Hi Sahil
On Fri, Mar 20, 2015 at 6:12 PM, sahil aggarwal sahil.ag...@gmail.com wrote:
Hi Pranay,
Can you help me with this too.? In case of _IOC_READ why VERIFY_WRITE
and in case of _IOC_WRITE why VERIFY_READ.? . Book says its kernel
oriented so concept of read and write is reversed.
Hi Sahil
On Fri, Mar 20, 2015 at 6:14 PM, sahil aggarwal sahil.ag...@gmail.com wrote:
Does it mean that in kernel space the direction bitfields are reversed.?
No it doesn't mean that.
On 20 March 2015 at 18:12, sahil aggarwal sahil.ag...@gmail.com wrote:
Hi Pranay,
Can you help me with
Hi Pranay
Thanks a lot. That cleared it all.
On 21 March 2015 at 13:45, Pranay Srivastava pran...@gmail.com wrote:
Hi Sahil
On Fri, Mar 20, 2015 at 6:14 PM, sahil aggarwal sahil.ag...@gmail.com wrote:
Does it mean that in kernel space the direction bitfields are reversed.?
No it doesn't
Hi Sahil
On Sun, Mar 15, 2015 at 10:17 AM, sahil aggarwal sahil.ag...@gmail.com wrote:
hi all,
Going through scull driver code, i see read function reads only till
end of 1 quantum, so do kernel call read multiple times if count from
q_pos exceeds quantum size limit.?
Ref: ldd3.
Hi Pranay
Well explained.
Thank you.
On 20 March 2015 at 11:46, Pranay Srivastava pran...@gmail.com wrote:
Hi Sahil
On Sun, Mar 15, 2015 at 10:17 AM, sahil aggarwal sahil.ag...@gmail.com
wrote:
hi all,
Going through scull driver code, i see read function reads only till
end of 1
Hi Pranay,
Can you help me with this too.? In case of _IOC_READ why VERIFY_WRITE
and in case of _IOC_WRITE why VERIFY_READ.? . Book says its kernel
oriented so concept of read and write is reversed.
if(_IOC_DIR(cmd) _IOC_READ)
err = !access_ok(VERIFY_WRITE, (void __user*)arg,
Does it mean that in kernel space the direction bitfields are reversed.?
On 20 March 2015 at 18:12, sahil aggarwal sahil.ag...@gmail.com wrote:
Hi Pranay,
Can you help me with this too.? In case of _IOC_READ why VERIFY_WRITE
and in case of _IOC_WRITE why VERIFY_READ.? . Book says its kernel
hi all,
Going through scull driver code, i see read function reads only till
end of 1 quantum, so do kernel call read multiple times if count from
q_pos exceeds quantum size limit.?
Ref: ldd3.
if(count quantum - q_pos)
count = quantum - q_pos;
if(copy_to_user(buf, dptr-data[s_pos] +
