2 * Copyright (C) 2015-2016 Anton Ivanov (aivanov@brocade.com)
3 * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
4 * Licensed under the GPL
7 /* 2001-09-28...2002-04-17
8 * Partition stuff by James_McMechan@hotmail.com
9 * old style ubd by setting UBD_SHIFT to 0
10 * 2002-09-27...2002-10-18 massive tinkering for 2.5
11 * partitions have changed in 2.5
12 * 2003-01-29 more tinkering for 2.5.59-1
13 * This should now address the sysfs problems and has
14 * the symlink for devfs to allow for booting with
15 * the common /dev/ubd/discX/... names rather than
16 * only /dev/ubdN/discN this version also has lots of
17 * clean ups preparing for ubd-many.
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/blkdev.h>
26 #include <linux/ata.h>
27 #include <linux/hdreg.h>
28 #include <linux/cdrom.h>
29 #include <linux/proc_fs.h>
30 #include <linux/seq_file.h>
31 #include <linux/ctype.h>
32 #include <linux/slab.h>
33 #include <linux/vmalloc.h>
34 #include <linux/platform_device.h>
35 #include <linux/scatterlist.h>
36 #include <asm/tlbflush.h>
37 #include <kern_util.h>
38 #include "mconsole_kern.h"
45 enum ubd_req
{ UBD_READ
, UBD_WRITE
, UBD_FLUSH
};
47 struct io_thread_req
{
51 unsigned long offsets
[2];
52 unsigned long long offset
;
56 unsigned long sector_mask
;
57 unsigned long long cow_offset
;
58 unsigned long bitmap_words
[2];
63 static struct io_thread_req
* (*irq_req_buffer
)[];
64 static struct io_thread_req
*irq_remainder
;
65 static int irq_remainder_size
;
67 static struct io_thread_req
* (*io_req_buffer
)[];
68 static struct io_thread_req
*io_remainder
;
69 static int io_remainder_size
;
73 static inline int ubd_test_bit(__u64 bit
, unsigned char *data
)
78 bits
= sizeof(data
[0]) * 8;
81 return (data
[n
] & (1 << off
)) != 0;
84 static inline void ubd_set_bit(__u64 bit
, unsigned char *data
)
89 bits
= sizeof(data
[0]) * 8;
92 data
[n
] |= (1 << off
);
94 /*End stuff from ubd_user.h*/
96 #define DRIVER_NAME "uml-blkdev"
98 static DEFINE_MUTEX(ubd_lock
);
99 static DEFINE_MUTEX(ubd_mutex
); /* replaces BKL, might not be needed */
101 static int ubd_open(struct block_device
*bdev
, fmode_t mode
);
102 static void ubd_release(struct gendisk
*disk
, fmode_t mode
);
103 static int ubd_ioctl(struct block_device
*bdev
, fmode_t mode
,
104 unsigned int cmd
, unsigned long arg
);
105 static int ubd_getgeo(struct block_device
*bdev
, struct hd_geometry
*geo
);
109 static const struct block_device_operations ubd_blops
= {
110 .owner
= THIS_MODULE
,
112 .release
= ubd_release
,
114 .getgeo
= ubd_getgeo
,
117 /* Protected by ubd_lock */
118 static int fake_major
= UBD_MAJOR
;
119 static struct gendisk
*ubd_gendisk
[MAX_DEV
];
120 static struct gendisk
*fake_gendisk
[MAX_DEV
];
122 #ifdef CONFIG_BLK_DEV_UBD_SYNC
123 #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \
126 #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \
129 static struct openflags global_openflags
= OPEN_FLAGS
;
132 /* backing file name */
134 /* backing file fd */
136 unsigned long *bitmap
;
137 unsigned long bitmap_len
;
145 struct list_head restart
;
146 /* name (and fd, below) of the file opened for writing, either the
147 * backing or the cow file. */
152 struct openflags boot_openflags
;
153 struct openflags openflags
;
157 struct platform_device pdev
;
158 struct request_queue
*queue
;
160 struct scatterlist sg
[MAX_SG
];
161 struct request
*request
;
162 int start_sg
, end_sg
;
166 #define DEFAULT_COW { \
170 .bitmap_offset = 0, \
174 #define DEFAULT_UBD { \
179 .boot_openflags = OPEN_FLAGS, \
180 .openflags = OPEN_FLAGS, \
183 .cow = DEFAULT_COW, \
184 .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \
191 /* Protected by ubd_lock */
192 static struct ubd ubd_devs
[MAX_DEV
] = { [0 ... MAX_DEV
- 1] = DEFAULT_UBD
};
194 /* Only changed by fake_ide_setup which is a setup */
195 static int fake_ide
= 0;
196 static struct proc_dir_entry
*proc_ide_root
= NULL
;
197 static struct proc_dir_entry
*proc_ide
= NULL
;
199 static void make_proc_ide(void)
201 proc_ide_root
= proc_mkdir("ide", NULL
);
202 proc_ide
= proc_mkdir("ide0", proc_ide_root
);
205 static int fake_ide_media_proc_show(struct seq_file
*m
, void *v
)
207 seq_puts(m
, "disk\n");
211 static void make_ide_entries(const char *dev_name
)
213 struct proc_dir_entry
*dir
, *ent
;
216 if(proc_ide_root
== NULL
) make_proc_ide();
218 dir
= proc_mkdir(dev_name
, proc_ide
);
221 ent
= proc_create_single("media", S_IRUGO
, dir
,
222 fake_ide_media_proc_show
);
224 snprintf(name
, sizeof(name
), "ide0/%s", dev_name
);
225 proc_symlink(dev_name
, proc_ide_root
, name
);
228 static int fake_ide_setup(char *str
)
234 __setup("fake_ide", fake_ide_setup
);
236 __uml_help(fake_ide_setup
,
238 " Create ide0 entries that map onto ubd devices.\n\n"
241 static int parse_unit(char **ptr
)
243 char *str
= *ptr
, *end
;
247 n
= simple_strtoul(str
, &end
, 0);
252 else if (('a' <= *str
) && (*str
<= 'z')) {
260 /* If *index_out == -1 at exit, the passed option was a general one;
261 * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it
262 * should not be freed on exit.
264 static int ubd_setup_common(char *str
, int *index_out
, char **error_out
)
267 struct openflags flags
= global_openflags
;
271 if(index_out
) *index_out
= -1;
278 if(!strcmp(str
, "sync")){
279 global_openflags
= of_sync(global_openflags
);
284 major
= simple_strtoul(str
, &end
, 0);
285 if((*end
!= '\0') || (end
== str
)){
286 *error_out
= "Didn't parse major number";
290 mutex_lock(&ubd_lock
);
291 if (fake_major
!= UBD_MAJOR
) {
292 *error_out
= "Can't assign a fake major twice";
298 printk(KERN_INFO
"Setting extra ubd major number to %d\n",
302 mutex_unlock(&ubd_lock
);
306 n
= parse_unit(&str
);
308 *error_out
= "Couldn't parse device number";
312 *error_out
= "Device number out of range";
317 mutex_lock(&ubd_lock
);
319 ubd_dev
= &ubd_devs
[n
];
320 if(ubd_dev
->file
!= NULL
){
321 *error_out
= "Device is already configured";
329 for (i
= 0; i
< sizeof("rscd="); i
++) {
347 *error_out
= "Expected '=' or flag letter "
355 *error_out
= "Too many flags specified";
357 *error_out
= "Missing '='";
361 backing_file
= strchr(str
, ',');
363 if (backing_file
== NULL
)
364 backing_file
= strchr(str
, ':');
366 if(backing_file
!= NULL
){
368 *error_out
= "Can't specify both 'd' and a cow file";
372 *backing_file
= '\0';
378 ubd_dev
->cow
.file
= backing_file
;
379 ubd_dev
->boot_openflags
= flags
;
381 mutex_unlock(&ubd_lock
);
385 static int ubd_setup(char *str
)
390 err
= ubd_setup_common(str
, NULL
, &error
);
392 printk(KERN_ERR
"Failed to initialize device with \"%s\" : "
397 __setup("ubd", ubd_setup
);
398 __uml_help(ubd_setup
,
399 "ubd<n><flags>=<filename>[(:|,)<filename2>]\n"
400 " This is used to associate a device with a file in the underlying\n"
401 " filesystem. When specifying two filenames, the first one is the\n"
402 " COW name and the second is the backing file name. As separator you can\n"
403 " use either a ':' or a ',': the first one allows writing things like;\n"
404 " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n"
405 " while with a ',' the shell would not expand the 2nd '~'.\n"
406 " When using only one filename, UML will detect whether to treat it like\n"
407 " a COW file or a backing file. To override this detection, add the 'd'\n"
409 " ubd0d=BackingFile\n"
410 " Usually, there is a filesystem in the file, but \n"
411 " that's not required. Swap devices containing swap files can be\n"
412 " specified like this. Also, a file which doesn't contain a\n"
413 " filesystem can have its contents read in the virtual \n"
414 " machine by running 'dd' on the device. <n> must be in the range\n"
415 " 0 to 7. Appending an 'r' to the number will cause that device\n"
416 " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n"
417 " an 's' will cause data to be written to disk on the host immediately.\n"
418 " 'c' will cause the device to be treated as being shared between multiple\n"
419 " UMLs and file locking will be turned off - this is appropriate for a\n"
420 " cluster filesystem and inappropriate at almost all other times.\n\n"
423 static int udb_setup(char *str
)
425 printk("udb%s specified on command line is almost certainly a ubd -> "
430 __setup("udb", udb_setup
);
431 __uml_help(udb_setup
,
433 " This option is here solely to catch ubd -> udb typos, which can be\n"
434 " to impossible to catch visually unless you specifically look for\n"
435 " them. The only result of any option starting with 'udb' is an error\n"
436 " in the boot output.\n\n"
439 static void do_ubd_request(struct request_queue
* q
);
441 /* Only changed by ubd_init, which is an initcall. */
442 static int thread_fd
= -1;
443 static LIST_HEAD(restart
);
445 /* Function to read several request pointers at a time
446 * handling fractional reads if (and as) needed
449 static int bulk_req_safe_read(
451 struct io_thread_req
* (*request_buffer
)[],
452 struct io_thread_req
**remainder
,
460 if (*remainder_size
> 0) {
462 (char *) request_buffer
,
463 (char *) remainder
, *remainder_size
470 ((char *) request_buffer
) + *remainder_size
,
471 sizeof(struct io_thread_req
*)*max_recs
476 if ((n
% sizeof(struct io_thread_req
*)) > 0) {
478 * Read somehow returned not a multiple of dword
479 * theoretically possible, but never observed in the
480 * wild, so read routine must be able to handle it
482 *remainder_size
= n
% sizeof(struct io_thread_req
*);
483 WARN(*remainder_size
> 0, "UBD IPC read returned a partial result");
486 ((char *) request_buffer
) +
487 (n
/sizeof(struct io_thread_req
*))*sizeof(struct io_thread_req
*),
490 n
= n
- *remainder_size
;
498 /* Called without dev->lock held, and only in interrupt context. */
499 static void ubd_handler(void)
502 struct list_head
*list
, *next_ele
;
508 n
= bulk_req_safe_read(
518 printk(KERN_ERR
"spurious interrupt in ubd_handler, "
522 for (count
= 0; count
< n
/sizeof(struct io_thread_req
*); count
++) {
524 (*irq_req_buffer
)[count
]->req
,
526 (*irq_req_buffer
)[count
]->length
528 kfree((*irq_req_buffer
)[count
]);
531 reactivate_fd(thread_fd
, UBD_IRQ
);
533 list_for_each_safe(list
, next_ele
, &restart
){
534 ubd
= container_of(list
, struct ubd
, restart
);
535 list_del_init(&ubd
->restart
);
536 spin_lock_irqsave(&ubd
->lock
, flags
);
537 do_ubd_request(ubd
->queue
);
538 spin_unlock_irqrestore(&ubd
->lock
, flags
);
542 static irqreturn_t
ubd_intr(int irq
, void *dev
)
548 /* Only changed by ubd_init, which is an initcall. */
549 static int io_pid
= -1;
551 static void kill_io_thread(void)
554 os_kill_process(io_pid
, 1);
557 __uml_exitcall(kill_io_thread
);
559 static inline int ubd_file_size(struct ubd
*ubd_dev
, __u64
*size_out
)
569 unsigned long long size
;
573 if (ubd_dev
->file
&& ubd_dev
->cow
.file
) {
574 file
= ubd_dev
->cow
.file
;
579 fd
= os_open_file(ubd_dev
->file
, of_read(OPENFLAGS()), 0);
583 err
= read_cow_header(file_reader
, &fd
, &version
, &backing_file
, \
584 &mtime
, &size
, §or_size
, &align
, &bitmap_offset
);
588 file
= ubd_dev
->file
;
593 return os_file_size(file
, size_out
);
596 static int read_cow_bitmap(int fd
, void *buf
, int offset
, int len
)
600 err
= os_pread_file(fd
, buf
, len
, offset
);
607 static int backing_file_mismatch(char *file
, __u64 size
, time_t mtime
)
609 unsigned long modtime
;
610 unsigned long long actual
;
613 err
= os_file_modtime(file
, &modtime
);
615 printk(KERN_ERR
"Failed to get modification time of backing "
616 "file \"%s\", err = %d\n", file
, -err
);
620 err
= os_file_size(file
, &actual
);
622 printk(KERN_ERR
"Failed to get size of backing file \"%s\", "
623 "err = %d\n", file
, -err
);
627 if (actual
!= size
) {
628 /*__u64 can be a long on AMD64 and with %lu GCC complains; so
630 printk(KERN_ERR
"Size mismatch (%llu vs %llu) of COW header "
631 "vs backing file\n", (unsigned long long) size
, actual
);
634 if (modtime
!= mtime
) {
635 printk(KERN_ERR
"mtime mismatch (%ld vs %ld) of COW header vs "
636 "backing file\n", mtime
, modtime
);
642 static int path_requires_switch(char *from_cmdline
, char *from_cow
, char *cow
)
644 struct uml_stat buf1
, buf2
;
647 if (from_cmdline
== NULL
)
649 if (!strcmp(from_cmdline
, from_cow
))
652 err
= os_stat_file(from_cmdline
, &buf1
);
654 printk(KERN_ERR
"Couldn't stat '%s', err = %d\n", from_cmdline
,
658 err
= os_stat_file(from_cow
, &buf2
);
660 printk(KERN_ERR
"Couldn't stat '%s', err = %d\n", from_cow
,
664 if ((buf1
.ust_dev
== buf2
.ust_dev
) && (buf1
.ust_ino
== buf2
.ust_ino
))
667 printk(KERN_ERR
"Backing file mismatch - \"%s\" requested, "
668 "\"%s\" specified in COW header of \"%s\"\n",
669 from_cmdline
, from_cow
, cow
);
673 static int open_ubd_file(char *file
, struct openflags
*openflags
, int shared
,
674 char **backing_file_out
, int *bitmap_offset_out
,
675 unsigned long *bitmap_len_out
, int *data_offset_out
,
679 unsigned long long size
;
680 __u32 version
, align
;
682 int fd
, err
, sectorsize
, asked_switch
, mode
= 0644;
684 fd
= os_open_file(file
, *openflags
, mode
);
686 if ((fd
== -ENOENT
) && (create_cow_out
!= NULL
))
689 ((fd
!= -EROFS
) && (fd
!= -EACCES
)))
692 fd
= os_open_file(file
, *openflags
, mode
);
698 printk(KERN_INFO
"Not locking \"%s\" on the host\n", file
);
700 err
= os_lock_file(fd
, openflags
->w
);
702 printk(KERN_ERR
"Failed to lock '%s', err = %d\n",
708 /* Successful return case! */
709 if (backing_file_out
== NULL
)
712 err
= read_cow_header(file_reader
, &fd
, &version
, &backing_file
, &mtime
,
713 &size
, §orsize
, &align
, bitmap_offset_out
);
714 if (err
&& (*backing_file_out
!= NULL
)) {
715 printk(KERN_ERR
"Failed to read COW header from COW file "
716 "\"%s\", errno = %d\n", file
, -err
);
722 asked_switch
= path_requires_switch(*backing_file_out
, backing_file
,
725 /* Allow switching only if no mismatch. */
726 if (asked_switch
&& !backing_file_mismatch(*backing_file_out
, size
,
728 printk(KERN_ERR
"Switching backing file to '%s'\n",
730 err
= write_cow_header(file
, fd
, *backing_file_out
,
731 sectorsize
, align
, &size
);
733 printk(KERN_ERR
"Switch failed, errno = %d\n", -err
);
737 *backing_file_out
= backing_file
;
738 err
= backing_file_mismatch(*backing_file_out
, size
, mtime
);
743 cow_sizes(version
, size
, sectorsize
, align
, *bitmap_offset_out
,
744 bitmap_len_out
, data_offset_out
);
752 static int create_cow_file(char *cow_file
, char *backing_file
,
753 struct openflags flags
,
754 int sectorsize
, int alignment
, int *bitmap_offset_out
,
755 unsigned long *bitmap_len_out
, int *data_offset_out
)
760 fd
= open_ubd_file(cow_file
, &flags
, 0, NULL
, NULL
, NULL
, NULL
, NULL
);
763 printk(KERN_ERR
"Open of COW file '%s' failed, errno = %d\n",
768 err
= init_cow_file(fd
, cow_file
, backing_file
, sectorsize
, alignment
,
769 bitmap_offset_out
, bitmap_len_out
,
778 static void ubd_close_dev(struct ubd
*ubd_dev
)
780 os_close_file(ubd_dev
->fd
);
781 if(ubd_dev
->cow
.file
== NULL
)
784 os_close_file(ubd_dev
->cow
.fd
);
785 vfree(ubd_dev
->cow
.bitmap
);
786 ubd_dev
->cow
.bitmap
= NULL
;
789 static int ubd_open_dev(struct ubd
*ubd_dev
)
791 struct openflags flags
;
793 int err
, create_cow
, *create_ptr
;
796 ubd_dev
->openflags
= ubd_dev
->boot_openflags
;
798 create_ptr
= (ubd_dev
->cow
.file
!= NULL
) ? &create_cow
: NULL
;
799 back_ptr
= ubd_dev
->no_cow
? NULL
: &ubd_dev
->cow
.file
;
801 fd
= open_ubd_file(ubd_dev
->file
, &ubd_dev
->openflags
, ubd_dev
->shared
,
802 back_ptr
, &ubd_dev
->cow
.bitmap_offset
,
803 &ubd_dev
->cow
.bitmap_len
, &ubd_dev
->cow
.data_offset
,
806 if((fd
== -ENOENT
) && create_cow
){
807 fd
= create_cow_file(ubd_dev
->file
, ubd_dev
->cow
.file
,
808 ubd_dev
->openflags
, 1 << 9, PAGE_SIZE
,
809 &ubd_dev
->cow
.bitmap_offset
,
810 &ubd_dev
->cow
.bitmap_len
,
811 &ubd_dev
->cow
.data_offset
);
813 printk(KERN_INFO
"Creating \"%s\" as COW file for "
814 "\"%s\"\n", ubd_dev
->file
, ubd_dev
->cow
.file
);
819 printk("Failed to open '%s', errno = %d\n", ubd_dev
->file
,
825 if(ubd_dev
->cow
.file
!= NULL
){
826 blk_queue_max_hw_sectors(ubd_dev
->queue
, 8 * sizeof(long));
829 ubd_dev
->cow
.bitmap
= vmalloc(ubd_dev
->cow
.bitmap_len
);
830 if(ubd_dev
->cow
.bitmap
== NULL
){
831 printk(KERN_ERR
"Failed to vmalloc COW bitmap\n");
834 flush_tlb_kernel_vm();
836 err
= read_cow_bitmap(ubd_dev
->fd
, ubd_dev
->cow
.bitmap
,
837 ubd_dev
->cow
.bitmap_offset
,
838 ubd_dev
->cow
.bitmap_len
);
842 flags
= ubd_dev
->openflags
;
844 err
= open_ubd_file(ubd_dev
->cow
.file
, &flags
, ubd_dev
->shared
, NULL
,
845 NULL
, NULL
, NULL
, NULL
);
846 if(err
< 0) goto error
;
847 ubd_dev
->cow
.fd
= err
;
851 os_close_file(ubd_dev
->fd
);
855 static void ubd_device_release(struct device
*dev
)
857 struct ubd
*ubd_dev
= dev_get_drvdata(dev
);
859 blk_cleanup_queue(ubd_dev
->queue
);
860 *ubd_dev
= ((struct ubd
) DEFAULT_UBD
);
863 static int ubd_disk_register(int major
, u64 size
, int unit
,
864 struct gendisk
**disk_out
)
866 struct device
*parent
= NULL
;
867 struct gendisk
*disk
;
869 disk
= alloc_disk(1 << UBD_SHIFT
);
874 disk
->first_minor
= unit
<< UBD_SHIFT
;
875 disk
->fops
= &ubd_blops
;
876 set_capacity(disk
, size
/ 512);
877 if (major
== UBD_MAJOR
)
878 sprintf(disk
->disk_name
, "ubd%c", 'a' + unit
);
880 sprintf(disk
->disk_name
, "ubd_fake%d", unit
);
882 /* sysfs register (not for ide fake devices) */
883 if (major
== UBD_MAJOR
) {
884 ubd_devs
[unit
].pdev
.id
= unit
;
885 ubd_devs
[unit
].pdev
.name
= DRIVER_NAME
;
886 ubd_devs
[unit
].pdev
.dev
.release
= ubd_device_release
;
887 dev_set_drvdata(&ubd_devs
[unit
].pdev
.dev
, &ubd_devs
[unit
]);
888 platform_device_register(&ubd_devs
[unit
].pdev
);
889 parent
= &ubd_devs
[unit
].pdev
.dev
;
892 disk
->private_data
= &ubd_devs
[unit
];
893 disk
->queue
= ubd_devs
[unit
].queue
;
894 device_add_disk(parent
, disk
);
900 #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9))
902 static int ubd_add(int n
, char **error_out
)
904 struct ubd
*ubd_dev
= &ubd_devs
[n
];
907 if(ubd_dev
->file
== NULL
)
910 err
= ubd_file_size(ubd_dev
, &ubd_dev
->size
);
912 *error_out
= "Couldn't determine size of device's file";
916 ubd_dev
->size
= ROUND_BLOCK(ubd_dev
->size
);
918 INIT_LIST_HEAD(&ubd_dev
->restart
);
919 sg_init_table(ubd_dev
->sg
, MAX_SG
);
922 ubd_dev
->queue
= blk_init_queue(do_ubd_request
, &ubd_dev
->lock
);
923 if (ubd_dev
->queue
== NULL
) {
924 *error_out
= "Failed to initialize device queue";
927 ubd_dev
->queue
->queuedata
= ubd_dev
;
928 blk_queue_write_cache(ubd_dev
->queue
, true, false);
930 blk_queue_max_segments(ubd_dev
->queue
, MAX_SG
);
931 err
= ubd_disk_register(UBD_MAJOR
, ubd_dev
->size
, n
, &ubd_gendisk
[n
]);
933 *error_out
= "Failed to register device";
937 if (fake_major
!= UBD_MAJOR
)
938 ubd_disk_register(fake_major
, ubd_dev
->size
, n
,
942 * Perhaps this should also be under the "if (fake_major)" above
943 * using the fake_disk->disk_name
946 make_ide_entries(ubd_gendisk
[n
]->disk_name
);
953 blk_cleanup_queue(ubd_dev
->queue
);
957 static int ubd_config(char *str
, char **error_out
)
961 /* This string is possibly broken up and stored, so it's only
962 * freed if ubd_setup_common fails, or if only general options
965 str
= kstrdup(str
, GFP_KERNEL
);
967 *error_out
= "Failed to allocate memory";
971 ret
= ubd_setup_common(str
, &n
, error_out
);
980 mutex_lock(&ubd_lock
);
981 ret
= ubd_add(n
, error_out
);
983 ubd_devs
[n
].file
= NULL
;
984 mutex_unlock(&ubd_lock
);
994 static int ubd_get_config(char *name
, char *str
, int size
, char **error_out
)
999 n
= parse_unit(&name
);
1000 if((n
>= MAX_DEV
) || (n
< 0)){
1001 *error_out
= "ubd_get_config : device number out of range";
1005 ubd_dev
= &ubd_devs
[n
];
1006 mutex_lock(&ubd_lock
);
1008 if(ubd_dev
->file
== NULL
){
1009 CONFIG_CHUNK(str
, size
, len
, "", 1);
1013 CONFIG_CHUNK(str
, size
, len
, ubd_dev
->file
, 0);
1015 if(ubd_dev
->cow
.file
!= NULL
){
1016 CONFIG_CHUNK(str
, size
, len
, ",", 0);
1017 CONFIG_CHUNK(str
, size
, len
, ubd_dev
->cow
.file
, 1);
1019 else CONFIG_CHUNK(str
, size
, len
, "", 1);
1022 mutex_unlock(&ubd_lock
);
1026 static int ubd_id(char **str
, int *start_out
, int *end_out
)
1030 n
= parse_unit(str
);
1032 *end_out
= MAX_DEV
- 1;
1036 static int ubd_remove(int n
, char **error_out
)
1038 struct gendisk
*disk
= ubd_gendisk
[n
];
1039 struct ubd
*ubd_dev
;
1042 mutex_lock(&ubd_lock
);
1044 ubd_dev
= &ubd_devs
[n
];
1046 if(ubd_dev
->file
== NULL
)
1049 /* you cannot remove a open disk */
1051 if(ubd_dev
->count
> 0)
1054 ubd_gendisk
[n
] = NULL
;
1060 if(fake_gendisk
[n
] != NULL
){
1061 del_gendisk(fake_gendisk
[n
]);
1062 put_disk(fake_gendisk
[n
]);
1063 fake_gendisk
[n
] = NULL
;
1067 platform_device_unregister(&ubd_dev
->pdev
);
1069 mutex_unlock(&ubd_lock
);
1073 /* All these are called by mconsole in process context and without
1074 * ubd-specific locks. The structure itself is const except for .list.
1076 static struct mc_device ubd_mc
= {
1077 .list
= LIST_HEAD_INIT(ubd_mc
.list
),
1079 .config
= ubd_config
,
1080 .get_config
= ubd_get_config
,
1082 .remove
= ubd_remove
,
1085 static int __init
ubd_mc_init(void)
1087 mconsole_register_dev(&ubd_mc
);
1091 __initcall(ubd_mc_init
);
1093 static int __init
ubd0_init(void)
1095 struct ubd
*ubd_dev
= &ubd_devs
[0];
1097 mutex_lock(&ubd_lock
);
1098 if(ubd_dev
->file
== NULL
)
1099 ubd_dev
->file
= "root_fs";
1100 mutex_unlock(&ubd_lock
);
1105 __initcall(ubd0_init
);
1107 /* Used in ubd_init, which is an initcall */
1108 static struct platform_driver ubd_driver
= {
1110 .name
= DRIVER_NAME
,
1114 static int __init
ubd_init(void)
1119 if (register_blkdev(UBD_MAJOR
, "ubd"))
1122 if (fake_major
!= UBD_MAJOR
) {
1123 char name
[sizeof("ubd_nnn\0")];
1125 snprintf(name
, sizeof(name
), "ubd_%d", fake_major
);
1126 if (register_blkdev(fake_major
, "ubd"))
1130 irq_req_buffer
= kmalloc_array(UBD_REQ_BUFFER_SIZE
,
1131 sizeof(struct io_thread_req
*),
1136 if (irq_req_buffer
== NULL
) {
1137 printk(KERN_ERR
"Failed to initialize ubd buffering\n");
1140 io_req_buffer
= kmalloc_array(UBD_REQ_BUFFER_SIZE
,
1141 sizeof(struct io_thread_req
*),
1147 if (io_req_buffer
== NULL
) {
1148 printk(KERN_ERR
"Failed to initialize ubd buffering\n");
1151 platform_driver_register(&ubd_driver
);
1152 mutex_lock(&ubd_lock
);
1153 for (i
= 0; i
< MAX_DEV
; i
++){
1154 err
= ubd_add(i
, &error
);
1156 printk(KERN_ERR
"Failed to initialize ubd device %d :"
1159 mutex_unlock(&ubd_lock
);
1163 late_initcall(ubd_init
);
1165 static int __init
ubd_driver_init(void){
1166 unsigned long stack
;
1169 /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/
1170 if(global_openflags
.s
){
1171 printk(KERN_INFO
"ubd: Synchronous mode\n");
1172 /* Letting ubd=sync be like using ubd#s= instead of ubd#= is
1173 * enough. So use anyway the io thread. */
1175 stack
= alloc_stack(0, 0);
1176 io_pid
= start_io_thread(stack
+ PAGE_SIZE
- sizeof(void *),
1180 "ubd : Failed to start I/O thread (errno = %d) - "
1181 "falling back to synchronous I/O\n", -io_pid
);
1185 err
= um_request_irq(UBD_IRQ
, thread_fd
, IRQ_READ
, ubd_intr
,
1186 0, "ubd", ubd_devs
);
1188 printk(KERN_ERR
"um_request_irq failed - errno = %d\n", -err
);
1192 device_initcall(ubd_driver_init
);
1194 static int ubd_open(struct block_device
*bdev
, fmode_t mode
)
1196 struct gendisk
*disk
= bdev
->bd_disk
;
1197 struct ubd
*ubd_dev
= disk
->private_data
;
1200 mutex_lock(&ubd_mutex
);
1201 if(ubd_dev
->count
== 0){
1202 err
= ubd_open_dev(ubd_dev
);
1204 printk(KERN_ERR
"%s: Can't open \"%s\": errno = %d\n",
1205 disk
->disk_name
, ubd_dev
->file
, -err
);
1210 set_disk_ro(disk
, !ubd_dev
->openflags
.w
);
1212 /* This should no more be needed. And it didn't work anyway to exclude
1213 * read-write remounting of filesystems.*/
1214 /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){
1215 if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev);
1219 mutex_unlock(&ubd_mutex
);
1223 static void ubd_release(struct gendisk
*disk
, fmode_t mode
)
1225 struct ubd
*ubd_dev
= disk
->private_data
;
1227 mutex_lock(&ubd_mutex
);
1228 if(--ubd_dev
->count
== 0)
1229 ubd_close_dev(ubd_dev
);
1230 mutex_unlock(&ubd_mutex
);
1233 static void cowify_bitmap(__u64 io_offset
, int length
, unsigned long *cow_mask
,
1234 __u64
*cow_offset
, unsigned long *bitmap
,
1235 __u64 bitmap_offset
, unsigned long *bitmap_words
,
1238 __u64 sector
= io_offset
>> 9;
1239 int i
, update_bitmap
= 0;
1241 for(i
= 0; i
< length
>> 9; i
++){
1242 if(cow_mask
!= NULL
)
1243 ubd_set_bit(i
, (unsigned char *) cow_mask
);
1244 if(ubd_test_bit(sector
+ i
, (unsigned char *) bitmap
))
1248 ubd_set_bit(sector
+ i
, (unsigned char *) bitmap
);
1254 *cow_offset
= sector
/ (sizeof(unsigned long) * 8);
1256 /* This takes care of the case where we're exactly at the end of the
1257 * device, and *cow_offset + 1 is off the end. So, just back it up
1258 * by one word. Thanks to Lynn Kerby for the fix and James McMechan
1259 * for the original diagnosis.
1261 if (*cow_offset
== (DIV_ROUND_UP(bitmap_len
,
1262 sizeof(unsigned long)) - 1))
1265 bitmap_words
[0] = bitmap
[*cow_offset
];
1266 bitmap_words
[1] = bitmap
[*cow_offset
+ 1];
1268 *cow_offset
*= sizeof(unsigned long);
1269 *cow_offset
+= bitmap_offset
;
1272 static void cowify_req(struct io_thread_req
*req
, unsigned long *bitmap
,
1273 __u64 bitmap_offset
, __u64 bitmap_len
)
1275 __u64 sector
= req
->offset
>> 9;
1278 if(req
->length
> (sizeof(req
->sector_mask
) * 8) << 9)
1279 panic("Operation too long");
1281 if(req
->op
== UBD_READ
) {
1282 for(i
= 0; i
< req
->length
>> 9; i
++){
1283 if(ubd_test_bit(sector
+ i
, (unsigned char *) bitmap
))
1284 ubd_set_bit(i
, (unsigned char *)
1288 else cowify_bitmap(req
->offset
, req
->length
, &req
->sector_mask
,
1289 &req
->cow_offset
, bitmap
, bitmap_offset
,
1290 req
->bitmap_words
, bitmap_len
);
1293 /* Called with dev->lock held */
1294 static void prepare_request(struct request
*req
, struct io_thread_req
*io_req
,
1295 unsigned long long offset
, int page_offset
,
1296 int len
, struct page
*page
)
1298 struct gendisk
*disk
= req
->rq_disk
;
1299 struct ubd
*ubd_dev
= disk
->private_data
;
1302 io_req
->fds
[0] = (ubd_dev
->cow
.file
!= NULL
) ? ubd_dev
->cow
.fd
:
1304 io_req
->fds
[1] = ubd_dev
->fd
;
1305 io_req
->cow_offset
= -1;
1306 io_req
->offset
= offset
;
1307 io_req
->length
= len
;
1309 io_req
->sector_mask
= 0;
1311 io_req
->op
= (rq_data_dir(req
) == READ
) ? UBD_READ
: UBD_WRITE
;
1312 io_req
->offsets
[0] = 0;
1313 io_req
->offsets
[1] = ubd_dev
->cow
.data_offset
;
1314 io_req
->buffer
= page_address(page
) + page_offset
;
1315 io_req
->sectorsize
= 1 << 9;
1317 if(ubd_dev
->cow
.file
!= NULL
)
1318 cowify_req(io_req
, ubd_dev
->cow
.bitmap
,
1319 ubd_dev
->cow
.bitmap_offset
, ubd_dev
->cow
.bitmap_len
);
1323 /* Called with dev->lock held */
1324 static void prepare_flush_request(struct request
*req
,
1325 struct io_thread_req
*io_req
)
1327 struct gendisk
*disk
= req
->rq_disk
;
1328 struct ubd
*ubd_dev
= disk
->private_data
;
1331 io_req
->fds
[0] = (ubd_dev
->cow
.file
!= NULL
) ? ubd_dev
->cow
.fd
:
1333 io_req
->op
= UBD_FLUSH
;
1336 static bool submit_request(struct io_thread_req
*io_req
, struct ubd
*dev
)
1338 int n
= os_write_file(thread_fd
, &io_req
,
1340 if (n
!= sizeof(io_req
)) {
1342 printk("write to io thread failed, "
1343 "errno = %d\n", -n
);
1344 else if (list_empty(&dev
->restart
))
1345 list_add(&dev
->restart
, &restart
);
1353 /* Called with dev->lock held */
1354 static void do_ubd_request(struct request_queue
*q
)
1356 struct io_thread_req
*io_req
;
1357 struct request
*req
;
1360 struct ubd
*dev
= q
->queuedata
;
1361 if(dev
->request
== NULL
){
1362 struct request
*req
= blk_fetch_request(q
);
1367 dev
->rq_pos
= blk_rq_pos(req
);
1369 dev
->end_sg
= blk_rq_map_sg(q
, req
, dev
->sg
);
1374 if (req_op(req
) == REQ_OP_FLUSH
) {
1375 io_req
= kmalloc(sizeof(struct io_thread_req
),
1377 if (io_req
== NULL
) {
1378 if (list_empty(&dev
->restart
))
1379 list_add(&dev
->restart
, &restart
);
1382 prepare_flush_request(req
, io_req
);
1383 if (submit_request(io_req
, dev
) == false)
1387 while(dev
->start_sg
< dev
->end_sg
){
1388 struct scatterlist
*sg
= &dev
->sg
[dev
->start_sg
];
1390 io_req
= kmalloc(sizeof(struct io_thread_req
),
1393 if(list_empty(&dev
->restart
))
1394 list_add(&dev
->restart
, &restart
);
1397 prepare_request(req
, io_req
,
1398 (unsigned long long)dev
->rq_pos
<< 9,
1399 sg
->offset
, sg
->length
, sg_page(sg
));
1401 if (submit_request(io_req
, dev
) == false)
1404 dev
->rq_pos
+= sg
->length
>> 9;
1408 dev
->request
= NULL
;
1412 static int ubd_getgeo(struct block_device
*bdev
, struct hd_geometry
*geo
)
1414 struct ubd
*ubd_dev
= bdev
->bd_disk
->private_data
;
1418 geo
->cylinders
= ubd_dev
->size
/ (128 * 32 * 512);
1422 static int ubd_ioctl(struct block_device
*bdev
, fmode_t mode
,
1423 unsigned int cmd
, unsigned long arg
)
1425 struct ubd
*ubd_dev
= bdev
->bd_disk
->private_data
;
1426 u16 ubd_id
[ATA_ID_WORDS
];
1429 struct cdrom_volctrl volume
;
1430 case HDIO_GET_IDENTITY
:
1431 memset(&ubd_id
, 0, ATA_ID_WORDS
* 2);
1432 ubd_id
[ATA_ID_CYLS
] = ubd_dev
->size
/ (128 * 32 * 512);
1433 ubd_id
[ATA_ID_HEADS
] = 128;
1434 ubd_id
[ATA_ID_SECTORS
] = 32;
1435 if(copy_to_user((char __user
*) arg
, (char *) &ubd_id
,
1441 if(copy_from_user(&volume
, (char __user
*) arg
, sizeof(volume
)))
1443 volume
.channel0
= 255;
1444 volume
.channel1
= 255;
1445 volume
.channel2
= 255;
1446 volume
.channel3
= 255;
1447 if(copy_to_user((char __user
*) arg
, &volume
, sizeof(volume
)))
1454 static int update_bitmap(struct io_thread_req
*req
)
1458 if(req
->cow_offset
== -1)
1461 n
= os_pwrite_file(req
->fds
[1], &req
->bitmap_words
,
1462 sizeof(req
->bitmap_words
), req
->cow_offset
);
1463 if(n
!= sizeof(req
->bitmap_words
)){
1464 printk("do_io - bitmap update failed, err = %d fd = %d\n", -n
,
1472 static void do_io(struct io_thread_req
*req
)
1476 int n
, nsectors
, start
, end
, bit
;
1479 if (req
->op
== UBD_FLUSH
) {
1480 /* fds[0] is always either the rw image or our cow file */
1481 n
= os_sync_file(req
->fds
[0]);
1483 printk("do_io - sync failed err = %d "
1484 "fd = %d\n", -n
, req
->fds
[0]);
1490 nsectors
= req
->length
/ req
->sectorsize
;
1493 bit
= ubd_test_bit(start
, (unsigned char *) &req
->sector_mask
);
1495 while((end
< nsectors
) &&
1496 (ubd_test_bit(end
, (unsigned char *)
1497 &req
->sector_mask
) == bit
))
1500 off
= req
->offset
+ req
->offsets
[bit
] +
1501 start
* req
->sectorsize
;
1502 len
= (end
- start
) * req
->sectorsize
;
1503 buf
= &req
->buffer
[start
* req
->sectorsize
];
1505 if(req
->op
== UBD_READ
){
1510 n
= os_pread_file(req
->fds
[bit
], buf
, len
, off
);
1512 printk("do_io - read failed, err = %d "
1513 "fd = %d\n", -n
, req
->fds
[bit
]);
1517 } while((n
< len
) && (n
!= 0));
1518 if (n
< len
) memset(&buf
[n
], 0, len
- n
);
1520 n
= os_pwrite_file(req
->fds
[bit
], buf
, len
, off
);
1522 printk("do_io - write failed err = %d "
1523 "fd = %d\n", -n
, req
->fds
[bit
]);
1530 } while(start
< nsectors
);
1532 req
->error
= update_bitmap(req
);
1535 /* Changed in start_io_thread, which is serialized by being called only
1536 * from ubd_init, which is an initcall.
1540 /* Only changed by the io thread. XXX: currently unused. */
1541 static int io_count
= 0;
1543 int io_thread(void *arg
)
1545 int n
, count
, written
, res
;
1547 os_fix_helper_signals();
1550 n
= bulk_req_safe_read(
1562 printk("io_thread - read failed, fd = %d, "
1565 kernel_fd
, -n
, io_remainder_size
);
1569 for (count
= 0; count
< n
/sizeof(struct io_thread_req
*); count
++) {
1571 do_io((*io_req_buffer
)[count
]);
1577 res
= os_write_file(kernel_fd
, ((char *) io_req_buffer
) + written
, n
);
1581 if (res
!= -EAGAIN
) {
1582 printk("io_thread - write failed, fd = %d, "
1583 "err = %d\n", kernel_fd
, -n
);
1589 } while (written
< n
);