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Commit 7407b976 authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo
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o n_hdlc: CodingStyle cleanups and removal of old stuff 

- remove include kerneld.h, long gone
- some 80 column reformatting
- removal of typedefs
- c99 style documentation, using the existing function documentation
- add MODULE_AUTHOR
- remove GET_USER, COPY_TO_USER and friends
- remove ssize_t typedef, already in the kernel headers
- remove rw_count_t and rw_ret_t, use simple int and size_t as in the
  tty ops prototypes and avoiding casts for return
- make strings in printk in init/exit module routines __initdata/__exitdata
  saving some bytes after module init and for the case where this driver is
  statically linked in the kernel (__exitdata is trown away)

This makes this driver comply with parts of CodingStyle (more to be done) and
makes it looks more like the rest of the kernel, making it easier to read/debug.

Have been using this modifications with ADSL/syncppp for some time, working well.
parent 4df914aa
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drivers/char/n_hdlc.c
View file @ 7407b976
...@@ -6,7 +6,8 @@ ...@@ -6,7 +6,8 @@
* Microgate and SyncLink are registered trademarks of Microgate Corporation * Microgate and SyncLink are registered trademarks of Microgate Corporation
* *
* Adapted from ppp.c, written by Michael Callahan <callahan@maths.ox.ac.uk>, * Adapted from ppp.c, written by Michael Callahan <callahan@maths.ox.ac.uk>,
* Al Longyear <longyear@netcom.com>, Paul Mackerras <Paul.Mackerras@cs.anu.edu.au> * Al Longyear <longyear@netcom.com>,
* Paul Mackerras <Paul.Mackerras@cs.anu.edu.au>
* *
* Original release 01/11/99 * Original release 01/11/99
* $Id: n_hdlc.c,v 4.8 2003/05/06 21:18:51 paulkf Exp $ * $Id: n_hdlc.c,v 4.8 2003/05/06 21:18:51 paulkf Exp $
...@@ -96,32 +97,19 @@ ...@@ -96,32 +97,19 @@
#include <linux/poll.h> #include <linux/poll.h>
#include <linux/in.h> #include <linux/in.h>
#include <linux/ioctl.h>
#include <linux/slab.h> #include <linux/slab.h>
#include <linux/tty.h> #include <linux/tty.h>
#include <linux/errno.h> #include <linux/errno.h>
#include <linux/string.h> /* used in new tty drivers */ #include <linux/string.h> /* used in new tty drivers */
#include <linux/signal.h> /* used in new tty drivers */ #include <linux/signal.h> /* used in new tty drivers */
#include <linux/if.h>
#include <asm/system.h> #include <asm/system.h>
#include <asm/bitops.h> #include <asm/bitops.h>
#include <asm/termios.h> #include <asm/termios.h>
#include <linux/if.h>
#include <linux/ioctl.h>
#ifdef CONFIG_KERNELD
#include <linux/kerneld.h>
#endif
#define GET_USER(error,value,addr) error = get_user(value,addr)
#define COPY_FROM_USER(error,dest,src,size) error = copy_from_user(dest,src,size) ? -EFAULT : 0
#define PUT_USER(error,value,addr) error = put_user(value,addr)
#define COPY_TO_USER(error,dest,src,size) error = copy_to_user(dest,src,size) ? -EFAULT : 0
#include <asm/uaccess.h> #include <asm/uaccess.h>
typedef ssize_t rw_ret_t;
typedef size_t rw_count_t;
/* /*
* Buffers for individual HDLC frames * Buffers for individual HDLC frames
*/ */
...@@ -130,91 +118,90 @@ typedef size_t rw_count_t; ...@@ -130,91 +118,90 @@ typedef size_t rw_count_t;
#define MAX_RX_BUF_COUNT 60 #define MAX_RX_BUF_COUNT 60
#define DEFAULT_TX_BUF_COUNT 1 #define DEFAULT_TX_BUF_COUNT 1
struct n_hdlc_buf {
typedef struct _n_hdlc_buf struct n_hdlc_buf *link;
{
struct _n_hdlc_buf *link;
int count; int count;
char buf[1]; char buf[1];
} N_HDLC_BUF; };
#define N_HDLC_BUF_SIZE (sizeof(N_HDLC_BUF)+maxframe) #define N_HDLC_BUF_SIZE (sizeof(struct n_hdlc_buf) + maxframe)
typedef struct _n_hdlc_buf_list struct n_hdlc_buf_list {
{ struct n_hdlc_buf *head;
N_HDLC_BUF *head; struct n_hdlc_buf *tail;
N_HDLC_BUF *tail;
int count; int count;
spinlock_t spinlock; spinlock_t spinlock;
};
} N_HDLC_BUF_LIST; /**
* struct n_hdlc - per device instance data structure
/* * @magic - magic value for structure
* Per device instance data structure * @flags - miscellaneous control flags
* @tty - ptr to TTY structure
* @backup_tty - TTY to use if tty gets closed
* @tbusy - reentrancy flag for tx wakeup code
* @woke_up - FIXME: describe this field
* @tbuf - currently transmitting tx buffer
* @tx_buf_list - list of pending transmit frame buffers
* @rx_buf_list - list of received frame buffers
* @tx_free_buf_list - list unused transmit frame buffers
* @rx_free_buf_list - list unused received frame buffers
*/ */
struct n_hdlc { struct n_hdlc {
int magic; /* magic value for structure */ int magic;
__u32 flags; /* miscellaneous control flags */ __u32 flags;
struct tty_struct *tty;
struct tty_struct *tty; /* ptr to TTY structure */ struct tty_struct *backup_tty;
struct tty_struct *backup_tty; /* TTY to use if tty gets closed */ int tbusy;
int tbusy; /* reentrancy flag for tx wakeup code */
int woke_up; int woke_up;
N_HDLC_BUF *tbuf; /* currently transmitting tx buffer */ struct n_hdlc_buf *tbuf;
N_HDLC_BUF_LIST tx_buf_list; /* list of pending transmit frame buffers */ struct n_hdlc_buf_list tx_buf_list;
N_HDLC_BUF_LIST rx_buf_list; /* list of received frame buffers */ struct n_hdlc_buf_list rx_buf_list;
N_HDLC_BUF_LIST tx_free_buf_list; /* list unused transmit frame buffers */ struct n_hdlc_buf_list tx_free_buf_list;
N_HDLC_BUF_LIST rx_free_buf_list; /* list unused received frame buffers */ struct n_hdlc_buf_list rx_free_buf_list;
}; };
/* /*
* HDLC buffer list manipulation functions * HDLC buffer list manipulation functions
*/ */
static void n_hdlc_buf_list_init(N_HDLC_BUF_LIST *list); static void n_hdlc_buf_list_init(struct n_hdlc_buf_list *list);
static void n_hdlc_buf_put(N_HDLC_BUF_LIST *list,N_HDLC_BUF *buf); static void n_hdlc_buf_put(struct n_hdlc_buf_list *list,
static N_HDLC_BUF* n_hdlc_buf_get(N_HDLC_BUF_LIST *list); struct n_hdlc_buf *buf);
static struct n_hdlc_buf *n_hdlc_buf_get(struct n_hdlc_buf_list *list);
/* Local functions */ /* Local functions */
static struct n_hdlc *n_hdlc_alloc (void); static struct n_hdlc *n_hdlc_alloc (void);
MODULE_PARM(debuglevel, "i");
MODULE_PARM(maxframe, "i");
/* debug level can be set by insmod for debugging purposes */ /* debug level can be set by insmod for debugging purposes */
#define DEBUG_LEVEL_INFO 1 #define DEBUG_LEVEL_INFO 1
static int debuglevel; static int debuglevel;
/* max frame size for memory allocations */ /* max frame size for memory allocations */
static ssize_t maxframe=4096; static ssize_t maxframe = 4096;
/* TTY callbacks */ /* TTY callbacks */
static rw_ret_t n_hdlc_tty_read(struct tty_struct *, static int n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
struct file *, __u8 *, rw_count_t); __u8 *buf, size_t nr);
static rw_ret_t n_hdlc_tty_write(struct tty_struct *, static int n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
struct file *, const __u8 *, rw_count_t); const __u8 *buf, size_t nr);
static int n_hdlc_tty_ioctl(struct tty_struct *, static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file,
struct file *, unsigned int, unsigned long); unsigned int cmd, unsigned long arg);
static unsigned int n_hdlc_tty_poll (struct tty_struct *tty, struct file *filp, static unsigned int n_hdlc_tty_poll(struct tty_struct *tty, struct file *filp,
poll_table * wait); poll_table *wait);
static int n_hdlc_tty_open (struct tty_struct *); static int n_hdlc_tty_open(struct tty_struct *tty);
static void n_hdlc_tty_close (struct tty_struct *); static void n_hdlc_tty_close(struct tty_struct *tty);
static int n_hdlc_tty_room (struct tty_struct *tty); static int n_hdlc_tty_room(struct tty_struct *tty);
static void n_hdlc_tty_receive (struct tty_struct *tty, static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *cp,
const __u8 * cp, char *fp, int count); char *fp, int count);
static void n_hdlc_tty_wakeup (struct tty_struct *tty); static void n_hdlc_tty_wakeup(struct tty_struct *tty);
#define bset(p,b) ((p)[(b) >> 5] |= (1 << ((b) & 0x1f))) #define bset(p,b) ((p)[(b) >> 5] |= (1 << ((b) & 0x1f)))
#define tty2n_hdlc(tty) ((struct n_hdlc *) ((tty)->disc_data)) #define tty2n_hdlc(tty) ((struct n_hdlc *) ((tty)->disc_data))
#define n_hdlc2tty(n_hdlc) ((n_hdlc)->tty) #define n_hdlc2tty(n_hdlc) ((n_hdlc)->tty)
/* Define this string only once for all macro invocations */
static char szVersion[] = HDLC_VERSION;
static struct tty_ldisc n_hdlc_ldisc = { static struct tty_ldisc n_hdlc_ldisc = {
.owner = THIS_MODULE, .owner = THIS_MODULE,
.magic = TTY_LDISC_MAGIC, .magic = TTY_LDISC_MAGIC,
...@@ -230,15 +217,14 @@ static struct tty_ldisc n_hdlc_ldisc = { ...@@ -230,15 +217,14 @@ static struct tty_ldisc n_hdlc_ldisc = {
.write_wakeup = n_hdlc_tty_wakeup, .write_wakeup = n_hdlc_tty_wakeup,
}; };
/* n_hdlc_release() /**
* * n_hdlc_release - release an n_hdlc per device line discipline info structure
* release an n_hdlc per device line discipline info structure * @n_hdlc - per device line discipline info structure
*
*/ */
static void n_hdlc_release (struct n_hdlc *n_hdlc) static void n_hdlc_release(struct n_hdlc *n_hdlc)
{ {
struct tty_struct *tty = n_hdlc2tty (n_hdlc); struct tty_struct *tty = n_hdlc2tty (n_hdlc);
N_HDLC_BUF *buf; struct n_hdlc_buf *buf;
if (debuglevel >= DEBUG_LEVEL_INFO) if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_release() called\n",__FILE__,__LINE__); printk("%s(%d)n_hdlc_release() called\n",__FILE__,__LINE__);
...@@ -285,7 +271,9 @@ static void n_hdlc_release (struct n_hdlc *n_hdlc) ...@@ -285,7 +271,9 @@ static void n_hdlc_release (struct n_hdlc *n_hdlc)
} /* end of n_hdlc_release() */ } /* end of n_hdlc_release() */
/* n_hdlc_tty_close() /**
* n_hdlc_tty_close - line discipline close
* @tty - pointer to tty info structure
* *
* Called when the line discipline is changed to something * Called when the line discipline is changed to something
* else, the tty is closed, or the tty detects a hangup. * else, the tty is closed, or the tty detects a hangup.
...@@ -322,12 +310,11 @@ static void n_hdlc_tty_close(struct tty_struct *tty) ...@@ -322,12 +310,11 @@ static void n_hdlc_tty_close(struct tty_struct *tty)
} /* end of n_hdlc_tty_close() */ } /* end of n_hdlc_tty_close() */
/* n_hdlc_tty_open /**
* * n_hdlc_tty_open - called when line discipline changed to n_hdlc
* called when line discipline changed to n_hdlc * @tty - pointer to tty info structure
* *
* Arguments: tty pointer to tty info structure * Returns 0 if success, otherwise error code
* Return Value: 0 if success, otherwise error code
*/ */
static int n_hdlc_tty_open (struct tty_struct *tty) static int n_hdlc_tty_open (struct tty_struct *tty)
{ {
...@@ -373,22 +360,20 @@ static int n_hdlc_tty_open (struct tty_struct *tty) ...@@ -373,22 +360,20 @@ static int n_hdlc_tty_open (struct tty_struct *tty)
} /* end of n_tty_hdlc_open() */ } /* end of n_tty_hdlc_open() */
/* n_hdlc_send_frames() /**
* n_hdlc_send_frames - send frames on pending send buffer list
* @n_hdlc - pointer to ldisc instance data
* @tty - pointer to tty instance data
* *
* send frames on pending send buffer list until the * Send frames on pending send buffer list until the driver does not accept a
* driver does not accept a frame (busy) * frame (busy) this function is called after adding a frame to the send buffer
* this function is called after adding a frame to the * list and by the tty wakeup callback.
* send buffer list and by the tty wakeup callback
*
* Arguments: n_hdlc pointer to ldisc instance data
* tty pointer to tty instance data
* Return Value: None
*/ */
static void n_hdlc_send_frames (struct n_hdlc *n_hdlc, struct tty_struct *tty) static void n_hdlc_send_frames(struct n_hdlc *n_hdlc, struct tty_struct *tty)
{ {
register int actual; register int actual;
unsigned long flags; unsigned long flags;
N_HDLC_BUF *tbuf; struct n_hdlc_buf *tbuf;
if (debuglevel >= DEBUG_LEVEL_INFO) if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_send_frames() called\n",__FILE__,__LINE__); printk("%s(%d)n_hdlc_send_frames() called\n",__FILE__,__LINE__);
...@@ -431,7 +416,7 @@ static void n_hdlc_send_frames (struct n_hdlc *n_hdlc, struct tty_struct *tty) ...@@ -431,7 +416,7 @@ static void n_hdlc_send_frames (struct n_hdlc *n_hdlc, struct tty_struct *tty)
__FILE__,__LINE__,tbuf); __FILE__,__LINE__,tbuf);
/* free current transmit buffer */ /* free current transmit buffer */
n_hdlc_buf_put(&n_hdlc->tx_free_buf_list,tbuf); n_hdlc_buf_put(&n_hdlc->tx_free_buf_list, tbuf);
/* this tx buffer is done */ /* this tx buffer is done */
n_hdlc->tbuf = NULL; n_hdlc->tbuf = NULL;
...@@ -469,17 +454,15 @@ static void n_hdlc_send_frames (struct n_hdlc *n_hdlc, struct tty_struct *tty) ...@@ -469,17 +454,15 @@ static void n_hdlc_send_frames (struct n_hdlc *n_hdlc, struct tty_struct *tty)
} /* end of n_hdlc_send_frames() */ } /* end of n_hdlc_send_frames() */
/* n_hdlc_tty_wakeup() /**
* n_hdlc_tty_wakeup - Callback for transmit wakeup
* @tty - pointer to associated tty instance data
* *
* Callback for transmit wakeup. Called when low level * Called when low level device driver can accept more send data.
* device driver can accept more send data.
*
* Arguments: tty pointer to associated tty instance data
* Return Value: None
*/ */
static void n_hdlc_tty_wakeup (struct tty_struct *tty) static void n_hdlc_tty_wakeup(struct tty_struct *tty)
{ {
struct n_hdlc *n_hdlc = tty2n_hdlc (tty); struct n_hdlc *n_hdlc = tty2n_hdlc(tty);
if (debuglevel >= DEBUG_LEVEL_INFO) if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_tty_wakeup() called\n",__FILE__,__LINE__); printk("%s(%d)n_hdlc_tty_wakeup() called\n",__FILE__,__LINE__);
...@@ -496,16 +479,14 @@ static void n_hdlc_tty_wakeup (struct tty_struct *tty) ...@@ -496,16 +479,14 @@ static void n_hdlc_tty_wakeup (struct tty_struct *tty)
} /* end of n_hdlc_tty_wakeup() */ } /* end of n_hdlc_tty_wakeup() */
/* n_hdlc_tty_room() /**
* * n_hdlc_tty_room - Return the amount of space left in the receiver's buffer
* Callback function from tty driver. Return the amount of * @tty - pointer to associated tty instance data
* space left in the receiver's buffer to decide if remote
* transmitter is to be throttled.
* *
* Arguments: tty pointer to associated tty instance data * Callback function from tty driver. Return the amount of space left in the
* Return Value: number of bytes left in receive buffer * receiver's buffer to decide if remote transmitter is to be throttled.
*/ */
static int n_hdlc_tty_room (struct tty_struct *tty) static int n_hdlc_tty_room(struct tty_struct *tty)
{ {
if (debuglevel >= DEBUG_LEVEL_INFO) if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_tty_room() called\n",__FILE__,__LINE__); printk("%s(%d)n_hdlc_tty_room() called\n",__FILE__,__LINE__);
...@@ -514,23 +495,21 @@ static int n_hdlc_tty_room (struct tty_struct *tty) ...@@ -514,23 +495,21 @@ static int n_hdlc_tty_room (struct tty_struct *tty)
return 65536; return 65536;
} /* end of n_hdlc_tty_root() */ } /* end of n_hdlc_tty_root() */
/* n_hdlc_tty_receive() /**
* n_hdlc_tty_receive - Called by tty driver when receive data is available
* @tty - pointer to tty instance data
* @data - pointer to received data
* @flags - pointer to flags for data
* @count - count of received data in bytes
* *
* Called by tty low level driver when receive data is * Called by tty low level driver when receive data is available. Data is
* available. Data is interpreted as one HDLC frame. * interpreted as one HDLC frame.
*
* Arguments: tty pointer to tty isntance data
* data pointer to received data
* flags pointer to flags for data
* count count of received data in bytes
*
* Return Value: None
*/ */
static void n_hdlc_tty_receive(struct tty_struct *tty, static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data,
const __u8 * data, char *flags, int count) char *flags, int count)
{ {
register struct n_hdlc *n_hdlc = tty2n_hdlc (tty); register struct n_hdlc *n_hdlc = tty2n_hdlc (tty);
register N_HDLC_BUF *buf; register struct n_hdlc_buf *buf;
if (debuglevel >= DEBUG_LEVEL_INFO) if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_tty_receive() called count=%d\n", printk("%s(%d)n_hdlc_tty_receive() called count=%d\n",
...@@ -560,7 +539,7 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, ...@@ -560,7 +539,7 @@ static void n_hdlc_tty_receive(struct tty_struct *tty,
/* no buffers in free list, attempt to allocate another rx buffer */ /* no buffers in free list, attempt to allocate another rx buffer */
/* unless the maximum count has been reached */ /* unless the maximum count has been reached */
if (n_hdlc->rx_buf_list.count < MAX_RX_BUF_COUNT) if (n_hdlc->rx_buf_list.count < MAX_RX_BUF_COUNT)
buf = (N_HDLC_BUF*)kmalloc(N_HDLC_BUF_SIZE,GFP_ATOMIC); buf = kmalloc(N_HDLC_BUF_SIZE, GFP_ATOMIC);
} }
if (!buf) { if (!buf) {
...@@ -575,7 +554,7 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, ...@@ -575,7 +554,7 @@ static void n_hdlc_tty_receive(struct tty_struct *tty,
buf->count=count; buf->count=count;
/* add HDLC buffer to list of received frames */ /* add HDLC buffer to list of received frames */
n_hdlc_buf_put(&n_hdlc->rx_buf_list,buf); n_hdlc_buf_put(&n_hdlc->rx_buf_list, buf);
/* wake up any blocked reads and perform async signalling */ /* wake up any blocked reads and perform async signalling */
wake_up_interruptible (&tty->read_wait); wake_up_interruptible (&tty->read_wait);
...@@ -584,28 +563,22 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, ...@@ -584,28 +563,22 @@ static void n_hdlc_tty_receive(struct tty_struct *tty,
} /* end of n_hdlc_tty_receive() */ } /* end of n_hdlc_tty_receive() */
/* n_hdlc_tty_read() /**
* * n_hdlc_tty_read - Called to retreive one frame of data (if available)
* Called to retreive one frame of data (if available) * @tty - pointer to tty instance data
* * @file - pointer to open file object
* Arguments: * @buf - pointer to returned data buffer
* * @nr - size of returned data buffer
* tty pointer to tty instance data
* file pointer to open file object
* buf pointer to returned data buffer
* nr size of returned data buffer
* *
* Return Value: * Returns the number of bytes returned or error code.
*
* Number of bytes returned or error code
*/ */
static rw_ret_t n_hdlc_tty_read (struct tty_struct *tty, static int n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
struct file *file, __u8 * buf, rw_count_t nr) __u8 *buf, size_t nr)
{ {
struct n_hdlc *n_hdlc = tty2n_hdlc(tty); struct n_hdlc *n_hdlc = tty2n_hdlc(tty);
int error; int error;
rw_ret_t ret; int ret;
N_HDLC_BUF *rbuf; struct n_hdlc_buf *rbuf;
if (debuglevel >= DEBUG_LEVEL_INFO) if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_tty_read() called\n",__FILE__,__LINE__); printk("%s(%d)n_hdlc_tty_read() called\n",__FILE__,__LINE__);
...@@ -644,16 +617,15 @@ static rw_ret_t n_hdlc_tty_read (struct tty_struct *tty, ...@@ -644,16 +617,15 @@ static rw_ret_t n_hdlc_tty_read (struct tty_struct *tty,
return -EINTR; return -EINTR;
} }
if (rbuf->count > nr) { if (rbuf->count > nr)
/* frame too large for caller's buffer (discard frame) */ /* frame too large for caller's buffer (discard frame) */
ret = (rw_ret_t)-EOVERFLOW; ret = -EOVERFLOW;
} else { else {
/* Copy the data to the caller's buffer */ /* Copy the data to the caller's buffer */
COPY_TO_USER(error,buf,rbuf->buf,rbuf->count); if (copy_to_user(buf, rbuf->buf, rbuf->count))
if (error) ret = -EFAULT;
ret = (rw_ret_t)error;
else else
ret = (rw_ret_t)rbuf->count; ret = rbuf->count;
} }
/* return HDLC buffer to free list unless the free list */ /* return HDLC buffer to free list unless the free list */
...@@ -668,24 +640,22 @@ static rw_ret_t n_hdlc_tty_read (struct tty_struct *tty, ...@@ -668,24 +640,22 @@ static rw_ret_t n_hdlc_tty_read (struct tty_struct *tty,
} /* end of n_hdlc_tty_read() */ } /* end of n_hdlc_tty_read() */
/* n_hdlc_tty_write() /**
* * n_hdlc_tty_write - write a single frame of data to device
* write a single frame of data to device * @tty - pointer to associated tty device instance data
* * @file - pointer to file object data
* Arguments: tty pointer to associated tty device instance data * @data - pointer to transmit data (one frame)
* file pointer to file object data * @count - size of transmit frame in bytes
* data pointer to transmit data (one frame)
* count size of transmit frame in bytes
* *
* Return Value: number of bytes written (or error code) * Returns the number of bytes written (or error code).
*/ */
static rw_ret_t n_hdlc_tty_write (struct tty_struct *tty, struct file *file, static int n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
const __u8 * data, rw_count_t count) const __u8 *data, size_t count)
{ {
struct n_hdlc *n_hdlc = tty2n_hdlc (tty); struct n_hdlc *n_hdlc = tty2n_hdlc (tty);
int error = 0; int error = 0;
DECLARE_WAITQUEUE(wait, current); DECLARE_WAITQUEUE(wait, current);
N_HDLC_BUF *tbuf; struct n_hdlc_buf *tbuf;
if (debuglevel >= DEBUG_LEVEL_INFO) if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_tty_write() called count=%d\n", printk("%s(%d)n_hdlc_tty_write() called count=%d\n",
...@@ -735,10 +705,10 @@ static rw_ret_t n_hdlc_tty_write (struct tty_struct *tty, struct file *file, ...@@ -735,10 +705,10 @@ static rw_ret_t n_hdlc_tty_write (struct tty_struct *tty, struct file *file,
if (!error) { if (!error) {
/* Retrieve the user's buffer */ /* Retrieve the user's buffer */
COPY_FROM_USER (error, tbuf->buf, data, count); if (copy_from_user(tbuf->buf, data, count)) {
if (error) {
/* return tx buffer to free list */ /* return tx buffer to free list */
n_hdlc_buf_put(&n_hdlc->tx_free_buf_list,tbuf); n_hdlc_buf_put(&n_hdlc->tx_free_buf_list,tbuf);
error = -EFAULT;
} else { } else {
/* Send the data */ /* Send the data */
tbuf->count = error = count; tbuf->count = error = count;
...@@ -751,20 +721,16 @@ static rw_ret_t n_hdlc_tty_write (struct tty_struct *tty, struct file *file, ...@@ -751,20 +721,16 @@ static rw_ret_t n_hdlc_tty_write (struct tty_struct *tty, struct file *file,
} /* end of n_hdlc_tty_write() */ } /* end of n_hdlc_tty_write() */
/* n_hdlc_tty_ioctl() /**
* n_hdlc_tty_ioctl - process IOCTL system call for the tty device.
* @tty - pointer to tty instance data
* @file - pointer to open file object for device
* @cmd - IOCTL command code
* @arg - argument for IOCTL call (cmd dependent)
* *
* Process IOCTL system call for the tty device. * Returns command dependent result.
*
* Arguments:
*
* tty pointer to tty instance data
* file pointer to open file object for device
* cmd IOCTL command code
* arg argument for IOCTL call (cmd dependent)
*
* Return Value: Command dependent
*/ */
static int n_hdlc_tty_ioctl (struct tty_struct *tty, struct file * file, static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg) unsigned int cmd, unsigned long arg)
{ {
struct n_hdlc *n_hdlc = tty2n_hdlc (tty); struct n_hdlc *n_hdlc = tty2n_hdlc (tty);
...@@ -790,7 +756,7 @@ static int n_hdlc_tty_ioctl (struct tty_struct *tty, struct file * file, ...@@ -790,7 +756,7 @@ static int n_hdlc_tty_ioctl (struct tty_struct *tty, struct file * file,
else else
count = 0; count = 0;
spin_unlock_irqrestore(&n_hdlc->rx_buf_list.spinlock,flags); spin_unlock_irqrestore(&n_hdlc->rx_buf_list.spinlock,flags);
PUT_USER (error, count, (int *) arg); error = put_user(count, (int *)arg);
break; break;
case TIOCOUTQ: case TIOCOUTQ:
...@@ -802,7 +768,7 @@ static int n_hdlc_tty_ioctl (struct tty_struct *tty, struct file * file, ...@@ -802,7 +768,7 @@ static int n_hdlc_tty_ioctl (struct tty_struct *tty, struct file * file,
if (n_hdlc->tx_buf_list.head) if (n_hdlc->tx_buf_list.head)
count += n_hdlc->tx_buf_list.head->count; count += n_hdlc->tx_buf_list.head->count;
spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock,flags); spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock,flags);
PUT_USER (error, count, (int*)arg); error = put_user(count, (int*)arg);
break; break;
default: default:
...@@ -813,24 +779,18 @@ static int n_hdlc_tty_ioctl (struct tty_struct *tty, struct file * file, ...@@ -813,24 +779,18 @@ static int n_hdlc_tty_ioctl (struct tty_struct *tty, struct file * file,
} /* end of n_hdlc_tty_ioctl() */ } /* end of n_hdlc_tty_ioctl() */
/* n_hdlc_tty_poll() /**
* * n_hdlc_tty_poll - TTY callback for poll system call
* TTY callback for poll system call. Determine which * @tty - pointer to tty instance data
* operations (read/write) will not block and return * @filp - pointer to open file object for device
* info to caller. * @poll_table - wait queue for operations
* *
* Arguments: * Determine which operations (read/write) will not block and return info
* * to caller.
* tty pointer to tty instance data * Returns a bit mask containing info on which ops will not block.
* filp pointer to open file object for device
* poll_table wait queue for operations
*
* Return Value:
*
* bit mask containing info on which ops will not block
*/ */
static unsigned int n_hdlc_tty_poll (struct tty_struct *tty, static unsigned int n_hdlc_tty_poll(struct tty_struct *tty, struct file *filp,
struct file *filp, poll_table * wait) poll_table *wait)
{ {
struct n_hdlc *n_hdlc = tty2n_hdlc (tty); struct n_hdlc *n_hdlc = tty2n_hdlc (tty);
unsigned int mask = 0; unsigned int mask = 0;
...@@ -858,20 +818,17 @@ static unsigned int n_hdlc_tty_poll (struct tty_struct *tty, ...@@ -858,20 +818,17 @@ static unsigned int n_hdlc_tty_poll (struct tty_struct *tty,
return mask; return mask;
} /* end of n_hdlc_tty_poll() */ } /* end of n_hdlc_tty_poll() */
/* n_hdlc_alloc() /**
* * n_hdlc_alloc - allocate an n_hdlc instance data structure
* Allocate an n_hdlc instance data structure
* *
* Arguments: None * Returns a pointer to newly created structure if success, otherwise %NULL
* Return Value: pointer to structure if success, otherwise 0
*/ */
static struct n_hdlc *n_hdlc_alloc (void) static struct n_hdlc *n_hdlc_alloc(void)
{ {
struct n_hdlc *n_hdlc; struct n_hdlc_buf *buf;
N_HDLC_BUF *buf;
int i; int i;
struct n_hdlc *n_hdlc = kmalloc(sizeof(*n_hdlc), GFP_KERNEL);
n_hdlc = (struct n_hdlc *)kmalloc(sizeof(struct n_hdlc), GFP_KERNEL);
if (!n_hdlc) if (!n_hdlc)
return 0; return 0;
...@@ -884,7 +841,7 @@ static struct n_hdlc *n_hdlc_alloc (void) ...@@ -884,7 +841,7 @@ static struct n_hdlc *n_hdlc_alloc (void)
/* allocate free rx buffer list */ /* allocate free rx buffer list */
for(i=0;i<DEFAULT_RX_BUF_COUNT;i++) { for(i=0;i<DEFAULT_RX_BUF_COUNT;i++) {
buf = (N_HDLC_BUF*)kmalloc(N_HDLC_BUF_SIZE,GFP_KERNEL); buf = kmalloc(N_HDLC_BUF_SIZE, GFP_KERNEL);
if (buf) if (buf)
n_hdlc_buf_put(&n_hdlc->rx_free_buf_list,buf); n_hdlc_buf_put(&n_hdlc->rx_free_buf_list,buf);
else if (debuglevel >= DEBUG_LEVEL_INFO) else if (debuglevel >= DEBUG_LEVEL_INFO)
...@@ -893,7 +850,7 @@ static struct n_hdlc *n_hdlc_alloc (void) ...@@ -893,7 +850,7 @@ static struct n_hdlc *n_hdlc_alloc (void)
/* allocate free tx buffer list */ /* allocate free tx buffer list */
for(i=0;i<DEFAULT_TX_BUF_COUNT;i++) { for(i=0;i<DEFAULT_TX_BUF_COUNT;i++) {
buf = (N_HDLC_BUF*)kmalloc(N_HDLC_BUF_SIZE,GFP_KERNEL); buf = kmalloc(N_HDLC_BUF_SIZE, GFP_KERNEL);
if (buf) if (buf)
n_hdlc_buf_put(&n_hdlc->tx_free_buf_list,buf); n_hdlc_buf_put(&n_hdlc->tx_free_buf_list,buf);
else if (debuglevel >= DEBUG_LEVEL_INFO) else if (debuglevel >= DEBUG_LEVEL_INFO)
...@@ -908,31 +865,23 @@ static struct n_hdlc *n_hdlc_alloc (void) ...@@ -908,31 +865,23 @@ static struct n_hdlc *n_hdlc_alloc (void)
} /* end of n_hdlc_alloc() */ } /* end of n_hdlc_alloc() */
/* n_hdlc_buf_list_init() /**
* * n_hdlc_buf_list_init - initialize specified HDLC buffer list
* initialize specified HDLC buffer list * @list - pointer to buffer list
*
* Arguments: list pointer to buffer list
* Return Value: None
*/ */
static void n_hdlc_buf_list_init(N_HDLC_BUF_LIST *list) static void n_hdlc_buf_list_init(struct n_hdlc_buf_list *list)
{ {
memset(list,0,sizeof(N_HDLC_BUF_LIST)); memset(list, 0, sizeof(*list));
spin_lock_init(&list->spinlock); spin_lock_init(&list->spinlock);
} /* end of n_hdlc_buf_list_init() */ } /* end of n_hdlc_buf_list_init() */
/* n_hdlc_buf_put() /**
* * n_hdlc_buf_put - add specified HDLC buffer to tail of specified list
* add specified HDLC buffer to tail of specified list * @list - pointer to buffer list
* * @buf - pointer to buffer
* Arguments:
*
* list pointer to buffer list
* buf pointer to buffer
*
* Return Value: None
*/ */
static void n_hdlc_buf_put(N_HDLC_BUF_LIST *list,N_HDLC_BUF *buf) static void n_hdlc_buf_put(struct n_hdlc_buf_list *list,
struct n_hdlc_buf *buf)
{ {
unsigned long flags; unsigned long flags;
spin_lock_irqsave(&list->spinlock,flags); spin_lock_irqsave(&list->spinlock,flags);
...@@ -949,23 +898,18 @@ static void n_hdlc_buf_put(N_HDLC_BUF_LIST *list,N_HDLC_BUF *buf) ...@@ -949,23 +898,18 @@ static void n_hdlc_buf_put(N_HDLC_BUF_LIST *list,N_HDLC_BUF *buf)
} /* end of n_hdlc_buf_put() */ } /* end of n_hdlc_buf_put() */
/* n_hdlc_buf_get() /**
* * n_hdlc_buf_get - remove and return an HDLC buffer from list
* remove and return an HDLC buffer from the * @list - pointer to HDLC buffer list
* head of the specified HDLC buffer list
*
* Arguments:
*
* list pointer to HDLC buffer list
* *
* Return Value: * Remove and return an HDLC buffer from the head of the specified HDLC buffer
* * list.
* pointer to HDLC buffer if available, otherwise NULL * Returns a pointer to HDLC buffer if available, otherwise %NULL.
*/ */
static N_HDLC_BUF* n_hdlc_buf_get(N_HDLC_BUF_LIST *list) static struct n_hdlc_buf* n_hdlc_buf_get(struct n_hdlc_buf_list *list)
{ {
unsigned long flags; unsigned long flags;
N_HDLC_BUF *buf; struct n_hdlc_buf *buf;
spin_lock_irqsave(&list->spinlock,flags); spin_lock_irqsave(&list->spinlock,flags);
buf = list->head; buf = list->head;
...@@ -981,42 +925,60 @@ static N_HDLC_BUF* n_hdlc_buf_get(N_HDLC_BUF_LIST *list) ...@@ -981,42 +925,60 @@ static N_HDLC_BUF* n_hdlc_buf_get(N_HDLC_BUF_LIST *list)
} /* end of n_hdlc_buf_get() */ } /* end of n_hdlc_buf_get() */
static char hdlc_banner[] __initdata =
KERN_INFO "HDLC line discipline: version " HDLC_VERSION
", maxframe=%u\n";
static char hdlc_register_ok[] __initdata =
KERN_INFO "N_HDLC line discipline registered.\n";
static char hdlc_register_fail[] __initdata =
KERN_ERR "error registering line discipline: %d\n";
static char hdlc_init_fail[] __initdata =
KERN_INFO "N_HDLC: init failure %d\n";
static int __init n_hdlc_init(void) static int __init n_hdlc_init(void)
{ {
int status; int status;
/* range check maxframe arg */ /* range check maxframe arg */
if ( maxframe<4096) if (maxframe < 4096)
maxframe=4096; maxframe = 4096;
else if ( maxframe>65535) else if (maxframe > 65535)
maxframe=65535; maxframe = 65535;
printk("HDLC line discipline: version %s, maxframe=%u\n", printk(hdlc_banner, maxframe);
szVersion, maxframe);
status = tty_register_ldisc(N_HDLC, &n_hdlc_ldisc); status = tty_register_ldisc(N_HDLC, &n_hdlc_ldisc);
if (!status) if (!status)
printk (KERN_INFO"N_HDLC line discipline registered.\n"); printk(hdlc_register_ok);
else else
printk (KERN_ERR"error registering line discipline: %d\n",status); printk(hdlc_register_fail, status);
if (status) if (status)
printk(KERN_INFO"N_HDLC: init failure %d\n", status); printk(hdlc_init_fail, status);
return (status); return status;
} /* end of init_module() */ } /* end of init_module() */
static char hdlc_unregister_ok[] __exitdata =
KERN_INFO "N_HDLC: line discipline unregistered\n";
static char hdlc_unregister_fail[] __exitdata =
KERN_ERR "N_HDLC: can't unregister line discipline (err = %d)\n";
static void __exit n_hdlc_exit(void) static void __exit n_hdlc_exit(void)
{ {
int status;
/* Release tty registration of line discipline */ /* Release tty registration of line discipline */
if ((status = tty_register_ldisc(N_HDLC, NULL))) int status = tty_register_ldisc(N_HDLC, NULL);
printk("N_HDLC: can't unregister line discipline (err = %d)\n", status);
if (status)
printk(hdlc_unregister_fail, status);
else else
printk("N_HDLC: line discipline unregistered\n"); printk(hdlc_unregister_ok);
} }
module_init(n_hdlc_init); module_init(n_hdlc_init);
module_exit(n_hdlc_exit); module_exit(n_hdlc_exit);
MODULE_LICENSE("GPL"); MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul Fulghum paulkf@microgate.com");
MODULE_PARM(debuglevel, "i");
MODULE_PARM(maxframe, "i");
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