Add mmap ioctl to mmfs.

main
Eric Anholt 2008-04-23 14:52:30 -07:00
parent 8c741ed54e
commit 22877864c2
4 changed files with 175 additions and 1 deletions

1
.gitignore vendored
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@ -59,6 +59,7 @@ tests/getstats
tests/getversion tests/getversion
tests/lock tests/lock
tests/mmfs_basic tests/mmfs_basic
tests/mmfs_mmap
tests/mmfs_readwrite tests/mmfs_readwrite
tests/openclose tests/openclose
tests/setversion tests/setversion

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@ -32,6 +32,8 @@
#include <linux/fs.h> #include <linux/fs.h>
#include <linux/file.h> #include <linux/file.h>
#include <linux/module.h> #include <linux/module.h>
#include <linux/mman.h>
#include <linux/pagemap.h>
#include "mmfs.h" #include "mmfs.h"
/** @file mmfs.c /** @file mmfs.c
@ -244,6 +246,45 @@ mmfs_pread_ioctl(struct inode *inode, struct file *filp,
return 0; return 0;
} }
/**
* Maps the contents of an object, returning the address it is mapped
* into.
*
* While the mapping holds a reference on the contents of the object, it doesn't
* imply a ref on the object itself.
*/
static int
mmfs_mmap_ioctl(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
struct mmfs_file *mmfs_filp = filp->private_data;
struct mmfs_mmap_args args;
struct mmfs_object *obj;
loff_t offset;
if (copy_from_user(&args, (void __user *)arg, sizeof(args)))
return -EFAULT;
obj = mmfs_object_lookup(mmfs_filp, args.handle);
if (obj == NULL)
return -EINVAL;
offset = args.offset;
down_write(&current->mm->mmap_sem);
args.addr = (void *)do_mmap(obj->filp, 0, args.size,
PROT_READ | PROT_WRITE, MAP_SHARED,
args.offset);
up_write(&current->mm->mmap_sem);
mmfs_object_unreference(obj);
if (copy_to_user((void __user *)arg, &args, sizeof(args)))
return -EFAULT;
return 0;
}
/** /**
* Writes data to the object referenced by handle. * Writes data to the object referenced by handle.
* *
@ -297,6 +338,8 @@ mmfs_ioctl(struct inode *inode, struct file *filp,
return mmfs_pread_ioctl(inode, filp, cmd, arg); return mmfs_pread_ioctl(inode, filp, cmd, arg);
case MMFS_IOCTL_PWRITE: case MMFS_IOCTL_PWRITE:
return mmfs_pwrite_ioctl(inode, filp, cmd, arg); return mmfs_pwrite_ioctl(inode, filp, cmd, arg);
case MMFS_IOCTL_MMAP:
return mmfs_mmap_ioctl(inode, filp, cmd, arg);
default: default:
return -EINVAL; return -EINVAL;
} }

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@ -24,7 +24,8 @@ TESTS = auth \
setversion \ setversion \
updatedraw \ updatedraw \
mmfs_basic \ mmfs_basic \
mmfs_readwrite mmfs_readwrite \
mmfs_mmap
EXTRA_PROGRAMS = $(TESTS) EXTRA_PROGRAMS = $(TESTS)
CLEANFILES = $(EXTRA_PROGRAMS) $(EXTRA_LTLIBRARIES) CLEANFILES = $(EXTRA_PROGRAMS) $(EXTRA_LTLIBRARIES)

129
tests/mmfs_mmap.c Normal file
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@ -0,0 +1,129 @@
/*
* Copyright © 2008 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
* Authors:
* Eric Anholt <eric@anholt.net>
*
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <fcntl.h>
#include <inttypes.h>
#include <errno.h>
#include <sys/stat.h>
#include "mmfs.h"
#define MMFS_BUFFER_SIZE 16384
int do_read(int fd, int handle, void *buf, int offset, int size)
{
struct mmfs_pread_args read;
/* Ensure that we don't have any convenient data in buf in case
* we fail.
*/
memset(buf, 0xd0, size);
memset(&read, 0, sizeof(read));
read.handle = handle;
read.data = buf;
read.size = size;
read.offset = offset;
return ioctl(fd, MMFS_IOCTL_PREAD, &read);
}
int do_write(int fd, int handle, void *buf, int offset, int size)
{
struct mmfs_pwrite_args write;
memset(&write, 0, sizeof(write));
write.handle = handle;
write.data = buf;
write.size = size;
write.offset = offset;
return ioctl(fd, MMFS_IOCTL_PWRITE, &write);
}
int main(int argc, char **argv)
{
int fd;
struct mmfs_alloc_args alloc;
struct mmfs_mmap_args mmap;
struct mmfs_unreference_args unref;
uint8_t expected[MMFS_BUFFER_SIZE];
uint8_t buf[MMFS_BUFFER_SIZE];
int ret;
int handle;
fd = open_mmfs_device();
memset(&mmap, 0, sizeof(mmap));
mmap.handle = 0x10101010;
mmap.offset = 0;
mmap.size = 4096;
printf("Testing mmaping of bad object.\n");
ret = ioctl(fd, MMFS_IOCTL_MMAP, &mmap);
assert(ret == -1 && errno == EINVAL);
memset(&alloc, 0, sizeof(alloc));
alloc.size = MMFS_BUFFER_SIZE;
ret = ioctl(fd, MMFS_IOCTL_ALLOC, &alloc);
assert(ret == 0);
handle = alloc.handle;
printf("Testing mmaping of newly allocated object.\n");
mmap.handle = handle;
mmap.offset = 0;
mmap.size = MMFS_BUFFER_SIZE;
ret = ioctl(fd, MMFS_IOCTL_MMAP, &mmap);
assert(ret == 0);
printf("Testing contents of newly allocated object.\n");
memset(expected, 0, sizeof(expected));
assert(memcmp(mmap.addr, expected, sizeof(expected)) == 0);
printf("Testing coherency of writes and mmap reads.\n");
memset(buf, 0, sizeof(buf));
memset(buf + 1024, 0x01, 1024);
memset(expected + 1024, 0x01, 1024);
ret = do_write(fd, handle, buf, 0, MMFS_BUFFER_SIZE);
assert(ret == 0);
assert(memcmp(buf, mmap.addr, sizeof(buf)) == 0);
printf("Testing that mapping stays after unreference\n");
unref.handle = handle;
ret = ioctl(fd, MMFS_IOCTL_UNREFERENCE, &unref);
assert(ret == 0);
assert(memcmp(buf, mmap.addr, sizeof(buf)) == 0);
printf("Testing unmapping\n");
munmap(mmap.addr, MMFS_BUFFER_SIZE);
close(fd);
return 0;
}