-/*
+/*
* Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
int error;
};
-extern int open_ubd_file(char *file, struct openflags *openflags,
+extern int open_ubd_file(char *file, struct openflags *openflags, int shared,
char **backing_file_out, int *bitmap_offset_out,
unsigned long *bitmap_len_out, int *data_offset_out,
int *create_cow_out);
static int ubd_release(struct inode * inode, struct file * file);
static int ubd_ioctl(struct inode * inode, struct file * file,
unsigned int cmd, unsigned long arg);
+static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo);
#define MAX_DEV (8)
.open = ubd_open,
.release = ubd_release,
.ioctl = ubd_ioctl,
+ .getgeo = ubd_getgeo,
};
/* Protected by the queue_lock */
static struct gendisk *ubd_gendisk[MAX_DEV];
static struct gendisk *fake_gendisk[MAX_DEV];
-
+
#ifdef CONFIG_BLK_DEV_UBD_SYNC
#define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \
.cl = 1 })
__u64 size;
struct openflags boot_openflags;
struct openflags openflags;
+ int shared;
int no_cow;
struct cow cow;
struct platform_device pdev;
.boot_openflags = OPEN_FLAGS, \
.openflags = OPEN_FLAGS, \
.no_cow = 0, \
+ .shared = 0, \
.cow = DEFAULT_COW, \
}
}
major = simple_strtoul(str, &end, 0);
if((*end != '\0') || (end == str)){
- printk(KERN_ERR
+ printk(KERN_ERR
"ubd_setup : didn't parse major number\n");
return(1);
}
printk(KERN_ERR "Can't assign a fake major twice\n");
goto out1;
}
-
+
fake_major = major;
printk(KERN_INFO "Setting extra ubd major number to %d\n",
if (index_out)
*index_out = n;
- for (i = 0; i < 4; i++) {
+ for (i = 0; i < sizeof("rscd="); i++) {
switch (*str) {
case 'r':
flags.w = 0;
case 'd':
dev->no_cow = 1;
break;
+ case 'c':
+ dev->shared = 1;
+ break;
case '=':
str++;
goto break_loop;
default:
- printk(KERN_ERR "ubd_setup : Expected '=' or flag letter (r,s or d)\n");
+ printk(KERN_ERR "ubd_setup : Expected '=' or flag letter (r, s, c, or d)\n");
goto out;
}
str++;
spin_unlock(&ubd_io_lock);
return;
}
-
+
ubd_finish(rq, req.error);
reactivate_fd(thread_fd, UBD_IRQ);
do_ubd_request(ubd_queue);
void kill_io_thread(void)
{
- if(io_pid != -1)
+ if(io_pid != -1)
os_kill_process(io_pid, 1);
}
create_cow = 0;
create_ptr = (dev->cow.file != NULL) ? &create_cow : NULL;
back_ptr = dev->no_cow ? NULL : &dev->cow.file;
- dev->fd = open_ubd_file(dev->file, &dev->openflags, back_ptr,
- &dev->cow.bitmap_offset, &dev->cow.bitmap_len,
- &dev->cow.data_offset, create_ptr);
+ dev->fd = open_ubd_file(dev->file, &dev->openflags, dev->shared,
+ back_ptr, &dev->cow.bitmap_offset,
+ &dev->cow.bitmap_len, &dev->cow.data_offset,
+ create_ptr);
if((dev->fd == -ENOENT) && create_cow){
- dev->fd = create_cow_file(dev->file, dev->cow.file,
+ dev->fd = create_cow_file(dev->file, dev->cow.file,
dev->openflags, 1 << 9, PAGE_SIZE,
- &dev->cow.bitmap_offset,
+ &dev->cow.bitmap_offset,
&dev->cow.bitmap_len,
&dev->cow.data_offset);
if(dev->fd >= 0){
}
flush_tlb_kernel_vm();
- err = read_cow_bitmap(dev->fd, dev->cow.bitmap,
- dev->cow.bitmap_offset,
+ err = read_cow_bitmap(dev->fd, dev->cow.bitmap,
+ dev->cow.bitmap_offset,
dev->cow.bitmap_len);
if(err < 0)
goto error;
flags = dev->openflags;
flags.w = 0;
- err = open_ubd_file(dev->cow.file, &flags, NULL, NULL, NULL,
- NULL, NULL);
+ err = open_ubd_file(dev->cow.file, &flags, dev->shared, NULL,
+ NULL, NULL, NULL, NULL);
if(err < 0) goto error;
dev->cow.fd = err;
}
dev->size = ROUND_BLOCK(dev->size);
err = ubd_new_disk(MAJOR_NR, dev->size, n, &ubd_gendisk[n]);
- if(err)
+ if(err)
goto out_close;
-
+
if(fake_major != MAJOR_NR)
- ubd_new_disk(fake_major, dev->size, n,
+ ubd_new_disk(fake_major, dev->size, n,
&fake_gendisk[n]);
/* perhaps this should also be under the "if (fake_major)" above */
return -1;
}
platform_driver_register(&ubd_driver);
- for (i = 0; i < MAX_DEV; i++)
+ for (i = 0; i < MAX_DEV; i++)
ubd_add(i);
return 0;
}
* enough. So use anyway the io thread. */
}
stack = alloc_stack(0, 0);
- io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *),
+ io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *),
&thread_fd);
if(io_pid < 0){
- printk(KERN_ERR
+ printk(KERN_ERR
"ubd : Failed to start I/O thread (errno = %d) - "
"falling back to synchronous I/O\n", -io_pid);
io_pid = -1;
return(0);
}
- err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr,
+ err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr,
SA_INTERRUPT, "ubd", ubd_dev);
if(err != 0)
printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err);
- return(err);
+ return 0;
}
device_initcall(ubd_driver_init);
if(req->op == UBD_READ) {
for(i = 0; i < req->length >> 9; i++){
if(ubd_test_bit(sector + i, (unsigned char *) bitmap))
- ubd_set_bit(i, (unsigned char *)
+ ubd_set_bit(i, (unsigned char *)
&req->sector_mask);
}
}
/* This should be impossible now */
if((rq_data_dir(req) == WRITE) && !dev->openflags.w){
- printk("Write attempted on readonly ubd device %s\n",
+ printk("Write attempted on readonly ubd device %s\n",
disk->disk_name);
end_request(req, 0);
return(1);
}
}
+static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
+{
+ struct ubd *dev = bdev->bd_disk->private_data;
+
+ geo->heads = 128;
+ geo->sectors = 32;
+ geo->cylinders = dev->size / (128 * 32 * 512);
+ return 0;
+}
+
static int ubd_ioctl(struct inode * inode, struct file * file,
unsigned int cmd, unsigned long arg)
{
- struct hd_geometry __user *loc = (struct hd_geometry __user *) arg;
struct ubd *dev = inode->i_bdev->bd_disk->private_data;
struct hd_driveid ubd_id = {
.cyls = 0,
};
switch (cmd) {
- struct hd_geometry g;
struct cdrom_volctrl volume;
- case HDIO_GETGEO:
- if(!loc) return(-EINVAL);
- g.heads = 128;
- g.sectors = 32;
- g.cylinders = dev->size / (128 * 32 * 512);
- g.start = get_start_sect(inode->i_bdev);
- return(copy_to_user(loc, &g, sizeof(g)) ? -EFAULT : 0);
-
case HDIO_GET_IDENTITY:
ubd_id.cyls = dev->size / (128 * 32 * 512);
if(copy_to_user((char __user *) arg, (char *) &ubd_id,
return(-EINVAL);
}
-static int same_backing_files(char *from_cmdline, char *from_cow, char *cow)
+static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow)
{
struct uml_stat buf1, buf2;
int err;
- if(from_cmdline == NULL) return(1);
- if(!strcmp(from_cmdline, from_cow)) return(1);
+ if(from_cmdline == NULL)
+ return 0;
+ if(!strcmp(from_cmdline, from_cow))
+ return 0;
err = os_stat_file(from_cmdline, &buf1);
if(err < 0){
printk("Couldn't stat '%s', err = %d\n", from_cmdline, -err);
- return(1);
+ return 0;
}
err = os_stat_file(from_cow, &buf2);
if(err < 0){
printk("Couldn't stat '%s', err = %d\n", from_cow, -err);
- return(1);
+ return 1;
}
if((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino))
- return(1);
+ return 0;
printk("Backing file mismatch - \"%s\" requested,\n"
"\"%s\" specified in COW header of \"%s\"\n",
from_cmdline, from_cow, cow);
- return(0);
+ return 1;
}
static int backing_file_mismatch(char *file, __u64 size, time_t mtime)
{
unsigned long modtime;
- long long actual;
+ unsigned long long actual;
int err;
err = os_file_modtime(file, &modtime);
return(0);
}
-int open_ubd_file(char *file, struct openflags *openflags,
+int open_ubd_file(char *file, struct openflags *openflags, int shared,
char **backing_file_out, int *bitmap_offset_out,
unsigned long *bitmap_len_out, int *data_offset_out,
int *create_cow_out)
unsigned long long size;
__u32 version, align;
char *backing_file;
- int fd, err, sectorsize, same, mode = 0644;
+ int fd, err, sectorsize, asked_switch, mode = 0644;
fd = os_open_file(file, *openflags, mode);
- if(fd < 0){
- if((fd == -ENOENT) && (create_cow_out != NULL))
+ if (fd < 0) {
+ if ((fd == -ENOENT) && (create_cow_out != NULL))
*create_cow_out = 1;
- if(!openflags->w ||
- ((fd != -EROFS) && (fd != -EACCES))) return(fd);
+ if (!openflags->w ||
+ ((fd != -EROFS) && (fd != -EACCES)))
+ return fd;
openflags->w = 0;
fd = os_open_file(file, *openflags, mode);
- if(fd < 0)
- return(fd);
+ if (fd < 0)
+ return fd;
}
- err = os_lock_file(fd, openflags->w);
- if(err < 0){
- printk("Failed to lock '%s', err = %d\n", file, -err);
- goto out_close;
+ if(shared)
+ printk("Not locking \"%s\" on the host\n", file);
+ else {
+ err = os_lock_file(fd, openflags->w);
+ if(err < 0){
+ printk("Failed to lock '%s', err = %d\n", file, -err);
+ goto out_close;
+ }
}
- if(backing_file_out == NULL) return(fd);
+ /* Successful return case! */
+ if(backing_file_out == NULL)
+ return(fd);
err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime,
&size, §orsize, &align, bitmap_offset_out);
"errno = %d\n", file, -err);
goto out_close;
}
- if(err) return(fd);
-
- if(backing_file_out == NULL) return(fd);
+ if(err)
+ return(fd);
- same = same_backing_files(*backing_file_out, backing_file, file);
+ asked_switch = path_requires_switch(*backing_file_out, backing_file, file);
- if(!same && !backing_file_mismatch(*backing_file_out, size, mtime)){
+ /* Allow switching only if no mismatch. */
+ if (asked_switch && !backing_file_mismatch(*backing_file_out, size, mtime)) {
printk("Switching backing file to '%s'\n", *backing_file_out);
err = write_cow_header(file, fd, *backing_file_out,
sectorsize, align, &size);
- if(err){
+ if (err) {
printk("Switch failed, errno = %d\n", -err);
- return(err);
+ goto out_close;
}
- }
- else {
+ } else {
*backing_file_out = backing_file;
err = backing_file_mismatch(*backing_file_out, size, mtime);
- if(err) goto out_close;
+ if (err)
+ goto out_close;
}
cow_sizes(version, size, sectorsize, align, *bitmap_offset_out,
bitmap_len_out, data_offset_out);
- return(fd);
+ return fd;
out_close:
os_close_file(fd);
- return(err);
+ return err;
}
int create_cow_file(char *cow_file, char *backing_file, struct openflags flags,
int err, fd;
flags.c = 1;
- fd = open_ubd_file(cow_file, &flags, NULL, NULL, NULL, NULL, NULL);
+ fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL);
if(fd < 0){
err = fd;
printk("Open of COW file '%s' failed, errno = %d\n", cow_file,