I think the code gets easier to read when we give symbolic names
to some of the operations we're performing.  I was sure we needed
this when I saw the header being built like this:

        ...
        buf[2] = sizeof(unsigned long)
        buf[3] = sizeof(unsigned long)

I really couldn't remember what either field did ;(

Signed-off-by: Dave Hansen <[EMAIL PROTECTED]>
---

 lxc-dave/fs/proc/task_mmu.c |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff -puN fs/proc/task_mmu.c~pagemap-use-ENTRY_SIZE fs/proc/task_mmu.c
--- lxc/fs/proc/task_mmu.c~pagemap-use-ENTRY_SIZE       2007-08-07 
15:30:53.000000000 -0700
+++ lxc-dave/fs/proc/task_mmu.c 2007-08-07 15:30:53.000000000 -0700
@@ -560,14 +560,15 @@ struct pagemapread {
        unsigned long __user *out;
 };
 
+#define PAGEMAP_ENTRY_SIZE_BYTES sizeof(unsigned long)
+
 static int add_to_pagemap(unsigned long addr, unsigned long pfn,
                          struct pagemapread *pm)
 {
        __put_user(pfn, pm->out);
        pm->out++;
-       pm->pos += sizeof(unsigned long);
-       pm->count -= sizeof(unsigned long);
-       pm->next = addr + PAGE_SIZE;
+       pm->pos += PAGEMAP_ENTRY_SIZE_BYTES;
+       pm->count -= PAGEMAP_ENTRY_SIZE_BYTES;
        return 0;
 }
 
@@ -653,13 +654,13 @@ static ssize_t pagemap_read(struct file 
                goto out;
 
        ret = -EIO;
-       svpfn = src / sizeof(unsigned long);
+       svpfn = src / PAGEMAP_ENTRY_SIZE_BYTES;
        addr = PAGE_SIZE * svpfn;
-       if (svpfn * sizeof(unsigned long) != src)
+       if (svpfn * PAGEMAP_ENTRY_SIZE_BYTES != src)
                goto out;
        evpfn = min((src + count) / sizeof(unsigned long),
                    ((~0UL) >> PAGE_SHIFT) + 1);
-       count = (evpfn - svpfn) * sizeof(unsigned long);
+       count = (evpfn - svpfn) * PAGEMAP_ENTRY_SIZE_BYTES;
        end = PAGE_SIZE * evpfn;
        //printk("src %ld svpfn %d evpfn %d count %d\n", src, svpfn, evpfn, 
count);
 
_
-
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