From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Yury Norov <yury.norov@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Rasmus Villemoes <linux@rasmusvillemoes.dk>,
Dmitry Torokhov <dmitry.torokhov@gmail.com>,
"David S . Miller" <davem@davemloft.net>,
Stephen Rothwell <sfr@canb.auug.org.au>,
Amritha Nambiar <amritha.nambiar@intel.com>,
Willem de Bruijn <willemb@google.com>,
Kees Cook <keescook@chromium.org>,
Matthew Wilcox <willy@infradead.org>,
"Tobin C . Harding" <tobin@kernel.org>,
Will Deacon <will.deacon@arm.com>,
Miklos Szeredi <mszeredi@redhat.com>,
Vineet Gupta <vineet.gupta1@synopsys.com>,
Chris Wilson <chris@chris-wilson.co.uk>,
Arnaldo Carvalho de Melo <acme@redhat.com>,
linux-kernel@vger.kernel.org, Yury Norov <ynorov@marvell.com>,
Jens Axboe <axboe@kernel.dk>,
Steffen Klassert <steffen.klassert@secunet.com>
Subject: Re: [PATCH 4/7] lib: make bitmap_parse_user a wrapper on bitmap_parse
Date: Wed, 8 May 2019 11:47:32 +0300 [thread overview]
Message-ID: <20190508084732.GC9224@smile.fi.intel.com> (raw)
In-Reply-To: <20190501010636.30595-5-ynorov@marvell.com>
On Tue, Apr 30, 2019 at 06:06:33PM -0700, Yury Norov wrote:
> Currently we parse user data byte after byte which leads to
> overcomplicating of parsing algorithm. There are no performance
> critical users of bitmap_parse_user(), and so we can duplicate
> user data to kernel buffer and simply call bitmap_parselist().
> This rework lets us unify and simplify bitmap_parse() and
> bitmap_parse_user(), which is done in the following patch.
>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Signed-off-by: Yury Norov <ynorov@marvell.com>
> ---
> lib/bitmap.c | 20 ++++++++++----------
> 1 file changed, 10 insertions(+), 10 deletions(-)
>
> diff --git a/lib/bitmap.c b/lib/bitmap.c
> index f235434df87b..300732031fad 100644
> --- a/lib/bitmap.c
> +++ b/lib/bitmap.c
> @@ -434,22 +434,22 @@ EXPORT_SYMBOL(__bitmap_parse);
> * then it must be terminated with a \0.
> * @maskp: pointer to bitmap array that will contain result.
> * @nmaskbits: size of bitmap, in bits.
> - *
> - * Wrapper for __bitmap_parse(), providing it with user buffer.
> - *
> - * We cannot have this as an inline function in bitmap.h because it needs
> - * linux/uaccess.h to get the access_ok() declaration and this causes
> - * cyclic dependencies.
> */
> int bitmap_parse_user(const char __user *ubuf,
> unsigned int ulen, unsigned long *maskp,
> int nmaskbits)
> {
> - if (!access_ok(ubuf, ulen))
> - return -EFAULT;
> - return __bitmap_parse((const char __force *)ubuf,
> - ulen, 1, maskp, nmaskbits);
> + char *buf;
> + int ret;
>
> + buf = memdup_user_nul(ubuf, ulen);
> + if (IS_ERR(buf))
> + return PTR_ERR(buf);
> +
> + ret = bitmap_parse(buf, ulen, maskp, nmaskbits);
> +
> + kfree(buf);
> + return ret;
> }
> EXPORT_SYMBOL(bitmap_parse_user);
>
> --
> 2.17.1
>
--
With Best Regards,
Andy Shevchenko
next prev parent reply other threads:[~2019-05-08 8:47 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-01 1:06 [PATCH 0/7] lib: rework bitmap_parse Yury Norov
2019-05-01 1:06 ` [PATCH 1/7] lib/string: add strnchrnul() Yury Norov
2019-05-08 8:47 ` Andy Shevchenko
2019-05-01 1:06 ` [PATCH 2/7] bitops: more BITS_TO_* macros Yury Norov
2019-05-08 8:47 ` Andy Shevchenko
2019-05-01 1:06 ` [PATCH 3/7] lib: add test for bitmap_parse() Yury Norov
2019-05-08 8:47 ` Andy Shevchenko
2019-05-01 1:06 ` [PATCH 4/7] lib: make bitmap_parse_user a wrapper on bitmap_parse Yury Norov
2019-05-08 8:47 ` Andy Shevchenko [this message]
2019-05-01 1:06 ` [PATCH 5/7] lib: rework bitmap_parse() Yury Norov
2019-05-08 8:46 ` Andy Shevchenko
2019-05-10 2:26 ` Yury Norov
2019-05-24 2:51 ` Andrew Morton
2019-05-01 1:06 ` [PATCH 6/7] lib: new testcases for bitmap_parse{_user} Yury Norov
2019-05-08 8:47 ` Andy Shevchenko
2019-05-01 1:06 ` [PATCH 7/7] cpumask: don't calculate length of the input string Yury Norov
2019-05-08 8:48 ` Andy Shevchenko
2019-05-07 21:04 ` [PATCH 0/7] lib: rework bitmap_parse Yury Norov
2019-07-21 21:27 [PATCH v3 " Yury Norov
2019-07-21 21:27 ` [PATCH 4/7] lib: make bitmap_parse_user a wrapper on bitmap_parse Yury Norov
2019-09-09 3:30 [PATCH v4 0/7] lib: rework bitmap_parse Yury Norov
2019-09-09 3:30 ` [PATCH 4/7] lib: make bitmap_parse_user a wrapper on bitmap_parse Yury Norov
2020-01-02 4:30 [PATCH v5 0/7] lib: rework bitmap_parse Yury Norov
2020-01-02 4:30 ` [PATCH 4/7] lib: make bitmap_parse_user a wrapper on bitmap_parse Yury Norov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190508084732.GC9224@smile.fi.intel.com \
--to=andriy.shevchenko@linux.intel.com \
--cc=acme@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=amritha.nambiar@intel.com \
--cc=axboe@kernel.dk \
--cc=chris@chris-wilson.co.uk \
--cc=davem@davemloft.net \
--cc=dmitry.torokhov@gmail.com \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@rasmusvillemoes.dk \
--cc=mszeredi@redhat.com \
--cc=sfr@canb.auug.org.au \
--cc=steffen.klassert@secunet.com \
--cc=tobin@kernel.org \
--cc=vineet.gupta1@synopsys.com \
--cc=will.deacon@arm.com \
--cc=willemb@google.com \
--cc=willy@infradead.org \
--cc=ynorov@marvell.com \
--cc=yury.norov@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).