[linux-2.6-block.git] / drivers / pci / syscall.c

/*
 *	pci_syscall.c
 *
 * For architectures where we want to allow direct access
 * to the PCI config stuff - it would probably be preferable
 * on PCs too, but there people just do it by hand with the
 * magic northbridge registers..
 */

#include <linux/errno.h>
#include <linux/pci.h>
#include <linux/smp_lock.h>
#include <linux/syscalls.h>
#include <asm/uaccess.h>
#include "pci.h"

asmlinkage long
sys_pciconfig_read(unsigned long bus, unsigned long dfn,
		   unsigned long off, unsigned long len,
		   void __user *buf)
{
	struct pci_dev *dev;
	u8 byte;
	u16 word;
	u32 dword;
	long err;
	long cfg_ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	err = -ENODEV;
	dev = pci_get_bus_and_slot(bus, dfn);
	if (!dev)
		goto error;

	lock_kernel();
	switch (len) {
	case 1:
		cfg_ret = pci_user_read_config_byte(dev, off, &byte);
		break;
	case 2:
		cfg_ret = pci_user_read_config_word(dev, off, &word);
		break;
	case 4:
		cfg_ret = pci_user_read_config_dword(dev, off, &dword);
		break;
	default:
		err = -EINVAL;
		unlock_kernel();
		goto error;
	};
	unlock_kernel();

	err = -EIO;
	if (cfg_ret != PCIBIOS_SUCCESSFUL)
		goto error;

	switch (len) {
	case 1:
		err = put_user(byte, (unsigned char __user *)buf);
		break;
	case 2:
		err = put_user(word, (unsigned short __user *)buf);
		break;
	case 4:
		err = put_user(dword, (unsigned int __user *)buf);
		break;
	}
	pci_dev_put(dev);
	return err;

error:
	/* ??? XFree86 doesn't even check the return value.  They
	   just look for 0xffffffff in the output, since that's what
	   they get instead of a machine check on x86.  */
	switch (len) {
	case 1:
		put_user(-1, (unsigned char __user *)buf);
		break;
	case 2:
		put_user(-1, (unsigned short __user *)buf);
		break;
	case 4:
		put_user(-1, (unsigned int __user *)buf);
		break;
	}
	pci_dev_put(dev);
	return err;
}

asmlinkage long
sys_pciconfig_write(unsigned long bus, unsigned long dfn,
		    unsigned long off, unsigned long len,
		    void __user *buf)
{
	struct pci_dev *dev;
	u8 byte;
	u16 word;
	u32 dword;
	int err = 0;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	dev = pci_get_bus_and_slot(bus, dfn);
	if (!dev)
		return -ENODEV;

	lock_kernel();
	switch(len) {
	case 1:
		err = get_user(byte, (u8 __user *)buf);
		if (err)
			break;
		err = pci_user_write_config_byte(dev, off, byte);
		if (err != PCIBIOS_SUCCESSFUL)
			err = -EIO;
		break;

	case 2:
		err = get_user(word, (u16 __user *)buf);
		if (err)
			break;
		err = pci_user_write_config_word(dev, off, word);
		if (err != PCIBIOS_SUCCESSFUL)
			err = -EIO;
		break;

	case 4:
		err = get_user(dword, (u32 __user *)buf);
		if (err)
			break;
		err = pci_user_write_config_dword(dev, off, dword);
		if (err != PCIBIOS_SUCCESSFUL)
			err = -EIO;
		break;

	default:
		err = -EINVAL;
		break;
	}
	unlock_kernel();
	pci_dev_put(dev);
	return err;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* pci_syscall.c
	3	*
	4	* For architectures where we want to allow direct access
	5	* to the PCI config stuff - it would probably be preferable
	6	* on PCs too, but there people just do it by hand with the
	7	* magic northbridge registers..
	8	*/
	9
1da177e4 LT	10	#include <linux/errno.h>
	11	#include <linux/pci.h>
	12	#include <linux/smp_lock.h>
	13	#include <linux/syscalls.h>
	14	#include <asm/uaccess.h>
e04b0ea2	15	#include "pci.h"
1da177e4 LT	16
	17	asmlinkage long
	18	sys_pciconfig_read(unsigned long bus, unsigned long dfn,
	19	unsigned long off, unsigned long len,
	20	void __user *buf)
	21	{
	22	struct pci_dev *dev;
	23	u8 byte;
	24	u16 word;
	25	u32 dword;
e4585da2 AC	26	long err;
e4585da2 AC	27	long cfg_ret;
1da177e4	28
1da177e4	29	if (!capable(CAP_SYS_ADMIN))
e4585da2	30	return -EPERM;
1da177e4 LT	31
1da177e4 LT	32	err = -ENODEV;
e4585da2	33	dev = pci_get_bus_and_slot(bus, dfn);
1da177e4 LT	34	if (!dev)
	35	goto error;
	36
	37	lock_kernel();
	38	switch (len) {
	39	case 1:
e04b0ea2	40	cfg_ret = pci_user_read_config_byte(dev, off, &byte);
1da177e4 LT	41	break;
1da177e4 LT	42	case 2:
e04b0ea2	43	cfg_ret = pci_user_read_config_word(dev, off, &word);
1da177e4 LT	44	break;
1da177e4 LT	45	case 4:
e04b0ea2	46	cfg_ret = pci_user_read_config_dword(dev, off, &dword);
1da177e4 LT	47	break;
	48	default:
	49	err = -EINVAL;
	50	unlock_kernel();
	51	goto error;
	52	};
	53	unlock_kernel();
	54
	55	err = -EIO;
	56	if (cfg_ret != PCIBIOS_SUCCESSFUL)
	57	goto error;
	58
	59	switch (len) {
	60	case 1:
	61	err = put_user(byte, (unsigned char __user *)buf);
	62	break;
	63	case 2:
	64	err = put_user(word, (unsigned short __user *)buf);
	65	break;
	66	case 4:
	67	err = put_user(dword, (unsigned int __user *)buf);
	68	break;
e4585da2 AC	69	}
e4585da2 AC	70	pci_dev_put(dev);
1da177e4 LT	71	return err;
	72
	73	error:
	74	/* ??? XFree86 doesn't even check the return value. They
	75	just look for 0xffffffff in the output, since that's what
	76	they get instead of a machine check on x86. */
	77	switch (len) {
	78	case 1:
	79	put_user(-1, (unsigned char __user *)buf);
	80	break;
	81	case 2:
	82	put_user(-1, (unsigned short __user *)buf);
	83	break;
	84	case 4:
	85	put_user(-1, (unsigned int __user *)buf);
	86	break;
e4585da2 AC	87	}
e4585da2 AC	88	pci_dev_put(dev);
1da177e4 LT	89	return err;
	90	}
	91
	92	asmlinkage long
	93	sys_pciconfig_write(unsigned long bus, unsigned long dfn,
	94	unsigned long off, unsigned long len,
	95	void __user *buf)
	96	{
	97	struct pci_dev *dev;
	98	u8 byte;
	99	u16 word;
	100	u32 dword;
	101	int err = 0;
	102
	103	if (!capable(CAP_SYS_ADMIN))
	104	return -EPERM;
	105
e4585da2	106	dev = pci_get_bus_and_slot(bus, dfn);
1da177e4 LT	107	if (!dev)
	108	return -ENODEV;
	109
	110	lock_kernel();
	111	switch(len) {
	112	case 1:
	113	err = get_user(byte, (u8 __user *)buf);
	114	if (err)
	115	break;
e04b0ea2	116	err = pci_user_write_config_byte(dev, off, byte);
1da177e4 LT	117	if (err != PCIBIOS_SUCCESSFUL)
	118	err = -EIO;
	119	break;
	120
	121	case 2:
	122	err = get_user(word, (u16 __user *)buf);
	123	if (err)
	124	break;
e04b0ea2	125	err = pci_user_write_config_word(dev, off, word);
1da177e4 LT	126	if (err != PCIBIOS_SUCCESSFUL)
	127	err = -EIO;
	128	break;
	129
	130	case 4:
	131	err = get_user(dword, (u32 __user *)buf);
	132	if (err)
	133	break;
e04b0ea2	134	err = pci_user_write_config_dword(dev, off, dword);
1da177e4 LT	135	if (err != PCIBIOS_SUCCESSFUL)
	136	err = -EIO;
	137	break;
	138
	139	default:
	140	err = -EINVAL;
	141	break;
e4585da2	142	}
1da177e4	143	unlock_kernel();
e4585da2	144	pci_dev_put(dev);
1da177e4 LT	145	return err;
1da177e4 LT	146	}