Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [PATCH v6 1/8] fs: introduce kernel_pread_file* support
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Luis Chamberlain <mcgrof@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        David Brown <david.brown@linaro.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Shuah Khan <shuah@kernel.org>, bjorn.andersson@linaro.org,
        Shuah Khan <skhan@linuxfoundation.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Mimi Zohar <zohar@linux.ibm.com>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        linux-fsdevel@vger.kernel.org,
        BCM Kernel Feedback <bcm-kernel-feedback-list@broadcom.com>,
        Olof Johansson <olof@lixom.net>,
        Andrew Morton <akpm@linux-foundation.org>,
        Dan Carpenter <dan.carpenter@oracle.com>,
        Colin Ian King <colin.king@canonical.com>,
        Kees Cook <keescook@chromium.org>,
        Takashi Iwai <tiwai@suse.de>, linux-kselftest@vger.kernel.org,
        Andy Gross <agross@kernel.org>,
        linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org
References: <20200605225959.12424-1-scott.branden@broadcom.com>
 <20200605225959.12424-2-scott.branden@broadcom.com>
 <20200606032011.GM19604@bombadil.infradead.org>
From:   Scott Branden <scott.branden@broadcom.com>
Message-ID: <4ca91507-90a5-1a99-ab19-c6782423e870@broadcom.com>
Date:   Fri, 5 Jun 2020 21:56:57 -0700
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.8.0
MIME-Version: 1.0
In-Reply-To: <20200606032011.GM19604@bombadil.infradead.org>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 8bit
Content-Language: en-US
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Matthew,

On 2020-06-05 8:20 p.m., Matthew Wilcox wrote:
> On Fri, Jun 05, 2020 at 03:59:52PM -0700, Scott Branden wrote:
>> -int kernel_read_file(struct file *file, void **buf, loff_t *size,
>> -		     loff_t max_size, enum kernel_read_file_id id)
>> -{
>> -	loff_t i_size, pos;
>> +int kernel_pread_file(struct file *file, void **buf, loff_t *size,
>> +		      loff_t pos, loff_t max_size,
>> +		      enum kernel_pread_opt opt,
>> +		      enum kernel_read_file_id id)
> What is this 'kernel_pread_opt' foolishness?  Why not just pass in
> ~0UL as max_size if you want the entire file?
That is not how existing kernel_read_file api works - max_size is specified.
I guess not everyone has unlimited memory to read a file on any size.
>
>> -int kernel_read_file_from_path_initns(const char *path, void **buf,
>> -				      loff_t *size, loff_t max_size,
>> -				      enum kernel_read_file_id id)
>> +extern int kernel_pread_file_from_path_initns(const char *path, void **buf,
> extern?  really?  i'm shocked gcc doesn't vomit on that.
A typo.  thanks.  You'll have to ask the compiler gods about your shock.