From: Joe Perches <joe@perches.com>
To: mgross@linux.intel.com, markgross@kernel.org, arnd@arndb.de,
bp@suse.de, damien.lemoal@wdc.com, dragan.cvetic@xilinx.com,
gregkh@linuxfoundation.org, corbet@lwn.net,
leonard.crestez@nxp.com, palmerdabbelt@google.com,
paul.walmsley@sifive.com, peng.fan@nxp.com, robh+dt@kernel.org,
shawnguo@kernel.org
Cc: linux-kernel@vger.kernel.org, Seamus Kelly <seamus.kelly@intel.com>
Subject: Re: [PATCH 22/22] xlink-core: factorize xlink_ioctl function by creating sub-functions for each ioctl command
Date: Wed, 09 Dec 2020 00:30:46 -0800 [thread overview]
Message-ID: <f54fcb1e9f90b529826d8d6abb2ae99b15108d16.camel@perches.com> (raw)
In-Reply-To: <20201201223511.65542-23-mgross@linux.intel.com>
On Tue, 2020-12-01 at 14:35 -0800, mgross@linux.intel.com wrote:
> Refactor the too large IOCTL function to call helper functions.
[]
> diff --git a/drivers/misc/xlink-core/xlink-ioctl.c b/drivers/misc/xlink-core/xlink-ioctl.c
[]
> +int ioctl_write_data(unsigned long arg)
> +{
> + struct xlink_handle devh = {0};
> + struct xlinkwritedata wr = {0};
> + int rc = 0;
> +
> + if (copy_from_user(&wr, (void __user *)arg,
> + sizeof(struct xlinkwritedata)))
> + return -EFAULT;
> + if (copy_from_user(&devh, (void __user *)wr.handle,
> + sizeof(struct xlink_handle)))
> + return -EFAULT;
> + if (wr.size <= XLINK_MAX_DATA_SIZE) {
> + rc = xlink_write_data_user(&devh, wr.chan, wr.pmessage,
> + wr.size);
> + if (copy_to_user((void __user *)wr.return_code, (void *)&rc,
> + sizeof(rc)))
> + return -EFAULT;
> + } else {
> + return -EFAULT;
> + }
Please reverse the test to reduce indentation
if (wr.size > XLINK_MAX_DATA_SIZE)
return -EFAULT;
rc = xlink_write_data_user(&devh, wr.chan, wr.pmessage, wr.size);
if (copy_to_user((void __user *)wr.return_code, (void *)&rc, sizeof(rc)))
return -EFAULT;
return rc;
The last 3 lines here are repeated multiple times in many functions.
It might be sensible to add something like:
int copy_result_to_user(u32 *where, int rc)
{
if (copy_to_user((void __user *)where, &rc, sizeof(rc)))
return -EFAULT;
return rc;
}
so this could be written
rc = xlink_write_data_user(&devh, wr.chan, wr.pmessage, wr.size);
return copy_result_to_user(wr.return_code, rc);
IMO: return_code isn't a great name for a pointer as it rather
indicates a value not an address and there's an awful lot of
casting to __user in all this code that perhaps should be marked
in the struct definitions rather than inside the function uses.
> +}
> +
> +int ioctl_write_control_data(unsigned long arg)
> +{
> + struct xlink_handle devh = {0};
All of these initializations with {0} should use {} instead as
the first element of whatever struct is not guaranteed to be
assignable as an int and gcc/clang guarantee 0 initialization
> + struct xlinkwritedata wr = {0};
> + u8 volbuf[XLINK_MAX_BUF_SIZE];
> + int rc = 0;
> +
> + if (copy_from_user(&wr, (void __user *)arg,
> + sizeof(struct xlinkwritedata)))
> + return -EFAULT;
> + if (copy_from_user(&devh, (void __user *)wr.handle,
> + sizeof(struct xlink_handle)))
> + return -EFAULT;
> + if (wr.size <= XLINK_MAX_CONTROL_DATA_SIZE) {
> + if (copy_from_user(volbuf, (void __user *)wr.pmessage,
> + wr.size))
> + return -EFAULT;
> + rc = xlink_write_control_data(&devh, wr.chan, volbuf,
> + wr.size);
> + if (copy_to_user((void __user *)wr.return_code,
> + (void *)&rc, sizeof(rc)))
> + return -EFAULT;
> + } else {
> + return -EFAULT;
Same test reversal and deindentation please.
> + }
> + return rc;
> +}
> +
next prev parent reply other threads:[~2020-12-09 8:32 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-01 22:34 [PATCH 00/22] Intel Vision Processing Unit base enabling part 1 mgross
2020-12-01 22:34 ` [PATCH 01/22] Add Vision Processing Unit (VPU) documentation mgross
2020-12-18 23:30 ` Randy Dunlap
2021-01-07 20:16 ` mark gross
2020-12-01 22:34 ` [PATCH 02/22] dt-bindings: Add bindings for Keem Bay IPC driver mgross
2020-12-07 16:01 ` Rob Herring
2020-12-07 18:22 ` mark gross
2020-12-07 18:42 ` Daniele Alessandrelli
2020-12-07 20:31 ` Jassi Brar
2020-12-09 0:12 ` mark gross
2020-12-09 16:49 ` Jassi Brar
2020-12-09 17:33 ` Rob Herring
2020-12-01 22:34 ` [PATCH 03/22] keembay-ipc: Add Keem Bay IPC module mgross
2020-12-02 6:16 ` Greg KH
2020-12-02 17:42 ` mark gross
2020-12-02 19:01 ` Greg KH
2020-12-05 3:35 ` mark gross
2020-12-05 8:40 ` Greg KH
2020-12-05 16:37 ` Gross, Mark
2020-12-07 1:36 ` mark gross
2020-12-02 6:19 ` Greg KH
2020-12-08 18:59 ` Daniele Alessandrelli
2020-12-08 19:48 ` Greg KH
2020-12-10 18:38 ` Daniele Alessandrelli
2020-12-11 8:22 ` Greg KH
2020-12-11 17:26 ` Gross, Mark
2020-12-01 22:34 ` [PATCH 04/22] dt-bindings: Add bindings for Keem Bay VPU IPC driver mgross
2020-12-07 15:57 ` Rob Herring
2020-12-07 21:28 ` mark gross
2020-12-01 22:34 ` [PATCH 05/22] keembay-vpu-ipc: Add Keem Bay VPU IPC module mgross
2020-12-01 22:34 ` [PATCH 06/22] misc: xlink-pcie: Add documentation for XLink PCIe driver mgross
2020-12-18 22:59 ` Randy Dunlap
2020-12-19 0:07 ` mark gross
2020-12-01 22:34 ` [PATCH 07/22] misc: xlink-pcie: lh: Add PCIe EPF driver for Local Host mgross
2020-12-01 22:34 ` [PATCH 08/22] misc: xlink-pcie: lh: Add PCIe EP DMA functionality mgross
2020-12-01 22:34 ` [PATCH 09/22] misc: xlink-pcie: lh: Add core communication logic mgross
2020-12-02 6:18 ` Greg KH
2020-12-02 16:46 ` Thokala, Srikanth
2020-12-01 22:34 ` [PATCH 10/22] misc: xlink-pcie: lh: Prepare changes for adding remote host driver mgross
2020-12-01 22:35 ` [PATCH 11/22] misc: xlink-pcie: rh: Add PCIe EP driver for Remote Host mgross
2020-12-01 22:35 ` [PATCH 12/22] misc: xlink-pcie: rh: Add core communication logic mgross
2020-12-01 22:35 ` [PATCH 13/22] misc: xlink-pcie: Add XLink API interface mgross
2020-12-01 22:35 ` [PATCH 14/22] misc: xlink-pcie: Add asynchronous event notification support for XLink mgross
2020-12-01 22:35 ` [PATCH 15/22] xlink-ipc: Add xlink ipc device tree bindings mgross
2020-12-07 15:58 ` Rob Herring
2020-12-07 21:41 ` mark gross
2020-12-01 22:35 ` [PATCH 16/22] xlink-ipc: Add xlink ipc driver mgross
2020-12-07 2:32 ` Joe Perches
2020-12-11 11:33 ` Kelly, Seamus
2020-12-11 12:14 ` gregkh
2020-12-11 17:12 ` Gross, Mark
2020-12-07 19:53 ` Randy Dunlap
2020-12-01 22:35 ` [PATCH 17/22] xlink-core: Add xlink core device tree bindings mgross
2020-12-07 16:02 ` Rob Herring
2020-12-01 22:35 ` [PATCH 18/22] xlink-core: Add xlink core driver xLink mgross
2020-12-07 21:50 ` Randy Dunlap
2020-12-01 22:35 ` [PATCH 19/22] xlink-core: Enable xlink protocol over pcie mgross
2020-12-01 22:35 ` [PATCH 20/22] xlink-core: Enable VPU IP management and runtime control mgross
2020-12-01 22:35 ` [PATCH 21/22] xlink-core: add async channel and events mgross
2020-12-07 2:55 ` Joe Perches
2020-12-11 11:34 ` Kelly, Seamus
2020-12-01 22:35 ` [PATCH 22/22] xlink-core: factorize xlink_ioctl function by creating sub-functions for each ioctl command mgross
2020-12-07 3:05 ` Joe Perches
2020-12-07 21:59 ` mark gross
2020-12-09 8:30 ` Joe Perches [this message]
2020-12-11 11:36 ` Kelly, Seamus
-- strict thread matches above, loose matches on Subject: below --
2020-11-30 23:06 [PATCH 00/22] Intel Vision Processing Unit base enabling part 1 mgross
2020-11-30 23:07 ` [PATCH 22/22] xlink-core: factorize xlink_ioctl function by creating sub-functions for each ioctl command mgross
[not found] <20201125184349.29686-1-mgross@linux.intel.com>
[not found] ` <20201125184349.29686-23-mgross@linux.intel.com>
2020-11-26 20:26 ` Greg Kroah-Hartman
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