freebsd/sys/dev/pci/pci_user.c

/*
 * Copyright (c) 1997, Stefan Esser <se@freebsd.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice unmodified, this list of conditions, and the following
 *    disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * $FreeBSD$
 *
 */

#include "opt_bus.h"	/* XXX trim includes */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/linker.h>
#include <sys/fcntl.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/types.h>

#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_extern.h>

#include <sys/bus.h>
#include <machine/bus.h>
#include <sys/rman.h>
#include <machine/resource.h>

#include <sys/pciio.h>
#include <pci/pcireg.h>
#include <pci/pcivar.h>

#include "pcib_if.h"
#include "pci_if.h"

/*
 * This is the user interface to PCI configuration space.
 */

static d_open_t 	pci_open;
static d_close_t	pci_close;
static int	pci_conf_match(struct pci_match_conf *matches, int num_matches,
			       struct pci_conf *match_buf);
static d_ioctl_t	pci_ioctl;

#define	PCI_CDEV	78

struct cdevsw pcicdev = {
	/* open */	pci_open,
	/* close */	pci_close,
	/* read */	noread,
	/* write */	nowrite,
	/* ioctl */	pci_ioctl,
	/* poll */	nopoll,
	/* mmap */	nommap,
	/* strategy */	nostrategy,
	/* name */	"pci",
	/* maj */	PCI_CDEV,
	/* dump */	nodump,
	/* psize */	nopsize,
	/* flags */	0,
};
  
static int
pci_open(dev_t dev, int oflags, int devtype, struct thread *td)
{
	int error;

	if (oflags & FWRITE) {
		error = securelevel_gt(td->td_ucred, 0);
		if (error)
			return (error);
	}

	return (0);
}

static int
pci_close(dev_t dev, int flag, int devtype, struct thread *td)
{
	return 0;
}

/*
 * Match a single pci_conf structure against an array of pci_match_conf
 * structures.  The first argument, 'matches', is an array of num_matches
 * pci_match_conf structures.  match_buf is a pointer to the pci_conf
 * structure that will be compared to every entry in the matches array.
 * This function returns 1 on failure, 0 on success.
 */
static int
pci_conf_match(struct pci_match_conf *matches, int num_matches, 
	       struct pci_conf *match_buf)
{
	int i;

	if ((matches == NULL) || (match_buf == NULL) || (num_matches <= 0))
		return(1);

	for (i = 0; i < num_matches; i++) {
		/*
		 * I'm not sure why someone would do this...but...
		 */
		if (matches[i].flags == PCI_GETCONF_NO_MATCH)
			continue;

		/*
		 * Look at each of the match flags.  If it's set, do the
		 * comparison.  If the comparison fails, we don't have a
		 * match, go on to the next item if there is one.
		 */
		if (((matches[i].flags & PCI_GETCONF_MATCH_BUS) != 0)
		 && (match_buf->pc_sel.pc_bus != matches[i].pc_sel.pc_bus))
			continue;

		if (((matches[i].flags & PCI_GETCONF_MATCH_DEV) != 0)
		 && (match_buf->pc_sel.pc_dev != matches[i].pc_sel.pc_dev))
			continue;

		if (((matches[i].flags & PCI_GETCONF_MATCH_FUNC) != 0)
		 && (match_buf->pc_sel.pc_func != matches[i].pc_sel.pc_func))
			continue;

		if (((matches[i].flags & PCI_GETCONF_MATCH_VENDOR) != 0) 
		 && (match_buf->pc_vendor != matches[i].pc_vendor))
			continue;

		if (((matches[i].flags & PCI_GETCONF_MATCH_DEVICE) != 0)
		 && (match_buf->pc_device != matches[i].pc_device))
			continue;

		if (((matches[i].flags & PCI_GETCONF_MATCH_CLASS) != 0)
		 && (match_buf->pc_class != matches[i].pc_class))
			continue;

		if (((matches[i].flags & PCI_GETCONF_MATCH_UNIT) != 0)
		 && (match_buf->pd_unit != matches[i].pd_unit))
			continue;

		if (((matches[i].flags & PCI_GETCONF_MATCH_NAME) != 0)
		 && (strncmp(matches[i].pd_name, match_buf->pd_name,
			     sizeof(match_buf->pd_name)) != 0))
			continue;

		return(0);
	}

	return(1);
}

static int
pci_ioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct thread *td)
{
	device_t pci, pcib;
	struct pci_io *io;
	const char *name;
	int error;

	if (!(flag & FWRITE))
		return EPERM;


	switch(cmd) {
	case PCIOCGETCONF:
		{
		struct pci_devinfo *dinfo;
		struct pci_conf_io *cio;
		struct devlist *devlist_head;
		struct pci_match_conf *pattern_buf;
		int num_patterns;
		size_t iolen;
		int ionum, i;

		cio = (struct pci_conf_io *)data;

		num_patterns = 0;
		dinfo = NULL;

		/*
		 * Hopefully the user won't pass in a null pointer, but it
		 * can't hurt to check.
		 */
		if (cio == NULL) {
			error = EINVAL;
			break;
		}

		/*
		 * If the user specified an offset into the device list,
		 * but the list has changed since they last called this
		 * ioctl, tell them that the list has changed.  They will
		 * have to get the list from the beginning.
		 */
		if ((cio->offset != 0)
		 && (cio->generation != pci_generation)){
			cio->num_matches = 0;	
			cio->status = PCI_GETCONF_LIST_CHANGED;
			error = 0;
			break;
		}

		/*
		 * Check to see whether the user has asked for an offset
		 * past the end of our list.
		 */
		if (cio->offset >= pci_numdevs) {
			cio->num_matches = 0;
			cio->status = PCI_GETCONF_LAST_DEVICE;
			error = 0;
			break;
		}

		/* get the head of the device queue */
		devlist_head = &pci_devq;

		/*
		 * Determine how much room we have for pci_conf structures.
		 * Round the user's buffer size down to the nearest
		 * multiple of sizeof(struct pci_conf) in case the user
		 * didn't specify a multiple of that size.
		 */
		iolen = min(cio->match_buf_len - 
			    (cio->match_buf_len % sizeof(struct pci_conf)),
			    pci_numdevs * sizeof(struct pci_conf));

		/*
		 * Since we know that iolen is a multiple of the size of
		 * the pciconf union, it's okay to do this.
		 */
		ionum = iolen / sizeof(struct pci_conf);

		/*
		 * If this test is true, the user wants the pci_conf
		 * structures returned to match the supplied entries.
		 */
		if ((cio->num_patterns > 0)
		 && (cio->pat_buf_len > 0)) {
			/*
			 * pat_buf_len needs to be:
			 * num_patterns * sizeof(struct pci_match_conf)
			 * While it is certainly possible the user just
			 * allocated a large buffer, but set the number of
			 * matches correctly, it is far more likely that
			 * their kernel doesn't match the userland utility
			 * they're using.  It's also possible that the user
			 * forgot to initialize some variables.  Yes, this
			 * may be overly picky, but I hazard to guess that
			 * it's far more likely to just catch folks that
			 * updated their kernel but not their userland.
			 */
			if ((cio->num_patterns *
			    sizeof(struct pci_match_conf)) != cio->pat_buf_len){
				/* The user made a mistake, return an error*/
				cio->status = PCI_GETCONF_ERROR;
				printf("pci_ioctl: pat_buf_len %d != "
				       "num_patterns (%d) * sizeof(struct "
				       "pci_match_conf) (%d)\npci_ioctl: "
				       "pat_buf_len should be = %d\n",
				       cio->pat_buf_len, cio->num_patterns,
				       (int)sizeof(struct pci_match_conf),
				       (int)sizeof(struct pci_match_conf) * 
				       cio->num_patterns);
				printf("pci_ioctl: do your headers match your "
				       "kernel?\n");
				cio->num_matches = 0;
				error = EINVAL;
				break;
			}

			/*
			 * Check the user's buffer to make sure it's readable.
			 */
			if (!useracc((caddr_t)cio->patterns,
				    cio->pat_buf_len, VM_PROT_READ)) {
				printf("pci_ioctl: pattern buffer %p, "
				       "length %u isn't user accessible for"
				       " READ\n", cio->patterns,
				       cio->pat_buf_len);
				error = EACCES;
				break;
			}
			/*
			 * Allocate a buffer to hold the patterns.
			 */
			pattern_buf = malloc(cio->pat_buf_len, M_TEMP,
					     0);
			error = copyin(cio->patterns, pattern_buf,
				       cio->pat_buf_len);
			if (error != 0)
				break;
			num_patterns = cio->num_patterns;

		} else if ((cio->num_patterns > 0)
			|| (cio->pat_buf_len > 0)) {
			/*
			 * The user made a mistake, spit out an error.
			 */
			cio->status = PCI_GETCONF_ERROR;
			cio->num_matches = 0;
			printf("pci_ioctl: invalid GETCONF arguments\n");
			error = EINVAL;
			break;
		} else
			pattern_buf = NULL;

		/*
		 * Make sure we can write to the match buffer.
		 */
		if (!useracc((caddr_t)cio->matches,
			     cio->match_buf_len, VM_PROT_WRITE)) {
			printf("pci_ioctl: match buffer %p, length %u "
			       "isn't user accessible for WRITE\n",
			       cio->matches, cio->match_buf_len);
			error = EACCES;
			break;
		}

		/*
		 * Go through the list of devices and copy out the devices
		 * that match the user's criteria.
		 */
		for (cio->num_matches = 0, error = 0, i = 0,
		     dinfo = STAILQ_FIRST(devlist_head);
		     (dinfo != NULL) && (cio->num_matches < ionum)
		     && (error == 0) && (i < pci_numdevs);
		     dinfo = STAILQ_NEXT(dinfo, pci_links), i++) {

			if (i < cio->offset)
				continue;

			/* Populate pd_name and pd_unit */
			name = NULL;
			if (dinfo->cfg.dev && dinfo->conf.pd_name[0] == '\0')
				name = device_get_name(dinfo->cfg.dev);
			if (name) {
				strncpy(dinfo->conf.pd_name, name,
					sizeof(dinfo->conf.pd_name));
				dinfo->conf.pd_name[PCI_MAXNAMELEN] = 0;
				dinfo->conf.pd_unit =
					device_get_unit(dinfo->cfg.dev);
			}

			if ((pattern_buf == NULL) ||
			    (pci_conf_match(pattern_buf, num_patterns,
					    &dinfo->conf) == 0)) {

				/*
				 * If we've filled up the user's buffer,
				 * break out at this point.  Since we've
				 * got a match here, we'll pick right back
				 * up at the matching entry.  We can also
				 * tell the user that there are more matches
				 * left.
				 */
				if (cio->num_matches >= ionum)
					break;

				error = copyout(&dinfo->conf,
					        &cio->matches[cio->num_matches],
						sizeof(struct pci_conf));
				cio->num_matches++;
			}
		}

		/*
		 * Set the pointer into the list, so if the user is getting
		 * n records at a time, where n < pci_numdevs,
		 */
		cio->offset = i;

		/*
		 * Set the generation, the user will need this if they make
		 * another ioctl call with offset != 0.
		 */
		cio->generation = pci_generation;
		
		/*
		 * If this is the last device, inform the user so he won't
		 * bother asking for more devices.  If dinfo isn't NULL, we
		 * know that there are more matches in the list because of
		 * the way the traversal is done.
		 */
		if (dinfo == NULL)
			cio->status = PCI_GETCONF_LAST_DEVICE;
		else
			cio->status = PCI_GETCONF_MORE_DEVS;

		if (pattern_buf != NULL)
			free(pattern_buf, M_TEMP);

		break;
		}
	case PCIOCREAD:
		io = (struct pci_io *)data;
		switch(io->pi_width) {
		case 4:
		case 2:
		case 1:
			/*
			 * Assume that the user-level bus number is
			 * actually the pciN instance number. We map
			 * from that to the real pcib+bus combination.
			 */
			pci = devclass_get_device(devclass_find("pci"),
						  io->pi_sel.pc_bus);
			if (pci) {
				int b = pcib_get_bus(pci);
				pcib = device_get_parent(pci);
				io->pi_data =
					PCIB_READ_CONFIG(pcib,
							 b,
							 io->pi_sel.pc_dev,
							 io->pi_sel.pc_func,
							 io->pi_reg,
							 io->pi_width);
				error = 0;
			} else {
				error = ENODEV;
			}
			break;
		default:
			error = ENODEV;
			break;
		}
		break;

	case PCIOCWRITE:
		io = (struct pci_io *)data;
		switch(io->pi_width) {
		case 4:
		case 2:
		case 1:
			/*
			 * Assume that the user-level bus number is
			 * actually the pciN instance number. We map
			 * from that to the real pcib+bus combination.
			 */
			pci = devclass_get_device(devclass_find("pci"),
						  io->pi_sel.pc_bus);
			if (pci) {
				int b = pcib_get_bus(pci);
				pcib = device_get_parent(pci);
				PCIB_WRITE_CONFIG(pcib,
						  b,
						  io->pi_sel.pc_dev,
						  io->pi_sel.pc_func,
						  io->pi_reg,
						  io->pi_data,
						  io->pi_width);
				error = 0;
			} else {
				error = ENODEV;
			}
			break;
		default:
			error = ENODEV;
			break;
		}
		break;

	default:
		error = ENOTTY;
		break;
	}

	return (error);
}