forked from Minki/linux
[PATCH] uml: allow ubd devices to be shared in a cluster
This adds a 'c' option to the ubd switch which turns off host file locking so that the device can be shared, as with a cluster. There's also some whitespace cleanup while I was in this file. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Jeff Dike
Linus Torvalds
parent
cf9165a50a
commit
6c29256c57
@ -1,4 +1,4 @@
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/*
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/*
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* Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
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* Licensed under the GPL
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*/
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@ -71,7 +71,7 @@ struct io_thread_req {
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int error;
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};
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extern int open_ubd_file(char *file, struct openflags *openflags,
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extern int open_ubd_file(char *file, struct openflags *openflags, int shared,
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char **backing_file_out, int *bitmap_offset_out,
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unsigned long *bitmap_len_out, int *data_offset_out,
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int *create_cow_out);
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@ -137,7 +137,7 @@ static int fake_major = MAJOR_NR;
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static struct gendisk *ubd_gendisk[MAX_DEV];
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static struct gendisk *fake_gendisk[MAX_DEV];
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#ifdef CONFIG_BLK_DEV_UBD_SYNC
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#define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \
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.cl = 1 })
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@ -168,6 +168,7 @@ struct ubd {
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__u64 size;
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struct openflags boot_openflags;
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struct openflags openflags;
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int shared;
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int no_cow;
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struct cow cow;
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struct platform_device pdev;
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@ -189,6 +190,7 @@ struct ubd {
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.boot_openflags = OPEN_FLAGS, \
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.openflags = OPEN_FLAGS, \
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.no_cow = 0, \
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.shared = 0, \
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.cow = DEFAULT_COW, \
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}
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@ -305,7 +307,7 @@ static int ubd_setup_common(char *str, int *index_out)
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}
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major = simple_strtoul(str, &end, 0);
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if((*end != '\0') || (end == str)){
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printk(KERN_ERR
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printk(KERN_ERR
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"ubd_setup : didn't parse major number\n");
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return(1);
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}
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@ -316,7 +318,7 @@ static int ubd_setup_common(char *str, int *index_out)
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printk(KERN_ERR "Can't assign a fake major twice\n");
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goto out1;
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}
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fake_major = major;
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printk(KERN_INFO "Setting extra ubd major number to %d\n",
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@ -351,7 +353,7 @@ static int ubd_setup_common(char *str, int *index_out)
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if (index_out)
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*index_out = n;
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for (i = 0; i < 4; i++) {
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for (i = 0; i < sizeof("rscd="); i++) {
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switch (*str) {
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case 'r':
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flags.w = 0;
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@ -362,11 +364,14 @@ static int ubd_setup_common(char *str, int *index_out)
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case 'd':
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dev->no_cow = 1;
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break;
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case 'c':
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dev->shared = 1;
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break;
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case '=':
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str++;
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goto break_loop;
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default:
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printk(KERN_ERR "ubd_setup : Expected '=' or flag letter (r,s or d)\n");
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printk(KERN_ERR "ubd_setup : Expected '=' or flag letter (r, s, c, or d)\n");
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goto out;
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}
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str++;
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@ -515,7 +520,7 @@ static void ubd_handler(void)
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spin_unlock(&ubd_io_lock);
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return;
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}
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ubd_finish(rq, req.error);
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reactivate_fd(thread_fd, UBD_IRQ);
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do_ubd_request(ubd_queue);
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@ -532,7 +537,7 @@ static int io_pid = -1;
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void kill_io_thread(void)
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{
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if(io_pid != -1)
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if(io_pid != -1)
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os_kill_process(io_pid, 1);
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}
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@ -567,14 +572,15 @@ static int ubd_open_dev(struct ubd *dev)
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create_cow = 0;
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create_ptr = (dev->cow.file != NULL) ? &create_cow : NULL;
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back_ptr = dev->no_cow ? NULL : &dev->cow.file;
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dev->fd = open_ubd_file(dev->file, &dev->openflags, back_ptr,
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&dev->cow.bitmap_offset, &dev->cow.bitmap_len,
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&dev->cow.data_offset, create_ptr);
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dev->fd = open_ubd_file(dev->file, &dev->openflags, dev->shared,
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back_ptr, &dev->cow.bitmap_offset,
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&dev->cow.bitmap_len, &dev->cow.data_offset,
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create_ptr);
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if((dev->fd == -ENOENT) && create_cow){
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dev->fd = create_cow_file(dev->file, dev->cow.file,
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dev->fd = create_cow_file(dev->file, dev->cow.file,
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dev->openflags, 1 << 9, PAGE_SIZE,
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&dev->cow.bitmap_offset,
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&dev->cow.bitmap_offset,
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&dev->cow.bitmap_len,
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&dev->cow.data_offset);
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if(dev->fd >= 0){
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@ -598,16 +604,16 @@ static int ubd_open_dev(struct ubd *dev)
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}
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flush_tlb_kernel_vm();
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err = read_cow_bitmap(dev->fd, dev->cow.bitmap,
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dev->cow.bitmap_offset,
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err = read_cow_bitmap(dev->fd, dev->cow.bitmap,
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dev->cow.bitmap_offset,
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dev->cow.bitmap_len);
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if(err < 0)
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goto error;
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flags = dev->openflags;
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flags.w = 0;
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err = open_ubd_file(dev->cow.file, &flags, NULL, NULL, NULL,
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NULL, NULL);
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err = open_ubd_file(dev->cow.file, &flags, dev->shared, NULL,
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NULL, NULL, NULL, NULL);
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if(err < 0) goto error;
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dev->cow.fd = err;
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}
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@ -685,11 +691,11 @@ static int ubd_add(int n)
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dev->size = ROUND_BLOCK(dev->size);
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err = ubd_new_disk(MAJOR_NR, dev->size, n, &ubd_gendisk[n]);
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if(err)
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if(err)
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goto out_close;
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if(fake_major != MAJOR_NR)
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ubd_new_disk(fake_major, dev->size, n,
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ubd_new_disk(fake_major, dev->size, n,
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&fake_gendisk[n]);
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/* perhaps this should also be under the "if (fake_major)" above */
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@ -854,7 +860,7 @@ int ubd_init(void)
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return -1;
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}
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platform_driver_register(&ubd_driver);
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for (i = 0; i < MAX_DEV; i++)
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for (i = 0; i < MAX_DEV; i++)
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ubd_add(i);
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return 0;
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}
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@ -872,16 +878,16 @@ int ubd_driver_init(void){
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* enough. So use anyway the io thread. */
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}
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stack = alloc_stack(0, 0);
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io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *),
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io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *),
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&thread_fd);
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if(io_pid < 0){
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printk(KERN_ERR
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printk(KERN_ERR
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"ubd : Failed to start I/O thread (errno = %d) - "
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"falling back to synchronous I/O\n", -io_pid);
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io_pid = -1;
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return(0);
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}
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err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr,
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err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr,
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SA_INTERRUPT, "ubd", ubd_dev);
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if(err != 0)
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printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err);
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@ -978,7 +984,7 @@ static void cowify_req(struct io_thread_req *req, unsigned long *bitmap,
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if(req->op == UBD_READ) {
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for(i = 0; i < req->length >> 9; i++){
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if(ubd_test_bit(sector + i, (unsigned char *) bitmap))
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ubd_set_bit(i, (unsigned char *)
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ubd_set_bit(i, (unsigned char *)
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&req->sector_mask);
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}
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}
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@ -999,7 +1005,7 @@ static int prepare_request(struct request *req, struct io_thread_req *io_req)
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/* This should be impossible now */
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if((rq_data_dir(req) == WRITE) && !dev->openflags.w){
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printk("Write attempted on readonly ubd device %s\n",
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printk("Write attempted on readonly ubd device %s\n",
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disk->disk_name);
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end_request(req, 0);
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return(1);
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@ -1182,7 +1188,7 @@ int read_cow_bitmap(int fd, void *buf, int offset, int len)
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return(0);
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}
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int open_ubd_file(char *file, struct openflags *openflags,
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int open_ubd_file(char *file, struct openflags *openflags, int shared,
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char **backing_file_out, int *bitmap_offset_out,
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unsigned long *bitmap_len_out, int *data_offset_out,
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int *create_cow_out)
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@ -1206,10 +1212,14 @@ int open_ubd_file(char *file, struct openflags *openflags,
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return fd;
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}
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err = os_lock_file(fd, openflags->w);
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if(err < 0){
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printk("Failed to lock '%s', err = %d\n", file, -err);
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goto out_close;
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if(shared)
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printk("Not locking \"%s\" on the host\n", file);
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else {
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err = os_lock_file(fd, openflags->w);
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if(err < 0){
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printk("Failed to lock '%s', err = %d\n", file, -err);
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goto out_close;
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}
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}
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/* Succesful return case! */
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@ -1260,7 +1270,7 @@ int create_cow_file(char *cow_file, char *backing_file, struct openflags flags,
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int err, fd;
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flags.c = 1;
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fd = open_ubd_file(cow_file, &flags, NULL, NULL, NULL, NULL, NULL);
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fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL);
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if(fd < 0){
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err = fd;
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printk("Open of COW file '%s' failed, errno = %d\n", cow_file,
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