From 74aaf57b5c2b979a68207f71fa8eb2885a89f44d Mon Sep 17 00:00:00 2001
From: Thomas Tuttle <ttuttle@google.com>
Date: Thu, 5 Jun 2008 22:46:31 -0700
Subject: [PATCH] --- yaml --- r: 97807 b: refs/heads/master c:
 aae8679b0ebcaa92f99c1c3cb0cd651594a43915 h: refs/heads/master i:   97805:
 f5f5dbbb960fb34c0a78a51ff3115f60820e181f   97803:
 a9cf002ff6087852f60ff15d187cb18c4a7f3947   97799:
 8f9fe39fe5a9793beb0134eab30a4ffbce1ae649   97791:
 9c65fb13770b628b572c6a470c072768f060ec91 v: v3

---
 [refs]                   |  2 +-
 trunk/fs/proc/task_mmu.c | 28 +++++++++-------------------
 2 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/[refs] b/[refs]
index 9e5f3a8451ea..10d3e19b34f3 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d1ee2971f5bd8a16bc5ecfe1b00e14b4fe407c4f
+refs/heads/master: aae8679b0ebcaa92f99c1c3cb0cd651594a43915
diff --git a/trunk/fs/proc/task_mmu.c b/trunk/fs/proc/task_mmu.c
index 88717c0f941b..17403629e330 100644
--- a/trunk/fs/proc/task_mmu.c
+++ b/trunk/fs/proc/task_mmu.c
@@ -496,7 +496,7 @@ const struct file_operations proc_clear_refs_operations = {
 };
 
 struct pagemapread {
-	char __user *out, *end;
+	u64 __user *out, *end;
 };
 
 #define PM_ENTRY_BYTES      sizeof(u64)
@@ -519,21 +519,11 @@ struct pagemapread {
 static int add_to_pagemap(unsigned long addr, u64 pfn,
 			  struct pagemapread *pm)
 {
-	/*
-	 * Make sure there's room in the buffer for an
-	 * entire entry.  Otherwise, only copy part of
-	 * the pfn.
-	 */
-	if (pm->out + PM_ENTRY_BYTES >= pm->end) {
-		if (copy_to_user(pm->out, &pfn, pm->end - pm->out))
-			return -EFAULT;
-		pm->out = pm->end;
-		return PM_END_OF_BUFFER;
-	}
-
 	if (put_user(pfn, pm->out))
 		return -EFAULT;
-	pm->out += PM_ENTRY_BYTES;
+	pm->out++;
+	if (pm->out >= pm->end)
+		return PM_END_OF_BUFFER;
 	return 0;
 }
 
@@ -634,7 +624,7 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
 
 	ret = -EINVAL;
 	/* file position must be aligned */
-	if (*ppos % PM_ENTRY_BYTES)
+	if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
 		goto out_task;
 
 	ret = 0;
@@ -664,8 +654,8 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
 		goto out_pages;
 	}
 
-	pm.out = buf;
-	pm.end = buf + count;
+	pm.out = (u64 *)buf;
+	pm.end = (u64 *)(buf + count);
 
 	if (!ptrace_may_attach(task)) {
 		ret = -EIO;
@@ -690,9 +680,9 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
 		if (ret == PM_END_OF_BUFFER)
 			ret = 0;
 		/* don't need mmap_sem for these, but this looks cleaner */
-		*ppos += pm.out - buf;
+		*ppos += (char *)pm.out - buf;
 		if (!ret)
-			ret = pm.out - buf;
+			ret = (char *)pm.out - buf;
 	}
 
 out_pages: