[PATCH] USB: convert the semaphores in the sisusb driver to mutexes

From: Arjan van de Ven <arjan@infradead.org>

Convert the semaphores-used-as-mutex to mutexes in the sisusb video driver;
this required manual checking due to the "return as locked" stuff in this
driver, but the ->lock semaphore is still used as mutex in the end.

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Cc: Thomas Winischhofer <winischhofer.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Arjan van de Ven 2006-03-28 01:00:21 -08:00 committed by Greg Kroah-Hartman
parent 7327413c74
commit 2682d27c58
3 changed files with 107 additions and 105 deletions

View File

@ -37,6 +37,7 @@
*/
#include <linux/config.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/signal.h>
@ -102,7 +103,7 @@ MODULE_PARM_DESC(last, "Number of last console to take over (1 - MAX_NR_CONSOLES
static struct usb_driver sisusb_driver;
DECLARE_MUTEX(disconnect_sem);
DEFINE_MUTEX(disconnect_mutex);
static void
sisusb_free_buffers(struct sisusb_usb_data *sisusb)
@ -2552,39 +2553,39 @@ sisusb_open(struct inode *inode, struct file *file)
struct usb_interface *interface;
int subminor = iminor(inode);
down(&disconnect_sem);
mutex_lock(&disconnect_mutex);
if (!(interface = usb_find_interface(&sisusb_driver, subminor))) {
printk(KERN_ERR "sisusb[%d]: Failed to find interface\n",
subminor);
up(&disconnect_sem);
mutex_unlock(&disconnect_mutex);
return -ENODEV;
}
if (!(sisusb = usb_get_intfdata(interface))) {
up(&disconnect_sem);
mutex_unlock(&disconnect_mutex);
return -ENODEV;
}
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
if (!sisusb->present || !sisusb->ready) {
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
return -ENODEV;
}
if (sisusb->isopen) {
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
return -EBUSY;
}
if (!sisusb->devinit) {
if (sisusb->sisusb_dev->speed == USB_SPEED_HIGH) {
if (sisusb_init_gfxdevice(sisusb, 0)) {
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
printk(KERN_ERR
"sisusbvga[%d]: Failed to initialize "
"device\n",
@ -2592,8 +2593,8 @@ sisusb_open(struct inode *inode, struct file *file)
return -EIO;
}
} else {
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
printk(KERN_ERR
"sisusbvga[%d]: Device not attached to "
"USB 2.0 hub\n",
@ -2609,9 +2610,9 @@ sisusb_open(struct inode *inode, struct file *file)
file->private_data = sisusb;
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&disconnect_mutex);
return 0;
}
@ -2642,14 +2643,14 @@ sisusb_release(struct inode *inode, struct file *file)
struct sisusb_usb_data *sisusb;
int myminor;
down(&disconnect_sem);
mutex_lock(&disconnect_mutex);
if (!(sisusb = (struct sisusb_usb_data *)file->private_data)) {
up(&disconnect_sem);
mutex_unlock(&disconnect_mutex);
return -ENODEV;
}
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
if (sisusb->present) {
/* Wait for all URBs to finish if device still present */
@ -2662,12 +2663,12 @@ sisusb_release(struct inode *inode, struct file *file)
sisusb->isopen = 0;
file->private_data = NULL;
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
/* decrement the usage count on our device */
kref_put(&sisusb->kref, sisusb_delete);
up(&disconnect_sem);
mutex_unlock(&disconnect_mutex);
return 0;
}
@ -2685,11 +2686,11 @@ sisusb_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
if (!(sisusb = (struct sisusb_usb_data *)file->private_data))
return -ENODEV;
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
/* Sanity check */
if (!sisusb->present || !sisusb->ready || !sisusb->sisusb_dev) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return -ENODEV;
}
@ -2784,7 +2785,7 @@ sisusb_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
(*ppos) <= SISUSB_PCI_PSEUDO_PCIBASE + 0x5c) {
if (count != 4) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return -EINVAL;
}
@ -2808,7 +2809,7 @@ sisusb_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
(*ppos) += bytes_read;
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return errno ? errno : bytes_read;
}
@ -2827,11 +2828,11 @@ sisusb_write(struct file *file, const char __user *buffer, size_t count,
if (!(sisusb = (struct sisusb_usb_data *)file->private_data))
return -ENODEV;
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
/* Sanity check */
if (!sisusb->present || !sisusb->ready || !sisusb->sisusb_dev) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return -ENODEV;
}
@ -2930,7 +2931,7 @@ sisusb_write(struct file *file, const char __user *buffer, size_t count,
(*ppos) <= SISUSB_PCI_PSEUDO_PCIBASE + SISUSB_PCI_PCONFSIZE) {
if (count != 4) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return -EINVAL;
}
@ -2956,7 +2957,7 @@ sisusb_write(struct file *file, const char __user *buffer, size_t count,
(*ppos) += bytes_written;
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return errno ? errno : bytes_written;
}
@ -2970,11 +2971,11 @@ sisusb_lseek(struct file *file, loff_t offset, int orig)
if (!(sisusb = (struct sisusb_usb_data *)file->private_data))
return -ENODEV;
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
/* Sanity check */
if (!sisusb->present || !sisusb->ready || !sisusb->sisusb_dev) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return -ENODEV;
}
@ -2994,7 +2995,7 @@ sisusb_lseek(struct file *file, loff_t offset, int orig)
ret = -EINVAL;
}
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return ret;
}
@ -3136,7 +3137,7 @@ sisusb_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
if (!(sisusb = (struct sisusb_usb_data *)file->private_data))
return -ENODEV;
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
/* Sanity check */
if (!sisusb->present || !sisusb->ready || !sisusb->sisusb_dev) {
@ -3193,7 +3194,7 @@ sisusb_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
}
err_out:
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return retval;
}
@ -3258,7 +3259,7 @@ static int sisusb_probe(struct usb_interface *intf,
}
kref_init(&sisusb->kref);
init_MUTEX(&(sisusb->lock));
mutex_init(&(sisusb->lock));
/* Register device */
if ((retval = usb_register_dev(intf, &usb_sisusb_class))) {
@ -3429,9 +3430,9 @@ static void sisusb_disconnect(struct usb_interface *intf)
* protect all other routines from the disconnect
* case, not the other way round.
*/
down(&disconnect_sem);
mutex_lock(&disconnect_mutex);
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
/* Wait for all URBs to complete and kill them in case (MUST do) */
if (!sisusb_wait_all_out_complete(sisusb))
@ -3462,12 +3463,12 @@ static void sisusb_disconnect(struct usb_interface *intf)
sisusb->present = 0;
sisusb->ready = 0;
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
/* decrement our usage count */
kref_put(&sisusb->kref, sisusb_delete);
up(&disconnect_sem);
mutex_unlock(&disconnect_mutex);
printk(KERN_INFO "sisusbvga[%d]: Disconnected\n", minor);
}

View File

@ -41,6 +41,8 @@
#define SISUSB_NEW_CONFIG_COMPAT
#endif
#include <linux/mutex.h>
/* For older kernels, support for text consoles is by default
* off. To ensable text console support, change the following:
*/
@ -60,11 +62,9 @@
#define INCL_SISUSB_CON 1
#endif
#ifdef INCL_SISUSB_CON
#include <linux/console.h>
#include <linux/vt_kern.h>
#include "sisusb_struct.h"
#endif
/* USB related */
@ -116,7 +116,7 @@ struct sisusb_usb_data {
struct usb_interface *interface;
struct kref kref;
wait_queue_head_t wait_q; /* for syncind and timeouts */
struct semaphore lock; /* general race avoidance */
struct mutex lock; /* general race avoidance */
unsigned int ifnum; /* interface number of the USB device */
int minor; /* minor (for logging clarity) */
int isopen; /* !=0 if open */

View File

@ -48,6 +48,7 @@
*/
#include <linux/config.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/signal.h>
@ -102,7 +103,7 @@ static struct sisusb_usb_data *mysisusbs[MAX_NR_CONSOLES];
/* Forward declaration */
static const struct consw sisusb_con;
extern struct semaphore disconnect_sem;
extern struct mutex disconnect_mutex;
static inline void
sisusbcon_memsetw(u16 *s, u16 c, unsigned int count)
@ -194,11 +195,11 @@ sisusb_get_sisusb_lock_and_check(unsigned short console)
if (!(sisusb = sisusb_get_sisusb(console)))
return NULL;
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
if (!sisusb_sisusb_valid(sisusb) ||
!sisusb->havethisconsole[console]) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return NULL;
}
@ -236,18 +237,18 @@ sisusbcon_init(struct vc_data *c, int init)
* are set up/restored.
*/
down(&disconnect_sem);
mutex_lock(&disconnect_mutex);
if (!(sisusb = sisusb_get_sisusb(c->vc_num))) {
up(&disconnect_sem);
mutex_unlock(&disconnect_mutex);
return;
}
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
if (!sisusb_sisusb_valid(sisusb)) {
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
return;
}
@ -284,9 +285,9 @@ sisusbcon_init(struct vc_data *c, int init)
if (!*c->vc_uni_pagedir_loc)
con_set_default_unimap(c);
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&disconnect_mutex);
if (init) {
c->vc_cols = cols;
@ -306,14 +307,14 @@ sisusbcon_deinit(struct vc_data *c)
* and others, ie not under our control.
*/
down(&disconnect_sem);
mutex_lock(&disconnect_mutex);
if (!(sisusb = sisusb_get_sisusb(c->vc_num))) {
up(&disconnect_sem);
mutex_unlock(&disconnect_mutex);
return;
}
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
/* Clear ourselves in mysisusbs */
mysisusbs[c->vc_num] = NULL;
@ -332,12 +333,12 @@ sisusbcon_deinit(struct vc_data *c)
}
}
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
/* decrement the usage count on our sisusb */
kref_put(&sisusb->kref, sisusb_delete);
up(&disconnect_sem);
mutex_unlock(&disconnect_mutex);
}
/* interface routine */
@ -417,7 +418,7 @@ sisusbcon_putc(struct vc_data *c, int ch, int y, int x)
#endif
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return;
}
@ -425,7 +426,7 @@ sisusbcon_putc(struct vc_data *c, int ch, int y, int x)
sisusb_copy_memory(sisusb, (char *)SISUSB_VADDR(x, y),
(u32)SISUSB_HADDR(x, y), 2, &written);
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
}
/* Interface routine */
@ -453,14 +454,14 @@ sisusbcon_putcs(struct vc_data *c, const unsigned short *s,
sisusbcon_writew(sisusbcon_readw(s++), dest++);
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return;
}
sisusb_copy_memory(sisusb, (char *)SISUSB_VADDR(x, y),
(u32)SISUSB_HADDR(x, y), count * 2, &written);
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
}
/* Interface routine */
@ -504,7 +505,7 @@ sisusbcon_clear(struct vc_data *c, int y, int x, int height, int width)
}
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return;
}
@ -514,7 +515,7 @@ sisusbcon_clear(struct vc_data *c, int y, int x, int height, int width)
sisusb_copy_memory(sisusb, (unsigned char *)SISUSB_VADDR(x, y),
(u32)SISUSB_HADDR(x, y), length, &written);
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
}
/* Interface routine */
@ -576,7 +577,7 @@ sisusbcon_bmove(struct vc_data *c, int sy, int sx,
#endif
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return;
}
@ -586,7 +587,7 @@ sisusbcon_bmove(struct vc_data *c, int sy, int sx,
sisusb_copy_memory(sisusb, (unsigned char *)SISUSB_VADDR(dx, dy),
(u32)SISUSB_HADDR(dx, dy), length, &written);
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
}
/* interface routine */
@ -609,7 +610,7 @@ sisusbcon_switch(struct vc_data *c)
/* Don't write to screen if in gfx mode */
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 0;
}
@ -618,7 +619,7 @@ sisusbcon_switch(struct vc_data *c)
* as origin.
*/
if (c->vc_origin == (unsigned long)c->vc_screenbuf) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
printk(KERN_DEBUG "sisusb: ASSERT ORIGIN != SCREENBUF!\n");
return 0;
}
@ -635,7 +636,7 @@ sisusbcon_switch(struct vc_data *c)
(u32)SISUSB_HADDR(0, 0),
length, &written);
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 0;
}
@ -657,7 +658,7 @@ sisusbcon_save_screen(struct vc_data *c)
/* sisusb->lock is down */
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return;
}
@ -669,7 +670,7 @@ sisusbcon_save_screen(struct vc_data *c)
sisusbcon_memcpyw((u16 *)c->vc_screenbuf, (u16 *)c->vc_origin,
length);
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
}
/* interface routine */
@ -690,7 +691,7 @@ sisusbcon_set_palette(struct vc_data *c, unsigned char *table)
/* sisusb->lock is down */
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return -EINVAL;
}
@ -705,7 +706,7 @@ sisusbcon_set_palette(struct vc_data *c, unsigned char *table)
break;
}
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 0;
}
@ -728,7 +729,7 @@ sisusbcon_blank(struct vc_data *c, int blank, int mode_switch)
sisusb->is_gfx = blank ? 1 : 0;
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 0;
}
@ -777,7 +778,7 @@ sisusbcon_blank(struct vc_data *c, int blank, int mode_switch)
cr63 = 0x40;
break;
default:
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return -EINVAL;
}
@ -788,7 +789,7 @@ sisusbcon_blank(struct vc_data *c, int blank, int mode_switch)
}
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return ret;
}
@ -809,7 +810,7 @@ sisusbcon_scrolldelta(struct vc_data *c, int lines)
/* sisusb->lock is down */
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 0;
}
@ -849,7 +850,7 @@ sisusbcon_scrolldelta(struct vc_data *c, int lines)
sisusbcon_set_start_address(sisusb, c);
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 1;
}
@ -867,7 +868,7 @@ sisusbcon_cursor(struct vc_data *c, int mode)
/* sisusb->lock is down */
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return;
}
@ -879,7 +880,7 @@ sisusbcon_cursor(struct vc_data *c, int mode)
if (mode == CM_ERASE) {
sisusb_setidxregor(sisusb, SISCR, 0x0a, 0x20);
sisusb->sisusb_cursor_size_to = -1;
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return;
}
@ -919,7 +920,7 @@ sisusbcon_cursor(struct vc_data *c, int mode)
sisusb->sisusb_cursor_size_to = to;
}
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
}
static int
@ -961,7 +962,7 @@ sisusbcon_scroll_area(struct vc_data *c, struct sisusb_usb_data *sisusb,
sisusb_copy_memory(sisusb, (char *)SISUSB_VADDR(0, t),
(u32)SISUSB_HADDR(0, t), length, &written);
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 1;
}
@ -994,7 +995,7 @@ sisusbcon_scroll(struct vc_data *c, int t, int b, int dir, int lines)
/* sisusb->lock is down */
if (sisusb_is_inactive(c, sisusb)) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 0;
}
@ -1084,7 +1085,7 @@ sisusbcon_scroll(struct vc_data *c, int t, int b, int dir, int lines)
c->vc_pos = c->vc_pos - oldorigin + c->vc_origin;
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 1;
}
@ -1106,7 +1107,7 @@ sisusbcon_set_origin(struct vc_data *c)
/* sisusb->lock is down */
if (sisusb_is_inactive(c, sisusb) || sisusb->con_blanked) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 0;
}
@ -1116,7 +1117,7 @@ sisusbcon_set_origin(struct vc_data *c)
sisusb->con_rolled_over = 0;
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 1;
}
@ -1133,7 +1134,7 @@ sisusbcon_resize(struct vc_data *c, unsigned int newcols, unsigned int newrows)
fh = sisusb->current_font_height;
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
/* We are quite unflexible as regards resizing. The vt code
* handles sizes where the line length isn't equal the pitch
@ -1167,7 +1168,7 @@ sisusbcon_do_font_op(struct sisusb_usb_data *sisusb, int set, int slot,
if ((slot != 0 && slot != 2) || !fh) {
if (uplock)
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return -EINVAL;
}
@ -1327,7 +1328,7 @@ sisusbcon_do_font_op(struct sisusb_usb_data *sisusb, int set, int slot,
}
if (uplock)
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
if (dorecalc && c) {
int i, rows = c->vc_scan_lines / fh;
@ -1351,7 +1352,7 @@ sisusbcon_do_font_op(struct sisusb_usb_data *sisusb, int set, int slot,
font_op_error:
if (uplock)
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return -EIO;
}
@ -1417,19 +1418,19 @@ sisusbcon_font_get(struct vc_data *c, struct console_font *font)
font->charcount = 256;
if (!font->data) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 0;
}
if (!sisusb->font_backup) {
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return -ENODEV;
}
/* Copy 256 chars only, like vgacon */
memcpy(font->data, sisusb->font_backup, 256 * 32);
up(&sisusb->lock);
mutex_unlock(&sisusb->lock);
return 0;
}
@ -1512,14 +1513,14 @@ sisusb_console_init(struct sisusb_usb_data *sisusb, int first, int last)
{
int i, ret, minor = sisusb->minor;
down(&disconnect_sem);
mutex_lock(&disconnect_mutex);
down(&sisusb->lock);
mutex_lock(&sisusb->lock);
/* Erm.. that should not happen */
if (sisusb->haveconsole || !sisusb->SiS_Pr) {
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
return 1;
}
@ -1529,15 +1530,15 @@ sisusb_console_init(struct sisusb_usb_data *sisusb, int first, int last)
if (first > last ||
first > MAX_NR_CONSOLES ||
last > MAX_NR_CONSOLES) {
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
return 1;
}
/* If gfxcore not initialized or no consoles given, quit graciously */
if (!sisusb->gfxinit || first < 1 || last < 1) {
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
return 0;
}
@ -1547,8 +1548,8 @@ sisusb_console_init(struct sisusb_usb_data *sisusb, int first, int last)
/* Set up text mode (and upload default font) */
if (sisusb_reset_text_mode(sisusb, 1)) {
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
printk(KERN_ERR
"sisusbvga[%d]: Failed to set up text mode\n",
minor);
@ -1571,16 +1572,16 @@ sisusb_console_init(struct sisusb_usb_data *sisusb, int first, int last)
/* Allocate screen buffer */
if (!(sisusb->scrbuf = (unsigned long)vmalloc(sisusb->scrbuf_size))) {
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
printk(KERN_ERR
"sisusbvga[%d]: Failed to allocate screen buffer\n",
minor);
return 1;
}
up(&sisusb->lock);
up(&disconnect_sem);
mutex_unlock(&sisusb->lock);
mutex_unlock(&disconnect_mutex);
/* Now grab the desired console(s) */
ret = take_over_console(&sisusb_con, first - 1, last - 1, 0);