EmbLogic » Rahul Sharma

PARALLEL PORT -8 led array

Rahul Sharma — Mon, 23 Jun 2014 14:43:58 +0000

Succesfully implemented the parallel port outb operations using 8-led array!!!

I had firstly make a sculldev allocate memory to it so that i can map the file_operations through the
cdev_init and cdev_add operations and then map the parallel port address to the user address,then map the write operation to the driver and i had made a application for sending the data byte from the application through the node to the driver and received by the scull_write function in the map space then get the data from the application to the __user *buffer and then copy_from_user to get the data from application and then save it in the unsigned char buffer and then outb the data to the parallel port and continuously sending the data from the application and sending the data continuously to the port and the binary representation of the characters are shown on the led’s.

implemented ioctl :change quantum and qset using operation

Rahul Sharma — Fri, 13 Jun 2014 11:00:13 +0000

RCS file: ./ioctl.c,v
Working file: ./ioctl.c
head: 1.23
branch:
locks: strict
root: 1.23
access list:
symbolic names:
keyword substitution: kv
total revisions: 23; selected revisions: 23
description:
this is our ioctl.c file for driver operations
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revision 1.23 locked by: root;
date: 2014/06/11 03:22:58; author: root; state: Exp; lines: +6 -1
IOCSQSET applied in case
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revision 1.22
date: 2014/06/08 20:06:07; author: root; state: Exp; lines: +1 -1
working fine for scull_IOCSQUANTUM
able to set the quantum value to 16 or 32 and then write changes in skull and then read the skull properly
working fine till now
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revision 1.21
date: 2014/06/08 05:31:57; author: root; state: Exp; lines: +3 -0
*** empty log message ***
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revision 1.20
date: 2014/06/07 22:09:52; author: root; state: Exp; lines: +3 -6
*** empty log message ***
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revision 1.19
date: 2014/06/07 19:36:41; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.18
date: 2014/06/07 19:20:32; author: root; state: Exp; lines: +2 -1
*** empty log message ***
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revision 1.17
date: 2014/06/07 19:19:11; author: root; state: Exp; lines: +1 -1
*** empty log message ***
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revision 1.16
date: 2014/06/07 19:16:56; author: root; state: Exp; lines: +1 -1
*** empty log message ***
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revision 1.15
date: 2014/06/07 19:16:35; author: root; state: Exp; lines: +3 -3
*** empty log message ***
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revision 1.14
date: 2014/06/07 19:10:41; author: root; state: Exp; lines: +1 -2
*** empty log message ***
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revision 1.13
date: 2014/06/07 19:08:04; author: root; state: Exp; lines: +1 -1
*** empty log message ***
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revision 1.12
date: 2014/06/07 19:07:40; author: root; state: Exp; lines: +5 -5
testing!!!!!!!!!!!!!!!!!
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revision 1.11
date: 2014/06/07 19:00:39; author: root; state: Exp; lines: +6 -5
testing
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revision 1.10
date: 2014/06/07 18:32:34; author: root; state: Exp; lines: +4 -4
working fine for IOCGQUANTUM…….!!!!!!!!!!!!!!!
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revision 1.9
date: 2014/06/07 18:04:09; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.8
date: 2014/06/07 17:51:09; author: root; state: Exp; lines: +3 -2
*** empty log message ***
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revision 1.7
date: 2014/06/07 17:48:12; author: root; state: Exp; lines: +1 -1
*** empty log message ***
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revision 1.6
date: 2014/06/07 17:44:38; author: root; state: Exp; lines: +3 -1
testing!!!!!!!!!!!!!!!!!
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revision 1.5
date: 2014/06/07 17:37:27; author: root; state: Exp; lines: +2 -1
*** empty log message ***
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revision 1.4
date: 2014/06/07 17:34:13; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.3
date: 2014/06/07 17:30:50; author: root; state: Exp; lines: +1 -1
updated ret for case IOCSQUANTUM
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revision 1.2
date: 2014/06/07 17:22:00; author: root; state: Exp; lines: +1 -1
include commands like SCULL_IOCSQUANTUM
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revision 1.1
date: 2014/06/07 17:11:17; author: root; state: Exp;
Initial revision
============================================================================

server-client using threads in server(using aprox all IPC techniques

Rahul Sharma — Tue, 10 Jun 2014 09:52:36 +0000

RCS file: ./server.c,v
Working file: ./server.c
head: 1.5
branch:
locks: strict
root: 1.5
access list:
symbolic names:
keyword substitution: kv
total revisions: 5; selected revisions: 5
description:
this is the server accepting data
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revision 1.5 locked by: root;
date: 2014/06/09 21:07:39; author: root; state: Exp; lines: +192 -95
in this code i am getting the data from the requesting client through the fifo then
giving switch call for the type of operator eg + and then in the case + ,i am calling thread in which i had
use fork and execl to dulplicate the processadd file to calculate the result of the operation and the data is shared to the processadd function to the server via a shared memory
after the data is processed the result is captured by the thread calling processadd and then sending to the respective r_clients through the message queue that are common to all the requesting clients
i had implemented the process level semaphore ,so that only 1 process should aquire the server at one time
the write of the requesting client is in the critical area of the semaphore and the messagequeue is present outside the critical region of the requesting client
WORKING FINE!!!!!!!!!!!!!!
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revision 1.4
date: 2014/05/30 16:28:40; author: root; state: Exp; lines: +128 -3
working succesfully with all the 4 cases if the r_clients enncounterred one by one
if encounterred grouply then error
sollution is attached a while loop in the switch but i am geeting error of segment default
to continued
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revision 1.3
date: 2014/05/30 05:10:01; author: root; state: Exp; lines: +57 -19
As we send th data from the server to processadd we are receiving the data variable res and tag through the
processadd to server via a message queues….
i got a problem here as i mentioned msgget and shmid together i am getting the problem in getting the
value of msg_id and shm_id and it it resolved as i put the msgget just after the shmctl remove the shared memory
WORKING SUCESSFULLY……the data result of add is received to the server
i am sending 10 and 20 from the request1 to server which on behaf of the case ‘+’ send dulplicate the proceess add and send the data through shared memory and the server receive the result through message queues.
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revision 1.2
date: 2014/05/28 15:21:46; author: root; state: Exp; lines: +35 -1
In this server ,we have requesting client 1 ,who sends the data in the form of packet structure
and fifo is connected to it with the server
we send the block of data to the server
block of data contain a,b,tag and oper
oper is checked by the server in the case statement and the data is stored in the structure contain a array of integer
and the we have to send it to the processing client ,processing client have nothing to done with oper
that is send by the requesting client
it it checked within the server
continueeeeee………………………….
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revision 1.1
date: 2014/05/28 15:05:07; author: root; state: Exp;
Initial revision
=============================================================================
*****************************************************************************************************************************************
RCS file: ./r_client1.c,v
Working file: ./r_client1.c
head: 1.1
branch:
locks: strict
root: 1.1
access list:
symbolic names:
keyword substitution: kv
total revisions: 1; selected revisions: 1
description:
this is the file where i am sending th data through the fifo to the server and receiving the data
through message queues and then printing the result
eg this client send 23+ through the fifo to the server
and geeting result 5
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revision 1.1 locked by: root;
date: 2014/06/09 21:06:51; author: root; state: Exp;
Initial revision
*************************************************************************************************************************************

RCS file: ./processadd.c,v
Working file: ./processadd.c
head: 1.4
branch:
locks: strict
root: 1.4
access list:
symbolic names:
keyword substitution: kv
total revisions: 4; selected revisions: 4
description:
this is processadd file
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revision 1.4 locked by: root;
date: 2014/06/09 21:15:02; author: root; state: Exp; lines: +1 -0
IN this file I am getting the data through the shared memory from the server and all the addition calculation
are done in this file
after the thread do fork and execl to the this file it will put the result in the message queue
which is acquired by their respective requesting clients .
WORKING FINE!!!!!!! for 4 req clients
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revision 1.3
date: 2014/05/30 16:30:22; author: root; state: Exp; lines: +2 -9
made all the 4 processing clients and are working properly
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revision 1.2
date: 2014/05/30 05:14:31; author: root; state: Exp; lines: +52 -0
In this the data variable a,b and tag is recive by the processadd via shared memory and after calculating the
add result it will put the resultin res and tag and then send the data back to the server via message queues.
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revision 1.1
date: 2014/05/28 15:07:04; author: root; state: Exp;
Initial revision
=============================================================================

implemented :completion synchronization technique

Rahul Sharma — Wed, 04 Jun 2014 08:26:44 +0000

RCS file: ./write.c,v
3 Working file: ./write.c
4 head: 1.163
5 branch:
6 locks: strict
7 root: 1.163
8 access list:
9 symbolic names:
10 keyword substitution: kv
11 total revisions: 163; selected revisions: 163
12 description:
13 this is the file for user write like operation
14 —————————-
15 revision 1.163 locked by: root;
16 date: 2014/06/03 19:31:57; author: root; state: Exp; lines: +1 -1
17 comment on complete as have to wok on spinlocks now
18 in write operation we have to use only complete to pass the driver to the read opeartion
19 first we ahve to run the read application located in folder:completion then the application will wait for the
20 writer to write and in testing i have used 3 reader appplication
21 which will wait for the data tto input from the node then once we run the writer and the first read will read the data
22 when we run the writer again the second writer will get the data and similarly for 3rd
23 so tthis type of synchnonising technique is used for the reader writer function for some specific use
24 continuing with “””””spinlock”””””
25 —————————-
26 revision 1.162
27 date: 2014/06/03 18:24:34; author: root; state: Exp; lines: +1 -2
28 complete fn synchronization tech

revision 1.42
28 date: 2014/06/03 18:28:52; author: root; state: Exp; lines: +1 -1
29 include declaration.h
30 —————————-
31 revision 1.41
32 date: 2014/06/03 18:24:57; author: root; state: Exp; lines: +2 -0
33 wait_for_complete and complete …..synchronism technique
34 —————————-
35 revision 1.40
36 date: 2014/05/27 17:52:40; author: root; state: Exp; lines: +3 -3
37 *** empty log message ***
38 —————————-
39 revision 1.39
40 date: 2014/05/27 17:27:03; author: root; state: Exp; lines: +1 -1
41 successfully working for seek_set,seek_cur,seek_end
42 —————————-

character driver-seek_SET,SEEK_CUR and SEEK_END working fine for reading

Rahul Sharma — Wed, 28 May 2014 06:23:27 +0000

RCS file: ./read2.c,v
Working file: ./read2.c
head: 1.40
branch:
locks: strict
access list:
symbolic names:
keyword substitution: kv
total revisions: 40; selected revisions: 40
description:
this is working fine with lseek
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revision 1.40
date: 2014/05/27 17:52:40; author: root; state: Exp; lines: +3 -3
*** empty log message ***
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revision 1.39
date: 2014/05/27 17:27:03; author: root; state: Exp; lines: +1 -1
successfully working for seek_set,seek_cur,seek_end
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revision 1.38
date: 2014/05/27 17:23:05; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.37
date: 2014/05/27 17:21:07; author: root; state: Exp; lines: +1 -3
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revision 1.36
date: 2014/05/27 17:07:02; author: root; state: Exp; lines: +2 -2
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revision 1.35
date: 2014/05/27 17:05:21; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.34
date: 2014/05/27 17:02:47; author: root; state: Exp; lines: +1 -0
if(qpos) then lnoq=lnoq+qpos
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revision 1.33
date: 2014/05/27 16:56:01; author: root; state: Exp; lines: +4 -2
applied condition for the quantum=3 for(lv=qpos;lvf_pos
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revision 1.2
date: 2014/05/26 05:52:28; author: root; state: Exp; lines: +2 -2
changing the condition in for loop
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revision 1.1
date: 2014/05/26 05:27:55; author: root; state: Exp;
Initial revision
=============================================================================

Character driver -lseek operation

Rahul Sharma — Tue, 27 May 2014 07:01:17 +0000

ranch:
locks: strict
access list:
symbolic names:
keyword substitution: kv
total revisions: 19; selected revisions: 19
description:
this is working fine with lseek
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revision 1.19
date: 2014/05/26 18:30:46; author: root; state: Exp; lines: +1 -0
working successfully for read operation using lseek
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revision 1.18
date: 2014/05/26 17:57:00; author: root; state: Exp; lines: +1 -1
*** empty log message ***
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revision 1.17
date: 2014/05/26 17:53:58; author: root; state: Exp; lines: +3 -3
*off+=nocsr;
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revision 1.16
date: 2014/05/26 17:48:06; author: root; state: Exp; lines: +4 -4
changing position of the logic earlier
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revision 1.15
date: 2014/05/26 17:44:53; author: root; state: Exp; lines: +1 -1
*** empty log message ***
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revision 1.14
date: 2014/05/26 17:43:03; author: root; state: Exp; lines: +2 -2
rearranging the previous condition
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revision 1.13
date: 2014/05/26 17:40:15; author: root; state: Exp; lines: +8 -2
condition if offset is greater than the data_size
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Character driver-sucessfully working for min 32 distinct user

Rahul Sharma — Tue, 20 May 2014 11:48:28 +0000

The code is working fine for 32 distinct user acessing 2 nodes node0 and node1
ie, 32 user can acess this driver at a time without reporting a bug.
there are 2 operation that i perform for each application
1.write to scull
2.read from scull without closing fd in the same application

As the same application is acessing the driver by different user using node0 and node1
so in write operation the same memory segment is owerwrite by the different user and read viceversa
the starting address of the device is fixed
if we close the fd after write operation then again open the skull in RDONLY mode the old fd was lost and stream got closed and while reading it will read the last written text in the quantum of the skull.

rlog: RCS/write,v: No such file or directory
[root@rahul basic]# rlog ./write.c

RCS file: ./write.c,v
Working file: ./write.c
head: 1.105
branch:
locks: strict
access list:
symbolic names:
keyword substitution: kv
total revisions: 105; selected revisions: 105
description:
this is the file for user write like operation
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revision 1.105
date: 2014/05/19 20:18:45; author: root; state: Exp; lines: +7 -0
printing llseek pointer value and update at th end
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revision 1.104
date: 2014/05/19 19:29:42; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.103
date: 2014/05/19 19:26:32; author: root; state: Exp; lines: +7 -7
quantum and qset different way of accessing
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revision 1.102
date: 2014/05/19 19:06:19; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.101
date: 2014/05/19 19:05:23; author: root; state: Exp; lines: +2 -5
*** empty log message ***
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revision 1.100
date: 2014/05/19 19:04:27; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.99
date: 2014/05/19 19:03:29; author: root; state: Exp; lines: +7 -0
printing quantum_size and qset_size
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revision 1.98
date: 2014/05/19 18:56:11; author: root; state: Exp; lines: +3 -0
*** empty log message ***
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revision 1.97
date: 2014/05/19 18:51:13; author: root; state: Exp; lines: +7 -11
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revision 1.96
date: 2014/05/19 18:41:22; author: root; state: Exp; lines: +1 -0
*** empty log message ***
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revision 1.95
date: 2014/05/19 18:37:49; author: root; state: Exp; lines: +1 -1
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revision 1.94
date: 2014/05/19 18:36:58; author: root; state: Exp; lines: +1 -1
*** empty log message ***
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revision 1.93
date: 2014/05/19 18:35:12; author: root; state: Exp; lines: +1 -1
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revision 1.92
date: 2014/05/19 18:34:24; author: root; state: Exp; lines: +8 -6
*** empty log message ***
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revision 1.91
date: 2014/05/19 18:26:53; author: root; state: Exp; lines: +4 -4
*** empty log message ***
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revision 1.90
date: 2014/05/19 18:24:01; author: root; state: Exp; lines: +0 -1
*** empty log message ***
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revision 1.89
date: 2014/05/19 18:04:33; author: root; state: Exp; lines: +4 -3
reallocation qset_size to qset and quantum_size to quantum
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revision 1.88
date: 2014/05/19 05:45:58; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.87
date: 2014/05/19 05:36:01; author: root; state: Exp; lines: +2 -2
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revision 1.86
date: 2014/05/19 05:33:44; author: root; state: Exp; lines: +2 -2
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revision 1.85
date: 2014/05/19 05:31:13; author: root; state: Exp; lines: +1 -3
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revision 1.84
date: 2014/05/19 05:30:02; author: root; state: Exp; lines: +0 -2
*** empty log message ***
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revision 1.83
date: 2014/05/19 04:19:02; author: root; state: Exp; lines: +1 -1
set location of label loop
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revision 1.82
date: 2014/05/18 19:57:16; author: root; state: Exp; lines: +1 -1
location of label loop changed
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revision 1.81
date: 2014/05/16 12:53:09; author: root; state: Exp; lines: +1 -1
successful working for multiple quantum,multiple QSETS and scullqsets
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revision 1.80
date: 2014/05/16 08:37:31; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.79
date: 2014/05/16 08:35:54; author: root; state: Exp; lines: +2 -2
testing
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revision 1.78
date: 2014/05/16 08:34:38; author: root; state: Exp; lines: +2 -2
*** empty log message ***
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revision 1.77
date: 2014/05/16 08:29:37; author: root; state: Exp; lines: +1 -1
*** empty log message ***
////////////////////////////////////////////////////////////////////////////////////////////////

RCS file: ./header.h,v
Working file: ./header.h
head: 1.65
branch:
locks: strict
access list:
symbolic names:
keyword substitution: kv
total revisions: 65; selected revisions: 65
description:
this is the initial header file
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revision 1.65
date: 2014/05/19 20:18:21; author: root; state: Exp; lines: +1 -0
give prototype of llseek mapped to scullseek
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revision 1.64
date: 2014/05/19 19:27:36; author: root; state: Exp; lines: +2 -2
changing prototypes of allocate_quantum and allocate_qset
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revision 1.63
date: 2014/05/19 19:03:22; author: root; state: Exp; lines: +0 -2
*** empty log message ***
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revision 1.62
date: 2014/05/19 18:59:34; author: root; state: Exp; lines: +1 -1
*** empty log message ***
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revision 1.61
date: 2014/05/19 18:58:52; author: root; state: Exp; lines: +1 -1
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revision 1.60
date: 2014/05/19 18:58:20; author: root; state: Exp; lines: +2 -2
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revision 1.59
date: 2014/05/19 18:56:10; author: root; state: Exp; lines: +3 -3
*** empty log message ***
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revision 1.58
date: 2014/05/19 18:51:12; author: root; state: Exp; lines: +6 -0
*** empty log message ***
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revision 1.57
date: 2014/05/19 18:29:05; author: root; state: Exp; lines: +4 -4
*** empty log message ***
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revision 1.56
date: 2014/05/19 18:04:01; author: root; state: Exp; lines: +0 -15
delete macros QUANTUM_SIZE,QSET_SIZE,DEVICE_SIZE
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revision 1.55
date: 2014/05/13 09:04:02; author: root; state: Exp; lines: +1 -0
included header file for copy_from_user asm-generic/uaccess.h
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revision 1.54
date: 2014/05/12 10:34:53; author: root; state: Exp; lines: +1 -1
allocate_quantum(void)
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revision 1.53
date: 2014/05/12 10:25:01; author: root; state: Exp; lines: +1 -0
included allocate_quantum()
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revision 1.52
date: 2014/05/12 09:56:40; author: root; state: Exp; lines: +1 -0
included allocate skullqset
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revision 1.51
/////////////////////////////////////////////////////////////////////////////////////////////////////////RCS file: ./scullseek.c,v
Working file: ./scullseek.c
head: 1.1
branch:
locks: strict
access list:
symbolic names:
keyword substitution: kv
total revisions: 1; selected revisions: 1
description:
this is the initial file for llseek system call
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revision 1.1
date: 2014/05/19 20:22:58; author: root; state: Exp;
Initial revision
////////////////////////////////////////////////////////////////////////////////////////////////////
RCS file: ./init.c,v
Working file: ./init.c
head: 1.68
branch:
locks: strict
access list:
symbolic names:
keyword substitution: kv
total revisions: 68; selected revisions: 68
description:
this is the initial file contain initialize function
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revision 1.68
date: 2014/05/19 20:18:14; author: root; state: Exp; lines: +2 -1
*** empty log message ***
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revision 1.67
date: 2014/05/19 18:03:18; author: root; state: Exp; lines: +7 -5
module_param qset_size,quantum_size,device_size all set in the sculldev structure.
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revision 1.66
date: 2014/05/19 17:44:58; author: root; state: Exp; lines: +2 -1
using param for n variable
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revision 1.65
date: 2014/05/19 17:35:37; author: root; state: Exp; lines: +2 -2
module_param n
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revision 1.64
date: 2014/05/10 07:09:08; author: root; state: Exp; lines: +4 -4
*** empty log message ***
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revision 1.63
date: 2014/05/10 06:52:55; author: root; state: Exp; lines: +10 -0
allocate parameters of skulldev and assign values to them
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revision 1.62
date: 2014/05/09 09:31:15; author: root; state: Exp; lines: +1 -1
*** empty log message ***
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revision 1.61
date: 2014/05/09 09:28:39; author: root; state: Exp; lines: +2 -1
included read
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revision 1.60
date: 2014/05/08 07:36:24; author: root; state: Exp; lines: +1 -1
struct Sculldev *sculldev to struct ScullDev *sculldev
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revision 1.59
/////////////////////////////////////////////////////////////////////////////////////

FORK() call–kernal point of view

Rahul Sharma — Fri, 16 May 2014 14:35:23 +0000

when the fork system call is invoked the fork is mappped with the clone system call .
the kernel stores the list of processes in circular doubly link list called task list
each element in the task_list is a process descriptor of type struct task_struct which is defined in
->task_struct contain all the information related to the process

->the process descriptor contain the data that described the execution program-openfile,the process address space ,pending signals ,p
->the task_struct contain the parent pid task_struct.

struct task_struct
{
process descriptor
unsigned long state;
int prio;
unsigned long policy;
struct task_struct *parent; //struct task_struct of the parent
struct list_head tasks;
pid_t pid;
} process_descriptor;
the linklist produced by this task_struct consicute the Kernel process table whos first process after booting process is the init pro
kthreadadd function to make more system related processes needed for the operation of the system OS.

struct task_struct was stored at the end of the kernel stack of each process

Linux implements fork() via the clone() system call.This call takes a series of flags that
specify which resources, if any, the parent and child process should share.The
fork(), vfork(), and __clone() library calls all invoke the clone() system call with the
requisite flags.The clone() system call, in turn, calls do_fork().

The bulk of the work in forking is handled by do_fork(), which is defined in
kernel/fork.c.This function calls copy_process() and then starts the process running.
The interesting work is done by copy_process():

1. It calls dup_task_struct(), which creates a new kernel stack, thread_info struc-
ture, and task_struct for the new process.The new values are identical to those of
the current task.At this point, the child and parent process descriptors are identical.

2. It then checks that the new child will not exceed the resource limits on the num-
ber of processes for the current user.

3. The child needs to differentiate itself from its parent.Various members of the
process descriptor are cleared or set to initial values. Members of the process
descriptor not inherited are primarily statistically information.The bulk of the val-
ues in task_struct remain unchanged.

4. The child’s state is set to TASK_UNINTERRUPTIBLE to ensure that it does not yet run.

5.copy_process() calls copy_flags() to update the flags member of the
task_struct.

6. It calls alloc_pid() to assign an available PID to the new task.

7. Depending on the flags passed to clone(), copy_process() either duplicates or
shares open files, filesystem information, signal handlers, process address space, and
namespace.These resources are typically shared between threads in a given process;
otherwise they are unique and thus copied here.

8. Finally, copy_process() cleans up and returns to the caller a pointer to the new
child.
Back in do_fork(), if copy_process() returns successfully, the new child is woken up
and run. Deliberately, the kernel runs the child process first. In the common case of the
child simply calling exec() immediately, this eliminates any copy-on-write overhead that
would occur if the parent ran first and began writing to the address space.

CHARACTER Driver :entered data in multiple scullqsets ,qsets and quantums

Rahul Sharma — Fri, 16 May 2014 13:00:04 +0000

RCS file: write.c,v
Working file: write.c
head: 1.81
branch:
locks: strict
access list:
symbolic names:
keyword substitution: kv
total revisions: 81; selected revisions: 81
description:
this is the file for user write like operation
—————————-
revision 1.81
date: 2014/05/16 12:53:09; author: root; state: Exp; lines: +1 -1
successful working for multiple quantum,multiple QSETS and scullqsets
—————————-
revision 1.80
date: 2014/05/16 08:37:31; author: root; state: Exp; lines: +2 -2
*** empty log message ***
—————————-
revision 1.79
date: 2014/05/16 08:35:54; author: root; state: Exp; lines: +2 -2
testing
—————————-

revision 1.74
date: 2014/05/16 08:19:49; author: root; state: Exp; lines: +2 -2
testing
—————————-
revision 1.73
date: 2014/05/16 08:11:42; author: root; state: Exp; lines: +4 -0
error resolved as no. of quantum are multiple of 8 so it will not come out of the loop
untill 8 quantum complete evn if the noctw next
—————————-

revision 1.60
date: 2014/05/16 05:45:12; author: root; state: Exp; lines: +14 -15
2 scullqset
—————————-
revision 1.59
date: 2014/05/15 18:17:54; author: root; state: Exp; lines: +1 -1
*** empty log message ***
—————————-
revision 1.58
date: 2014/05/15 18:16:35; author: root; state: Exp; lines: +13 -8
multiple scullqset and 2 scullqset
—————————-
revision 1.57
date: 2014/05/15 17:43:02; author: root; state: Exp; lines: +1 -1
print ret value
—————————-
revision 1.56
date: 2014/05/15 10:33:38; author: root; state: Exp; lines: +1 -1
return nocsw from the write function
—————————-
revision 1.55
date: 2014/05/15 10:30:42; author: root; state: Exp; lines: +3 -0
printk the nocsw and noctw
—————————-

revision 1.48
date: 2014/05/15 09:35:00; author: root; state: Exp; lines: +29 -20
enterring no. of quantum in respective qsets
—————————-
revision 1.47
date: 2014/05/13 18:08:24; author: root; state: Exp; lines: +8 -8
*** empty log message ***
—————————-
revision 1.46
date: 2014/05/13 17:33:27; author: root; state: Exp; lines: +1 -1
testing
—————————-
revision 1.45
date: 2014/05/13 17:31:42; author: root; state: Exp; lines: +6 -4
calculation on copy on user
—————————-
revision 1.44
date: 2014/05/13 16:54:48; author: root; state: Exp; lines: +13 -13
corrected copyfromuser
—————————-
revision 1.43
date: 2014/05/13 15:38:39; author: root; state: Exp; lines: +4 -3
*** empty log message ***
—————————-
revision 1.42
date: 2014/05/13 14:43:34; author: root; state: Exp; lines: +2 -2
testing
—————————-
revision 1.41
date: 2014/05/13 14:38:24; author: root; state: Exp; lines: +3 -1
included memset in both the kmalloc used in function
————————–
—————————-
revision 1.29
date: 2014/05/13 09:06:22; author: root; state: Exp; lines: +3 -3
lsize typecast to size
—————————-
revision 1.28
date: 2014/05/13 09:04:28; author: root; state: Exp; lines: +2 -2
type cast the size from the write function
—————————-
revision 1.27
date: 2014/05/13 08:46:18; author: root; state: Exp; lines: +5 -1
use of copy_from

user….copy_from_user(to,from,sizeofbuffer) :
to=lsculldev->data
from =buffer
—————————-
revision 1.26
date: 2014/05/12 10:34:04; author: root; state: Exp; lines: +1 -1
*** empty log message ***
—————————-
revision 1.25
date: 2014/05/12 10:33:06; author: root; state: Exp; lines: +3 -2
included void *p
—————————-
revision 1.24
date: 2014/05/12 10:25:26; author: root; state: Exp; lines: +4 -4
added allocate_quantum
—————————-
revision 1.23
date: 2014/05/12 10:04:53; author: root; state: Exp; lines: +2 -2
*** empty log message ***
—————————-
revision 1.22
date: 2014/05/12 09:56:55; author: root; state: Exp; lines: +7 -7
write allocate_scullqset
—————————-
revision 1.21

revision 1.18
date: 2014/05/12 08:48:04; author: root; state: Exp; lines: +2 -2
remove OUT :
—————————-
revision 1.17
date: 2014/05/12 08:46:33; author: root; state: Exp; lines: +6 -6
chages in create_skull change lsculldev to lscullqset
—————————-
revision 1.16
date: 2014/05/12 08:41:50; author: root; state: Exp; lines: +1 -0
prototype of crete_skull not there
—————————-
revision 1.15
date: 2014/05/12 08:36:44; author: root; state: Exp; lines: +160 -1
in this file i have wrote the scull
first calculate noqset and makwe the required no. of qset and then the quantum in those queset
use 30 bytes of data as a reference to send it to the DD
—————————-

Walkie-talkie chatting operation using message queue in two different process

Rahul Sharma — Fri, 28 Mar 2014 03:50:20 +0000

RCS file: mesg1.c,v
Working file: mesg1.c
head: 1.1
branch:
locks: strict
root: 1.1
access list:
symbolic names:
keyword substitution: kv
total revisions: 1; selected revisions: 1
description:
IN this program work as the walkie talkie half duplex mode….
There are two processes that are communicating through each other through messagequeue
IN walkie talkie there is a HOLD key here there is a (key-swap) ,if we write swap then the processes are swapped
and now the 2nd process becomes the transmitter process and the first process becomes the receiver process
and viceversa you can do it by sending the word(swap) to other process.

SUCCESSFULLY EXECUTED!!!!!!!!!
—————————-
revision 1.1 locked by: root;
date: 2014/03/27 17:57:18; author: root; state: Exp;
Initial revision
=============================================================================

Implemented message queue for 1 child-parent process

Rahul Sharma — Wed, 26 Mar 2014 08:19:53 +0000

RCS file: ./practice.c,v
Working file: ./practice.c
head: 1.2
branch:
locks: strict
root: 1.2
access list:
symbolic names:
keyword substitution: kv
total revisions: 2; selected revisions: 2
description:
initial version of file
in this we have used fork child send 2 message and then receive the data at the parent side
—————————-
revision 1.2 locked by: root;
date: 2014/03/26 08:12:54; author: root; state: Exp; lines: +14 -3
successfully running
send 2 messages to the message queues from the child process and receive the same from the parent process and
display the result of the message ,
i have created 2 instance of the message structure and send hello and world through these instances
and then receive the block of the data from the parent process and display the message and then remove the queue
—————————-
revision 1.1
date: 2014/03/26 07:42:52; author: root; state: Exp;
Initial revision
=============================================================================

Implemented semaphore for 3 clients and sending result to respective client from server

Rahul Sharma — Wed, 26 Mar 2014 07:25:14 +0000

RCS file: ./semaphore.c,v
Working file: ./semaphore.c
head: 1.6
branch:
locks: strict
root: 1.6
access list:
symbolic names:
keyword substitution: kv
total revisions: 6; selected revisions: 6
description:
this is the intial file going to start the SEMAPHORE
—————————-
revision 1.6 locked by: root;
date: 2014/03/25 07:26:08; author: root; state: Exp; lines: +66 -16
successfully implemented 3 clients :1st client gives 23+ as input to server and after processing from the server
server will send the result to the same ist client through result fifo and value is reflected in the client1
after the critical area of client1
viceversa we got the result in 3 different clients
problem is that the irregular output various time as we run the same code
sometime it will take client1 2 times for the addition operation and then the subtract and willnt display for multiple
sometime unpredictable result we get
—————————-
revision 1.5
date: 2014/03/24 10:40:23; author: root; state: Exp; lines: +2 -2
successfully implemented for 3 different clients we have 3 clients client1(rahul),client2(hello),client3(GGOOD)
first of all activate server semaphore.c
tehn run the script containing ./client1,./client2,./client3
for every client server will send the string rebount to noticify that the processing is done
first the client1 send the string and server send back rebound for all the clients but the client get into block on read
—————————-
revision 1.4
date: 2014/03/24 10:11:26; author: root; state: Exp; lines: +5 -5
sending the result ie rebound to client1 and client 1 is reciving the rebound and rebound to client2
—————————-
revision 1.3
date: 2014/03/24 09:13:31; author: root; state: Exp; lines: +28 -13
in this file we have send 2 different values from the 2 different clients to the server and the client that is invoked in the critical region server got the value and display
the server is kept in the while loop to continuous accept the clients value
heading towards the program in while result of the client computing is send back to the same client
—————————-
revision 1.2
date: 2014/03/24 06:24:19; author: root; state: Exp; lines: +37 -10
successfully executed for 1 client file name client2
in this we are writting hello from the server and getting hello from the server through the fifo
heading towards the second client ie client1.c
—————————-
revision 1.1
date: 2014/03/20 10:09:35; author: root; state: Exp;
Initial revision
=============================================================================

MULTIPLE DATA COMPRESSION 3-bit (2 key encryption)

Rahul Sharma — Wed, 19 Mar 2014 19:02:27 +0000

Working file: ./header.h
head: 1.3
branch:
locks: strict
root: 1.3
access list:
symbolic names:
keyword substitution: kv
total revisions: 3; selected revisions: 3
description:
in this file i had compressed the data of 3 bit codelength ie max 8 distinct character using approch
in this i had compressed the data in the chunks of 3 bit in a character ,in 1 character i had placed
3 bits of ist character,3 bits of 2nd character and 2 bits of the 3 chacter and the last bit of the
3rd character is stored in a charcter variable key,so the last bit of every 3rd variable is stored in the this vary char cter variable key
the encryption had become strong as have used masterarray,ndc and this key to decompressed the compressed variable
this concept is due the problem as under
As i have 8 distinct characters so i have to work on every 3bits of each index ,so that the code length increases
but here the code remain simple
—————————-
revision 1.3 locked by: root;
date: 2014/03/19 18:55:27; author: root; state: Exp; lines: +7 -5
problem solved …code working perfectly for 3 bit
—————————-
revision 1.2
date: 2014/03/19 18:36:25; author: root; state: Exp; lines: +9 -3
uncompressed string is hello howarh and the string decompressed is hellowho arh
removing errors

Implemented Queues-push,pop,display,delete

Rahul Sharma — Mon, 10 Mar 2014 18:57:09 +0000

RCS file: queues.c,v
Working file: queues.c
head: 1.2
branch:
locks: strict
access list:
symbolic names:
keyword substitution: kv
total revisions: 2; selected revisions: 2
description:
this is the initial version ,here i have completed the push function operation by passing the

double void**queues from the main
rear value is incremented and the frount value stays at -1 location
—————————-
revision 2.2
date: 2014/03/10 18:50:40; author: root; state: Exp; lines: +34 -13
enterred display function,pop function and then displaying the result as a output
working fine!!
—————————-
revision 1.1
date: 2014/03/10 09:52:57; author: root; state: Exp;
Initial revision
=============================================================================

multiple data compression-decompression 4-bit

Rahul Sharma — Wed, 26 Feb 2014 18:02:45 +0000

RCS file: ./mdcaeuit.c,v
Working file: ./mdcaeuit.c
head: 1.17
branch:
locks: strict
root: 1.17
access list:
logins
symbolic names:
keyword substitution: kv
total revisions: 17; selected revisions: 17
description:
this is the initiated source file have to make ammendment
—————————-
revision 1.17 locked by: root;
date: 2014/02/26 17:58:27; author: root; state: Exp; lines: +12 -12
code working fine with codelength of 4-bit
completed 4-bit compression and decompression
—————————-
revision 1.16
date: 2014/02/22 18:36:03; author: root; state: Exp; lines: +33 -13
logic correction
—————————-
revision 1.15
date: 2014/02/13 07:33:42; author: root; state: Exp; lines: +2 -3
decompression started
decompression function introduced in the program
—————————-
revision 1.14
date: 2014/02/11 18:31:52; author: root; state: Exp; lines: +2 -3
compress_data function made
—————————-
revision 1.13
date: 2014/02/11 14:29:21; author: root; state: Exp; lines: +4 -2
trobleshooting missed my file ie funct.h
—————————-
revision 1.12
date: 2014/02/11 14:05:49; author: root; state: Exp; lines: +2 -2
trobleshooting
—————————-
revision 1.11
date: 2014/02/11 10:02:19; author: root; state: Exp; lines: +11 -6
insert compress_4bit function to compress the dat
we need fd,codel and ndc for this fuction at the time of calling in the main function
to make this function to implement we need to find the index first
—————————-
revision 1.10
date: 2014/02/11 09:04:48; author: root; state: Exp; lines: +4 -3
implement code_length function in function.h and implement the same in main
variable is codel
—————————-
revision 1.9
date: 2014/02/10 20:27:37; author: root; state: Exp; lines: +5 -4
insert the distinct character string using functions
functions :distinct_characters(int,int),marray_create(int)
display() and opening(char*,int)
—————————-
revision 1.8
date: 2014/02/07 17:47:19; author: root; state: Exp; lines: +7 -75
coming to enclose data in function
make marray_create(),opening() and display()
—————————-
revision 1.7
date: 2014/02/07 06:49:21; author: root; state: Exp; lines: +11 -14
logical correction
—————————-
revision 1.6
date: 2014/02/05 16:32:43; author: root; state: Exp; lines: +15 -3
add index and character array to get the array back
—————————-
revision 1.5
date: 2014/02/05 11:00:03; author: root; state: Exp; lines: +2 -2
extra spaces in masterarray removed..
error:remove count and insert i
—————————-
revision 1.4
date: 2014/02/05 10:46:30; author: root; state: Exp; lines: +15 -9
compress data in test.file
adding for loop,for checking whether the string contain repeated characters
display compress string in array.
—————————-
revision 1.3
date: 2014/02/05 09:38:02; author: root; state: Exp; lines: +6 -5
use dynamic memmory allotation of masterarray
getting fine result
—————————-
revision 1.2
date: 2014/02/05 08:35:29; author: root; state: Exp; lines: +26 -10
enterred commandline arguments
remove space at the end of the string
using if else in do while loop
—————————-
revision 1.1
date: 2014/01/20 08:02:46; author: rahul; state: Exp;
Initial revision
=============================================================================