Re: 2.6.21-rc2-mm2: drivers/net/wireless/libertas/debugfs.c addr bogosity

Randy Dunlap
2007-03-09T17:20:23Z

On Fri, 9 Mar 2007 09:19:07 -0500 John W. Linville wrote:

> Probably should copy me and linux-wireless@vger.kernel.org. Other than
> that, this looks fine to me. I'll queue it up shortly.
>
> John
>
> On Fri, Mar 09, 2007 at 01:11:46PM +1100, Tony Breeds wrote:
> > On Wed, Mar 07, 2007 at 03:00:57PM -0800, Andrew Morton wrote:
> > > On Wed, 7 Mar 2007 23:41:16 +0100
> > > Adrian Bunk <bunk@stusta.de> wrote:
> > >
> > > > On Tue, Mar 06, 2007 at 12:44:08AM -0800, Andrew Morton wrote:
> > > > >...
> > > > > Changes since 2.6.20-rc2-mm1:
> > > > >...
> > > > > git-netdev-all.patch
> > > > >...
> > > > > git trees
> > > > >...
> > > >
> > > > drivers/net/wireless/libertas/debugfs.c contains:
> > > > #define item_addr(n) ((u32) &((wlan_adapter *)0)->n)
> > > >
> > > > This is wrong on 64bit architectures.
> > >
> > > Is OK - it is simply yet another reimplementation of offsetof(). Hint.
> >
> > Perhaps something like?
> >
> > Against 2.6.21-rc3-mm2
> >
> > From: Tony Breeds <tony@bakeyournoodle.com>
> >
> > Cleanup drivers/net/wireless/libertas/debugfs.c to use standard kernel macros and functions.
> >
> > Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
> >
> > ---
> > only compile tested on x86
> >
> > debugfs.c | 41 ++++-------------------------------------
> > 1 file changed, 4 insertions(+), 37 deletions(-)
> >
> > diff --git a/drivers/net/wireless/libertas/debugfs.c b/drivers/net/wireless/libertas/debugfs.c
> > index 3ad1e03..51dfd20 100644
> > --- a/drivers/net/wireless/libertas/debugfs.c
> > +++ b/drivers/net/wireless/libertas/debugfs.c
> > @@ -1772,8 +1772,8 @@ void libertas_debugfs_remove_one(wlan_private *priv)
> >
> > /* debug entry */
> >
> > -#define item_size(n) (sizeof ((wlan_adapter *)0)->n)
> > -#define item_addr(n) ((u32) &((wlan_adapter *)0)->n)
> > +#define item_size(n) (FIELD_SIZEOF(wlan_adapter, n))

Good to use FIELD_SIZEOF(), but in general, we prefer to use it
directly, not in yet another wrapper.

> > +#define item_addr(n) (offsetof(wlan_adapter, n))
> >
> > struct debug_data {
> > char name[32];
> > @@ -1789,40 +1789,7 @@ static struct debug_data items[] = {
> > {"psstate", item_size(psstate), item_addr(psstate)},
> > };
> >
> > -static int num_of_items = sizeof(items) / sizeof(items[0]);
> > -
> > -/**
> > - * @brief convert string to number
> > - *
> > - * @param s pointer to numbered string
> > - * @return converted number from string s
> > - */
> > -static int string_to_number(char *s)
> > -{
> > - int r = 0;
> > - int base = 0;
> > -
> > - if ((strncmp(s, "0x", 2) == 0) || (strncmp(s, "0X", 2) == 0))
> > - base = 16;
> > - else
> > - base = 10;
> > -
> > - if (base == 16)
> > - s += 2;
> > -
> > - for (s = s; *s != 0; s++) {
> > - if ((*s >= 48) && (*s <= 57))
> > - r = (r * base) + (*s - 48);
> > - else if ((*s >= 65) && (*s <= 70))
> > - r = (r * base) + (*s - 55);
> > - else if ((*s >= 97) && (*s <= 102))
> > - r = (r * base) + (*s - 87);
> > - else
> > - break;
> > - }
> > -
> > - return r;
> > -}
> > +static int num_of_items = ARRAY_SIZE(items);
> >
> > /**
> > * @brief proc read function
> > @@ -1912,7 +1879,7 @@ static int wlan_debugfs_write(struct file *f, const char __user *buf,
> > if (!p2)
> > break;
> > p2++;
> > - r = string_to_number(p2);
> > + r = simple_strtoul(p2, NULL, 0);
> > if (d[i].size == 1)
> > *((u8 *) d[i].addr) = (u8) r;
> > else if (d[i].size == 2)

---
~Randy
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