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[PATCH] Char: sx, lock boards struct

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Fix race condition which may occurs when multiple cards are probed at the same
time.  Add mutex to critical sections to avoid this situation.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Jiri Slaby 2006-12-08 02:39:03 -08:00 committed by Linus Torvalds
parent 927a6f9dd0
commit 42f6384fe4
1 changed files with 23 additions and 14 deletions
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37
drivers/char/sx.c
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@ -298,6 +298,7 @@ static int sx_init_drivers(void);
static struct tty_driver *sx_driver;
static DEFINE_MUTEX(sx_boards_lock);
static struct sx_board boards[SX_NBOARDS];
static struct sx_port *sx_ports;
static int sx_initialized;
@ -1980,7 +1981,6 @@ static int sx_init_board (struct sx_board *board)
}
if (chans) {
/* board->flags |= SX_BOARD_PRESENT; */
if(board->irq > 0) {
/* fixed irq, probably PCI */
if(sx_irqmask & (1 << board->irq)) { /* may we use this irq? */
@ -2115,8 +2115,6 @@ static int __devinit probe_sx (struct sx_board *board)
return 0;
sx_dprintk (SX_DEBUG_INIT, "reset the board...\n");
board->flags |= SX_BOARD_PRESENT;
func_exit();
return 1;
}
@ -2211,8 +2209,6 @@ static int __devinit probe_si (struct sx_board *board)
return 0;
sx_dprintk (SX_DEBUG_INIT, "reset the board...\n");
board->flags |= SX_BOARD_PRESENT;
func_exit();
return 1;
}
@ -2396,10 +2392,15 @@ static int __devinit sx_eisa_probe(struct device *dev)
unsigned int i;
int retval = -EIO;
mutex_lock(&sx_boards_lock);
i = sx_find_free_board();
if (i == SX_NBOARDS)
if (i == SX_NBOARDS) {
mutex_unlock(&sx_boards_lock);
goto err;
}
board = &boards[i];
board->flags |= SX_BOARD_PRESENT;
mutex_unlock(&sx_boards_lock);
dev_info(dev, "XIO : Signature found in EISA slot %lu, "
"Product %d Rev %d (REPORT THIS TO LKLM)\n",
@ -2407,7 +2408,6 @@ static int __devinit sx_eisa_probe(struct device *dev)
inb(eisa_slot + EISA_VENDOR_ID_OFFSET + 2),
inb(eisa_slot + EISA_VENDOR_ID_OFFSET + 3));
board = &boards[i];
board->eisa_base = eisa_slot;
board->flags &= ~SX_BOARD_TYPE;
board->flags |= SI_EISA_BOARD;
@ -2430,6 +2430,7 @@ static int __devinit sx_eisa_probe(struct device *dev)
return 0;
err_unmap:
iounmap(board->base);
board->flags &= ~SX_BOARD_PRESENT;
err:
return retval;
}
@ -2498,16 +2499,19 @@ static int __devinit sx_pci_probe(struct pci_dev *pdev,
unsigned int i;
int retval = -EIO;
mutex_lock(&sx_boards_lock);
i = sx_find_free_board();
if (i == SX_NBOARDS)
if (i == SX_NBOARDS) {
mutex_unlock(&sx_boards_lock);
goto err;
}
board = &boards[i];
board->flags |= SX_BOARD_PRESENT;
mutex_unlock(&sx_boards_lock);
retval = pci_enable_device(pdev);
if (retval)
goto err;
board = &boards[i];
goto err_flag;
board->flags &= ~SX_BOARD_TYPE;
board->flags |= (pdev->subsystem_vendor == 0x200) ? SX_PCI_BOARD :
@ -2522,7 +2526,7 @@ static int __devinit sx_pci_probe(struct pci_dev *pdev,
board->base = ioremap(board->hw_base, WINDOW_LEN (board));
if (!board->base) {
dev_err(&pdev->dev, "ioremap failed\n");
goto err;
goto err_flag;
}
/* Most of the stuff on the CF board is offset by 0x18000 .... */
@ -2546,6 +2550,8 @@ static int __devinit sx_pci_probe(struct pci_dev *pdev,
return 0;
err_unmap:
iounmap(board->base2);
err_flag:
board->flags &= ~SX_BOARD_PRESENT;
err:
return retval;
}
@ -2611,6 +2617,7 @@ static int __init sx_init(void)
board->irq = sx_irqmask?-1:0;
if (probe_sx (board)) {
board->flags |= SX_BOARD_PRESENT;
found++;
} else {
iounmap(board->base);
@ -2627,6 +2634,7 @@ static int __init sx_init(void)
board->irq = sx_irqmask ?-1:0;
if (probe_si (board)) {
board->flags |= SX_BOARD_PRESENT;
found++;
} else {
iounmap (board->base);
@ -2642,6 +2650,7 @@ static int __init sx_init(void)
board->irq = sx_irqmask ?-1:0;
if (probe_si (board)) {
board->flags |= SX_BOARD_PRESENT;
found++;
} else {
iounmap (board->base);