#define DRIVER_NAME "uml-blkdev"
+/* Can be taken in interrupt context, and is passed to the block layer to lock
+ * the request queue. Kernel side code knows that. */
static DEFINE_SPINLOCK(ubd_io_lock);
-static DEFINE_SPINLOCK(ubd_lock);
-static void (*do_ubd)(void);
+static DEFINE_MUTEX(ubd_lock);
+
+/* XXX - this made sense in 2.4 days, now it's only used as a boolean, and
+ * probably it doesn't make sense even for that. */
+static int do_ubd;
static int ubd_open(struct inode * inode, struct file * filp);
static int ubd_release(struct inode * inode, struct file * file);
__u64 size;
struct openflags boot_openflags;
struct openflags openflags;
- int shared;
- int no_cow;
+ unsigned shared:1;
+ unsigned no_cow:1;
struct cow cow;
struct platform_device pdev;
};
struct ubd ubd_devs[MAX_DEV] = { [ 0 ... MAX_DEV - 1 ] = DEFAULT_UBD };
-static int ubd0_init(void)
-{
- struct ubd *ubd_dev = &ubd_devs[0];
-
- if(ubd_dev->file == NULL)
- ubd_dev->file = "root_fs";
- return(0);
-}
-
-__initcall(ubd0_init);
-
/* Only changed by fake_ide_setup which is a setup */
static int fake_ide = 0;
static struct proc_dir_entry *proc_ide_root = NULL;
return(n);
}
+/* If *index_out == -1 at exit, the passed option was a general one;
+ * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it
+ * should not be freed on exit.
+ */
static int ubd_setup_common(char *str, int *index_out)
{
struct ubd *ubd_dev;
}
err = 1;
- spin_lock(&ubd_lock);
+ mutex_lock(&ubd_lock);
if(fake_major != MAJOR_NR){
printk(KERN_ERR "Can't assign a fake major twice\n");
goto out1;
major);
err = 0;
out1:
- spin_unlock(&ubd_lock);
+ mutex_unlock(&ubd_lock);
return(err);
}
}
err = 1;
- spin_lock(&ubd_lock);
+ mutex_lock(&ubd_lock);
ubd_dev = &ubd_devs[n];
if(ubd_dev->file != NULL){
ubd_dev->cow.file = backing_file;
ubd_dev->boot_openflags = flags;
out:
- spin_unlock(&ubd_lock);
+ mutex_unlock(&ubd_lock);
return(err);
}
/* Changed by ubd_handler, which is serialized because interrupts only
* happen on CPU 0.
+ * XXX: currently unused.
*/
-int intr_count = 0;
+static int intr_count = 0;
/* call ubd_finish if you need to serialize */
static void __ubd_finish(struct request *req, int error)
end_request(req, 1);
}
+/* Callable only from interrupt context - otherwise you need to do
+ * spin_lock_irq()/spin_lock_irqsave() */
static inline void ubd_finish(struct request *req, int error)
{
spin_lock(&ubd_io_lock);
spin_unlock(&ubd_io_lock);
}
-/* Called without ubd_io_lock held */
+/* XXX - move this inside ubd_intr. */
+/* Called without ubd_io_lock held, and only in interrupt context. */
static void ubd_handler(void)
{
struct io_thread_req req;
struct request *rq = elv_next_request(ubd_queue);
int n;
- do_ubd = NULL;
+ do_ubd = 0;
intr_count++;
n = os_read_file(thread_fd, &req, sizeof(req));
if(n != sizeof(req)){
ubd_finish(rq, req.error);
reactivate_fd(thread_fd, UBD_IRQ);
+ spin_lock(&ubd_io_lock);
do_ubd_request(ubd_queue);
+ spin_unlock(&ubd_io_lock);
}
static irqreturn_t ubd_intr(int irq, void *dev)
__uml_exitcall(kill_io_thread);
-static int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out)
+static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out)
{
char *file;
return(os_file_size(file, size_out));
}
-static void ubd_close(struct ubd *ubd_dev)
+static void ubd_close_dev(struct ubd *ubd_dev)
{
os_close_file(ubd_dev->fd);
if(ubd_dev->cow.file == NULL)
struct openflags flags;
char **back_ptr;
int err, create_cow, *create_ptr;
+ int fd;
ubd_dev->openflags = ubd_dev->boot_openflags;
create_cow = 0;
create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL;
back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file;
- ubd_dev->fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared,
+
+ fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared,
back_ptr, &ubd_dev->cow.bitmap_offset,
&ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset,
create_ptr);
- if((ubd_dev->fd == -ENOENT) && create_cow){
- ubd_dev->fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file,
+ if((fd == -ENOENT) && create_cow){
+ fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file,
ubd_dev->openflags, 1 << 9, PAGE_SIZE,
&ubd_dev->cow.bitmap_offset,
&ubd_dev->cow.bitmap_len,
&ubd_dev->cow.data_offset);
- if(ubd_dev->fd >= 0){
+ if(fd >= 0){
printk(KERN_INFO "Creating \"%s\" as COW file for "
"\"%s\"\n", ubd_dev->file, ubd_dev->cow.file);
}
}
- if(ubd_dev->fd < 0){
+ if(fd < 0){
printk("Failed to open '%s', errno = %d\n", ubd_dev->file,
- -ubd_dev->fd);
- return(ubd_dev->fd);
+ -fd);
+ return fd;
}
+ ubd_dev->fd = fd;
if(ubd_dev->cow.file != NULL){
err = -ENOMEM;
return(err);
}
-static int ubd_new_disk(int major, u64 size, int unit,
+static int ubd_disk_register(int major, u64 size, int unit,
struct gendisk **disk_out)
{
ubd_dev->size = ROUND_BLOCK(ubd_dev->size);
- err = ubd_new_disk(MAJOR_NR, ubd_dev->size, n, &ubd_gendisk[n]);
+ err = ubd_disk_register(MAJOR_NR, ubd_dev->size, n, &ubd_gendisk[n]);
if(err)
goto out;
if(fake_major != MAJOR_NR)
- ubd_new_disk(fake_major, ubd_dev->size, n,
+ ubd_disk_register(fake_major, ubd_dev->size, n,
&fake_gendisk[n]);
/* perhaps this should also be under the "if (fake_major)" above */
static int ubd_config(char *str)
{
- int n, err;
+ int n, ret;
str = kstrdup(str, GFP_KERNEL);
- if(str == NULL){
+ if (str == NULL) {
printk(KERN_ERR "ubd_config failed to strdup string\n");
- return(1);
+ ret = 1;
+ goto out;
}
- err = ubd_setup_common(str, &n);
- if(err){
- kfree(str);
- return(-1);
+ ret = ubd_setup_common(str, &n);
+ if (ret) {
+ ret = -1;
+ goto err_free;
+ }
+ if (n == -1) {
+ ret = 0;
+ goto err_free;
}
- if(n == -1) return(0);
- spin_lock(&ubd_lock);
- err = ubd_add(n);
- if(err)
+ mutex_lock(&ubd_lock);
+ ret = ubd_add(n);
+ if (ret)
ubd_devs[n].file = NULL;
- spin_unlock(&ubd_lock);
+ mutex_unlock(&ubd_lock);
- return(err);
+out:
+ return ret;
+
+err_free:
+ kfree(str);
+ goto out;
}
static int ubd_get_config(char *name, char *str, int size, char **error_out)
}
ubd_dev = &ubd_devs[n];
- spin_lock(&ubd_lock);
+ mutex_lock(&ubd_lock);
if(ubd_dev->file == NULL){
CONFIG_CHUNK(str, size, len, "", 1);
else CONFIG_CHUNK(str, size, len, "", 1);
out:
- spin_unlock(&ubd_lock);
+ mutex_unlock(&ubd_lock);
return(len);
}
struct ubd *ubd_dev;
int err = -ENODEV;
- spin_lock(&ubd_lock);
+ mutex_lock(&ubd_lock);
if(ubd_gendisk[n] == NULL)
goto out;
*ubd_dev = ((struct ubd) DEFAULT_UBD);
err = 0;
out:
- spin_unlock(&ubd_lock);
+ mutex_unlock(&ubd_lock);
return err;
}
+/* All these are called by mconsole in process context and without ubd-specific locks. */
static struct mc_device ubd_mc = {
.name = "ubd",
.config = ubd_config,
.remove = ubd_remove,
};
-static int ubd_mc_init(void)
+static int __init ubd_mc_init(void)
{
mconsole_register_dev(&ubd_mc);
return 0;
__initcall(ubd_mc_init);
+static int __init ubd0_init(void)
+{
+ struct ubd *ubd_dev = &ubd_devs[0];
+
+ if(ubd_dev->file == NULL)
+ ubd_dev->file = "root_fs";
+ return(0);
+}
+
+__initcall(ubd0_init);
+
static struct platform_driver ubd_driver = {
.driver = {
.name = DRIVER_NAME,
},
};
-int ubd_init(void)
+static int __init ubd_init(void)
{
int i;
late_initcall(ubd_init);
-int ubd_driver_init(void){
+static int __init ubd_driver_init(void){
unsigned long stack;
int err;
/* This should no more be needed. And it didn't work anyway to exclude
* read-write remounting of filesystems.*/
/*if((filp->f_mode & FMODE_WRITE) && !ubd_dev->openflags.w){
- if(--ubd_dev->count == 0) ubd_close(ubd_dev);
+ if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev);
err = -EROFS;
}*/
out:
struct ubd *ubd_dev = disk->private_data;
if(--ubd_dev->count == 0)
- ubd_close(ubd_dev);
+ ubd_close_dev(ubd_dev);
return(0);
}
return;
err = prepare_request(req, &io_req);
if(!err){
- do_ubd = ubd_handler;
+ do_ubd = 1;
n = os_write_file(thread_fd, (char *) &io_req,
sizeof(io_req));
if(n != sizeof(io_req))
*/
int kernel_fd = -1;
-/* Only changed by the io thread */
-int io_count = 0;
+/* Only changed by the io thread. XXX: currently unused. */
+static int io_count = 0;
int io_thread(void *arg)
{
projects / powerpc.git / blobdiff