cregit-Linux how code gets into the kernel

Release 4.14 arch/x86/kernel/cpu/mtrr/main.c

Directory: arch/x86/kernel/cpu/mtrr
/*  Generic MTRR (Memory Type Range Register) driver.

    Copyright (C) 1997-2000  Richard Gooch
    Copyright (c) 2002       Patrick Mochel

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

    Richard Gooch may be reached by email at  rgooch@atnf.csiro.au
    The postal address is:
      Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia.

    Source: "Pentium Pro Family Developer's Manual, Volume 3:
    Operating System Writer's Guide" (Intel document number 242692),
    section 11.11.7

    This was cleaned and made readable by Patrick Mochel <mochel@osdl.org>
    on 6-7 March 2002.
    Source: Intel Architecture Software Developers Manual, Volume 3:
    System Programming Guide; Section 9.11. (1997 edition - PPro).
*/


#define DEBUG

#include <linux/types.h> /* FIXME: kvm_para.h needs this */

#include <linux/stop_machine.h>
#include <linux/kvm_para.h>
#include <linux/uaccess.h>
#include <linux/export.h>
#include <linux/mutex.h>
#include <linux/init.h>
#include <linux/sort.h>
#include <linux/cpu.h>
#include <linux/pci.h>
#include <linux/smp.h>
#include <linux/syscore_ops.h>

#include <asm/cpufeature.h>
#include <asm/e820/api.h>
#include <asm/mtrr.h>
#include <asm/msr.h>
#include <asm/pat.h>

#include "mtrr.h"

/* arch_phys_wc_add returns an MTRR register index plus this offset. */

#define MTRR_TO_PHYS_WC_OFFSET 1000


u32 num_var_ranges;

static bool __mtrr_enabled;




static bool mtrr_enabled(void)
{
	return __mtrr_enabled;
}


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unsigned int mtrr_usage_table[MTRR_MAX_VAR_RANGES];
static DEFINE_MUTEX(mtrr_mutex);



u64 size_or_mask, size_and_mask;

static bool mtrr_aps_delayed_init;


static const struct mtrr_ops *mtrr_ops[X86_VENDOR_NUM] __ro_after_init;


const struct mtrr_ops *mtrr_if;

static void set_mtrr(unsigned int reg, unsigned long base,
		     unsigned long size, mtrr_type type);




void __init set_mtrr_ops(const struct mtrr_ops *ops)
{
	if (ops->vendor && ops->vendor < X86_VENDOR_NUM)
		mtrr_ops[ops->vendor] = ops;
}


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Emese Revfy13.03%133.33%


Kees Cook13.03%133.33%


Total33100.00%3100.00%



/*  Returns non-zero if we have the write-combining memory type  */



static int have_wrcomb(void)
{
	struct pci_dev *dev;

	dev = pci_get_class(PCI_CLASS_BRIDGE_HOST << 8, NULL);
	if (dev != NULL) {
		/*
                 * ServerWorks LE chipsets < rev 6 have problems with
                 * write-combining. Don't allow it and leave room for other
                 * chipsets to be tagged
                 */
		if (dev->vendor == PCI_VENDOR_ID_SERVERWORKS &&
		    dev->device == PCI_DEVICE_ID_SERVERWORKS_LE &&
		    dev->revision <= 5) {
			pr_info("mtrr: Serverworks LE rev < 6 detected. Write-combining disabled.\n");
			pci_dev_put(dev);
			return 0;
		}
		/*
                 * Intel 450NX errata # 23. Non ascending cacheline evictions to
                 * write combining memory may resulting in data corruption
                 */
		if (dev->vendor == PCI_VENDOR_ID_INTEL &&
		    dev->device == PCI_DEVICE_ID_INTEL_82451NX) {
			pr_info("mtrr: Intel 450NX MMC detected. Write-combining disabled.\n");
			pci_dev_put(dev);
			return 0;
		}
		pci_dev_put(dev);
	}
	return mtrr_if->have_wrcomb ? mtrr_if->have_wrcomb() : 0;
}


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Alan Cox2320.00%116.67%


Greg Kroah-Hartman1613.91%116.67%


Jaswinder Singh Rajput86.96%116.67%


Lee Revell65.22%116.67%


Sergei Shtylyov32.61%116.67%


Total115100.00%6100.00%



/*  This function returns the number of variable MTRRs  */



static void __init set_num_var_ranges(void)
{
	unsigned long config = 0, dummy;

	if (use_intel())
		rdmsr(MSR_MTRRcap, config, dummy);
	else if (is_cpu(AMD))
		config = 2;
	else if (is_cpu(CYRIX) || is_cpu(CENTAUR))
		config = 8;

	num_var_ranges = config & 0xff;
}


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Dave Jones6496.97%133.33%


Jaswinder Singh Rajput11.52%133.33%


Andries E. Brouwer11.52%133.33%


Total66100.00%3100.00%






static void __init init_table(void)
{
	int i, max;

	max = num_var_ranges;
	for (i = 0; i < max; i++)
		mtrr_usage_table[i] = 1;
}


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Dave Jones3694.74%133.33%


Jesse Barnes12.63%133.33%


Andrew Morton12.63%133.33%


Total38100.00%3100.00%




struct set_mtrr_data {
	
unsigned long	smp_base;
	
unsigned long	smp_size;
	
unsigned int	smp_reg;
	
mtrr_type	smp_type;
};

/**
 * mtrr_rendezvous_handler - Work done in the synchronization handler. Executed
 * by all the CPUs.
 * @info: pointer to mtrr configuration data
 *
 * Returns nothing.
 */



static int mtrr_rendezvous_handler(void *info)
{
	struct set_mtrr_data *data = info;

	/*
         * We use this same function to initialize the mtrrs during boot,
         * resume, runtime cpu online and on an explicit request to set a
         * specific MTRR.
         *
         * During boot or suspend, the state of the boot cpu's mtrrs has been
         * saved, and we want to replicate that across all the cpus that come
         * online (either at the end of boot or resume or during a runtime cpu
         * online). If we're doing that, @reg is set to something special and on
         * all the cpu's we do mtrr_if->set_all() (On the logical cpu that
         * started the boot/resume sequence, this might be a duplicate
         * set_all()).
         */
	if (data->smp_reg != ~0U) {
		mtrr_if->set(data->smp_reg, data->smp_base,
			     data->smp_size, data->smp_type);
	} else if (mtrr_aps_delayed_init || !cpu_online(smp_processor_id())) {
		mtrr_if->set_all();
	}
	return 0;
}


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Dave Jones3548.61%112.50%


Suresh B. Siddha1825.00%337.50%


Patrick Mochel1318.06%112.50%


Jaswinder Singh Rajput45.56%112.50%


Ingo Molnar11.39%112.50%


Andi Kleen11.39%112.50%


Total72100.00%8100.00%






static inline int types_compatible(mtrr_type type1, mtrr_type type2)
{
	return type1 == MTRR_TYPE_UNCACHABLE ||
	       type2 == MTRR_TYPE_UNCACHABLE ||
	       (type1 == MTRR_TYPE_WRTHROUGH && type2 == MTRR_TYPE_WRBACK) ||
	       (type1 == MTRR_TYPE_WRBACK && type2 == MTRR_TYPE_WRTHROUGH);
}


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Total42100.00%1100.00%



/**
 * set_mtrr - update mtrrs on all processors
 * @reg:        mtrr in question
 * @base:       mtrr base
 * @size:       mtrr size
 * @type:       mtrr type
 *
 * This is kinda tricky, but fortunately, Intel spelled it out for us cleanly:
 *
 * 1. Queue work to do the following on all processors:
 * 2. Disable Interrupts
 * 3. Wait for all procs to do so
 * 4. Enter no-fill cache mode
 * 5. Flush caches
 * 6. Clear PGE bit
 * 7. Flush all TLBs
 * 8. Disable all range registers
 * 9. Update the MTRRs
 * 10. Enable all range registers
 * 11. Flush all TLBs and caches again
 * 12. Enter normal cache mode and reenable caching
 * 13. Set PGE
 * 14. Wait for buddies to catch up
 * 15. Enable interrupts.
 *
 * What does that mean for us? Well, stop_machine() will ensure that
 * the rendezvous handler is started on each CPU. And in lockstep they
 * do the state transition of disabling interrupts, updating MTRR's
 * (the CPU vendors may each do it differently, so we call mtrr_if->set()
 * callback and let them take care of it.) and enabling interrupts.
 *
 * Note that the mechanism is the same for UP systems, too; all the SMP stuff
 * becomes nops.
 */


static void

set_mtrr(unsigned int reg, unsigned long base, unsigned long size, mtrr_type type)
{
	struct set_mtrr_data data = { .smp_reg = reg,
				      .smp_base = base,
				      .smp_size = size,
				      .smp_type = type
				    };

	stop_machine(mtrr_rendezvous_handler, &data, cpu_online_mask);
}


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Dave Jones4477.19%133.33%


Suresh B. Siddha1322.81%266.67%


Total57100.00%3100.00%






static void set_mtrr_cpuslocked(unsigned int reg, unsigned long base,
				unsigned long size, mtrr_type type)
{
	struct set_mtrr_data data = { .smp_reg = reg,
				      .smp_base = base,
				      .smp_size = size,
				      .smp_type = type
				    };

	stop_machine_cpuslocked(mtrr_rendezvous_handler, &data, cpu_online_mask);
}


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Total57100.00%1100.00%






static void set_mtrr_from_inactive_cpu(unsigned int reg, unsigned long base,
				      unsigned long size, mtrr_type type)
{
	struct set_mtrr_data data = { .smp_reg = reg,
				      .smp_base = base,
				      .smp_size = size,
				      .smp_type = type
				    };

	stop_machine_from_inactive_cpu(mtrr_rendezvous_handler, &data,
				       cpu_callout_mask);
}


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Suresh B. Siddha4782.46%250.00%


Dave Jones814.04%125.00%


Andrew Morton23.51%125.00%


Total57100.00%4100.00%



/**
 * mtrr_add_page - Add a memory type region
 * @base: Physical base address of region in pages (in units of 4 kB!)
 * @size: Physical size of region in pages (4 kB)
 * @type: Type of MTRR desired
 * @increment: If this is true do usage counting on the region
 *
 * Memory type region registers control the caching on newer Intel and
 * non Intel processors. This function allows drivers to request an
 * MTRR is added. The details and hardware specifics of each processor's
 * implementation are hidden from the caller, but nevertheless the
 * caller should expect to need to provide a power of two size on an
 * equivalent power of two boundary.
 *
 * If the region cannot be added either because all regions are in use
 * or the CPU cannot support it a negative value is returned. On success
 * the register number for this entry is returned, but should be treated
 * as a cookie only.
 *
 * On a multiprocessor machine the changes are made to all processors.
 * This is required on x86 by the Intel processors.
 *
 * The available types are
 *
 * %MTRR_TYPE_UNCACHABLE - No caching
 *
 * %MTRR_TYPE_WRBACK - Write data back in bursts whenever
 *
 * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts
 *
 * %MTRR_TYPE_WRTHROUGH - Cache reads but not writes
 *
 * BUGS: Needs a quiet flag for the cases where drivers do not mind
 * failures and do not wish system log messages to be sent.
 */



int mtrr_add_page(unsigned long base, unsigned long size,
		  unsigned int type, bool increment)
{
	unsigned long lbase, lsize;
	int i, replace, error;
	mtrr_type ltype;

	if (!mtrr_enabled())
		return -ENXIO;

	error = mtrr_if->validate_add_page(base, size, type);
	if (error)
		return error;

	if (type >= MTRR_NUM_TYPES) {
		pr_warn("mtrr: type: %u invalid\n", type);
		return -EINVAL;
	}

	/* If the type is WC, check that this processor supports it */
	if ((type == MTRR_TYPE_WRCOMB) && !have_wrcomb()) {
		pr_warn("mtrr: your processor doesn't support write-combining\n");
		return -ENOSYS;
	}

	if (!size) {
		pr_warn("mtrr: zero sized request\n");
		return -EINVAL;
	}

	if ((base | (base + size - 1)) >>
	    (boot_cpu_data.x86_phys_bits - PAGE_SHIFT)) {
		pr_warn("mtrr: base or size exceeds the MTRR width\n");
		return -EINVAL;
	}

	error = -EINVAL;
	replace = -1;

	/* No CPU hotplug when we change MTRR entries */
	get_online_cpus();

	/* Search for existing MTRR  */
	mutex_lock(&mtrr_mutex);
	for (i = 0; i < num_var_ranges; ++i) {
		mtrr_if->get(i, &lbase, &lsize, &ltype);
		if (!lsize || base > lbase + lsize - 1 ||
		    base + size - 1 < lbase)
			continue;
		/*
                 * At this point we know there is some kind of
                 * overlap/enclosure
                 */
		if (base < lbase || base + size - 1 > lbase + lsize - 1) {
			if (base <= lbase &&
			    base + size - 1 >= lbase + lsize - 1) {
				/*  New region encloses an existing region  */
				if (type == ltype) {
					replace = replace == -1 ? i : -2;
					continue;
				} else if (types_compatible(type, ltype))
					continue;
			}
			pr_warn("mtrr: 0x%lx000,0x%lx000 overlaps existing"
				" 0x%lx000,0x%lx000\n", base, size, lbase,
				lsize);
			goto out;
		}
		/* New region is enclosed by an existing region */
		if (ltype != type) {
			if (types_compatible(type, ltype))
				continue;
			pr_warn("mtrr: type mismatch for %lx000,%lx000 old: %s new: %s\n",
				base, size, mtrr_attrib_to_str(ltype),
				mtrr_attrib_to_str(type));
			goto out;
		}
		if (increment)
			++mtrr_usage_table[i];
		error = i;
		goto out;
	}
	/* Search for an empty MTRR */
	i = mtrr_if->get_free_region(base, size, replace);
	if (i >= 0) {
		set_mtrr_cpuslocked(i, base, size, type);
		if (likely(replace < 0)) {
			mtrr_usage_table[i] = 1;
		} else {
			mtrr_usage_table[i] = mtrr_usage_table[replace];
			if (increment)
				mtrr_usage_table[i]++;
			if (unlikely(replace != i)) {
				set_mtrr_cpuslocked(replace, 0, 0, 0);
				mtrr_usage_table[replace] = 0;
			}
		}
	} else {
		pr_info("mtrr: no more MTRRs available\n");
	}
	error = i;
 out:
	mutex_unlock(&mtrr_mutex);
	put_online_cpus();
	return error;
}


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Dave Jones29056.86%17.14%


Jan Beulich14428.24%17.14%


Jaswinder Singh Rajput183.53%17.14%


Yinghai Lu173.33%17.14%


Paul Jimenez91.76%17.14%


Jesse Barnes81.57%17.14%


Chen Yucong61.18%17.14%


David Shaohua Li50.98%17.14%


Ingo Molnar40.78%17.14%


Andrew Morton20.39%17.14%


Thomas Gleixner20.39%17.14%


Gautham R. Shenoy20.39%17.14%


Luis R. Rodriguez20.39%17.14%


Alan Cox10.20%17.14%


Total510100.00%14100.00%






static int mtrr_check(unsigned long base, unsigned long size)
{
	if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1))) {
		pr_warn("mtrr: size and base must be multiples of 4 kiB\n");
		pr_debug("mtrr: size: 0x%lx  base: 0x%lx\n", size, base);
		dump_stack();
		return -1;
	}
	return 0;
}


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Dave Jones5182.26%125.00%


Andrew Morton914.52%125.00%


Chen Yucong11.61%125.00%


Jaswinder Singh Rajput11.61%125.00%


Total62100.00%4100.00%



/**
 * mtrr_add - Add a memory type region
 * @base: Physical base address of region
 * @size: Physical size of region
 * @type: Type of MTRR desired
 * @increment: If this is true do usage counting on the region
 *
 * Memory type region registers control the caching on newer Intel and
 * non Intel processors. This function allows drivers to request an
 * MTRR is added. The details and hardware specifics of each processor's
 * implementation are hidden from the caller, but nevertheless the
 * caller should expect to need to provide a power of two size on an
 * equivalent power of two boundary.
 *
 * If the region cannot be added either because all regions are in use
 * or the CPU cannot support it a negative value is returned. On success
 * the register number for this entry is returned, but should be treated
 * as a cookie only.
 *
 * On a multiprocessor machine the changes are made to all processors.
 * This is required on x86 by the Intel processors.
 *
 * The available types are
 *
 * %MTRR_TYPE_UNCACHABLE - No caching
 *
 * %MTRR_TYPE_WRBACK - Write data back in bursts whenever
 *
 * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts
 *
 * %MTRR_TYPE_WRTHROUGH - Cache reads but not writes
 *
 * BUGS: Needs a quiet flag for the cases where drivers do not mind
 * failures and do not wish system log messages to be sent.
 */



int mtrr_add(unsigned long base, unsigned long size, unsigned int type,
	     bool increment)
{
	if (!mtrr_enabled())
		return -ENODEV;
	if (mtrr_check(base, size))
		return -EINVAL;
	return mtrr_add_page(base >> PAGE_SHIFT, size >> PAGE_SHIFT, type,
			     increment);
}


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Andrew Morton3152.54%120.00%


Dave Jones1627.12%120.00%


Luis R. Rodriguez1016.95%120.00%


Jaswinder Singh Rajput11.69%120.00%


Paul Jimenez11.69%120.00%


Total59100.00%5100.00%



/**
 * mtrr_del_page - delete a memory type region
 * @reg: Register returned by mtrr_add
 * @base: Physical base address
 * @size: Size of region
 *
 * If register is supplied then base and size are ignored. This is
 * how drivers should call it.
 *
 * Releases an MTRR region. If the usage count drops to zero the
 * register is freed and the region returns to default state.
 * On success the register is returned, on failure a negative error
 * code.
 */



int mtrr_del_page(int reg, unsigned long base, unsigned long size)
{
	int i, max;
	mtrr_type ltype;
	unsigned long lbase, lsize;
	int error = -EINVAL;

	if (!mtrr_enabled())
		return -ENODEV;

	max = num_var_ranges;
	/* No CPU hotplug when we change MTRR entries */
	get_online_cpus();
	mutex_lock(&mtrr_mutex);
	if (reg < 0) {
		/*  Search for existing MTRR  */
		for (i = 0; i < max; ++i) {
			mtrr_if->get(i, &lbase, &lsize, &ltype);
			if (lbase == base && lsize == size) {
				reg = i;
				break;
			}
		}
		if (reg < 0) {
			pr_debug("mtrr: no MTRR for %lx000,%lx000 found\n",
				 base, size);
			goto out;
		}
	}
	if (reg >= max) {
		pr_warn("mtrr: register: %d too big\n", reg);
		goto out;
	}
	mtrr_if->get(reg, &lbase, &lsize, &ltype);
	if (lsize < 1) {
		pr_warn("mtrr: MTRR %d not used\n", reg);
		goto out;
	}
	if (mtrr_usage_table[reg] < 1) {
		pr_warn("mtrr: reg: %d has count=0\n", reg);
		goto out;
	}
	if (--mtrr_usage_table[reg] < 1)
		set_mtrr_cpuslocked(reg, 0, 0, 0);
	error = reg;
 out:
	mutex_unlock(&mtrr_mutex);
	put_online_cpus();
	return error;
}


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Dave Jones22791.16%110.00%


David Shaohua Li52.01%110.00%


Ingo Molnar41.61%110.00%


Chen Yucong31.20%110.00%


Luis R. Rodriguez31.20%110.00%


Jesse Barnes20.80%110.00%


Gautham R. Shenoy20.80%110.00%


Jaswinder Singh Rajput10.40%110.00%


Jan Beulich10.40%110.00%


Thomas Gleixner10.40%110.00%


Total249100.00%10100.00%



/**
 * mtrr_del - delete a memory type region
 * @reg: Register returned by mtrr_add
 * @base: Physical base address
 * @size: Size of region
 *
 * If register is supplied then base and size are ignored. This is
 * how drivers should call it.
 *
 * Releases an MTRR region. If the usage count drops to zero the
 * register is freed and the region returns to default state.
 * On success the register is returned, on failure a negative error
 * code.
 */



int mtrr_del(int reg, unsigned long base, unsigned long size)
{
	if (!mtrr_enabled())
		return -ENODEV;
	if (mtrr_check(base, size))
		return -EINVAL;
	return mtrr_del_page(reg, base >> PAGE_SHIFT, size >> PAGE_SHIFT);
}


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Luis R. Rodriguez1018.87%125.00%


Andrew Morton35.66%125.00%


Jaswinder Singh Rajput11.89%125.00%


Total53100.00%4100.00%



/**
 * arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable
 * @base: Physical base address
 * @size: Size of region
 *
 * If PAT is available, this does nothing.  If PAT is unavailable, it
 * attempts to add a WC MTRR covering size bytes starting at base and
 * logs an error if this fails.
 *
 * The called should provide a power of two size on an equivalent
 * power of two boundary.
 *
 * Drivers must store the return value to pass to mtrr_del_wc_if_needed,
 * but drivers should not try to interpret that return value.
 */



int arch_phys_wc_add(unsigned long base, unsigned long size)
{
	int ret;

	if (pat_enabled() || !mtrr_enabled())
		return 0;  /* Success!  (We don't need to do anything.) */

	ret = mtrr_add(base, size, MTRR_TYPE_WRCOMB, true);
	if (ret < 0) {
		pr_warn("Failed to add WC MTRR for [%p-%p]; performance may suffer.",
			(void *)base, (void *)(base + size - 1));
		return ret;
	}
	return ret + MTRR_TO_PHYS_WC_OFFSET;
}

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Total81100.00%3100.00%




EXPORT_SYMBOL(arch_phys_wc_add);

/*
 * arch_phys_wc_del - undoes arch_phys_wc_add
 * @handle: Return value from arch_phys_wc_add
 *
 * This cleans up after mtrr_add_wc_if_needed.
 *
 * The API guarantees that mtrr_del_wc_if_needed(error code) and
 * mtrr_del_wc_if_needed(0) do nothing.
 */



void arch_phys_wc_del(int handle)
{
	if (handle >= 1) {
		WARN_ON(handle < MTRR_TO_PHYS_WC_OFFSET);
		mtrr_del(handle - MTRR_TO_PHYS_WC_OFFSET, 0, 0);
	}
}

Contributors
PersonTokensPropCommitsCommitProp
Andrew Lutomirski34100.00%1100.00%


Total34100.00%1100.00%




EXPORT_SYMBOL(arch_phys_wc_del);

/*
 * arch_phys_wc_index - translates arch_phys_wc_add's return value
 * @handle: Return value from arch_phys_wc_add
 *
 * This will turn the return value from arch_phys_wc_add into an mtrr
 * index suitable for debugging.
 *
 * Note: There is no legitimate use for this function, except possibly
 * in printk line.  Alas there is an illegitimate use in some ancient
 * drm ioctls.
 */



int arch_phys_wc_index(int handle)
{
	if (handle < MTRR_TO_PHYS_WC_OFFSET)
		return -1;
	else
		return handle - MTRR_TO_PHYS_WC_OFFSET;
}

Contributors
PersonTokensPropCommitsCommitProp
Andrew Lutomirski2395.83%150.00%


Luis R. Rodriguez14.17%150.00%


Total24100.00%2100.00%




EXPORT_SYMBOL_GPL(arch_phys_wc_index);

/*
 * HACK ALERT!
 * These should be called implicitly, but we can't yet until all the initcall
 * stuff is done...
 */



static void __init init_ifs(void)
{
#ifndef CONFIG_X86_64
	amd_init_mtrr();
	cyrix_init_mtrr();
	centaur_init_mtrr();
#endif
}


Contributors
PersonTokensPropCommitsCommitProp
Dave Jones1878.26%150.00%


Jan Beulich521.74%150.00%


Total23100.00%2100.00%



/* The suspend/resume methods are only for CPU without MTRR. CPU using generic
 * MTRR driver doesn't require this
 */

struct mtrr_value {
	
mtrr_type	ltype;
	
unsigned long	lbase;
	
unsigned long	lsize;
};


static struct mtrr_value mtrr_value[MTRR_MAX_VAR_RANGES];




static int mtrr_save(void)
{
	int i;

	for (i = 0; i < num_var_ranges; i++) {
		mtrr_if->get(i, &mtrr_value[i].lbase,
				&mtrr_value[i].lsize,
				&mtrr_value[i].ltype);
	}
	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
Patrick Mochel5693.33%133.33%


Yinghai Lu35.00%133.33%


Rafael J. Wysocki11.67%133.33%


Total60100.00%3100.00%






static void mtrr_restore(void)
{
	int i;

	for (i = 0; i < num_var_ranges; i++) {
		if (mtrr_value[i].lsize) {
			set_mtrr(i, mtrr_value[i].lbase,
				    mtrr_value[i].lsize,
				    mtrr_value[i].ltype);
		}
	}
}




Contributors
PersonTokensPropCommitsCommitProp
Patrick Mochel5587.30%125.00%


Yinghai Lu46.35%125.00%


Rafael J. Wysocki23.17%125.00%


Jaswinder Singh Rajput23.17%125.00%


Total63100.00%4100.00%




static struct syscore_ops mtrr_syscore_ops = {
	.suspend	= mtrr_save,
	.resume		= mtrr_restore,
};


int __initdata changed_by_mtrr_cleanup;


#define SIZE_OR_MASK_BITS(n)  (~((1ULL << ((n) - PAGE_SHIFT)) - 1))
/**
 * mtrr_bp_init - initialize mtrrs on the boot CPU
 *
 * This needs to be called early; before any of the other CPUs are
 * initialized (i.e. before smp_init()).
 *
 */



void __init mtrr_bp_init(void)
{
	u32 phys_addr;

	init_ifs();

	phys_addr = 32;

	if (boot_cpu_has(X86_FEATURE_MTRR)) {
		mtrr_if = &generic_mtrr_ops;
		size_or_mask = SIZE_OR_MASK_BITS(36);
		size_and_mask = 0x00f00000;
		phys_addr = 36;

		/*
                 * This is an AMD specific MSR, but we assume(hope?) that
                 * Intel will implement it too when they extend the address
                 * bus of the Xeon.
                 */
		if (cpuid_eax(0x80000000) >= 0x80000008) {
			phys_addr = cpuid_eax(0x80000008) & 0xff;
			/* CPUID workaround for Intel 0F33/0F34 CPU */
			if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
			    boot_cpu_data.x86 == 0xF &&
			    boot_cpu_data.x86_model == 0x3 &&
			    (boot_cpu_data.x86_mask == 0x3 ||
			     boot_cpu_data.x86_mask == 0x4))
				phys_addr = 36;

			size_or_mask = SIZE_OR_MASK_BITS(phys_addr);
			size_and_mask = ~size_or_mask & 0xfffff00000ULL;
		} else if (boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR &&
			   boot_cpu_data.x86 == 6) {
			/*
                         * VIA C* family have Intel style MTRRs,
                         * but don't support PAE
                         */
			size_or_mask = SIZE_OR_MASK_BITS(32);
			size_and_mask = 0;
			phys_addr = 32;
		}
	} else {
		switch (boot_cpu_data.x86_vendor) {
		case X86_VENDOR_AMD:
			if (cpu_feature_enabled(X86_FEATURE_K6_MTRR)) {
				/* Pre-Athlon (K6) AMD CPU MTRRs */
				mtrr_if = mtrr_ops[X86_VENDOR_AMD];
				size_or_mask = SIZE_OR_MASK_BITS(32);
				size_and_mask = 0;
			}
			break;
		case X86_VENDOR_CENTAUR:
			if (cpu_feature_enabled(X86_FEATURE_CENTAUR_MCR)) {
				mtrr_if = mtrr_ops[X86_VENDOR_CENTAUR];
				size_or_mask = SIZE_OR_MASK_BITS(32);
				size_and_mask = 0;
			}
			break;
		case X86_VENDOR_CYRIX:
			if (cpu_feature_enabled(X86_FEATURE_CYRIX_ARR)) {
				mtrr_if = mtrr_ops[X86_VENDOR_CYRIX];
				size_or_mask = SIZE_OR_MASK_BITS(32);
				size_and_mask = 0;
			}
			break;
		default:
			break;
		}
	}

	if (mtrr_if) {
		__mtrr_enabled = true;
		set_num_var_ranges();
		init_table();
		if (use_intel()) {
			/* BIOS may override */
			__mtrr_enabled = get_mtrr_state();

			if (mtrr_enabled())
				mtrr_bp_pat_init();

			if (mtrr_cleanup(phys_addr)) {
				changed_by_mtrr_cleanup = 1;
				mtrr_if->set_all();
			}
		}
	}

	if (!mtrr_enabled()) {
		pr_info("MTRR: Disabled\n");

		/*
                 * PAT initialization relies on MTRR's rendezvous handler.
                 * Skip PAT init until the handler can initialize both
                 * features independently.
                 */
		pat_disable("MTRRs disabled, skipping PAT initialization too.");
	}
}


Contributors
PersonTokensPropCommitsCommitProp
Dave Jones16649.55%15.88%


Yinghai Lu5817.31%317.65%


David Shaohua Li4914.63%211.76%


Luis R. Rodriguez185.37%15.88%


Toshi Kani164.78%211.76%


Dave Hansen123.58%15.88%


Andi Kleen72.09%15.88%


Borislav Petkov41.19%15.88%


Jaswinder Singh Rajput10.30%15.88%


Olaf Hering10.30%15.88%


Patrick Mochel10.30%15.88%


Andreas Herrmann10.30%15.88%


Sam Ravnborg10.30%15.88%


Total335100.00%17100.00%






void mtrr_ap_init(void)
{
	if (!mtrr_enabled())
		return;

	if (!use_intel() || mtrr_aps_delayed_init)
		return;
	/*
         * Ideally we should hold mtrr_mutex here to avoid mtrr entries
         * changed, but this routine will be called in cpu boot time,
         * holding the lock breaks it.
         *
         * This routine is called in two cases:
         *
         *   1. very earily time of software resume, when there absolutely
         *      isn't mtrr entry changes;
         *
         *   2. cpu hotadd time. We let mtrr_add/del_page hold cpuhotplug
         *      lock to prevent mtrr entry changes
         */
	set_mtrr_from_inactive_cpu(~0U, 0, 0, 0);
}


Contributors
PersonTokensPropCommitsCommitProp
David Shaohua Li1747.22%120.00%


Suresh B. Siddha1130.56%240.00%


Luis R. Rodriguez719.44%120.00%


Jaswinder Singh Rajput12.78%120.00%


Total36100.00%5100.00%



/**
 * Save current fixed-range MTRR state of the first cpu in cpu_online_mask.
 */



void mtrr_save_state(void)
{
	int first_cpu;

	if (!mtrr_enabled())
		return;

	first_cpu = cpumask_first(cpu_online_mask);
	smp_call_function_single(first_cpu, mtrr_save_fixed_ranges, NULL, 1);
}


Contributors
PersonTokensPropCommitsCommitProp
Bernhard Kaindl1748.57%133.33%


Fenghua Yu1131.43%133.33%


Luis R. Rodriguez720.00%133.33%


Total35100.00%3100.00%






void set_mtrr_aps_delayed_init(void)
{
	if (!mtrr_enabled())
		return;
	if (!use_intel())
		return;

	mtrr_aps_delayed_init = true;
}


Contributors
PersonTokensPropCommitsCommitProp
Suresh B. Siddha1768.00%133.33%


Luis R. Rodriguez728.00%133.33%


H. Peter Anvin14.00%133.33%


Total25100.00%3100.00%



/*
 * Delayed MTRR initialization for all AP's
 */



void mtrr_aps_init(void)
{
	if (!use_intel() || !mtrr_enabled())
		return;

	/*
         * Check if someone has requested the delay of AP MTRR initialization,
         * by doing set_mtrr_aps_delayed_init(), prior to this point. If not,
         * then we are done.
         */
	if (!mtrr_aps_delayed_init)
		return;

	set_mtrr(~0U, 0, 0, 0);
	mtrr_aps_delayed_init = false;
}


Contributors
PersonTokensPropCommitsCommitProp
Suresh B. Siddha3687.80%250.00%


Luis R. Rodriguez49.76%125.00%


H. Peter Anvin12.44%125.00%


Total41100.00%4100.00%






void mtrr_bp_restore(void)
{
	if (!use_intel() || !mtrr_enabled())
		return;

	mtrr_if->set_all();
}


Contributors
PersonTokensPropCommitsCommitProp
Suresh B. Siddha1982.61%150.00%


Luis R. Rodriguez417.39%150.00%


Total23100.00%2100.00%






static int __init mtrr_init_finialize(void)
{
	if (!mtrr_enabled())
		return 0;

	if (use_intel()) {
		if (!changed_by_mtrr_cleanup)
			mtrr_state_warn();
		return 0;
	}

	/*
         * The CPU has no MTRR and seems to not support SMP. They have
         * specific drivers, we use a tricky method to support
         * suspend/resume for them.
         *
         * TBD: is there any system with such CPU which supports
         * suspend/resume? If no, we should remove the code.
         */
	register_syscore_ops(&mtrr_syscore_ops);

	return 0;
}

Contributors
PersonTokensPropCommitsCommitProp
David Shaohua Li2452.17%112.50%


Yinghai Lu715.22%225.00%


Patrick Mochel48.70%112.50%


Jaswinder Singh Rajput48.70%112.50%


Dave Jones36.52%112.50%


Rafael J. Wysocki24.35%112.50%


Luis R. Rodriguez24.35%112.50%


Total46100.00%8100.00%




subsys_initcall(mtrr_init_finialize);

Overall Contributors
PersonTokensPropCommitsCommitProp
Dave Jones117646.21%11.64%


Jan Beulich1937.58%23.28%


Suresh B. Siddha1696.64%58.20%


Patrick Mochel1696.64%34.92%


Andrew Lutomirski1566.13%11.64%


Yinghai Lu1044.09%58.20%


David Shaohua Li1024.01%23.28%


Luis R. Rodriguez983.85%46.56%


Jaswinder Singh Rajput662.59%23.28%


Thomas Gleixner602.36%11.64%


Andrew Morton481.89%46.56%


Alan Cox240.94%11.64%


Jesse Barnes180.71%11.64%


Bernhard Kaindl170.67%11.64%


Greg Kroah-Hartman160.63%11.64%


Toshi Kani160.63%23.28%


Ingo Molnar140.55%34.92%


Fenghua Yu120.47%11.64%


Dave Hansen120.47%11.64%


Paul Jimenez100.39%11.64%


Rafael J. Wysocki100.39%11.64%


Chen Yucong100.39%11.64%


Andi Kleen80.31%23.28%


Lee Revell60.24%11.64%


Borislav Petkov50.20%23.28%


Gautham R. Shenoy40.16%11.64%


H. Peter Anvin40.16%11.64%


Emese Revfy30.12%11.64%


Sergei Shtylyov30.12%11.64%


Sheng Yang20.08%11.64%


Joerg Roedel20.08%11.64%


Andreas Herrmann20.08%11.64%


Kees Cook20.08%11.64%


Sam Ravnborg10.04%11.64%


Olaf Hering10.04%11.64%


Andries E. Brouwer10.04%11.64%


Paul Gortmaker10.04%11.64%


Total2545100.00%61100.00%


Directory: arch/x86/kernel/cpu/mtrr



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