[qemu.git] / bsd-user / mmap.c

/*
 *  mmap support for qemu
 *
 *  Copyright (c) 2003 - 2008 Fabrice Bellard
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
 */
#include "qemu/osdep.h"
#include <sys/mman.h>

#include "qemu.h"
#include "qemu-common.h"
#include "bsd-mman.h"

//#define DEBUG_MMAP

#if defined(CONFIG_USE_NPTL)
pthread_mutex_t mmap_mutex;
static int __thread mmap_lock_count;

void mmap_lock(void)
{
    if (mmap_lock_count++ == 0) {
        pthread_mutex_lock(&mmap_mutex);
    }
}

void mmap_unlock(void)
{
    if (--mmap_lock_count == 0) {
        pthread_mutex_unlock(&mmap_mutex);
    }
}

/* Grab lock to make sure things are in a consistent state after fork().  */
void mmap_fork_start(void)
{
    if (mmap_lock_count)
        abort();
    pthread_mutex_lock(&mmap_mutex);
}

void mmap_fork_end(int child)
{
    if (child)
        pthread_mutex_init(&mmap_mutex, NULL);
    else
        pthread_mutex_unlock(&mmap_mutex);
}
#else
/* We aren't threadsafe to start with, so no need to worry about locking.  */
void mmap_lock(void)
{
}

void mmap_unlock(void)
{
}
#endif

/* NOTE: all the constants are the HOST ones, but addresses are target. */
int target_mprotect(abi_ulong start, abi_ulong len, int prot)
{
    abi_ulong end, host_start, host_end, addr;
    int prot1, ret;

#ifdef DEBUG_MMAP
    printf("mprotect: start=0x" TARGET_FMT_lx
           " len=0x" TARGET_FMT_lx " prot=%c%c%c\n", start, len,
           prot & PROT_READ ? 'r' : '-',
           prot & PROT_WRITE ? 'w' : '-',
           prot & PROT_EXEC ? 'x' : '-');
#endif

    if ((start & ~TARGET_PAGE_MASK) != 0)
        return -EINVAL;
    len = TARGET_PAGE_ALIGN(len);
    end = start + len;
    if (end < start)
        return -EINVAL;
    prot &= PROT_READ | PROT_WRITE | PROT_EXEC;
    if (len == 0)
        return 0;

    mmap_lock();
    host_start = start & qemu_host_page_mask;
    host_end = HOST_PAGE_ALIGN(end);
    if (start > host_start) {
        /* handle host page containing start */
        prot1 = prot;
        for(addr = host_start; addr < start; addr += TARGET_PAGE_SIZE) {
            prot1 |= page_get_flags(addr);
        }
        if (host_end == host_start + qemu_host_page_size) {
            for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
                prot1 |= page_get_flags(addr);
            }
            end = host_end;
        }
        ret = mprotect(g2h(host_start), qemu_host_page_size, prot1 & PAGE_BITS);
        if (ret != 0)
            goto error;
        host_start += qemu_host_page_size;
    }
    if (end < host_end) {
        prot1 = prot;
        for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
            prot1 |= page_get_flags(addr);
        }
        ret = mprotect(g2h(host_end - qemu_host_page_size), qemu_host_page_size,
                       prot1 & PAGE_BITS);
        if (ret != 0)
            goto error;
        host_end -= qemu_host_page_size;
    }

    /* handle the pages in the middle */
    if (host_start < host_end) {
        ret = mprotect(g2h(host_start), host_end - host_start, prot);
        if (ret != 0)
            goto error;
    }
    page_set_flags(start, start + len, prot | PAGE_VALID);
    mmap_unlock();
    return 0;
error:
    mmap_unlock();
    return ret;
}

/* map an incomplete host page */
static int mmap_frag(abi_ulong real_start,
                     abi_ulong start, abi_ulong end,
                     int prot, int flags, int fd, abi_ulong offset)
{
    abi_ulong real_end, addr;
    void *host_start;
    int prot1, prot_new;

    real_end = real_start + qemu_host_page_size;
    host_start = g2h(real_start);

    /* get the protection of the target pages outside the mapping */
    prot1 = 0;
    for(addr = real_start; addr < real_end; addr++) {
        if (addr < start || addr >= end)
            prot1 |= page_get_flags(addr);
    }

    if (prot1 == 0) {
        /* no page was there, so we allocate one */
        void *p = mmap(host_start, qemu_host_page_size, prot,
                       flags | MAP_ANON, -1, 0);
        if (p == MAP_FAILED)
            return -1;
        prot1 = prot;
    }
    prot1 &= PAGE_BITS;

    prot_new = prot | prot1;
    if (!(flags & MAP_ANON)) {
        /* msync() won't work here, so we return an error if write is
           possible while it is a shared mapping */
        if ((flags & TARGET_BSD_MAP_FLAGMASK) == MAP_SHARED &&
            (prot & PROT_WRITE))
            return -1;

        /* adjust protection to be able to read */
        if (!(prot1 & PROT_WRITE))
            mprotect(host_start, qemu_host_page_size, prot1 | PROT_WRITE);

        /* read the corresponding file data */
        pread(fd, g2h(start), end - start, offset);

        /* put final protection */
        if (prot_new != (prot1 | PROT_WRITE))
            mprotect(host_start, qemu_host_page_size, prot_new);
    } else {
        /* just update the protection */
        if (prot_new != prot1) {
            mprotect(host_start, qemu_host_page_size, prot_new);
        }
    }
    return 0;
}

#if defined(__CYGWIN__)
/* Cygwin doesn't have a whole lot of address space.  */
static abi_ulong mmap_next_start = 0x18000000;
#else
static abi_ulong mmap_next_start = 0x40000000;
#endif

unsigned long last_brk;

/* find a free memory area of size 'size'. The search starts at
   'start'. If 'start' == 0, then a default start address is used.
   Return -1 if error.
*/
/* page_init() marks pages used by the host as reserved to be sure not
   to use them. */
static abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size)
{
    abi_ulong addr, addr1, addr_start;
    int prot;
    unsigned long new_brk;

    new_brk = (unsigned long)sbrk(0);
    if (last_brk && last_brk < new_brk && last_brk == (target_ulong)last_brk) {
        /* This is a hack to catch the host allocating memory with brk().
           If it uses mmap then we loose.
           FIXME: We really want to avoid the host allocating memory in
           the first place, and maybe leave some slack to avoid switching
           to mmap.  */
        page_set_flags(last_brk & TARGET_PAGE_MASK,
                       TARGET_PAGE_ALIGN(new_brk),
                       PAGE_RESERVED);
    }
    last_brk = new_brk;

    size = HOST_PAGE_ALIGN(size);
    start = start & qemu_host_page_mask;
    addr = start;
    if (addr == 0)
        addr = mmap_next_start;
    addr_start = addr;
    for(;;) {
        prot = 0;
        for(addr1 = addr; addr1 < (addr + size); addr1 += TARGET_PAGE_SIZE) {
            prot |= page_get_flags(addr1);
        }
        if (prot == 0)
            break;
        addr += qemu_host_page_size;
        /* we found nothing */
        if (addr == addr_start)
            return (abi_ulong)-1;
    }
    if (start == 0)
        mmap_next_start = addr + size;
    return addr;
}

/* NOTE: all the constants are the HOST ones */
abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
                     int flags, int fd, abi_ulong offset)
{
    abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len;
    unsigned long host_start;

    mmap_lock();
#ifdef DEBUG_MMAP
    {
        printf("mmap: start=0x" TARGET_FMT_lx
               " len=0x" TARGET_FMT_lx " prot=%c%c%c flags=",
               start, len,
               prot & PROT_READ ? 'r' : '-',
               prot & PROT_WRITE ? 'w' : '-',
               prot & PROT_EXEC ? 'x' : '-');
        if (flags & MAP_FIXED)
            printf("MAP_FIXED ");
        if (flags & MAP_ANON)
            printf("MAP_ANON ");
        switch(flags & TARGET_BSD_MAP_FLAGMASK) {
        case MAP_PRIVATE:
            printf("MAP_PRIVATE ");
            break;
        case MAP_SHARED:
            printf("MAP_SHARED ");
            break;
        default:
            printf("[MAP_FLAGMASK=0x%x] ", flags & TARGET_BSD_MAP_FLAGMASK);
            break;
        }
        printf("fd=%d offset=" TARGET_FMT_lx "\n", fd, offset);
    }
#endif

    if (offset & ~TARGET_PAGE_MASK) {
        errno = EINVAL;
        goto fail;
    }

    len = TARGET_PAGE_ALIGN(len);
    if (len == 0)
        goto the_end;
    real_start = start & qemu_host_page_mask;

    if (!(flags & MAP_FIXED)) {
        abi_ulong mmap_start;
        void *p;
        host_offset = offset & qemu_host_page_mask;
        host_len = len + offset - host_offset;
        host_len = HOST_PAGE_ALIGN(host_len);
        mmap_start = mmap_find_vma(real_start, host_len);
        if (mmap_start == (abi_ulong)-1) {
            errno = ENOMEM;
            goto fail;
        }
        /* Note: we prefer to control the mapping address. It is
           especially important if qemu_host_page_size >
           qemu_real_host_page_size */
        p = mmap(g2h(mmap_start),
                 host_len, prot, flags | MAP_FIXED, fd, host_offset);
        if (p == MAP_FAILED)
            goto fail;
        /* update start so that it points to the file position at 'offset' */
        host_start = (unsigned long)p;
        if (!(flags & MAP_ANON))
            host_start += offset - host_offset;
        start = h2g(host_start);
    } else {
        int flg;
        target_ulong addr;

        if (start & ~TARGET_PAGE_MASK) {
            errno = EINVAL;
            goto fail;
        }
        end = start + len;
        real_end = HOST_PAGE_ALIGN(end);

        for(addr = real_start; addr < real_end; addr += TARGET_PAGE_SIZE) {
            flg = page_get_flags(addr);
            if (flg & PAGE_RESERVED) {
                errno = ENXIO;
                goto fail;
            }
        }

        /* worst case: we cannot map the file because the offset is not
           aligned, so we read it */
        if (!(flags & MAP_ANON) &&
            (offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) {
            /* msync() won't work here, so we return an error if write is
               possible while it is a shared mapping */
            if ((flags & TARGET_BSD_MAP_FLAGMASK) == MAP_SHARED &&
                (prot & PROT_WRITE)) {
                errno = EINVAL;
                goto fail;
            }
            retaddr = target_mmap(start, len, prot | PROT_WRITE,
                                  MAP_FIXED | MAP_PRIVATE | MAP_ANON,
                                  -1, 0);
            if (retaddr == -1)
                goto fail;
            pread(fd, g2h(start), len, offset);
            if (!(prot & PROT_WRITE)) {
                ret = target_mprotect(start, len, prot);
                if (ret != 0) {
                    start = ret;
                    goto the_end;
                }
            }
            goto the_end;
        }

        /* handle the start of the mapping */
        if (start > real_start) {
            if (real_end == real_start + qemu_host_page_size) {
                /* one single host page */
                ret = mmap_frag(real_start, start, end,
                                prot, flags, fd, offset);
                if (ret == -1)
                    goto fail;
                goto the_end1;
            }
            ret = mmap_frag(real_start, start, real_start + qemu_host_page_size,
                            prot, flags, fd, offset);
            if (ret == -1)
                goto fail;
            real_start += qemu_host_page_size;
        }
        /* handle the end of the mapping */
        if (end < real_end) {
            ret = mmap_frag(real_end - qemu_host_page_size,
                            real_end - qemu_host_page_size, real_end,
                            prot, flags, fd,
                            offset + real_end - qemu_host_page_size - start);
            if (ret == -1)
                goto fail;
            real_end -= qemu_host_page_size;
        }

        /* map the middle (easier) */
        if (real_start < real_end) {
            void *p;
            unsigned long offset1;
            if (flags & MAP_ANON)
                offset1 = 0;
            else
                offset1 = offset + real_start - start;
            p = mmap(g2h(real_start), real_end - real_start,
                     prot, flags, fd, offset1);
            if (p == MAP_FAILED)
                goto fail;
        }
    }
 the_end1:
    page_set_flags(start, start + len, prot | PAGE_VALID);
 the_end:
#ifdef DEBUG_MMAP
    printf("ret=0x" TARGET_FMT_lx "\n", start);
    page_dump(stdout);
    printf("\n");
#endif
    mmap_unlock();
    return start;
fail:
    mmap_unlock();
    return -1;
}

int target_munmap(abi_ulong start, abi_ulong len)
{
    abi_ulong end, real_start, real_end, addr;
    int prot, ret;

#ifdef DEBUG_MMAP
    printf("munmap: start=0x%lx len=0x%lx\n", start, len);
#endif
    if (start & ~TARGET_PAGE_MASK)
        return -EINVAL;
    len = TARGET_PAGE_ALIGN(len);
    if (len == 0)
        return -EINVAL;
    mmap_lock();
    end = start + len;
    real_start = start & qemu_host_page_mask;
    real_end = HOST_PAGE_ALIGN(end);

    if (start > real_start) {
        /* handle host page containing start */
        prot = 0;
        for(addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) {
            prot |= page_get_flags(addr);
        }
        if (real_end == real_start + qemu_host_page_size) {
            for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
                prot |= page_get_flags(addr);
            }
            end = real_end;
        }
        if (prot != 0)
            real_start += qemu_host_page_size;
    }
    if (end < real_end) {
        prot = 0;
        for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
            prot |= page_get_flags(addr);
        }
        if (prot != 0)
            real_end -= qemu_host_page_size;
    }

    ret = 0;
    /* unmap what we can */
    if (real_start < real_end) {
        ret = munmap(g2h(real_start), real_end - real_start);
    }

    if (ret == 0)
        page_set_flags(start, start + len, 0);
    mmap_unlock();
    return ret;
}

int target_msync(abi_ulong start, abi_ulong len, int flags)
{
    abi_ulong end;

    if (start & ~TARGET_PAGE_MASK)
        return -EINVAL;
    len = TARGET_PAGE_ALIGN(len);
    end = start + len;
    if (end < start)
        return -EINVAL;
    if (end == start)
        return 0;

    start &= qemu_host_page_mask;
    return msync(g2h(start), end - start, flags);
}
Commit	Line	Data
84778508 BS	1	/*
	2	* mmap support for qemu
	3	*
	4	* Copyright (c) 2003 - 2008 Fabrice Bellard
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
8167ee88	17	* along with this program; if not, see <http://www.gnu.org/licenses/>.
84778508	18	*/
2231197c	19	#include "qemu/osdep.h"
84778508 BS	20	#include <sys/mman.h>
	21
	22	#include "qemu.h"
	23	#include "qemu-common.h"
6c173b3c	24	#include "bsd-mman.h"
84778508 BS	25
	26	//#define DEBUG_MMAP
	27
2f7bb878	28	#if defined(CONFIG_USE_NPTL)
84778508 BS	29	pthread_mutex_t mmap_mutex;
	30	static int __thread mmap_lock_count;
	31
	32	void mmap_lock(void)
	33	{
	34	if (mmap_lock_count++ == 0) {
	35	pthread_mutex_lock(&mmap_mutex);
	36	}
	37	}
	38
	39	void mmap_unlock(void)
	40	{
	41	if (--mmap_lock_count == 0) {
	42	pthread_mutex_unlock(&mmap_mutex);
	43	}
	44	}
	45
	46	/* Grab lock to make sure things are in a consistent state after fork(). */
	47	void mmap_fork_start(void)
	48	{
	49	if (mmap_lock_count)
	50	abort();
	51	pthread_mutex_lock(&mmap_mutex);
	52	}
	53
	54	void mmap_fork_end(int child)
	55	{
	56	if (child)
	57	pthread_mutex_init(&mmap_mutex, NULL);
	58	else
	59	pthread_mutex_unlock(&mmap_mutex);
	60	}
	61	#else
	62	/* We aren't threadsafe to start with, so no need to worry about locking. */
	63	void mmap_lock(void)
	64	{
	65	}
	66
	67	void mmap_unlock(void)
	68	{
	69	}
	70	#endif
	71
84778508 BS	72	/* NOTE: all the constants are the HOST ones, but addresses are target. */
	73	int target_mprotect(abi_ulong start, abi_ulong len, int prot)
	74	{
	75	abi_ulong end, host_start, host_end, addr;
	76	int prot1, ret;
	77
	78	#ifdef DEBUG_MMAP
	79	printf("mprotect: start=0x" TARGET_FMT_lx
	80	" len=0x" TARGET_FMT_lx " prot=%c%c%c\n", start, len,
	81	prot & PROT_READ ? 'r' : '-',
	82	prot & PROT_WRITE ? 'w' : '-',
	83	prot & PROT_EXEC ? 'x' : '-');
	84	#endif
	85
	86	if ((start & ~TARGET_PAGE_MASK) != 0)
	87	return -EINVAL;
	88	len = TARGET_PAGE_ALIGN(len);
	89	end = start + len;
	90	if (end < start)
	91	return -EINVAL;
	92	prot &= PROT_READ \| PROT_WRITE \| PROT_EXEC;
	93	if (len == 0)
	94	return 0;
	95
	96	mmap_lock();
	97	host_start = start & qemu_host_page_mask;
	98	host_end = HOST_PAGE_ALIGN(end);
	99	if (start > host_start) {
	100	/* handle host page containing start */
	101	prot1 = prot;
	102	for(addr = host_start; addr < start; addr += TARGET_PAGE_SIZE) {
	103	prot1 \|= page_get_flags(addr);
	104	}
	105	if (host_end == host_start + qemu_host_page_size) {
	106	for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
	107	prot1 \|= page_get_flags(addr);
	108	}
	109	end = host_end;
	110	}
	111	ret = mprotect(g2h(host_start), qemu_host_page_size, prot1 & PAGE_BITS);
	112	if (ret != 0)
	113	goto error;
	114	host_start += qemu_host_page_size;
	115	}
	116	if (end < host_end) {
	117	prot1 = prot;
	118	for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
	119	prot1 \|= page_get_flags(addr);
	120	}
	121	ret = mprotect(g2h(host_end - qemu_host_page_size), qemu_host_page_size,
	122	prot1 & PAGE_BITS);
	123	if (ret != 0)
	124	goto error;
	125	host_end -= qemu_host_page_size;
	126	}
	127
	128	/* handle the pages in the middle */
	129	if (host_start < host_end) {
	130	ret = mprotect(g2h(host_start), host_end - host_start, prot);
	131	if (ret != 0)
	132	goto error;
	133	}
	134	page_set_flags(start, start + len, prot \| PAGE_VALID);
	135	mmap_unlock();
136	return 0;
137	error:
138	mmap_unlock();
139	return ret;
140	}
141
142	/* map an incomplete host page */
143	static int mmap_frag(abi_ulong real_start,
144	abi_ulong start, abi_ulong end,
145	int prot, int flags, int fd, abi_ulong offset)
146	{
147	abi_ulong real_end, addr;
148	void *host_start;
149	int prot1, prot_new;
150
151	real_end = real_start + qemu_host_page_size;
152	host_start = g2h(real_start);
153
154	/* get the protection of the target pages outside the mapping */
155	prot1 = 0;
156	for(addr = real_start; addr < real_end; addr++) {
157	if (addr < start \|\| addr >= end)
158	prot1 \|= page_get_flags(addr);
159	}
160
161	if (prot1 == 0) {
162	/* no page was there, so we allocate one */
163	void *p = mmap(host_start, qemu_host_page_size, prot,
164	flags \| MAP_ANON, -1, 0);
165	if (p == MAP_FAILED)
166	return -1;
167	prot1 = prot;
168	}
169	prot1 &= PAGE_BITS;
170
171	prot_new = prot \| prot1;
172	if (!(flags & MAP_ANON)) {
173	/* msync() won't work here, so we return an error if write is
174	possible while it is a shared mapping */
6c173b3c	175	if ((flags & TARGET_BSD_MAP_FLAGMASK) == MAP_SHARED &&
84778508	176	(prot & PROT_WRITE))
059bca46	177	return -1;
84778508 BS	178
	179	/* adjust protection to be able to read */
	180	if (!(prot1 & PROT_WRITE))
	181	mprotect(host_start, qemu_host_page_size, prot1 \| PROT_WRITE);
	182
	183	/* read the corresponding file data */
	184	pread(fd, g2h(start), end - start, offset);
	185
	186	/* put final protection */
	187	if (prot_new != (prot1 \| PROT_WRITE))
	188	mprotect(host_start, qemu_host_page_size, prot_new);
	189	} else {
	190	/* just update the protection */
	191	if (prot_new != prot1) {
	192	mprotect(host_start, qemu_host_page_size, prot_new);
	193	}
	194	}
	195	return 0;
	196	}
	197
	198	#if defined(__CYGWIN__)
	199	/* Cygwin doesn't have a whole lot of address space. */
	200	static abi_ulong mmap_next_start = 0x18000000;
	201	#else
	202	static abi_ulong mmap_next_start = 0x40000000;
	203	#endif
	204
	205	unsigned long last_brk;
	206
	207	/* find a free memory area of size 'size'. The search starts at
	208	'start'. If 'start' == 0, then a default start address is used.
	209	Return -1 if error.
	210	*/
	211	/* page_init() marks pages used by the host as reserved to be sure not
	212	to use them. */
	213	static abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size)
	214	{
	215	abi_ulong addr, addr1, addr_start;
	216	int prot;
	217	unsigned long new_brk;
	218
	219	new_brk = (unsigned long)sbrk(0);
	220	if (last_brk && last_brk < new_brk && last_brk == (target_ulong)last_brk) {
	221	/* This is a hack to catch the host allocating memory with brk().
	222	If it uses mmap then we loose.
	223	FIXME: We really want to avoid the host allocating memory in
	224	the first place, and maybe leave some slack to avoid switching
	225	to mmap. */
	226	page_set_flags(last_brk & TARGET_PAGE_MASK,
	227	TARGET_PAGE_ALIGN(new_brk),
	228	PAGE_RESERVED);
	229	}
	230	last_brk = new_brk;
	231
	232	size = HOST_PAGE_ALIGN(size);
	233	start = start & qemu_host_page_mask;
	234	addr = start;
	235	if (addr == 0)
	236	addr = mmap_next_start;
	237	addr_start = addr;
	238	for(;;) {
	239	prot = 0;
	240	for(addr1 = addr; addr1 < (addr + size); addr1 += TARGET_PAGE_SIZE) {
	241	prot \|= page_get_flags(addr1);
242	}
243	if (prot == 0)
244	break;
245	addr += qemu_host_page_size;
246	/* we found nothing */
247	if (addr == addr_start)
248	return (abi_ulong)-1;
249	}
250	if (start == 0)
251	mmap_next_start = addr + size;
252	return addr;
253	}
254
255	/* NOTE: all the constants are the HOST ones */
256	abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
257	int flags, int fd, abi_ulong offset)
258	{
259	abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len;
260	unsigned long host_start;
261
262	mmap_lock();
263	#ifdef DEBUG_MMAP
264	{
265	printf("mmap: start=0x" TARGET_FMT_lx
266	" len=0x" TARGET_FMT_lx " prot=%c%c%c flags=",
267	start, len,
268	prot & PROT_READ ? 'r' : '-',
269	prot & PROT_WRITE ? 'w' : '-',
270	prot & PROT_EXEC ? 'x' : '-');
271	if (flags & MAP_FIXED)
272	printf("MAP_FIXED ");
273	if (flags & MAP_ANON)
274	printf("MAP_ANON ");
6c173b3c	275	switch(flags & TARGET_BSD_MAP_FLAGMASK) {
84778508 BS	276	case MAP_PRIVATE:
	277	printf("MAP_PRIVATE ");
	278	break;
	279	case MAP_SHARED:
	280	printf("MAP_SHARED ");
	281	break;
	282	default:
6c173b3c	283	printf("[MAP_FLAGMASK=0x%x] ", flags & TARGET_BSD_MAP_FLAGMASK);
84778508 BS	284	break;
	285	}
	286	printf("fd=%d offset=" TARGET_FMT_lx "\n", fd, offset);
	287	}
	288	#endif
	289
	290	if (offset & ~TARGET_PAGE_MASK) {
	291	errno = EINVAL;
	292	goto fail;
	293	}
	294
	295	len = TARGET_PAGE_ALIGN(len);
	296	if (len == 0)
	297	goto the_end;
	298	real_start = start & qemu_host_page_mask;
	299
	300	if (!(flags & MAP_FIXED)) {
	301	abi_ulong mmap_start;
	302	void *p;
	303	host_offset = offset & qemu_host_page_mask;
	304	host_len = len + offset - host_offset;
	305	host_len = HOST_PAGE_ALIGN(host_len);
	306	mmap_start = mmap_find_vma(real_start, host_len);
	307	if (mmap_start == (abi_ulong)-1) {
	308	errno = ENOMEM;
	309	goto fail;
	310	}
	311	/* Note: we prefer to control the mapping address. It is
	312	especially important if qemu_host_page_size >
	313	qemu_real_host_page_size */
	314	p = mmap(g2h(mmap_start),
	315	host_len, prot, flags \| MAP_FIXED, fd, host_offset);
	316	if (p == MAP_FAILED)
	317	goto fail;
	318	/* update start so that it points to the file position at 'offset' */
	319	host_start = (unsigned long)p;
	320	if (!(flags & MAP_ANON))
	321	host_start += offset - host_offset;
	322	start = h2g(host_start);
	323	} else {
	324	int flg;
	325	target_ulong addr;
	326
	327	if (start & ~TARGET_PAGE_MASK) {
	328	errno = EINVAL;
	329	goto fail;
	330	}
	331	end = start + len;
	332	real_end = HOST_PAGE_ALIGN(end);
	333
	334	for(addr = real_start; addr < real_end; addr += TARGET_PAGE_SIZE) {
	335	flg = page_get_flags(addr);
	336	if (flg & PAGE_RESERVED) {
	337	errno = ENXIO;
	338	goto fail;
	339	}
	340	}
	341
	342	/* worst case: we cannot map the file because the offset is not
	343	aligned, so we read it */
	344	if (!(flags & MAP_ANON) &&
	345	(offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) {
	346	/* msync() won't work here, so we return an error if write is
	347	possible while it is a shared mapping */
6c173b3c	348	if ((flags & TARGET_BSD_MAP_FLAGMASK) == MAP_SHARED &&
84778508 BS	349	(prot & PROT_WRITE)) {
	350	errno = EINVAL;
	351	goto fail;
	352	}
	353	retaddr = target_mmap(start, len, prot \| PROT_WRITE,
	354	MAP_FIXED \| MAP_PRIVATE \| MAP_ANON,
	355	-1, 0);
	356	if (retaddr == -1)
	357	goto fail;
	358	pread(fd, g2h(start), len, offset);
	359	if (!(prot & PROT_WRITE)) {
	360	ret = target_mprotect(start, len, prot);
	361	if (ret != 0) {
	362	start = ret;
	363	goto the_end;
	364	}
	365	}
	366	goto the_end;
	367	}
	368
	369	/* handle the start of the mapping */
	370	if (start > real_start) {
	371	if (real_end == real_start + qemu_host_page_size) {
	372	/* one single host page */
	373	ret = mmap_frag(real_start, start, end,
	374	prot, flags, fd, offset);
	375	if (ret == -1)
	376	goto fail;
	377	goto the_end1;
	378	}
	379	ret = mmap_frag(real_start, start, real_start + qemu_host_page_size,
	380	prot, flags, fd, offset);
	381	if (ret == -1)
	382	goto fail;
	383	real_start += qemu_host_page_size;
	384	}
	385	/* handle the end of the mapping */
	386	if (end < real_end) {
	387	ret = mmap_frag(real_end - qemu_host_page_size,
	388	real_end - qemu_host_page_size, real_end,
	389	prot, flags, fd,
	390	offset + real_end - qemu_host_page_size - start);
	391	if (ret == -1)
	392	goto fail;
	393	real_end -= qemu_host_page_size;
	394	}
	395
	396	/* map the middle (easier) */
	397	if (real_start < real_end) {
	398	void *p;
	399	unsigned long offset1;
	400	if (flags & MAP_ANON)
	401	offset1 = 0;
	402	else
	403	offset1 = offset + real_start - start;
	404	p = mmap(g2h(real_start), real_end - real_start,
	405	prot, flags, fd, offset1);
	406	if (p == MAP_FAILED)
	407	goto fail;
	408	}
	409	}
	410	the_end1:
	411	page_set_flags(start, start + len, prot \| PAGE_VALID);
	412	the_end:
413	#ifdef DEBUG_MMAP
414	printf("ret=0x" TARGET_FMT_lx "\n", start);
415	page_dump(stdout);
416	printf("\n");
417	#endif
418	mmap_unlock();
419	return start;
420	fail:
421	mmap_unlock();
422	return -1;
423	}
424
425	int target_munmap(abi_ulong start, abi_ulong len)
426	{
427	abi_ulong end, real_start, real_end, addr;
428	int prot, ret;
429
430	#ifdef DEBUG_MMAP
431	printf("munmap: start=0x%lx len=0x%lx\n", start, len);
432	#endif
433	if (start & ~TARGET_PAGE_MASK)
434	return -EINVAL;
435	len = TARGET_PAGE_ALIGN(len);
436	if (len == 0)
437	return -EINVAL;
438	mmap_lock();
439	end = start + len;
440	real_start = start & qemu_host_page_mask;
441	real_end = HOST_PAGE_ALIGN(end);
442
443	if (start > real_start) {
444	/* handle host page containing start */
445	prot = 0;
446	for(addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) {
447	prot \|= page_get_flags(addr);
448	}
449	if (real_end == real_start + qemu_host_page_size) {
450	for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
451	prot \|= page_get_flags(addr);
452	}
453	end = real_end;
454	}
455	if (prot != 0)
456	real_start += qemu_host_page_size;
457	}
458	if (end < real_end) {
459	prot = 0;
460	for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
461	prot \|= page_get_flags(addr);
462	}
463	if (prot != 0)
464	real_end -= qemu_host_page_size;
465	}
466
467	ret = 0;
468	/* unmap what we can */
469	if (real_start < real_end) {
470	ret = munmap(g2h(real_start), real_end - real_start);
471	}
472
473	if (ret == 0)
474	page_set_flags(start, start + len, 0);
475	mmap_unlock();
476	return ret;
477	}
478
479	int target_msync(abi_ulong start, abi_ulong len, int flags)
480	{
481	abi_ulong end;
482
483	if (start & ~TARGET_PAGE_MASK)
484	return -EINVAL;
485	len = TARGET_PAGE_ALIGN(len);
486	end = start + len;
487	if (end < start)
488	return -EINVAL;
489	if (end == start)
490	return 0;
491
492	start &= qemu_host_page_mask;
493	return msync(g2h(start), end - start, flags);
494	}