#include <linux/fs.h>
#include <linux/file.h>
#include <linux/module.h>
+#include <linux/mman.h>
+#include <linux/pagemap.h>
#include "mmfs.h"
/** @file mmfs.c
}
/**
+ * 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(¤t->mm->mmap_sem);
+ args.addr = (void *)do_mmap(obj->filp, 0, args.size,
+ PROT_READ | PROT_WRITE, MAP_SHARED,
+ args.offset);
+ up_write(¤t->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.
*
* On error, the contents of the buffer that were to be modified are undefined.
return mmfs_pread_ioctl(inode, filp, cmd, arg);
case MMFS_IOCTL_PWRITE:
return mmfs_pwrite_ioctl(inode, filp, cmd, arg);
+ case MMFS_IOCTL_MMAP:
+ return mmfs_mmap_ioctl(inode, filp, cmd, arg);
default:
return -EINVAL;
}
--- /dev/null
+/*
+ * 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;
+}
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