[apple/xnu.git] / osfmk / x86_64 / copyio.c

/*
 * Copyright (c) 2009-2016 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
#include <mach_assert.h>

#include <sys/errno.h>
#include <i386/param.h>
#include <i386/misc_protos.h>
#include <i386/cpu_data.h>
#include <i386/machine_routines.h>
#include <i386/cpuid.h>
#include <i386/vmx.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_kern.h>
#include <vm/vm_fault.h>

#include <sys/kdebug.h>

static int copyio(int, user_addr_t, char *, vm_size_t, vm_size_t *, int);
static int copyio_phys(addr64_t, addr64_t, vm_size_t, int);

/*
 * Copy sizes bigger than this value will cause a kernel panic.
 *
 * Yes, this is an arbitrary fixed limit, but it's almost certainly
 * a programming error to be copying more than this amount between
 * user and wired kernel memory in a single invocation on this
 * platform.
 */
#define COPYSIZELIMIT_PANIC     (64*MB)

/*
 * The copy engine has the following characteristics
 *   - copyio() handles copies to/from user or kernel space
 *   - copypv() deals with physical or virtual addresses
 *
 * Readers familiar with the 32-bit kernel will expect Joe's thesis at this
 * point describing the full glory of the copy window implementation. In K64,
 * however, there is no need for windowing. Thanks to the vast shared address
 * space, the kernel has direct access to userspace and to physical memory.
 *
 * User virtual addresses are accessible provided the user's cr3 is loaded.
 * Physical addresses are accessible via the direct map and the PHYSMAP_PTOV()
 * translation.
 *
 * Copyin/out variants all boil done to just these 2 routines in locore.s which
 * provide fault-recoverable copying:
 */
extern int _bcopy(const void *, void *, vm_size_t);
extern int _bcopystr(const void *, void *, vm_size_t, vm_size_t *);
extern int _copyin_word(const char *src, uint64_t *dst, vm_size_t len);


/*
 * Types of copies:
 */
#define COPYIN		0	/* from user virtual to kernel virtual */
#define COPYOUT		1	/* from kernel virtual to user virtual */
#define COPYINSTR	2	/* string variant of copyout */
#define COPYINPHYS	3	/* from user virtual to kernel physical */
#define COPYOUTPHYS	4	/* from kernel physical to user virtual */
#define COPYINWORD	5	/* from user virtual to kernel virtual */

#if ENABLE_SMAPLOG
typedef struct {
	uint64_t 	timestamp;
	thread_t	thread;
	uintptr_t	cr4;
	uint8_t		cpuid;
	uint8_t		smap_state;
	uint8_t		copyio_active;
} smaplog_entry_t;

#define SMAPLOG_BUFFER_SIZE (50)
static smaplog_entry_t	smaplog_cbuf[SMAPLOG_BUFFER_SIZE];
static uint32_t		smaplog_head = 0;

static void
smaplog_add_entry(boolean_t enabling)
{
	uint32_t index = 0;
	thread_t thread = current_thread();

	do {
		index = smaplog_head;
	} while (!OSCompareAndSwap(index, (index + 1) % SMAPLOG_BUFFER_SIZE, &smaplog_head));

	assert(index < SMAPLOG_BUFFER_SIZE);
	assert(smaplog_head < SMAPLOG_BUFFER_SIZE);
	assert(thread);

	smaplog_cbuf[index].timestamp = mach_absolute_time();
	smaplog_cbuf[index].thread = thread;
	smaplog_cbuf[index].cpuid = cpu_number();
	smaplog_cbuf[index].cr4 = get_cr4();
	smaplog_cbuf[index].smap_state = enabling;
	smaplog_cbuf[index].copyio_active = (thread->machine.specFlags & CopyIOActive) ? 1 : 0;
}
#endif /* ENABLE_SMAPLOG */

extern boolean_t pmap_smap_enabled;
static inline void user_access_enable(void) {
	if (pmap_smap_enabled) {
		stac();
#if ENABLE_SMAPLOG
		smaplog_add_entry(TRUE);
#endif
	}
}
static inline void user_access_disable(void) {
	if (pmap_smap_enabled) {
		clac();
#if ENABLE_SMAPLOG
		smaplog_add_entry(FALSE);
#endif
	}
}

#if COPYIO_TRACE_ENABLED
#define COPYIO_TRACE(x, a, b, c, d, e) KERNEL_DEBUG_CONSTANT(x, a, b, c, d, e)
#else
#define COPYIO_TRACE(x, a, b, c, d, e) do { } while(0)
#endif

static int
copyio(int copy_type, user_addr_t user_addr, char *kernel_addr,
       vm_size_t nbytes, vm_size_t *lencopied, int use_kernel_map)
{
        thread_t	thread = current_thread();
	pmap_t		pmap;
	vm_size_t	bytes_copied;
	int		error = 0;
	boolean_t	istate = FALSE;
	boolean_t	recursive_CopyIOActive;
#if	COPYIO_TRACE_ENABLED
	int		debug_type = 0xeff70010;
	debug_type += (copy_type << 2);
#endif
	boolean_t nopagezero = thread->map->pmap->pagezero_accessible;

	assert(nbytes < COPYSIZELIMIT_PANIC);

	COPYIO_TRACE(debug_type | DBG_FUNC_START,
	    user_addr, kernel_addr, nbytes, use_kernel_map, 0);

	if (__improbable(nbytes == 0))
		goto out;

        pmap = thread->map->pmap;

	if (__improbable((copy_type != COPYINPHYS) && (copy_type != COPYOUTPHYS) && ((vm_offset_t)kernel_addr < VM_MIN_KERNEL_AND_KEXT_ADDRESS))) {
		panic("Invalid copy parameter, copy type: %d, kernel address: %p", copy_type, kernel_addr);
	}

	/* Sanity and security check for addresses to/from a user */

	if (__improbable(((pmap != kernel_pmap) && (use_kernel_map == 0)) &&
		((nbytes && (user_addr+nbytes <= user_addr)) || ((user_addr + nbytes) > vm_map_max(thread->map))))) {
		error = EFAULT;
		goto out;
	}

	/*
	 * If the no_shared_cr3 boot-arg is set (true), the kernel runs on 
	 * its own pmap and cr3 rather than the user's -- so that wild accesses
	 * from kernel or kexts can be trapped. So, during copyin and copyout,
	 * we need to switch back to the user's map/cr3. The thread is flagged
	 * "CopyIOActive" at this time so that if the thread is pre-empted,
	 * we will later restore the correct cr3.
	 */
	recursive_CopyIOActive = thread->machine.specFlags & CopyIOActive;

	boolean_t pdswitch = no_shared_cr3 || nopagezero;

	if (__improbable(pdswitch)) {
		istate = ml_set_interrupts_enabled(FALSE);
		if (nopagezero && pmap_pcid_ncpus) {
			pmap_pcid_activate(pmap, cpu_number(), TRUE, TRUE);
		} else if (get_cr3_base() != pmap->pm_cr3) {
			set_cr3_raw(pmap->pm_cr3);
		}
		thread->machine.specFlags |= CopyIOActive;
	} else {
		thread->machine.specFlags |= CopyIOActive;
	}

	user_access_enable();

#if DEVELOPMENT || DEBUG	
	/*
	 * Ensure that we're running on the target thread's cr3.
	 */
	if ((pmap != kernel_pmap) && !use_kernel_map &&
	    (get_cr3_base() != pmap->pm_cr3)) {
		panic("copyio(%d,%p,%p,%ld,%p,%d) cr3 is %p expects %p",
			copy_type, (void *)user_addr, kernel_addr, nbytes, lencopied, use_kernel_map,
			(void *) get_cr3_raw(), (void *) pmap->pm_cr3);
	}
#endif

	if (__improbable(pdswitch)) {
		(void) ml_set_interrupts_enabled(istate);
	}

	COPYIO_TRACE(0xeff70044 | DBG_FUNC_NONE, user_addr,
		     kernel_addr, nbytes, 0, 0);

        switch (copy_type) {

	case COPYIN:
	        error = _bcopy((const void *) user_addr,
				kernel_addr,
				nbytes);
		break;
			
	case COPYOUT:
	        error = _bcopy(kernel_addr,
				(void *) user_addr,
				nbytes);
		break;

	case COPYINPHYS:
	        error = _bcopy((const void *) user_addr,
				PHYSMAP_PTOV(kernel_addr),
				nbytes);
		break;

	case COPYOUTPHYS:
	        error = _bcopy((const void *) PHYSMAP_PTOV(kernel_addr),
				(void *) user_addr,
				nbytes);
		break;

	case COPYINWORD:
		error = _copyin_word((const void *) user_addr,
				(void *) kernel_addr,
				nbytes);
		break;

	case COPYINSTR:
	        error = _bcopystr((const void *) user_addr,
				kernel_addr,
				(int) nbytes,
				&bytes_copied);

		/*
		 * lencopied should be updated on success
		 * or ENAMETOOLONG...  but not EFAULT
		 */
		if (error != EFAULT)
		        *lencopied = bytes_copied;

		if (error) {
#if KDEBUG
		        nbytes = *lencopied;
#endif
		        break;
		}
		if (*(kernel_addr + bytes_copied - 1) == 0) {
		        /*
			 * we found a NULL terminator... we're done
			 */
#if KDEBUG
		        nbytes = *lencopied;
#endif
			break;
		} else {
		        /*
			 * no more room in the buffer and we haven't
			 * yet come across a NULL terminator
			 */
#if KDEBUG
		        nbytes = *lencopied;
#endif
		        error = ENAMETOOLONG;
			break;
		}
	}

	user_access_disable();

	if (__improbable(pdswitch)) {
		istate = ml_set_interrupts_enabled(FALSE);
		if  (!recursive_CopyIOActive && (get_cr3_raw() != kernel_pmap->pm_cr3)) {
			if (nopagezero && pmap_pcid_ncpus) {
				pmap_pcid_activate(pmap, cpu_number(), TRUE, FALSE);
			} else {
				set_cr3_raw(kernel_pmap->pm_cr3);
			}
		}

		if (!recursive_CopyIOActive) {
			thread->machine.specFlags &= ~CopyIOActive;
		}
		(void) ml_set_interrupts_enabled(istate);
	} else if (!recursive_CopyIOActive) {
		thread->machine.specFlags &= ~CopyIOActive;
	}

out:
	COPYIO_TRACE(debug_type | DBG_FUNC_END, user_addr, kernel_addr, nbytes, error, 0);

	return (error);
}


static int
copyio_phys(addr64_t source, addr64_t sink, vm_size_t csize, int which)
{
        char	    *paddr;
	user_addr_t vaddr;
	int         ctype;

	if (which & cppvPsnk) {
		paddr  = (char *)sink;
	        vaddr  = (user_addr_t)source;
		ctype  = COPYINPHYS;
	} else {
	        paddr  = (char *)source;
		vaddr  = (user_addr_t)sink;
		ctype  = COPYOUTPHYS;
	}
	return copyio(ctype, vaddr, paddr, csize, NULL, which & cppvKmap);
}

int
copyinmsg(const user_addr_t user_addr, char *kernel_addr, mach_msg_size_t nbytes)
{
    return copyio(COPYIN, user_addr, kernel_addr, nbytes, NULL, 0);
}    

int
copyin(const user_addr_t user_addr, char *kernel_addr, vm_size_t nbytes)
{
    return copyio(COPYIN, user_addr, kernel_addr, nbytes, NULL, 0);
}

/*
 * copyin_word
 * Read an aligned value from userspace as a single memory transaction.
 * This function supports userspace synchronization features
 */
int
copyin_word(const user_addr_t user_addr, uint64_t *kernel_addr, vm_size_t nbytes)
{
	/* Verify sizes */
	if ((nbytes != 4) && (nbytes != 8))
		return EINVAL;

	/* Test alignment */
	if (user_addr & (nbytes - 1))
		return EINVAL;
	return copyio(COPYINWORD, user_addr, (char *)(uintptr_t)kernel_addr, nbytes, NULL, 0);
}

int
copyinstr(const user_addr_t user_addr,  char *kernel_addr, vm_size_t nbytes, vm_size_t *lencopied)
{
    *lencopied = 0;

    return copyio(COPYINSTR, user_addr, kernel_addr, nbytes, lencopied, 0);
}

int
copyoutmsg(const char *kernel_addr, user_addr_t user_addr, mach_msg_size_t nbytes)
{
    return copyio(COPYOUT, user_addr, (char *)(uintptr_t)kernel_addr, nbytes, NULL, 0);
}

int
copyout(const void *kernel_addr, user_addr_t user_addr, vm_size_t nbytes)
{
    return copyio(COPYOUT, user_addr, (char *)(uintptr_t)kernel_addr, nbytes, NULL, 0);
}


kern_return_t
copypv(addr64_t src64, addr64_t snk64, unsigned int size, int which)
{
	unsigned int lop, csize;
	int bothphys = 0;
	
	KERNEL_DEBUG(0xeff7004c | DBG_FUNC_START, (unsigned)src64,
		     (unsigned)snk64, size, which, 0);

	if ((which & (cppvPsrc | cppvPsnk)) == 0 )				/* Make sure that only one is virtual */
		panic("copypv: no more than 1 parameter may be virtual\n");	/* Not allowed */

	if ((which & (cppvPsrc | cppvPsnk)) == (cppvPsrc | cppvPsnk))
	        bothphys = 1;							/* both are physical */

	while (size) {
	  
	        if (bothphys) {
		        lop = (unsigned int)(PAGE_SIZE - (snk64 & (PAGE_SIZE - 1)));		/* Assume sink smallest */

			if (lop > (unsigned int)(PAGE_SIZE - (src64 & (PAGE_SIZE - 1))))
			        lop = (unsigned int)(PAGE_SIZE - (src64 & (PAGE_SIZE - 1)));	/* No, source is smaller */
		} else {
		        /*
			 * only need to compute the resid for the physical page
			 * address... we don't care about where we start/finish in
			 * the virtual since we just call the normal copyin/copyout
			 */
		        if (which & cppvPsrc)
			        lop = (unsigned int)(PAGE_SIZE - (src64 & (PAGE_SIZE - 1)));
			else
			        lop = (unsigned int)(PAGE_SIZE - (snk64 & (PAGE_SIZE - 1)));
		}
		csize = size;						/* Assume we can copy it all */
		if (lop < size)
		        csize = lop;					/* Nope, we can't do it all */
#if 0		
		/*
		 * flush_dcache64 is currently a nop on the i386... 
		 * it's used when copying to non-system memory such
		 * as video capture cards... on PPC there was a need
		 * to flush due to how we mapped this memory... not
		 * sure if it's needed on i386.
		 */
		if (which & cppvFsrc)
		        flush_dcache64(src64, csize, 1);		/* If requested, flush source before move */
		if (which & cppvFsnk)
		        flush_dcache64(snk64, csize, 1);		/* If requested, flush sink before move */
#endif
		if (bothphys)
		        bcopy_phys(src64, snk64, csize);		/* Do a physical copy, virtually */
		else {
		        if (copyio_phys(src64, snk64, csize, which))
			        return (KERN_FAILURE);
		}
#if 0
		if (which & cppvFsrc)
		        flush_dcache64(src64, csize, 1);	/* If requested, flush source after move */
		if (which & cppvFsnk)
		        flush_dcache64(snk64, csize, 1);	/* If requested, flush sink after move */
#endif
		size   -= csize;					/* Calculate what is left */
		snk64 += csize;					/* Bump sink to next physical address */
		src64 += csize;					/* Bump source to next physical address */
	}
	KERNEL_DEBUG(0xeff7004c | DBG_FUNC_END, (unsigned)src64,
		     (unsigned)snk64, size, which, 0);

	return KERN_SUCCESS;
}
Commit	Line	Data
6d2010ae	1	/*
39037602	2	* Copyright (c) 2009-2016 Apple Inc. All rights reserved.
6d2010ae A	3	*
	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
	5	*
	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
	25	*
	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
	27	*/
	28	#include <mach_assert.h>
	29
	30	#include <sys/errno.h>
	31	#include <i386/param.h>
	32	#include <i386/misc_protos.h>
	33	#include <i386/cpu_data.h>
	34	#include <i386/machine_routines.h>
	35	#include <i386/cpuid.h>
	36	#include <i386/vmx.h>
	37	#include <vm/pmap.h>
	38	#include <vm/vm_map.h>
	39	#include <vm/vm_kern.h>
	40	#include <vm/vm_fault.h>
	41
	42	#include <sys/kdebug.h>
	43
	44	static int copyio(int, user_addr_t, char , vm_size_t, vm_size_t , int);
	45	static int copyio_phys(addr64_t, addr64_t, vm_size_t, int);
	46
3e170ce0 A	47	/*
	48	* Copy sizes bigger than this value will cause a kernel panic.
	49	*
	50	* Yes, this is an arbitrary fixed limit, but it's almost certainly
	51	* a programming error to be copying more than this amount between
	52	* user and wired kernel memory in a single invocation on this
	53	* platform.
	54	*/
	55	#define COPYSIZELIMIT_PANIC (64*MB)
	56
6d2010ae A	57	/*
	58	* The copy engine has the following characteristics
	59	* - copyio() handles copies to/from user or kernel space
	60	* - copypv() deals with physical or virtual addresses
	61	*
	62	* Readers familiar with the 32-bit kernel will expect Joe's thesis at this
	63	* point describing the full glory of the copy window implementation. In K64,
	64	* however, there is no need for windowing. Thanks to the vast shared address
	65	* space, the kernel has direct access to userspace and to physical memory.
	66	*
	67	* User virtual addresses are accessible provided the user's cr3 is loaded.
	68	* Physical addresses are accessible via the direct map and the PHYSMAP_PTOV()
	69	* translation.
	70	*
	71	* Copyin/out variants all boil done to just these 2 routines in locore.s which
	72	* provide fault-recoverable copying:
	73	*/
	74	extern int _bcopy(const void , void , vm_size_t);
	75	extern int _bcopystr(const void , void , vm_size_t, vm_size_t *);
39037602	76	extern int _copyin_word(const char src, uint64_t dst, vm_size_t len);
6d2010ae A	77
	78
	79	/*
	80	* Types of copies:
	81	*/
	82	#define COPYIN 0 /* from user virtual to kernel virtual */
	83	#define COPYOUT 1 /* from kernel virtual to user virtual */
	84	#define COPYINSTR 2 /* string variant of copyout */
	85	#define COPYINPHYS 3 /* from user virtual to kernel physical */
	86	#define COPYOUTPHYS 4 /* from kernel physical to user virtual */
39037602	87	#define COPYINWORD 5 /* from user virtual to kernel virtual */
6d2010ae	88
39037602	89	#if ENABLE_SMAPLOG
04b8595b A	90	typedef struct {
	91	uint64_t timestamp;
	92	thread_t thread;
	93	uintptr_t cr4;
	94	uint8_t cpuid;
	95	uint8_t smap_state;
	96	uint8_t copyio_active;
	97	} smaplog_entry_t;
	98
	99	#define SMAPLOG_BUFFER_SIZE (50)
	100	static smaplog_entry_t smaplog_cbuf[SMAPLOG_BUFFER_SIZE];
	101	static uint32_t smaplog_head = 0;
	102
	103	static void
	104	smaplog_add_entry(boolean_t enabling)
	105	{
	106	uint32_t index = 0;
	107	thread_t thread = current_thread();
	108
	109	do {
	110	index = smaplog_head;
	111	} while (!OSCompareAndSwap(index, (index + 1) % SMAPLOG_BUFFER_SIZE, &smaplog_head));
	112
	113	assert(index < SMAPLOG_BUFFER_SIZE);
	114	assert(smaplog_head < SMAPLOG_BUFFER_SIZE);
	115	assert(thread);
	116
	117	smaplog_cbuf[index].timestamp = mach_absolute_time();
	118	smaplog_cbuf[index].thread = thread;
	119	smaplog_cbuf[index].cpuid = cpu_number();
	120	smaplog_cbuf[index].cr4 = get_cr4();
	121	smaplog_cbuf[index].smap_state = enabling;
	122	smaplog_cbuf[index].copyio_active = (thread->machine.specFlags & CopyIOActive) ? 1 : 0;
	123	}
39037602	124	#endif /* ENABLE_SMAPLOG */
04b8595b A	125
	126	extern boolean_t pmap_smap_enabled;
	127	static inline void user_access_enable(void) {
	128	if (pmap_smap_enabled) {
	129	stac();
39037602	130	#if ENABLE_SMAPLOG
04b8595b A	131	smaplog_add_entry(TRUE);
	132	#endif
	133	}
	134	}
	135	static inline void user_access_disable(void) {
	136	if (pmap_smap_enabled) {
	137	clac();
39037602	138	#if ENABLE_SMAPLOG
04b8595b A	139	smaplog_add_entry(FALSE);
	140	#endif
	141	}
	142	}
a1c7dba1	143
39037602 A	144	#if COPYIO_TRACE_ENABLED
	145	#define COPYIO_TRACE(x, a, b, c, d, e) KERNEL_DEBUG_CONSTANT(x, a, b, c, d, e)
	146	#else
	147	#define COPYIO_TRACE(x, a, b, c, d, e) do { } while(0)
	148	#endif
	149
6d2010ae A	150	static int
	151	copyio(int copy_type, user_addr_t user_addr, char *kernel_addr,
	152	vm_size_t nbytes, vm_size_t *lencopied, int use_kernel_map)
	153	{
39037602	154	thread_t thread = current_thread();
6d2010ae A	155	pmap_t pmap;
	156	vm_size_t bytes_copied;
	157	int error = 0;
	158	boolean_t istate = FALSE;
	159	boolean_t recursive_CopyIOActive;
39037602	160	#if COPYIO_TRACE_ENABLED
6d2010ae A	161	int debug_type = 0xeff70010;
	162	debug_type += (copy_type << 2);
	163	#endif
39037602	164	boolean_t nopagezero = thread->map->pmap->pagezero_accessible;
6d2010ae	165
3e170ce0 A	166	assert(nbytes < COPYSIZELIMIT_PANIC);
3e170ce0 A	167
39037602 A	168	COPYIO_TRACE(debug_type \| DBG_FUNC_START,
39037602 A	169	user_addr, kernel_addr, nbytes, use_kernel_map, 0);
6d2010ae	170
39037602	171	if (__improbable(nbytes == 0))
6d2010ae A	172	goto out;
	173
	174	pmap = thread->map->pmap;
	175
39037602	176	if (__improbable((copy_type != COPYINPHYS) && (copy_type != COPYOUTPHYS) && ((vm_offset_t)kernel_addr < VM_MIN_KERNEL_AND_KEXT_ADDRESS))) {
6d2010ae A	177	panic("Invalid copy parameter, copy type: %d, kernel address: %p", copy_type, kernel_addr);
	178	}
	179
	180	/* Sanity and security check for addresses to/from a user */
	181
39037602 A	182	if (__improbable(((pmap != kernel_pmap) && (use_kernel_map == 0)) &&
39037602 A	183	((nbytes && (user_addr+nbytes <= user_addr)) \|\| ((user_addr + nbytes) > vm_map_max(thread->map))))) {
6d2010ae A	184	error = EFAULT;
	185	goto out;
	186	}
	187
	188	/*
	189	* If the no_shared_cr3 boot-arg is set (true), the kernel runs on
	190	* its own pmap and cr3 rather than the user's -- so that wild accesses
	191	* from kernel or kexts can be trapped. So, during copyin and copyout,
	192	* we need to switch back to the user's map/cr3. The thread is flagged
	193	* "CopyIOActive" at this time so that if the thread is pre-empted,
	194	* we will later restore the correct cr3.
	195	*/
	196	recursive_CopyIOActive = thread->machine.specFlags & CopyIOActive;
39037602 A	197
	198	boolean_t pdswitch = no_shared_cr3 \|\| nopagezero;
	199
	200	if (__improbable(pdswitch)) {
6d2010ae	201	istate = ml_set_interrupts_enabled(FALSE);
39037602 A	202	if (nopagezero && pmap_pcid_ncpus) {
	203	pmap_pcid_activate(pmap, cpu_number(), TRUE, TRUE);
	204	} else if (get_cr3_base() != pmap->pm_cr3) {
6d2010ae	205	set_cr3_raw(pmap->pm_cr3);
39037602 A	206	}
	207	thread->machine.specFlags \|= CopyIOActive;
	208	} else {
	209	thread->machine.specFlags \|= CopyIOActive;
6d2010ae A	210	}
6d2010ae A	211
39037602 A	212	user_access_enable();
	213
	214	#if DEVELOPMENT \|\| DEBUG
6d2010ae A	215	/*
	216	* Ensure that we're running on the target thread's cr3.
	217	*/
	218	if ((pmap != kernel_pmap) && !use_kernel_map &&
	219	(get_cr3_base() != pmap->pm_cr3)) {
	220	panic("copyio(%d,%p,%p,%ld,%p,%d) cr3 is %p expects %p",
	221	copy_type, (void *)user_addr, kernel_addr, nbytes, lencopied, use_kernel_map,
	222	(void ) get_cr3_raw(), (void ) pmap->pm_cr3);
	223	}
39037602 A	224	#endif
	225
	226	if (__improbable(pdswitch)) {
6d2010ae	227	(void) ml_set_interrupts_enabled(istate);
39037602	228	}
6d2010ae	229
39037602 A	230	COPYIO_TRACE(0xeff70044 \| DBG_FUNC_NONE, user_addr,
39037602 A	231	kernel_addr, nbytes, 0, 0);
6d2010ae A	232
	233	switch (copy_type) {
	234
	235	case COPYIN:
	236	error = _bcopy((const void *) user_addr,
	237	kernel_addr,
	238	nbytes);
	239	break;
	240
	241	case COPYOUT:
	242	error = _bcopy(kernel_addr,
	243	(void *) user_addr,
	244	nbytes);
	245	break;
	246
	247	case COPYINPHYS:
	248	error = _bcopy((const void *) user_addr,
	249	PHYSMAP_PTOV(kernel_addr),
	250	nbytes);
	251	break;
	252
	253	case COPYOUTPHYS:
	254	error = _bcopy((const void *) PHYSMAP_PTOV(kernel_addr),
	255	(void *) user_addr,
	256	nbytes);
	257	break;
	258
39037602 A	259	case COPYINWORD:
	260	error = _copyin_word((const void *) user_addr,
	261	(void *) kernel_addr,
	262	nbytes);
	263	break;
	264
6d2010ae A	265	case COPYINSTR:
	266	error = _bcopystr((const void *) user_addr,
	267	kernel_addr,
	268	(int) nbytes,
	269	&bytes_copied);
	270
	271	/*
	272	* lencopied should be updated on success
	273	* or ENAMETOOLONG... but not EFAULT
	274	*/
	275	if (error != EFAULT)
	276	*lencopied = bytes_copied;
	277
	278	if (error) {
	279	#if KDEBUG
	280	nbytes = *lencopied;
	281	#endif
	282	break;
	283	}
	284	if (*(kernel_addr + bytes_copied - 1) == 0) {
	285	/*
	286	* we found a NULL terminator... we're done
	287	*/
	288	#if KDEBUG
	289	nbytes = *lencopied;
	290	#endif
	291	break;
	292	} else {
	293	/*
	294	* no more room in the buffer and we haven't
	295	* yet come across a NULL terminator
	296	*/
	297	#if KDEBUG
	298	nbytes = *lencopied;
	299	#endif
	300	error = ENAMETOOLONG;
	301	break;
	302	}
6d2010ae A	303	}
6d2010ae A	304
04b8595b	305	user_access_disable();
39037602 A	306
39037602 A	307	if (__improbable(pdswitch)) {
6d2010ae	308	istate = ml_set_interrupts_enabled(FALSE);
39037602 A	309	if (!recursive_CopyIOActive && (get_cr3_raw() != kernel_pmap->pm_cr3)) {
	310	if (nopagezero && pmap_pcid_ncpus) {
	311	pmap_pcid_activate(pmap, cpu_number(), TRUE, FALSE);
	312	} else {
	313	set_cr3_raw(kernel_pmap->pm_cr3);
	314	}
	315	}
	316
	317	if (!recursive_CopyIOActive) {
	318	thread->machine.specFlags &= ~CopyIOActive;
	319	}
6d2010ae	320	(void) ml_set_interrupts_enabled(istate);
39037602 A	321	} else if (!recursive_CopyIOActive) {
39037602 A	322	thread->machine.specFlags &= ~CopyIOActive;
6d2010ae A	323	}
	324
	325	out:
39037602	326	COPYIO_TRACE(debug_type \| DBG_FUNC_END, user_addr, kernel_addr, nbytes, error, 0);
6d2010ae A	327
	328	return (error);
	329	}
	330
	331
	332	static int
	333	copyio_phys(addr64_t source, addr64_t sink, vm_size_t csize, int which)
	334	{
	335	char *paddr;
	336	user_addr_t vaddr;
	337	int ctype;
	338
	339	if (which & cppvPsnk) {
	340	paddr = (char *)sink;
	341	vaddr = (user_addr_t)source;
	342	ctype = COPYINPHYS;
	343	} else {
	344	paddr = (char *)source;
	345	vaddr = (user_addr_t)sink;
	346	ctype = COPYOUTPHYS;
	347	}
	348	return copyio(ctype, vaddr, paddr, csize, NULL, which & cppvKmap);
	349	}
	350
	351	int
	352	copyinmsg(const user_addr_t user_addr, char *kernel_addr, mach_msg_size_t nbytes)
	353	{
	354	return copyio(COPYIN, user_addr, kernel_addr, nbytes, NULL, 0);
	355	}
	356
	357	int
	358	copyin(const user_addr_t user_addr, char *kernel_addr, vm_size_t nbytes)
	359	{
	360	return copyio(COPYIN, user_addr, kernel_addr, nbytes, NULL, 0);
	361	}
	362
39037602 A	363	/*
	364	* copyin_word
	365	* Read an aligned value from userspace as a single memory transaction.
	366	* This function supports userspace synchronization features
	367	*/
	368	int
	369	copyin_word(const user_addr_t user_addr, uint64_t *kernel_addr, vm_size_t nbytes)
	370	{
	371	/* Verify sizes */
	372	if ((nbytes != 4) && (nbytes != 8))
	373	return EINVAL;
	374
	375	/* Test alignment */
	376	if (user_addr & (nbytes - 1))
	377	return EINVAL;
	378	return copyio(COPYINWORD, user_addr, (char *)(uintptr_t)kernel_addr, nbytes, NULL, 0);
	379	}
	380
6d2010ae A	381	int
	382	copyinstr(const user_addr_t user_addr, char kernel_addr, vm_size_t nbytes, vm_size_t lencopied)
	383	{
	384	*lencopied = 0;
	385
	386	return copyio(COPYINSTR, user_addr, kernel_addr, nbytes, lencopied, 0);
	387	}
	388
	389	int
	390	copyoutmsg(const char *kernel_addr, user_addr_t user_addr, mach_msg_size_t nbytes)
	391	{
	392	return copyio(COPYOUT, user_addr, (char *)(uintptr_t)kernel_addr, nbytes, NULL, 0);
	393	}
	394
	395	int
	396	copyout(const void *kernel_addr, user_addr_t user_addr, vm_size_t nbytes)
	397	{
	398	return copyio(COPYOUT, user_addr, (char *)(uintptr_t)kernel_addr, nbytes, NULL, 0);
	399	}
	400
	401
	402	kern_return_t
	403	copypv(addr64_t src64, addr64_t snk64, unsigned int size, int which)
	404	{
	405	unsigned int lop, csize;
	406	int bothphys = 0;
	407
	408	KERNEL_DEBUG(0xeff7004c \| DBG_FUNC_START, (unsigned)src64,
	409	(unsigned)snk64, size, which, 0);
	410
	411	if ((which & (cppvPsrc \| cppvPsnk)) == 0 ) /* Make sure that only one is virtual */
	412	panic("copypv: no more than 1 parameter may be virtual\n"); /* Not allowed */
	413
	414	if ((which & (cppvPsrc \| cppvPsnk)) == (cppvPsrc \| cppvPsnk))
	415	bothphys = 1; /* both are physical */
	416
	417	while (size) {
	418
	419	if (bothphys) {
	420	lop = (unsigned int)(PAGE_SIZE - (snk64 & (PAGE_SIZE - 1))); /* Assume sink smallest */
	421
	422	if (lop > (unsigned int)(PAGE_SIZE - (src64 & (PAGE_SIZE - 1))))
	423	lop = (unsigned int)(PAGE_SIZE - (src64 & (PAGE_SIZE - 1))); /* No, source is smaller */
	424	} else {
	425	/*
	426	* only need to compute the resid for the physical page
	427	* address... we don't care about where we start/finish in
	428	* the virtual since we just call the normal copyin/copyout
	429	*/
	430	if (which & cppvPsrc)
	431	lop = (unsigned int)(PAGE_SIZE - (src64 & (PAGE_SIZE - 1)));
	432	else
	433	lop = (unsigned int)(PAGE_SIZE - (snk64 & (PAGE_SIZE - 1)));
	434	}
	435	csize = size; /* Assume we can copy it all */
	436	if (lop < size)
	437	csize = lop; /* Nope, we can't do it all */
	438	#if 0
	439	/*
	440	* flush_dcache64 is currently a nop on the i386...
	441	* it's used when copying to non-system memory such
	442	* as video capture cards... on PPC there was a need
	443	* to flush due to how we mapped this memory... not
	444	* sure if it's needed on i386.
445	*/
446	if (which & cppvFsrc)
447	flush_dcache64(src64, csize, 1); /* If requested, flush source before move */
448	if (which & cppvFsnk)
449	flush_dcache64(snk64, csize, 1); /* If requested, flush sink before move */
450	#endif
451	if (bothphys)
452	bcopy_phys(src64, snk64, csize); /* Do a physical copy, virtually */
453	else {
454	if (copyio_phys(src64, snk64, csize, which))
455	return (KERN_FAILURE);
456	}
457	#if 0
458	if (which & cppvFsrc)
459	flush_dcache64(src64, csize, 1); /* If requested, flush source after move */
460	if (which & cppvFsnk)
461	flush_dcache64(snk64, csize, 1); /* If requested, flush sink after move */
462	#endif
463	size -= csize; /* Calculate what is left */
464	snk64 += csize; /* Bump sink to next physical address */
465	src64 += csize; /* Bump source to next physical address */
466	}
467	KERNEL_DEBUG(0xeff7004c \| DBG_FUNC_END, (unsigned)src64,
468	(unsigned)snk64, size, which, 0);
469
470	return KERN_SUCCESS;
471	}