From: Bart Van Assche <bvanassche@acm.org>
To: Martijn Coenen <maco@android.com>, axboe@kernel.dk, hch@lst.de
Cc: Chaitanya.Kulkarni@wdc.com, linux-block@vger.kernel.org,
linux-kernel@vger.kernel.org, kernel-team@android.com
Subject: Re: [PATCH] loop: Add LOOP_SET_FD_WITH_OFFSET ioctl.
Date: Sun, 29 Mar 2020 13:19:59 -0700 [thread overview]
Message-ID: <81b67b60-5b2f-f98f-f5df-1ddc2b2ae6b4@acm.org> (raw)
In-Reply-To: <20200329140459.18155-1-maco@android.com>
On 2020-03-29 07:04, Martijn Coenen wrote:
> -static int loop_set_fd(struct loop_device *lo, fmode_t mode,
> - struct block_device *bdev, unsigned int arg)
> +static int loop_set_fd_with_offset(struct loop_device *lo, fmode_t mode,
> + struct block_device *bdev, unsigned int arg, loff_t offset)
Since this function has to be modified, please add an additional patch
to rename 'arg' into 'fd'. Additionally, how about renaming
"loop_set_fd_with_offset" into "loop_set_fd_and_offset"? I think the
latter name reflects more clearly the purpose of this function.
> @@ -1624,6 +1625,17 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode,
> break;
> case LOOP_GET_STATUS64:
> return loop_get_status64(lo, (struct loop_info64 __user *) arg);
> + case LOOP_SET_FD_WITH_OFFSET: {
> + struct loop_fd_with_offset fdwo;
> +
> + if (copy_from_user(&fdwo,
> + (struct loop_fd_with_offset __user *) arg,
> + sizeof(struct loop_fd_with_offset)))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The kernel code that I'm familiar with uses sizeof(<variable name>)
instead of sizeof(<struct name>). That makes it less likely that
changing the type of the variable will introduce a mismatch between the
sizeof() expression and the size of the variable.
Thanks,
Bart.
next prev parent reply other threads:[~2020-03-29 20:20 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-29 14:04 [PATCH] loop: Add LOOP_SET_FD_WITH_OFFSET ioctl Martijn Coenen
2020-03-29 16:48 ` Chaitanya Kulkarni
2020-03-29 20:19 ` Bart Van Assche [this message]
2020-03-30 1:00 ` Ming Lei
2020-03-30 8:06 ` Martijn Coenen
2020-03-31 7:48 ` Christoph Hellwig
2020-03-31 11:25 ` Martijn Coenen
2020-03-31 11:40 Martijn Coenen
2020-03-31 11:42 ` Martijn Coenen
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