)
 {
-	crypto_unregister_alg(&alg);
+	crypto_unregister_shash(&alg);
 }
 
 module_init(sha1_s390_init);
diff --git a/arch/s390/crypto/sha256_s390.c b/arch/s390/crypto/sha256_s390.c
index 19c03fb6ba7..f9fefc56963 100644
--- a/arch/s390/crypto/sha256_s390.c
+++ b/arch/s390/crypto/sha256_s390.c
@@ -16,17 +16,17 @@
  * any later version.
  *
  */
+#include <crypto/internal/hash.h>
 #include <linux/init.h>
 #include <linux/module.h>
-#include <linux/crypto.h>
 #include <crypto/sha.h>
 
 #include "crypt_s390.h"
 #include "sha.h"
 
-static void sha256_init(struct crypto_tfm *tfm)
+static int sha256_init(struct shash_desc *desc)
 {
-	struct s390_sha_ctx *sctx = crypto_tfm_ctx(tfm);
+	struct s390_sha_ctx *sctx = shash_desc_ctx(desc);
 
 	sctx->state[0] = SHA256_H0;
 	sctx->state[1] = SHA256_H1;
@@ -38,22 +38,24 @@ static void sha256_init(struct crypto_tfm *tfm)
 	sctx->state[7] = SHA256_H7;
 	sctx->count = 0;
 	sctx->func = KIMD_SHA_256;
+
+	return 0;
 }
 
-static struct crypto_alg alg = {
-	.cra_name	=	"sha256",
-	.cra_driver_name =	"sha256-s390",
-	.cra_priority	=	CRYPT_S390_PRIORITY,
-	.cra_flags	=	CRYPTO_ALG_TYPE_DIGEST,
-	.cra_blocksize	=	SHA256_BLOCK_SIZE,
-	.cra_ctxsize	=	sizeof(struct s390_sha_ctx),
-	.cra_module	=	THIS_MODULE,
-	.cra_list	=	LIST_HEAD_INIT(alg.cra_list),
-	.cra_u		=	{ .digest = {
-	.dia_digestsize	=	SHA256_DIGEST_SIZE,
-	.dia_init	=	sha256_init,
-	.dia_update	=	s390_sha_update,
-	.dia_final	=	s390_sha_final } }
+static struct shash_alg alg = {
+	.digestsize	=	SHA256_DIGEST_SIZE,
+	.init		=	sha256_init,
+	.update		=	s390_sha_update,
+	.final		=	s390_sha_final,
+	.descsize	=	sizeof(struct s390_sha_ctx),
+	.base		=	{
+		.cra_name	=	"sha256",
+		.cra_driver_name=	"sha256-s390",
+		.cra_priority	=	CRYPT_S390_PRIORITY,
+		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
+		.cra_blocksize	=	SHA256_BLOCK_SIZE,
+		.cra_module	=	THIS_MODULE,
+	}
 };
 
 static int sha256_s390_init(void)
@@ -61,12 +63,12 @@ static int sha256_s390_init(void)
 	if (!crypt_s390_func_available(KIMD_SHA_256))
 		return -EOPNOTSUPP;
 
-	return crypto_register_alg(&alg);
+	return crypto_register_shash(&alg);
 }
 
 static void __exit sha256_s390_fini(void)
 {
-	crypto_unregister_alg(&alg);
+	crypto_unregister_shash(&alg);
 }
 
 module_init(sha256_s390_init);
diff --git a/arch/s390/crypto/sha512_s390.c b/arch/s390/crypto/sha512_s390.c
index 23c7861f6ae..83192bfc804 100644
--- a/arch/s390/crypto/sha512_s390.c
+++ b/arch/s390/crypto/sha512_s390.c
@@ -12,16 +12,16 @@
  * any later version.
  *
  */
+#include <crypto/internal/hash.h>
 #include <linux/init.h>
 #include <linux/module.h>
-#include <linux/crypto.h>
 
 #include "sha.h"
 #include "crypt_s390.h"
 
-static void sha512_init(struct crypto_tfm *tfm)
+static int sha512_init(struct shash_desc *desc)
 {
-	struct s390_sha_ctx *ctx = crypto_tfm_ctx(tfm);
+	struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
 
 	*(__u64 *)&ctx->state[0] = 0x6a09e667f3bcc908ULL;
 	*(__u64 *)&ctx->state[2] = 0xbb67ae8584caa73bULL;
@@ -33,29 +33,31 @@ static void sha512_init(struct crypto_tfm *tfm)
 	*(__u64 *)&ctx->state[14] = 0x5be0cd19137e2179ULL;
 	ctx->count = 0;
 	ctx->func = KIMD_SHA_512;
+
+	return 0;
 }
 
-static struct crypto_alg sha512_alg = {
-	.cra_name	=	"sha512",
-	.cra_driver_name =	"sha512-s390",
-	.cra_priority	=	CRYPT_S390_PRIORITY,
-	.cra_flags	=	CRYPTO_ALG_TYPE_DIGEST,
-	.cra_blocksize	=	SHA512_BLOCK_SIZE,
-	.cra_ctxsize	=	sizeof(struct s390_sha_ctx),
-	.cra_module	=	THIS_MODULE,
-	.cra_list	=	LIST_HEAD_INIT(sha512_alg.cra_list),
-	.cra_u		=	{ .digest = {
-	.dia_digestsize	=	SHA512_DIGEST_SIZE,
-	.dia_init	=	sha512_init,
-	.dia_update	=	s390_sha_update,
-	.dia_final	=	s390_sha_final } }
+static struct shash_alg sha512_alg = {
+	.digestsize	=	SHA512_DIGEST_SIZE,
+	.init		=	sha512_init,
+	.update		=	s390_sha_update,
+	.final		=	s390_sha_final,
+	.descsize	=	sizeof(struct s390_sha_ctx),
+	.base		=	{
+		.cra_name	=	"sha512",
+		.cra_driver_name=	"sha512-s390",
+		.cra_priority	=	CRYPT_S390_PRIORITY,
+		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
+		.cra_blocksize	=	SHA512_BLOCK_SIZE,
+		.cra_module	=	THIS_MODULE,
+	}
 };
 
 MODULE_ALIAS("sha512");
 
-static void sha384_init(struct crypto_tfm *tfm)
+static int sha384_init(struct shash_desc *desc)
 {
-	struct s390_sha_ctx *ctx = crypto_tfm_ctx(tfm);
+	struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
 
 	*(__u64 *)&ctx->state[0] = 0xcbbb9d5dc1059ed8ULL;
 	*(__u64 *)&ctx->state[2] = 0x629a292a367cd507ULL;
@@ -67,22 +69,25 @@ static void sha384_init(struct crypto_tfm *tfm)
 	*(__u64 *)&ctx->state[14] = 0x47b5481dbefa4fa4ULL;
 	ctx->count = 0;
 	ctx->func = KIMD_SHA_512;
+
+	return 0;
 }
 
-static struct crypto_alg sha384_alg = {
-	.cra_name	=	"sha384",
-	.cra_driver_name =	"sha384-s390",
-	.cra_priority	=	CRYPT_S390_PRIORITY,
-	.cra_flags	=	CRYPTO_ALG_TYPE_DIGEST,
-	.cra_blocksize	=	SHA384_BLOCK_SIZE,
-	.cra_ctxsize	=	sizeof(struct s390_sha_ctx),
-	.cra_module	=	THIS_MODULE,
-	.cra_list	=	LIST_HEAD_INIT(sha384_alg.cra_list),
-	.cra_u		=	{ .digest = {
-	.dia_digestsize	=	SHA384_DIGEST_SIZE,
-	.dia_init	=	sha384_init,
-	.dia_update	=	s390_sha_update,
-	.dia_final	=	s390_sha_final } }
+static struct shash_alg sha384_alg = {
+	.digestsize	=	SHA384_DIGEST_SIZE,
+	.init		=	sha384_init,
+	.update		=	s390_sha_update,
+	.final		=	s390_sha_final,
+	.descsize	=	sizeof(struct s390_sha_ctx),
+	.base		=	{
+		.cra_name	=	"sha384",
+		.cra_driver_name=	"sha384-s390",
+		.cra_priority	=	CRYPT_S390_PRIORITY,
+		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
+		.cra_blocksize	=	SHA384_BLOCK_SIZE,
+		.cra_ctxsize	=	sizeof(struct s390_sha_ctx),
+		.cra_module	=	THIS_MODULE,
+	}
 };
 
 MODULE_ALIAS("sha384");
@@ -93,18 +98,18 @@ static int __init init(void)
 
 	if (!crypt_s390_func_available(KIMD_SHA_512))
 		return -EOPNOTSUPP;
-	if ((ret = crypto_register_alg(&sha512_alg)) < 0)
+	if ((ret = crypto_register_shash(&sha512_alg)) < 0)
 		goto out;
-	if ((ret = crypto_register_alg(&sha384_alg)) < 0)
-		crypto_unregister_alg(&sha512_alg);
+	if ((ret = crypto_register_shash(&sha384_alg)) < 0)
+		crypto_unregister_shash(&sha512_alg);
 out:
 	return ret;
 }
 
 static void __exit fini(void)
 {
-	crypto_unregister_alg(&sha512_alg);
-	crypto_unregister_alg(&sha384_alg);
+	crypto_unregister_shash(&sha512_alg);
+	crypto_unregister_shash(&sha384_alg);
 }
 
 module_init(init);
diff --git a/arch/s390/crypto/sha_common.c b/arch/s390/crypto/sha_common.c
index 9d6eb8c3d37..7903ec47e6b 100644
--- a/arch/s390/crypto/sha_common.c
+++ b/arch/s390/crypto/sha_common.c
@@ -13,14 +13,14 @@
  *
  */
 
-#include <linux/crypto.h>
+#include <crypto/internal/hash.h>
 #include "sha.h"
 #include "crypt_s390.h"
 
-void s390_sha_update(struct crypto_tfm *tfm, const u8 *data, unsigned int len)
+int s390_sha_update(struct shash_desc *desc, const u8 *data, unsigned int len)
 {
-	struct s390_sha_ctx *ctx = crypto_tfm_ctx(tfm);
-	unsigned int bsize = crypto_tfm_alg_blocksize(tfm);
+	struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
+	unsigned int bsize = crypto_shash_blocksize(desc->tfm);
 	unsigned int index;
 	int ret;
 
@@ -51,13 +51,15 @@ void s390_sha_update(struct crypto_tfm *tfm, const u8 *data, unsigned int len)
 store:
 	if (len)
 		memcpy(ctx->buf + index , data, len);
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(s390_sha_update);
 
-void s390_sha_final(struct crypto_tfm *tfm, u8 *out)
+int s390_sha_final(struct shash_desc *desc, u8 *out)
 {
-	struct s390_sha_ctx *ctx = crypto_tfm_ctx(tfm);
-	unsigned int bsize = crypto_tfm_alg_blocksize(tfm);
+	struct s390_sha_ctx *ctx = shash_desc_ctx(desc);
+	unsigned int bsize = crypto_shash_blocksize(desc->tfm);
 	u64 bits;
 	unsigned int index, end, plen;
 	int ret;
@@ -87,9 +89,11 @@ void s390_sha_final(struct crypto_tfm *tfm, u8 *out)
 	BUG_ON(ret != end);
 
 	/* copy digest to out */
-	memcpy(out, ctx->state, crypto_hash_digestsize(crypto_hash_cast(tfm)));
+	memcpy(out, ctx->state, crypto_shash_digestsize(desc->tfm));
 	/* wipe context */
 	memset(ctx, 0, sizeof *ctx);
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(s390_sha_final);
 
diff --git a/arch/s390/include/asm/mman.h b/arch/s390/include/asm/mman.h
index 7839767d837..da01432e8f4 100644
--- a/arch/s390/include/asm/mman.h
+++ b/arch/s390/include/asm/mman.h
@@ -22,4 +22,9 @@
 #define MCL_CURRENT	1		/* lock all current mappings */
 #define MCL_FUTURE	2		/* lock all future mappings */
 
+#if defined(__KERNEL__) && !defined(__ASSEMBLY__) && defined(CONFIG_64BIT)
+int s390_mmap_check(unsigned long addr, unsigned long len);
+#define arch_mmap_check(addr,len,flags)	s390_mmap_check(addr,len)
+#endif
+
 #endif /* __S390_MMAN_H__ */
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index 066b99502e0..db4523fe38a 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -61,7 +61,7 @@ extern void print_cpu_info(struct cpuinfo_S390 *);
 extern int get_cpu_capability(unsigned int *);
 
 /*
- * User space process size: 2GB for 31 bit, 4TB for 64 bit.
+ * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
  */
 #ifndef __s390x__
 
@@ -70,8 +70,7 @@ extern int get_cpu_capability(unsigned int *);
 
 #else /* __s390x__ */
 
-#define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk,TIF_31BIT) ? \
-					(1UL << 31) : (1UL << 53))
+#define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
 					(1UL << 30) : (1UL << 41))
 #define TASK_SIZE		TASK_SIZE_OF(current)
diff --git a/arch/s390/include/asm/topology.h b/arch/s390/include/asm/topology.h
index c93eb50e1d0..c979c3b56ab 100644
--- a/arch/s390/include/asm/topology.h
+++ b/arch/s390/include/asm/topology.h
@@ -30,6 +30,8 @@ static inline void s390_init_cpu_topology(void)
 };
 #endif
 
+#define SD_MC_INIT SD_CPU_INIT
+
 #include <asm-generic/topology.h>
 
 #endif /* _ASM_S390_TOPOLOGY_H */
diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S
index 397d131a345..80641224a09 100644
--- a/arch/s390/kernel/mcount.S
+++ b/arch/s390/kernel/mcount.S
@@ -5,6 +5,8 @@
  *
  */
 
+#include <asm/asm-offsets.h>
+
 #ifndef CONFIG_64BIT
 .globl _mcount
 _mcount:
@@ -14,7 +16,7 @@ _mcount:
 	ahi	%r15,-96
 	l	%r3,100(%r15)
 	la	%r2,0(%r14)
-	st	%r1,0(%r15)
+	st	%r1,__SF_BACKCHAIN(%r15)
 	la	%r3,0(%r3)
 	bras	%r14,0f
 	.long	ftrace_trace_function
@@ -38,7 +40,7 @@ _mcount:
 	stg	%r14,112(%r15)
 	lgr	%r1,%r15
 	aghi	%r15,-160
-	stg	%r1,0(%r15)
+	stg	%r1,__SF_BACKCHAIN(%r15)
 	lgr	%r2,%r14
 	lg	%r3,168(%r15)
 	larl	%r14,ftrace_trace_function
diff --git a/arch/s390/lib/div64.c b/arch/s390/lib/div64.c
index a5f8300bf3e..d9e62c0b576 100644
--- a/arch/s390/lib/div64.c
+++ b/arch/s390/lib/div64.c
@@ -61,7 +61,7 @@ static uint32_t __div64_31(uint64_t *n, uint32_t base)
 		"	clr	%0,%3\n"
 		"	jl	0f\n"
 		"	slr	%0,%3\n"
-		"	alr	%1,%2\n"
+		"	ahi	%1,1\n"
 		"0:\n"
 		: "+d" (reg2), "+d" (reg3), "=d" (tmp)
 		: "d" (base), "2" (1UL) : "cc" );
diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c
index d66215b0fde..b0b84c35b0a 100644
--- a/arch/s390/lib/uaccess_pt.c
+++ b/arch/s390/lib/uaccess_pt.c
@@ -119,8 +119,6 @@ retry:
 			goto fault;
 
 		pfn = pte_pfn(*pte);
-		if (!pfn_valid(pfn))
-			goto out;
 
 		offset = uaddr & (PAGE_SIZE - 1);
 		size = min(n - done, PAGE_SIZE - offset);
@@ -135,7 +133,6 @@ retry:
 		done += size;
 		uaddr += size;
 	} while (done < n);
-out:
 	spin_unlock(&mm->page_table_lock);
 	return n - done;
 fault:
@@ -163,9 +160,6 @@ retry:
 		goto fault;
 
 	pfn = pte_pfn(*pte);
-	if (!pfn_valid(pfn))
-		goto out;
-
 	ret = (pfn << PAGE_SHIFT) + (uaddr & (PAGE_SIZE - 1));
 out:
 	return ret;
@@ -244,11 +238,6 @@ retry:
 			goto fault;
 
 		pfn = pte_pfn(*pte);
-		if (!pfn_valid(pfn)) {
-			done = -1;
-			goto out;
-		}
-
 		offset = uaddr & (PAGE_SIZE-1);
 		addr = (char *)(pfn << PAGE_SHIFT) + offset;
 		len = min(count - done, PAGE_SIZE - offset);
@@ -256,7 +245,6 @@ retry:
 		done += len_str;
 		uaddr += len_str;
 	} while ((len_str == len) && (done < count));
-out:
 	spin_unlock(&mm->page_table_lock);
 	return done + 1;
 fault:
@@ -325,12 +313,7 @@ retry:
 		}
 
 		pfn_from = pte_pfn(*pte_from);
-		if (!pfn_valid(pfn_from))
-			goto out;
 		pfn_to = pte_pfn(*pte_to);
-		if (!pfn_valid(pfn_to))
-			goto out;
-
 		offset_from = uaddr_from & (PAGE_SIZE-1);
 		offset_to = uaddr_from & (PAGE_SIZE-1);
 		offset_max = max(offset_from, offset_to);
@@ -342,7 +325,6 @@ retry:
 		uaddr_from += size;
 		uaddr_to += size;
 	} while (done < n);
-out:
 	spin_unlock(&mm->page_table_lock);
 	return n - done;
 fault:
diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
index 5932a824547..e008d236cc1 100644
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -35,7 +35,7 @@
  * Leave an at least ~128 MB hole.
  */
 #define MIN_GAP (128*1024*1024)
-#define MAX_GAP (TASK_SIZE/6*5)
+#define MAX_GAP (STACK_TOP/6*5)
 
 static inline unsigned long mmap_base(void)
 {
@@ -46,7 +46,7 @@ static inline unsigned long mmap_base(void)
 	else if (gap > MAX_GAP)
 		gap = MAX_GAP;
 
-	return TASK_SIZE - (gap & PAGE_MASK);
+	return STACK_TOP - (gap & PAGE_MASK);
 }
 
 static inline int mmap_is_legacy(void)
@@ -89,42 +89,58 @@ EXPORT_SYMBOL_GPL(arch_pick_mmap_layout);
 
 #else
 
+int s390_mmap_check(unsigned long addr, unsigned long len)
+{
+	if (!test_thread_flag(TIF_31BIT) &&
+	    len >= TASK_SIZE && TASK_SIZE < (1UL << 53))
+		return crst_table_upgrade(current->mm, 1UL << 53);
+	return 0;
+}
+
 static unsigned long
 s390_get_unmapped_area(struct file *filp, unsigned long addr,
 		unsigned long len, unsigned long pgoff, unsigned long flags)
 {
 	struct mm_struct *mm = current->mm;
+	unsigned long area;
 	int rc;
 
-	addr = arch_get_unmapped_area(filp, addr, len, pgoff, flags);
-	if (addr & ~PAGE_MASK)
-		return addr;
-	if (unlikely(mm->context.asce_limit < addr + len)) {
-		rc = crst_table_upgrade(mm, addr + len);
+	area = arch_get_unmapped_area(filp, addr, len, pgoff, flags);
+	if (!(area & ~PAGE_MASK))
+		return area;
+	if (area == -ENOMEM &&
+	    !test_thread_flag(TIF_31BIT) && TASK_SIZE < (1UL << 53)) {
+		/* Upgrade the page table to 4 levels and retry. */
+		rc = crst_table_upgrade(mm, 1UL << 53);
 		if (rc)
 			return (unsigned long) rc;
+		area = arch_get_unmapped_area(filp, addr, len, pgoff, flags);
 	}
-	return addr;
+	return area;
 }
 
 static unsigned long
-s390_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
+s390_get_unmapped_area_topdown(struct file *filp, const unsigned long addr,
 			  const unsigned long len, const unsigned long pgoff,
 			  const unsigned long flags)
 {
 	struct mm_struct *mm = current->mm;
-	unsigned long addr = addr0;
+	unsigned long area;
 	int rc;
 
-	addr = arch_get_unmapped_area_topdown(filp, addr, len, pgoff, flags);
-	if (addr & ~PAGE_MASK)
-		return addr;
-	if (unlikely(mm->context.asce_limit < addr + len)) {
-		rc = crst_table_upgrade(mm, addr + len);
+	area = arch_get_unmapped_area_topdown(filp, addr, len, pgoff, flags);
+	if (!(area & ~PAGE_MASK))
+		return area;
+	if (area == -ENOMEM &&
+	    !test_thread_flag(TIF_31BIT) && TASK_SIZE < (1UL << 53)) {
+		/* Upgrade the page table to 4 levels and retry. */
+		rc = crst_table_upgrade(mm, 1UL << 53);
 		if (rc)
 			return (unsigned long) rc;
+		area = arch_get_unmapped_area_topdown(filp, addr, len,
+						      pgoff, flags);
 	}
-	return addr;
+	return area;
 }
 /*
  * This function, called very early during the creation of a new
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 0767827540b..6b6ddc4ea02 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -117,6 +117,7 @@ repeat:
 		crst_table_init(table, entry);
 		pgd_populate(mm, (pgd_t *) table, (pud_t *) pgd);
 		mm->pgd = (pgd_t *) table;
+		mm->task_size = mm->context.asce_limit;
 		table = NULL;
 	}
 	spin_unlock(&mm->page_table_lock);
@@ -154,6 +155,7 @@ void crst_table_downgrade(struct mm_struct *mm, unsigned long limit)
 			BUG();
 		}
 		mm->pgd = (pgd_t *) (pgd_val(*pgd) & _REGION_ENTRY_ORIGIN);
+		mm->task_size = mm->context.asce_limit;
 		crst_table_free(mm, (unsigned long *) pgd);
 	}
 	update_mm(mm, current);