untangle the do_mremap() mess

This backports the following upstream commits all as one patch:
	54f5de709984bae0d31d823ff03de755f9dcac54
	ecc1a8993751de4e82eb18640d631dae1f626bd6
	1a0ef85f84feb13f07b604fcf5b90ef7c2b5c82f
	f106af4e90eadd76cfc0b5325f659619e08fb762
	097eed103862f9c6a97f2e415e21d1134017b135
	935874141df839c706cd6cdc438e85eb69d1525e
	0ec62d290912bb4b989be7563851bc364ec73b56
	c4caa778157dbbf04116f0ac2111e389b5cd7a29
	2ea1d13f64efdf49319e86c87d9ba38c30902782
	570dcf2c15463842e384eb597a87c1e39bead99b
	564b3bffc619dcbdd160de597b0547a7017ea010
	0067bd8a55862ac9dd212bd1c4f6f5bff1ca1301
	f8b7256096a20436f6d0926747e3ac3d64c81d24
	8c7b49b3ecd48923eb64ff57e07a1cdb74782970
	9206de95b1ea68357996ec02be5db0638a0de2c1
	2c6a10161d0b5fc047b5bd81b03693b9af99fab5
	05d72faa6d13c9d857478a5d35c85db9adada685
	bb52d6694002b9d632bb355f64daa045c6293a4e
	e77414e0aad6a1b063ba5e5750c582c75327ea6a
	aa65607373a4daf2010e8c3867b6317619f3c1a3

Backport done by Greg Kroah-Hartman.  Only minor tweaks were needed.

Cc: David S. Miller <davem@davemloft.net>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

5 files changed, 23 insertions, 100 deletions

diff --git a/arch/sparc/kernel/sys_sparc_32.c b/arch/sparc/kernel/sys_sparc_32.c
index 03035c852a43..3a82e65d8db2 100644
--- a/arch/sparc/kernel/sys_sparc_32.c
+++ b/arch/sparc/kernel/sys_sparc_32.c
@@ -45,7 +45,8 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 		/* We do not accept a shared mapping if it would violate
 		 * cache aliasing constraints.
 		 */
-		if ((flags & MAP_SHARED) && (addr & (SHMLBA - 1)))
+		if ((flags & MAP_SHARED) &&
+		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
 			return -EINVAL;
 		return addr;
 	}
@@ -79,15 +80,6 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 	}
 }
 
-asmlinkage unsigned long sparc_brk(unsigned long brk)
-{
-	if(ARCH_SUN4C) {
-		if ((brk & 0xe0000000) != (current->mm->brk & 0xe0000000))
-			return current->mm->brk;
-	}
-	return sys_brk(brk);
-}
-
 /*
  * sys_pipe() is the normal C calling standard for creating
  * a pipe. It's not the way unix traditionally does this, though.
@@ -234,31 +226,6 @@ int sparc_mmap_check(unsigned long addr, unsigned long len)
 }
 
 /* Linux version of mmap */
-static unsigned long do_mmap2(unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags, unsigned long fd,
-	unsigned long pgoff)
-{
-	struct file * file = NULL;
-	unsigned long retval = -EBADF;
-
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	len = PAGE_ALIGN(len);
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	down_write(&current->mm->mmap_sem);
-	retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return retval;
-}
 
 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
 	unsigned long prot, unsigned long flags, unsigned long fd,
@@ -266,14 +233,16 @@ asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
 {
 	/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
 	   we have. */
-	return do_mmap2(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT - 12));
+	return sys_mmap_pgoff(addr, len, prot, flags, fd,
+			      pgoff >> (PAGE_SHIFT - 12));
 }
 
 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
 	unsigned long prot, unsigned long flags, unsigned long fd,
 	unsigned long off)
 {
-	return do_mmap2(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
+	/* no alignment check? */
+	return sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 }
 
 long sparc_remap_file_pages(unsigned long start, unsigned long size,
@@ -287,27 +256,6 @@ long sparc_remap_file_pages(unsigned long start, unsigned long size,
 				    (pgoff >> (PAGE_SHIFT - 12)), flags);
 }
 
-extern unsigned long do_mremap(unsigned long addr,
-	unsigned long old_len, unsigned long new_len,
-	unsigned long flags, unsigned long new_addr);
-                
-asmlinkage unsigned long sparc_mremap(unsigned long addr,
-	unsigned long old_len, unsigned long new_len,
-	unsigned long flags, unsigned long new_addr)
-{
-	unsigned long ret = -EINVAL;
-
-	if (unlikely(sparc_mmap_check(addr, old_len)))
-		goto out;
-	if (unlikely(sparc_mmap_check(new_addr, new_len)))
-		goto out;
-	down_write(&current->mm->mmap_sem);
-	ret = do_mremap(addr, old_len, new_len, flags, new_addr);
-	up_write(&current->mm->mmap_sem);
-out:
-	return ret;       
-}
-
 /* we come to here via sys_nis_syscall so it can setup the regs argument */
 asmlinkage unsigned long
 c_sys_nis_syscall (struct pt_regs *regs)
diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
index e2d102447a43..cfa0e19abe3b 100644
--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -317,10 +317,14 @@ bottomup:
 unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
 {
 	unsigned long align_goal, addr = -ENOMEM;
+	unsigned long (*get_area)(struct file *, unsigned long,
+				  unsigned long, unsigned long, unsigned long);
+
+	get_area = current->mm->get_unmapped_area;
 
 	if (flags & MAP_FIXED) {
 		/* Ok, don't mess with it. */
-		return get_unmapped_area(NULL, orig_addr, len, pgoff, flags);
+		return get_area(NULL, orig_addr, len, pgoff, flags);
 	}
 	flags &= ~MAP_SHARED;
 
@@ -333,7 +337,7 @@ unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, u
 		align_goal = (64UL * 1024);
 
 	do {
-		addr = get_unmapped_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
+		addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
 		if (!(addr & ~PAGE_MASK)) {
 			addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
 			break;
@@ -351,7 +355,7 @@ unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, u
 	 * be obtained.
 	 */
 	if (addr & ~PAGE_MASK)
-		addr = get_unmapped_area(NULL, orig_addr, len, pgoff, flags);
+		addr = get_area(NULL, orig_addr, len, pgoff, flags);
 
 	return addr;
 }
@@ -399,18 +403,6 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
 	}
 }
 
-SYSCALL_DEFINE1(sparc_brk, unsigned long, brk)
-{
-	/* People could try to be nasty and use ta 0x6d in 32bit programs */
-	if (test_thread_flag(TIF_32BIT) && brk >= STACK_TOP32)
-		return current->mm->brk;
-
-	if (unlikely(straddles_64bit_va_hole(current->mm->brk, brk)))
-		return current->mm->brk;
-
-	return sys_brk(brk);
-}
-                                                                
 /*
  * sys_pipe() is the normal C calling standard for creating
  * a pipe. It's not the way unix traditionally does this, though.
@@ -568,23 +560,13 @@ SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
 		unsigned long, prot, unsigned long, flags, unsigned long, fd,
 		unsigned long, off)
 {
-	struct file * file = NULL;
-	unsigned long retval = -EBADF;
-
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	len = PAGE_ALIGN(len);
+	unsigned long retval = -EINVAL;
 
-	down_write(&current->mm->mmap_sem);
-	retval = do_mmap(file, addr, len, prot, flags, off);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
+	if ((off + PAGE_ALIGN(len)) < off)
+		goto out;
+	if (off & ~PAGE_MASK)
+		goto out;
+	retval = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 out:
 	return retval;
 }
@@ -614,12 +596,6 @@ SYSCALL_DEFINE5(64_mremap, unsigned long, addr,	unsigned long, old_len,
 
 	if (test_thread_flag(TIF_32BIT))
 		goto out;
-	if (unlikely(new_len >= VA_EXCLUDE_START))
-		goto out;
-	if (unlikely(sparc_mmap_check(addr, old_len)))
-		goto out;
-	if (unlikely(sparc_mmap_check(new_addr, new_len)))
-		goto out;
 
 	down_write(&current->mm->mmap_sem);
 	ret = do_mremap(addr, old_len, new_len, flags, new_addr);
diff --git a/arch/sparc/kernel/systbls.h b/arch/sparc/kernel/systbls.h
index a63c5d2d9849..d2f999ae2b85 100644
--- a/arch/sparc/kernel/systbls.h
+++ b/arch/sparc/kernel/systbls.h
@@ -9,7 +9,6 @@
 struct new_utsname;
 
 extern asmlinkage unsigned long sys_getpagesize(void);
-extern asmlinkage unsigned long sparc_brk(unsigned long brk);
 extern asmlinkage long sparc_pipe(struct pt_regs *regs);
 extern asmlinkage long sys_ipc(unsigned int call, int first,
 			       unsigned long second,
diff --git a/arch/sparc/kernel/systbls_32.S b/arch/sparc/kernel/systbls_32.S
index 0f1658d37490..14f950afcd67 100644
--- a/arch/sparc/kernel/systbls_32.S
+++ b/arch/sparc/kernel/systbls_32.S
@@ -19,7 +19,7 @@ sys_call_table:
 /*0*/	.long sys_restart_syscall, sys_exit, sys_fork, sys_read, sys_write
 /*5*/	.long sys_open, sys_close, sys_wait4, sys_creat, sys_link
 /*10*/  .long sys_unlink, sunos_execv, sys_chdir, sys_chown16, sys_mknod
-/*15*/	.long sys_chmod, sys_lchown16, sparc_brk, sys_nis_syscall, sys_lseek
+/*15*/	.long sys_chmod, sys_lchown16, sys_brk, sys_nis_syscall, sys_lseek
 /*20*/	.long sys_getpid, sys_capget, sys_capset, sys_setuid16, sys_getuid16
 /*25*/	.long sys_vmsplice, sys_ptrace, sys_alarm, sys_sigaltstack, sys_pause
 /*30*/	.long sys_utime, sys_lchown, sys_fchown, sys_access, sys_nice
@@ -67,7 +67,7 @@ sys_call_table:
 /*235*/	.long sys_fstatfs64, sys_llseek, sys_mlock, sys_munlock, sys_mlockall
 /*240*/	.long sys_munlockall, sys_sched_setparam, sys_sched_getparam, sys_sched_setscheduler, sys_sched_getscheduler
 /*245*/	.long sys_sched_yield, sys_sched_get_priority_max, sys_sched_get_priority_min, sys_sched_rr_get_interval, sys_nanosleep
-/*250*/	.long sparc_mremap, sys_sysctl, sys_getsid, sys_fdatasync, sys_nfsservctl
+/*250*/	.long sys_mremap, sys_sysctl, sys_getsid, sys_fdatasync, sys_nfsservctl
 /*255*/	.long sys_sync_file_range, sys_clock_settime, sys_clock_gettime, sys_clock_getres, sys_clock_nanosleep
 /*260*/	.long sys_sched_getaffinity, sys_sched_setaffinity, sys_timer_settime, sys_timer_gettime, sys_timer_getoverrun
 /*265*/	.long sys_timer_delete, sys_timer_create, sys_nis_syscall, sys_io_setup, sys_io_destroy
diff --git a/arch/sparc/kernel/systbls_64.S b/arch/sparc/kernel/systbls_64.S
index 009825f6e73c..f63c871eebb7 100644
--- a/arch/sparc/kernel/systbls_64.S
+++ b/arch/sparc/kernel/systbls_64.S
@@ -21,7 +21,7 @@ sys_call_table32:
 /*0*/	.word sys_restart_syscall, sys32_exit, sys_fork, sys_read, sys_write
 /*5*/	.word sys32_open, sys_close, sys32_wait4, sys32_creat, sys_link
 /*10*/  .word sys_unlink, sunos_execv, sys_chdir, sys_chown16, sys32_mknod
-/*15*/	.word sys_chmod, sys_lchown16, sys_sparc_brk, sys32_perfctr, sys32_lseek
+/*15*/	.word sys_chmod, sys_lchown16, sys_brk, sys32_perfctr, sys32_lseek
 /*20*/	.word sys_getpid, sys_capget, sys_capset, sys_setuid16, sys_getuid16
 /*25*/	.word sys32_vmsplice, compat_sys_ptrace, sys_alarm, sys32_sigaltstack, sys_pause
 /*30*/	.word compat_sys_utime, sys_lchown, sys_fchown, sys32_access, sys32_nice
@@ -96,7 +96,7 @@ sys_call_table:
 /*0*/	.word sys_restart_syscall, sparc_exit, sys_fork, sys_read, sys_write
 /*5*/	.word sys_open, sys_close, sys_wait4, sys_creat, sys_link
 /*10*/  .word sys_unlink, sys_nis_syscall, sys_chdir, sys_chown, sys_mknod
-/*15*/	.word sys_chmod, sys_lchown, sys_sparc_brk, sys_perfctr, sys_lseek
+/*15*/	.word sys_chmod, sys_lchown, sys_brk, sys_perfctr, sys_lseek
 /*20*/	.word sys_getpid, sys_capget, sys_capset, sys_setuid, sys_getuid
 /*25*/	.word sys_vmsplice, sys_ptrace, sys_alarm, sys_sigaltstack, sys_nis_syscall
 /*30*/	.word sys_utime, sys_nis_syscall, sys_nis_syscall, sys_access, sys_nice