11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) 31da177e4SLinus Torvalds * Licensed under the GPL 41da177e4SLinus Torvalds */ 51da177e4SLinus Torvalds 61da177e4SLinus Torvalds /* 2001-09-28...2002-04-17 71da177e4SLinus Torvalds * Partition stuff by James_McMechan@hotmail.com 81da177e4SLinus Torvalds * old style ubd by setting UBD_SHIFT to 0 91da177e4SLinus Torvalds * 2002-09-27...2002-10-18 massive tinkering for 2.5 101da177e4SLinus Torvalds * partitions have changed in 2.5 111da177e4SLinus Torvalds * 2003-01-29 more tinkering for 2.5.59-1 121da177e4SLinus Torvalds * This should now address the sysfs problems and has 131da177e4SLinus Torvalds * the symlink for devfs to allow for booting with 141da177e4SLinus Torvalds * the common /dev/ubd/discX/... names rather than 151da177e4SLinus Torvalds * only /dev/ubdN/discN this version also has lots of 161da177e4SLinus Torvalds * clean ups preparing for ubd-many. 171da177e4SLinus Torvalds * James McMechan 181da177e4SLinus Torvalds */ 191da177e4SLinus Torvalds 201da177e4SLinus Torvalds #define MAJOR_NR UBD_MAJOR 211da177e4SLinus Torvalds #define UBD_SHIFT 4 221da177e4SLinus Torvalds 231da177e4SLinus Torvalds #include "linux/module.h" 241da177e4SLinus Torvalds #include "linux/blkdev.h" 251da177e4SLinus Torvalds #include "linux/hdreg.h" 261da177e4SLinus Torvalds #include "linux/init.h" 271da177e4SLinus Torvalds #include "linux/cdrom.h" 281da177e4SLinus Torvalds #include "linux/proc_fs.h" 291da177e4SLinus Torvalds #include "linux/ctype.h" 301da177e4SLinus Torvalds #include "linux/capability.h" 311da177e4SLinus Torvalds #include "linux/mm.h" 321da177e4SLinus Torvalds #include "linux/vmalloc.h" 331da177e4SLinus Torvalds #include "linux/blkpg.h" 341da177e4SLinus Torvalds #include "linux/genhd.h" 351da177e4SLinus Torvalds #include "linux/spinlock.h" 36d052d1beSRussell King #include "linux/platform_device.h" 371da177e4SLinus Torvalds #include "asm/segment.h" 381da177e4SLinus Torvalds #include "asm/uaccess.h" 391da177e4SLinus Torvalds #include "asm/irq.h" 401da177e4SLinus Torvalds #include "asm/types.h" 411da177e4SLinus Torvalds #include "asm/tlbflush.h" 421da177e4SLinus Torvalds #include "user_util.h" 431da177e4SLinus Torvalds #include "mem_user.h" 441da177e4SLinus Torvalds #include "kern_util.h" 451da177e4SLinus Torvalds #include "kern.h" 461da177e4SLinus Torvalds #include "mconsole_kern.h" 471da177e4SLinus Torvalds #include "init.h" 481da177e4SLinus Torvalds #include "irq_user.h" 491da177e4SLinus Torvalds #include "irq_kern.h" 501da177e4SLinus Torvalds #include "ubd_user.h" 511da177e4SLinus Torvalds #include "os.h" 521da177e4SLinus Torvalds #include "mem.h" 531da177e4SLinus Torvalds #include "mem_kern.h" 541da177e4SLinus Torvalds #include "cow.h" 551da177e4SLinus Torvalds 567b9014c1SJeff Dike enum ubd_req { UBD_READ, UBD_WRITE }; 571da177e4SLinus Torvalds 581da177e4SLinus Torvalds struct io_thread_req { 5991acb21fSJeff Dike enum ubd_req op; 601da177e4SLinus Torvalds int fds[2]; 611da177e4SLinus Torvalds unsigned long offsets[2]; 621da177e4SLinus Torvalds unsigned long long offset; 631da177e4SLinus Torvalds unsigned long length; 641da177e4SLinus Torvalds char *buffer; 651da177e4SLinus Torvalds int sectorsize; 6691acb21fSJeff Dike unsigned long sector_mask; 6791acb21fSJeff Dike unsigned long long cow_offset; 6891acb21fSJeff Dike unsigned long bitmap_words[2]; 691da177e4SLinus Torvalds int error; 701da177e4SLinus Torvalds }; 711da177e4SLinus Torvalds 726c29256cSJeff Dike extern int open_ubd_file(char *file, struct openflags *openflags, int shared, 731da177e4SLinus Torvalds char **backing_file_out, int *bitmap_offset_out, 741da177e4SLinus Torvalds unsigned long *bitmap_len_out, int *data_offset_out, 751da177e4SLinus Torvalds int *create_cow_out); 761da177e4SLinus Torvalds extern int create_cow_file(char *cow_file, char *backing_file, 771da177e4SLinus Torvalds struct openflags flags, int sectorsize, 781da177e4SLinus Torvalds int alignment, int *bitmap_offset_out, 791da177e4SLinus Torvalds unsigned long *bitmap_len_out, 801da177e4SLinus Torvalds int *data_offset_out); 811da177e4SLinus Torvalds extern int read_cow_bitmap(int fd, void *buf, int offset, int len); 8291acb21fSJeff Dike extern void do_io(struct io_thread_req *req); 831da177e4SLinus Torvalds 8491acb21fSJeff Dike static inline int ubd_test_bit(__u64 bit, unsigned char *data) 851da177e4SLinus Torvalds { 861da177e4SLinus Torvalds __u64 n; 871da177e4SLinus Torvalds int bits, off; 881da177e4SLinus Torvalds 8991acb21fSJeff Dike bits = sizeof(data[0]) * 8; 901da177e4SLinus Torvalds n = bit / bits; 911da177e4SLinus Torvalds off = bit % bits; 9291acb21fSJeff Dike return((data[n] & (1 << off)) != 0); 931da177e4SLinus Torvalds } 941da177e4SLinus Torvalds 9591acb21fSJeff Dike static inline void ubd_set_bit(__u64 bit, unsigned char *data) 961da177e4SLinus Torvalds { 971da177e4SLinus Torvalds __u64 n; 981da177e4SLinus Torvalds int bits, off; 991da177e4SLinus Torvalds 10091acb21fSJeff Dike bits = sizeof(data[0]) * 8; 1011da177e4SLinus Torvalds n = bit / bits; 1021da177e4SLinus Torvalds off = bit % bits; 10391acb21fSJeff Dike data[n] |= (1 << off); 1041da177e4SLinus Torvalds } 1051da177e4SLinus Torvalds /*End stuff from ubd_user.h*/ 1061da177e4SLinus Torvalds 1071da177e4SLinus Torvalds #define DRIVER_NAME "uml-blkdev" 1081da177e4SLinus Torvalds 10933f775eeSPaolo 'Blaisorblade' Giarrusso /* Can be taken in interrupt context, and is passed to the block layer to lock 11033f775eeSPaolo 'Blaisorblade' Giarrusso * the request queue. Kernel side code knows that. */ 1111da177e4SLinus Torvalds static DEFINE_SPINLOCK(ubd_io_lock); 112d7fb2c38SPaolo 'Blaisorblade' Giarrusso 113d7fb2c38SPaolo 'Blaisorblade' Giarrusso static DEFINE_MUTEX(ubd_lock); 1141da177e4SLinus Torvalds 1152fe30a34SPaolo 'Blaisorblade' Giarrusso /* XXX - this made sense in 2.4 days, now it's only used as a boolean, and 1162fe30a34SPaolo 'Blaisorblade' Giarrusso * probably it doesn't make sense even for that. */ 1172fe30a34SPaolo 'Blaisorblade' Giarrusso static int do_ubd; 11891acb21fSJeff Dike 1191da177e4SLinus Torvalds static int ubd_open(struct inode * inode, struct file * filp); 1201da177e4SLinus Torvalds static int ubd_release(struct inode * inode, struct file * file); 1211da177e4SLinus Torvalds static int ubd_ioctl(struct inode * inode, struct file * file, 1221da177e4SLinus Torvalds unsigned int cmd, unsigned long arg); 123a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); 1241da177e4SLinus Torvalds 12597d88ac8SPaolo 'Blaisorblade' Giarrusso #define MAX_DEV (16) 1261da177e4SLinus Torvalds 1271da177e4SLinus Torvalds static struct block_device_operations ubd_blops = { 1281da177e4SLinus Torvalds .owner = THIS_MODULE, 1291da177e4SLinus Torvalds .open = ubd_open, 1301da177e4SLinus Torvalds .release = ubd_release, 1311da177e4SLinus Torvalds .ioctl = ubd_ioctl, 132a885c8c4SChristoph Hellwig .getgeo = ubd_getgeo, 1331da177e4SLinus Torvalds }; 1341da177e4SLinus Torvalds 1351da177e4SLinus Torvalds /* Protected by the queue_lock */ 1361da177e4SLinus Torvalds static request_queue_t *ubd_queue; 1371da177e4SLinus Torvalds 1381da177e4SLinus Torvalds /* Protected by ubd_lock */ 1391da177e4SLinus Torvalds static int fake_major = MAJOR_NR; 1401da177e4SLinus Torvalds 1411da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1421da177e4SLinus Torvalds static struct gendisk *fake_gendisk[MAX_DEV]; 1431da177e4SLinus Torvalds 1441da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1451da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1461da177e4SLinus Torvalds .cl = 1 }) 1471da177e4SLinus Torvalds #else 1481da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1491da177e4SLinus Torvalds .cl = 1 }) 1501da177e4SLinus Torvalds #endif 1511da177e4SLinus Torvalds 1521da177e4SLinus Torvalds /* Not protected - changed only in ubd_setup_common and then only to 1531da177e4SLinus Torvalds * to enable O_SYNC. 1541da177e4SLinus Torvalds */ 1551da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1561da177e4SLinus Torvalds 1571da177e4SLinus Torvalds struct cow { 1582a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file name */ 1591da177e4SLinus Torvalds char *file; 1602a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file fd */ 1611da177e4SLinus Torvalds int fd; 1621da177e4SLinus Torvalds unsigned long *bitmap; 1631da177e4SLinus Torvalds unsigned long bitmap_len; 1641da177e4SLinus Torvalds int bitmap_offset; 1651da177e4SLinus Torvalds int data_offset; 1661da177e4SLinus Torvalds }; 1671da177e4SLinus Torvalds 1681da177e4SLinus Torvalds struct ubd { 1692a9d32f6SPaolo 'Blaisorblade' Giarrusso /* name (and fd, below) of the file opened for writing, either the 1702a9d32f6SPaolo 'Blaisorblade' Giarrusso * backing or the cow file. */ 1711da177e4SLinus Torvalds char *file; 1721da177e4SLinus Torvalds int count; 1731da177e4SLinus Torvalds int fd; 1741da177e4SLinus Torvalds __u64 size; 1751da177e4SLinus Torvalds struct openflags boot_openflags; 1761da177e4SLinus Torvalds struct openflags openflags; 17784e945e3SPaolo 'Blaisorblade' Giarrusso unsigned shared:1; 17884e945e3SPaolo 'Blaisorblade' Giarrusso unsigned no_cow:1; 1791da177e4SLinus Torvalds struct cow cow; 1801da177e4SLinus Torvalds struct platform_device pdev; 1811da177e4SLinus Torvalds }; 1821da177e4SLinus Torvalds 1831da177e4SLinus Torvalds #define DEFAULT_COW { \ 1841da177e4SLinus Torvalds .file = NULL, \ 1851da177e4SLinus Torvalds .fd = -1, \ 1861da177e4SLinus Torvalds .bitmap = NULL, \ 1871da177e4SLinus Torvalds .bitmap_offset = 0, \ 1881da177e4SLinus Torvalds .data_offset = 0, \ 1891da177e4SLinus Torvalds } 1901da177e4SLinus Torvalds 1911da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1921da177e4SLinus Torvalds .file = NULL, \ 1931da177e4SLinus Torvalds .count = 0, \ 1941da177e4SLinus Torvalds .fd = -1, \ 1951da177e4SLinus Torvalds .size = -1, \ 1961da177e4SLinus Torvalds .boot_openflags = OPEN_FLAGS, \ 1971da177e4SLinus Torvalds .openflags = OPEN_FLAGS, \ 1981da177e4SLinus Torvalds .no_cow = 0, \ 1996c29256cSJeff Dike .shared = 0, \ 2001da177e4SLinus Torvalds .cow = DEFAULT_COW, \ 2011da177e4SLinus Torvalds } 2021da177e4SLinus Torvalds 2037d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd ubd_devs[MAX_DEV] = { [ 0 ... MAX_DEV - 1 ] = DEFAULT_UBD }; 2041da177e4SLinus Torvalds 2051da177e4SLinus Torvalds static int ubd0_init(void) 2061da177e4SLinus Torvalds { 2077d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 2081da177e4SLinus Torvalds 2097d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 2107d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 2111da177e4SLinus Torvalds return(0); 2121da177e4SLinus Torvalds } 2131da177e4SLinus Torvalds 2141da177e4SLinus Torvalds __initcall(ubd0_init); 2151da177e4SLinus Torvalds 2161da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 2171da177e4SLinus Torvalds static int fake_ide = 0; 2181da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 2191da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 2201da177e4SLinus Torvalds 2211da177e4SLinus Torvalds static void make_proc_ide(void) 2221da177e4SLinus Torvalds { 2231da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 2241da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 2251da177e4SLinus Torvalds } 2261da177e4SLinus Torvalds 2271da177e4SLinus Torvalds static int proc_ide_read_media(char *page, char **start, off_t off, int count, 2281da177e4SLinus Torvalds int *eof, void *data) 2291da177e4SLinus Torvalds { 2301da177e4SLinus Torvalds int len; 2311da177e4SLinus Torvalds 2321da177e4SLinus Torvalds strcpy(page, "disk\n"); 2331da177e4SLinus Torvalds len = strlen("disk\n"); 2341da177e4SLinus Torvalds len -= off; 2351da177e4SLinus Torvalds if (len < count){ 2361da177e4SLinus Torvalds *eof = 1; 2371da177e4SLinus Torvalds if (len <= 0) return 0; 2381da177e4SLinus Torvalds } 2391da177e4SLinus Torvalds else len = count; 2401da177e4SLinus Torvalds *start = page + off; 2411da177e4SLinus Torvalds return len; 2421da177e4SLinus Torvalds } 2431da177e4SLinus Torvalds 2441da177e4SLinus Torvalds static void make_ide_entries(char *dev_name) 2451da177e4SLinus Torvalds { 2461da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2471da177e4SLinus Torvalds char name[64]; 2481da177e4SLinus Torvalds 2491da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2501da177e4SLinus Torvalds 2511da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2521da177e4SLinus Torvalds if(!dir) return; 2531da177e4SLinus Torvalds 2541da177e4SLinus Torvalds ent = create_proc_entry("media", S_IFREG|S_IRUGO, dir); 2551da177e4SLinus Torvalds if(!ent) return; 2561da177e4SLinus Torvalds ent->nlink = 1; 2571da177e4SLinus Torvalds ent->data = NULL; 2581da177e4SLinus Torvalds ent->read_proc = proc_ide_read_media; 2591da177e4SLinus Torvalds ent->write_proc = NULL; 2601da177e4SLinus Torvalds sprintf(name,"ide0/%s", dev_name); 2611da177e4SLinus Torvalds proc_symlink(dev_name, proc_ide_root, name); 2621da177e4SLinus Torvalds } 2631da177e4SLinus Torvalds 2641da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2651da177e4SLinus Torvalds { 2661da177e4SLinus Torvalds fake_ide = 1; 2671da177e4SLinus Torvalds return(1); 2681da177e4SLinus Torvalds } 2691da177e4SLinus Torvalds 2701da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2711da177e4SLinus Torvalds 2721da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2731da177e4SLinus Torvalds "fake_ide\n" 2741da177e4SLinus Torvalds " Create ide0 entries that map onto ubd devices.\n\n" 2751da177e4SLinus Torvalds ); 2761da177e4SLinus Torvalds 2771da177e4SLinus Torvalds static int parse_unit(char **ptr) 2781da177e4SLinus Torvalds { 2791da177e4SLinus Torvalds char *str = *ptr, *end; 2801da177e4SLinus Torvalds int n = -1; 2811da177e4SLinus Torvalds 2821da177e4SLinus Torvalds if(isdigit(*str)) { 2831da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2841da177e4SLinus Torvalds if(end == str) 2851da177e4SLinus Torvalds return(-1); 2861da177e4SLinus Torvalds *ptr = end; 2871da177e4SLinus Torvalds } 28897d88ac8SPaolo 'Blaisorblade' Giarrusso else if (('a' <= *str) && (*str <= 'z')) { 2891da177e4SLinus Torvalds n = *str - 'a'; 2901da177e4SLinus Torvalds str++; 2911da177e4SLinus Torvalds *ptr = str; 2921da177e4SLinus Torvalds } 2931da177e4SLinus Torvalds return(n); 2941da177e4SLinus Torvalds } 2951da177e4SLinus Torvalds 2961da177e4SLinus Torvalds static int ubd_setup_common(char *str, int *index_out) 2971da177e4SLinus Torvalds { 2987d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 2991da177e4SLinus Torvalds struct openflags flags = global_openflags; 3001da177e4SLinus Torvalds char *backing_file; 3011da177e4SLinus Torvalds int n, err, i; 3021da177e4SLinus Torvalds 3031da177e4SLinus Torvalds if(index_out) *index_out = -1; 3041da177e4SLinus Torvalds n = *str; 3051da177e4SLinus Torvalds if(n == '='){ 3061da177e4SLinus Torvalds char *end; 3071da177e4SLinus Torvalds int major; 3081da177e4SLinus Torvalds 3091da177e4SLinus Torvalds str++; 3101da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 3111da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 3121da177e4SLinus Torvalds return(0); 3131da177e4SLinus Torvalds } 3141da177e4SLinus Torvalds major = simple_strtoul(str, &end, 0); 3151da177e4SLinus Torvalds if((*end != '\0') || (end == str)){ 3161da177e4SLinus Torvalds printk(KERN_ERR 3171da177e4SLinus Torvalds "ubd_setup : didn't parse major number\n"); 3181da177e4SLinus Torvalds return(1); 3191da177e4SLinus Torvalds } 3201da177e4SLinus Torvalds 3211da177e4SLinus Torvalds err = 1; 322d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 3231da177e4SLinus Torvalds if(fake_major != MAJOR_NR){ 3241da177e4SLinus Torvalds printk(KERN_ERR "Can't assign a fake major twice\n"); 3251da177e4SLinus Torvalds goto out1; 3261da177e4SLinus Torvalds } 3271da177e4SLinus Torvalds 3281da177e4SLinus Torvalds fake_major = major; 3291da177e4SLinus Torvalds 3301da177e4SLinus Torvalds printk(KERN_INFO "Setting extra ubd major number to %d\n", 3311da177e4SLinus Torvalds major); 3321da177e4SLinus Torvalds err = 0; 3331da177e4SLinus Torvalds out1: 334d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 3351da177e4SLinus Torvalds return(err); 3361da177e4SLinus Torvalds } 3371da177e4SLinus Torvalds 3381da177e4SLinus Torvalds n = parse_unit(&str); 3391da177e4SLinus Torvalds if(n < 0){ 3401da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : couldn't parse unit number " 3411da177e4SLinus Torvalds "'%s'\n", str); 3421da177e4SLinus Torvalds return(1); 3431da177e4SLinus Torvalds } 3441da177e4SLinus Torvalds if(n >= MAX_DEV){ 3451da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : index %d out of range " 3461da177e4SLinus Torvalds "(%d devices, from 0 to %d)\n", n, MAX_DEV, MAX_DEV - 1); 3471da177e4SLinus Torvalds return(1); 3481da177e4SLinus Torvalds } 3491da177e4SLinus Torvalds 3501da177e4SLinus Torvalds err = 1; 351d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 3521da177e4SLinus Torvalds 3537d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 3547d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file != NULL){ 3551da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : device already configured\n"); 3561da177e4SLinus Torvalds goto out; 3571da177e4SLinus Torvalds } 3581da177e4SLinus Torvalds 3591da177e4SLinus Torvalds if (index_out) 3601da177e4SLinus Torvalds *index_out = n; 3611da177e4SLinus Torvalds 3626c29256cSJeff Dike for (i = 0; i < sizeof("rscd="); i++) { 3631da177e4SLinus Torvalds switch (*str) { 3641da177e4SLinus Torvalds case 'r': 3651da177e4SLinus Torvalds flags.w = 0; 3661da177e4SLinus Torvalds break; 3671da177e4SLinus Torvalds case 's': 3681da177e4SLinus Torvalds flags.s = 1; 3691da177e4SLinus Torvalds break; 3701da177e4SLinus Torvalds case 'd': 3717d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->no_cow = 1; 3721da177e4SLinus Torvalds break; 3736c29256cSJeff Dike case 'c': 3747d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->shared = 1; 3756c29256cSJeff Dike break; 3761da177e4SLinus Torvalds case '=': 3771da177e4SLinus Torvalds str++; 3781da177e4SLinus Torvalds goto break_loop; 3791da177e4SLinus Torvalds default: 3806c29256cSJeff Dike printk(KERN_ERR "ubd_setup : Expected '=' or flag letter (r, s, c, or d)\n"); 3811da177e4SLinus Torvalds goto out; 3821da177e4SLinus Torvalds } 3831da177e4SLinus Torvalds str++; 3841da177e4SLinus Torvalds } 3851da177e4SLinus Torvalds 3861da177e4SLinus Torvalds if (*str == '=') 3871da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : Too many flags specified\n"); 3881da177e4SLinus Torvalds else 3891da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : Expected '='\n"); 3901da177e4SLinus Torvalds goto out; 3911da177e4SLinus Torvalds 3921da177e4SLinus Torvalds break_loop: 3931da177e4SLinus Torvalds err = 0; 3941da177e4SLinus Torvalds backing_file = strchr(str, ','); 3951da177e4SLinus Torvalds 3961da177e4SLinus Torvalds if (!backing_file) { 3971da177e4SLinus Torvalds backing_file = strchr(str, ':'); 3981da177e4SLinus Torvalds } 3991da177e4SLinus Torvalds 4001da177e4SLinus Torvalds if(backing_file){ 4017d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->no_cow) 4021da177e4SLinus Torvalds printk(KERN_ERR "Can't specify both 'd' and a " 4031da177e4SLinus Torvalds "cow file\n"); 4041da177e4SLinus Torvalds else { 4051da177e4SLinus Torvalds *backing_file = '\0'; 4061da177e4SLinus Torvalds backing_file++; 4071da177e4SLinus Torvalds } 4081da177e4SLinus Torvalds } 4097d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->file = str; 4107d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.file = backing_file; 4117d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->boot_openflags = flags; 4121da177e4SLinus Torvalds out: 413d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 4141da177e4SLinus Torvalds return(err); 4151da177e4SLinus Torvalds } 4161da177e4SLinus Torvalds 4171da177e4SLinus Torvalds static int ubd_setup(char *str) 4181da177e4SLinus Torvalds { 4191da177e4SLinus Torvalds ubd_setup_common(str, NULL); 4201da177e4SLinus Torvalds return(1); 4211da177e4SLinus Torvalds } 4221da177e4SLinus Torvalds 4231da177e4SLinus Torvalds __setup("ubd", ubd_setup); 4241da177e4SLinus Torvalds __uml_help(ubd_setup, 4251da177e4SLinus Torvalds "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" 4261da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 4271da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 4281da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 4291da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 4301da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 4311da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 4321da177e4SLinus Torvalds " When using only one filename, UML will detect whether to thread it like\n" 4331da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 4341da177e4SLinus Torvalds " flag:\n" 4351da177e4SLinus Torvalds " ubd0d=BackingFile\n" 4361da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 4371da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 4381da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 4391da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 4401da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 4411da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 4421da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 4431da177e4SLinus Torvalds " an 's' will cause data to be written to disk on the host immediately.\n\n" 4441da177e4SLinus Torvalds ); 4451da177e4SLinus Torvalds 4461da177e4SLinus Torvalds static int udb_setup(char *str) 4471da177e4SLinus Torvalds { 4481da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 4491da177e4SLinus Torvalds "udb TYPO\n", str); 4501da177e4SLinus Torvalds return(1); 4511da177e4SLinus Torvalds } 4521da177e4SLinus Torvalds 4531da177e4SLinus Torvalds __setup("udb", udb_setup); 4541da177e4SLinus Torvalds __uml_help(udb_setup, 4551da177e4SLinus Torvalds "udb\n" 4560894e27eSJeff Dike " This option is here solely to catch ubd -> udb typos, which can be\n" 4570894e27eSJeff Dike " to impossible to catch visually unless you specifically look for\n" 4580894e27eSJeff Dike " them. The only result of any option starting with 'udb' is an error\n" 4591da177e4SLinus Torvalds " in the boot output.\n\n" 4601da177e4SLinus Torvalds ); 4611da177e4SLinus Torvalds 4621da177e4SLinus Torvalds static int fakehd_set = 0; 4631da177e4SLinus Torvalds static int fakehd(char *str) 4641da177e4SLinus Torvalds { 4651da177e4SLinus Torvalds printk(KERN_INFO "fakehd : Changing ubd name to \"hd\".\n"); 4661da177e4SLinus Torvalds fakehd_set = 1; 4671da177e4SLinus Torvalds return 1; 4681da177e4SLinus Torvalds } 4691da177e4SLinus Torvalds 4701da177e4SLinus Torvalds __setup("fakehd", fakehd); 4711da177e4SLinus Torvalds __uml_help(fakehd, 4721da177e4SLinus Torvalds "fakehd\n" 4731da177e4SLinus Torvalds " Change the ubd device name to \"hd\".\n\n" 4741da177e4SLinus Torvalds ); 4751da177e4SLinus Torvalds 4761da177e4SLinus Torvalds static void do_ubd_request(request_queue_t * q); 47791acb21fSJeff Dike 47891acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 47991acb21fSJeff Dike int thread_fd = -1; 4801da177e4SLinus Torvalds 4811da177e4SLinus Torvalds /* Changed by ubd_handler, which is serialized because interrupts only 4821da177e4SLinus Torvalds * happen on CPU 0. 4831da177e4SLinus Torvalds */ 4841da177e4SLinus Torvalds int intr_count = 0; 4851da177e4SLinus Torvalds 4861da177e4SLinus Torvalds /* call ubd_finish if you need to serialize */ 48791acb21fSJeff Dike static void __ubd_finish(struct request *req, int error) 4881da177e4SLinus Torvalds { 48991acb21fSJeff Dike int nsect; 49091acb21fSJeff Dike 49191acb21fSJeff Dike if(error){ 49291acb21fSJeff Dike end_request(req, 0); 4931da177e4SLinus Torvalds return; 4941da177e4SLinus Torvalds } 49591acb21fSJeff Dike nsect = req->current_nr_sectors; 49691acb21fSJeff Dike req->sector += nsect; 49791acb21fSJeff Dike req->buffer += nsect << 9; 49891acb21fSJeff Dike req->errors = 0; 49991acb21fSJeff Dike req->nr_sectors -= nsect; 50091acb21fSJeff Dike req->current_nr_sectors = 0; 50191acb21fSJeff Dike end_request(req, 1); 5021da177e4SLinus Torvalds } 5031da177e4SLinus Torvalds 50433f775eeSPaolo 'Blaisorblade' Giarrusso /* Callable only from interrupt context - otherwise you need to do 50533f775eeSPaolo 'Blaisorblade' Giarrusso * spin_lock_irq()/spin_lock_irqsave() */ 50691acb21fSJeff Dike static inline void ubd_finish(struct request *req, int error) 50709ace81cSJeff Dike { 50809ace81cSJeff Dike spin_lock(&ubd_io_lock); 50991acb21fSJeff Dike __ubd_finish(req, error); 51009ace81cSJeff Dike spin_unlock(&ubd_io_lock); 51109ace81cSJeff Dike } 51209ace81cSJeff Dike 5132fe30a34SPaolo 'Blaisorblade' Giarrusso /* XXX - move this inside ubd_intr. */ 51433f775eeSPaolo 'Blaisorblade' Giarrusso /* Called without ubd_io_lock held, and only in interrupt context. */ 51591acb21fSJeff Dike static void ubd_handler(void) 51691acb21fSJeff Dike { 51791acb21fSJeff Dike struct io_thread_req req; 51891acb21fSJeff Dike struct request *rq = elv_next_request(ubd_queue); 51991acb21fSJeff Dike int n; 52009ace81cSJeff Dike 5212fe30a34SPaolo 'Blaisorblade' Giarrusso do_ubd = 0; 52291acb21fSJeff Dike intr_count++; 52391acb21fSJeff Dike n = os_read_file(thread_fd, &req, sizeof(req)); 52491acb21fSJeff Dike if(n != sizeof(req)){ 52591acb21fSJeff Dike printk(KERN_ERR "Pid %d - spurious interrupt in ubd_handler, " 52691acb21fSJeff Dike "err = %d\n", os_getpid(), -n); 52791acb21fSJeff Dike spin_lock(&ubd_io_lock); 52891acb21fSJeff Dike end_request(rq, 0); 52991acb21fSJeff Dike spin_unlock(&ubd_io_lock); 53091acb21fSJeff Dike return; 53191acb21fSJeff Dike } 53209ace81cSJeff Dike 53391acb21fSJeff Dike ubd_finish(rq, req.error); 53491acb21fSJeff Dike reactivate_fd(thread_fd, UBD_IRQ); 53533f775eeSPaolo 'Blaisorblade' Giarrusso spin_lock(&ubd_io_lock); 53691acb21fSJeff Dike do_ubd_request(ubd_queue); 53733f775eeSPaolo 'Blaisorblade' Giarrusso spin_unlock(&ubd_io_lock); 53891acb21fSJeff Dike } 53909ace81cSJeff Dike 5407bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 5411da177e4SLinus Torvalds { 54291acb21fSJeff Dike ubd_handler(); 5431da177e4SLinus Torvalds return(IRQ_HANDLED); 5441da177e4SLinus Torvalds } 5451da177e4SLinus Torvalds 54691acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 54791acb21fSJeff Dike static int io_pid = -1; 54891acb21fSJeff Dike 54991acb21fSJeff Dike void kill_io_thread(void) 55091acb21fSJeff Dike { 55191acb21fSJeff Dike if(io_pid != -1) 55291acb21fSJeff Dike os_kill_process(io_pid, 1); 55391acb21fSJeff Dike } 55491acb21fSJeff Dike 55591acb21fSJeff Dike __uml_exitcall(kill_io_thread); 55691acb21fSJeff Dike 5577d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5581da177e4SLinus Torvalds { 5591da177e4SLinus Torvalds char *file; 5601da177e4SLinus Torvalds 5617d314e34SPaolo 'Blaisorblade' Giarrusso file = ubd_dev->cow.file ? ubd_dev->cow.file : ubd_dev->file; 5621da177e4SLinus Torvalds return(os_file_size(file, size_out)); 5631da177e4SLinus Torvalds } 5641da177e4SLinus Torvalds 5655f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 5661da177e4SLinus Torvalds { 5677d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 5687d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 5691da177e4SLinus Torvalds return; 5701da177e4SLinus Torvalds 5717d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 5727d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 5737d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 5741da177e4SLinus Torvalds } 5751da177e4SLinus Torvalds 5767d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 5771da177e4SLinus Torvalds { 5781da177e4SLinus Torvalds struct openflags flags; 5791da177e4SLinus Torvalds char **back_ptr; 5801da177e4SLinus Torvalds int err, create_cow, *create_ptr; 5810bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 5821da177e4SLinus Torvalds 5837d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 5841da177e4SLinus Torvalds create_cow = 0; 5857d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 5867d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 5870bf16bffSPaolo 'Blaisorblade' Giarrusso 5880bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 5897d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 5907d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 5916c29256cSJeff Dike create_ptr); 5921da177e4SLinus Torvalds 5930bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 5940bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 5957d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags, 1 << 9, PAGE_SIZE, 5967d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 5977d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 5987d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 5990bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 6001da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 6017d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 6021da177e4SLinus Torvalds } 6031da177e4SLinus Torvalds } 6041da177e4SLinus Torvalds 6050bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 6067d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 6070bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 6080bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 6091da177e4SLinus Torvalds } 6100bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 6111da177e4SLinus Torvalds 6127d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 6131da177e4SLinus Torvalds err = -ENOMEM; 6147d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = (void *) vmalloc(ubd_dev->cow.bitmap_len); 6157d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 6161da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 6171da177e4SLinus Torvalds goto error; 6181da177e4SLinus Torvalds } 6191da177e4SLinus Torvalds flush_tlb_kernel_vm(); 6201da177e4SLinus Torvalds 6217d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 6227d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 6237d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 6241da177e4SLinus Torvalds if(err < 0) 6251da177e4SLinus Torvalds goto error; 6261da177e4SLinus Torvalds 6277d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 6281da177e4SLinus Torvalds flags.w = 0; 6297d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 6306c29256cSJeff Dike NULL, NULL, NULL, NULL); 6311da177e4SLinus Torvalds if(err < 0) goto error; 6327d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 6331da177e4SLinus Torvalds } 6341da177e4SLinus Torvalds return(0); 6351da177e4SLinus Torvalds error: 6367d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 6371da177e4SLinus Torvalds return(err); 6381da177e4SLinus Torvalds } 6391da177e4SLinus Torvalds 6405f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 6411da177e4SLinus Torvalds struct gendisk **disk_out) 6421da177e4SLinus Torvalds 6431da177e4SLinus Torvalds { 6441da177e4SLinus Torvalds struct gendisk *disk; 6451da177e4SLinus Torvalds 6461da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 6471da177e4SLinus Torvalds if(disk == NULL) 6481da177e4SLinus Torvalds return(-ENOMEM); 6491da177e4SLinus Torvalds 6501da177e4SLinus Torvalds disk->major = major; 6511da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 6521da177e4SLinus Torvalds disk->fops = &ubd_blops; 6531da177e4SLinus Torvalds set_capacity(disk, size / 512); 654ce7b0f46SGreg Kroah-Hartman if(major == MAJOR_NR) 6551da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 656ce7b0f46SGreg Kroah-Hartman else 6571da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 6581da177e4SLinus Torvalds 6591da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 6601da177e4SLinus Torvalds if (major == MAJOR_NR) { 6617d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 6627d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 6637d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 6647d314e34SPaolo 'Blaisorblade' Giarrusso disk->driverfs_dev = &ubd_devs[unit].pdev.dev; 6651da177e4SLinus Torvalds } 6661da177e4SLinus Torvalds 6677d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 6681da177e4SLinus Torvalds disk->queue = ubd_queue; 6691da177e4SLinus Torvalds add_disk(disk); 6701da177e4SLinus Torvalds 6711da177e4SLinus Torvalds *disk_out = disk; 6721da177e4SLinus Torvalds return 0; 6731da177e4SLinus Torvalds } 6741da177e4SLinus Torvalds 6751da177e4SLinus Torvalds #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) 6761da177e4SLinus Torvalds 6771da177e4SLinus Torvalds static int ubd_add(int n) 6781da177e4SLinus Torvalds { 6797d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 6801da177e4SLinus Torvalds int err; 6811da177e4SLinus Torvalds 682ec7cf783SJeff Dike err = -ENODEV; 6837d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 684ec7cf783SJeff Dike goto out; 6851da177e4SLinus Torvalds 6867d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 6871da177e4SLinus Torvalds if(err < 0) 68880c13749SJeff Dike goto out; 6891da177e4SLinus Torvalds 6907d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 6911da177e4SLinus Torvalds 6925f75a4f8SPaolo 'Blaisorblade' Giarrusso err = ubd_disk_register(MAJOR_NR, ubd_dev->size, n, &ubd_gendisk[n]); 6931da177e4SLinus Torvalds if(err) 69480c13749SJeff Dike goto out; 6951da177e4SLinus Torvalds 6961da177e4SLinus Torvalds if(fake_major != MAJOR_NR) 6975f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 6981da177e4SLinus Torvalds &fake_gendisk[n]); 6991da177e4SLinus Torvalds 7001da177e4SLinus Torvalds /* perhaps this should also be under the "if (fake_major)" above */ 7011da177e4SLinus Torvalds /* using the fake_disk->disk_name and also the fakehd_set name */ 7021da177e4SLinus Torvalds if (fake_ide) 7031da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 7041da177e4SLinus Torvalds 705ec7cf783SJeff Dike err = 0; 706ec7cf783SJeff Dike out: 707ec7cf783SJeff Dike return err; 7081da177e4SLinus Torvalds } 7091da177e4SLinus Torvalds 7101da177e4SLinus Torvalds static int ubd_config(char *str) 7111da177e4SLinus Torvalds { 712e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 7131da177e4SLinus Torvalds 714970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 7151da177e4SLinus Torvalds if (str == NULL) { 7161da177e4SLinus Torvalds printk(KERN_ERR "ubd_config failed to strdup string\n"); 717e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 1; 718e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 7191da177e4SLinus Torvalds } 720e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = ubd_setup_common(str, &n); 721e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) { 722e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = -1; 723e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 7241da177e4SLinus Torvalds } 725e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 726e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 727e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 728e7f6552fSPaolo 'Blaisorblade' Giarrusso } 7291da177e4SLinus Torvalds 730d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 731e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = ubd_add(n); 732e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 7337d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 734d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 7351da177e4SLinus Torvalds 736e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 737e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 738e7f6552fSPaolo 'Blaisorblade' Giarrusso 739e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 740e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 741e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 7421da177e4SLinus Torvalds } 7431da177e4SLinus Torvalds 7441da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 7451da177e4SLinus Torvalds { 7467d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 7471da177e4SLinus Torvalds int n, len = 0; 7481da177e4SLinus Torvalds 7491da177e4SLinus Torvalds n = parse_unit(&name); 7501da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 7511da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 7521da177e4SLinus Torvalds return(-1); 7531da177e4SLinus Torvalds } 7541da177e4SLinus Torvalds 7557d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 756d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 7571da177e4SLinus Torvalds 7587d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 7591da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 7601da177e4SLinus Torvalds goto out; 7611da177e4SLinus Torvalds } 7621da177e4SLinus Torvalds 7637d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 7641da177e4SLinus Torvalds 7657d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 7661da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 7677d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 7681da177e4SLinus Torvalds } 7691da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 7701da177e4SLinus Torvalds 7711da177e4SLinus Torvalds out: 772d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 7731da177e4SLinus Torvalds return(len); 7741da177e4SLinus Torvalds } 7751da177e4SLinus Torvalds 77629d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 77729d56cfeSJeff Dike { 77829d56cfeSJeff Dike int n; 77929d56cfeSJeff Dike 78029d56cfeSJeff Dike n = parse_unit(str); 78129d56cfeSJeff Dike *start_out = 0; 78229d56cfeSJeff Dike *end_out = MAX_DEV - 1; 78329d56cfeSJeff Dike return n; 78429d56cfeSJeff Dike } 78529d56cfeSJeff Dike 78629d56cfeSJeff Dike static int ubd_remove(int n) 7871da177e4SLinus Torvalds { 7887d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 78929d56cfeSJeff Dike int err = -ENODEV; 7901da177e4SLinus Torvalds 791d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 7921da177e4SLinus Torvalds 7931da177e4SLinus Torvalds if(ubd_gendisk[n] == NULL) 7941da177e4SLinus Torvalds goto out; 7951da177e4SLinus Torvalds 7967d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 79729d56cfeSJeff Dike 7987d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 79929d56cfeSJeff Dike goto out; 80029d56cfeSJeff Dike 80129d56cfeSJeff Dike /* you cannot remove a open disk */ 80229d56cfeSJeff Dike err = -EBUSY; 8037d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 80429d56cfeSJeff Dike goto out; 80529d56cfeSJeff Dike 8061da177e4SLinus Torvalds del_gendisk(ubd_gendisk[n]); 8071da177e4SLinus Torvalds put_disk(ubd_gendisk[n]); 8081da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 8091da177e4SLinus Torvalds 8101da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 8111da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 8121da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 8131da177e4SLinus Torvalds fake_gendisk[n] = NULL; 8141da177e4SLinus Torvalds } 8151da177e4SLinus Torvalds 8167d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_unregister(&ubd_dev->pdev); 8177d314e34SPaolo 'Blaisorblade' Giarrusso *ubd_dev = ((struct ubd) DEFAULT_UBD); 8181da177e4SLinus Torvalds err = 0; 8191da177e4SLinus Torvalds out: 820d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 82129d56cfeSJeff Dike return err; 8221da177e4SLinus Torvalds } 8231da177e4SLinus Torvalds 8241da177e4SLinus Torvalds static struct mc_device ubd_mc = { 8251da177e4SLinus Torvalds .name = "ubd", 8261da177e4SLinus Torvalds .config = ubd_config, 8271da177e4SLinus Torvalds .get_config = ubd_get_config, 82829d56cfeSJeff Dike .id = ubd_id, 8291da177e4SLinus Torvalds .remove = ubd_remove, 8301da177e4SLinus Torvalds }; 8311da177e4SLinus Torvalds 8321da177e4SLinus Torvalds static int ubd_mc_init(void) 8331da177e4SLinus Torvalds { 8341da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 8351da177e4SLinus Torvalds return 0; 8361da177e4SLinus Torvalds } 8371da177e4SLinus Torvalds 8381da177e4SLinus Torvalds __initcall(ubd_mc_init); 8391da177e4SLinus Torvalds 8403ae5eaecSRussell King static struct platform_driver ubd_driver = { 8413ae5eaecSRussell King .driver = { 8421da177e4SLinus Torvalds .name = DRIVER_NAME, 8433ae5eaecSRussell King }, 8441da177e4SLinus Torvalds }; 8451da177e4SLinus Torvalds 8461da177e4SLinus Torvalds int ubd_init(void) 8471da177e4SLinus Torvalds { 8481da177e4SLinus Torvalds int i; 8491da177e4SLinus Torvalds 8501da177e4SLinus Torvalds if (register_blkdev(MAJOR_NR, "ubd")) 8511da177e4SLinus Torvalds return -1; 8521da177e4SLinus Torvalds 8531da177e4SLinus Torvalds ubd_queue = blk_init_queue(do_ubd_request, &ubd_io_lock); 8541da177e4SLinus Torvalds if (!ubd_queue) { 8551da177e4SLinus Torvalds unregister_blkdev(MAJOR_NR, "ubd"); 8561da177e4SLinus Torvalds return -1; 8571da177e4SLinus Torvalds } 8581da177e4SLinus Torvalds 8591da177e4SLinus Torvalds if (fake_major != MAJOR_NR) { 8601da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 8611da177e4SLinus Torvalds 8621da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 8631da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 8641da177e4SLinus Torvalds return -1; 8651da177e4SLinus Torvalds } 8663ae5eaecSRussell King platform_driver_register(&ubd_driver); 8671da177e4SLinus Torvalds for (i = 0; i < MAX_DEV; i++) 8681da177e4SLinus Torvalds ubd_add(i); 8691da177e4SLinus Torvalds return 0; 8701da177e4SLinus Torvalds } 8711da177e4SLinus Torvalds 8721da177e4SLinus Torvalds late_initcall(ubd_init); 8731da177e4SLinus Torvalds 87491acb21fSJeff Dike int ubd_driver_init(void){ 87591acb21fSJeff Dike unsigned long stack; 87691acb21fSJeff Dike int err; 87791acb21fSJeff Dike 87891acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 87991acb21fSJeff Dike if(global_openflags.s){ 88091acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 88191acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 88291acb21fSJeff Dike * enough. So use anyway the io thread. */ 88391acb21fSJeff Dike } 88491acb21fSJeff Dike stack = alloc_stack(0, 0); 88591acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 88691acb21fSJeff Dike &thread_fd); 88791acb21fSJeff Dike if(io_pid < 0){ 88891acb21fSJeff Dike printk(KERN_ERR 88991acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 89091acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 89191acb21fSJeff Dike io_pid = -1; 89291acb21fSJeff Dike return(0); 89391acb21fSJeff Dike } 89491acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 8957d314e34SPaolo 'Blaisorblade' Giarrusso IRQF_DISABLED, "ubd", ubd_devs); 89691acb21fSJeff Dike if(err != 0) 89791acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 898f4c57a78SJeff Dike return 0; 89991acb21fSJeff Dike } 90091acb21fSJeff Dike 90191acb21fSJeff Dike device_initcall(ubd_driver_init); 90291acb21fSJeff Dike 9031da177e4SLinus Torvalds static int ubd_open(struct inode *inode, struct file *filp) 9041da177e4SLinus Torvalds { 9051da177e4SLinus Torvalds struct gendisk *disk = inode->i_bdev->bd_disk; 9067d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 9071da177e4SLinus Torvalds int err = 0; 9081da177e4SLinus Torvalds 9097d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 9107d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 9111da177e4SLinus Torvalds if(err){ 9121da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 9137d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 9141da177e4SLinus Torvalds goto out; 9151da177e4SLinus Torvalds } 9161da177e4SLinus Torvalds } 9177d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 9187d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 9192c49be99SPaolo 'Blaisorblade' Giarrusso 9202c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 9212c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 9227d314e34SPaolo 'Blaisorblade' Giarrusso /*if((filp->f_mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 9235f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 9241da177e4SLinus Torvalds err = -EROFS; 9252c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 9261da177e4SLinus Torvalds out: 9271da177e4SLinus Torvalds return(err); 9281da177e4SLinus Torvalds } 9291da177e4SLinus Torvalds 9301da177e4SLinus Torvalds static int ubd_release(struct inode * inode, struct file * file) 9311da177e4SLinus Torvalds { 9321da177e4SLinus Torvalds struct gendisk *disk = inode->i_bdev->bd_disk; 9337d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 9341da177e4SLinus Torvalds 9357d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 9365f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 9371da177e4SLinus Torvalds return(0); 9381da177e4SLinus Torvalds } 9391da177e4SLinus Torvalds 94091acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 94191acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 94291acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 94391acb21fSJeff Dike __u64 bitmap_len) 9441da177e4SLinus Torvalds { 94591acb21fSJeff Dike __u64 sector = io_offset >> 9; 94691acb21fSJeff Dike int i, update_bitmap = 0; 9471da177e4SLinus Torvalds 94891acb21fSJeff Dike for(i = 0; i < length >> 9; i++){ 94991acb21fSJeff Dike if(cow_mask != NULL) 95091acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 95191acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 95209ace81cSJeff Dike continue; 9531da177e4SLinus Torvalds 95491acb21fSJeff Dike update_bitmap = 1; 95591acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 9561da177e4SLinus Torvalds } 95791acb21fSJeff Dike 95891acb21fSJeff Dike if(!update_bitmap) 95991acb21fSJeff Dike return; 96091acb21fSJeff Dike 96191acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 96291acb21fSJeff Dike 96391acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 96491acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 96591acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 96691acb21fSJeff Dike * for the original diagnosis. 96791acb21fSJeff Dike */ 96891acb21fSJeff Dike if(*cow_offset == ((bitmap_len + sizeof(unsigned long) - 1) / 96991acb21fSJeff Dike sizeof(unsigned long) - 1)) 97091acb21fSJeff Dike (*cow_offset)--; 97191acb21fSJeff Dike 97291acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 97391acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 97491acb21fSJeff Dike 97591acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 97691acb21fSJeff Dike *cow_offset += bitmap_offset; 97791acb21fSJeff Dike } 97891acb21fSJeff Dike 97991acb21fSJeff Dike static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, 98091acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 98191acb21fSJeff Dike { 98291acb21fSJeff Dike __u64 sector = req->offset >> 9; 98391acb21fSJeff Dike int i; 98491acb21fSJeff Dike 98591acb21fSJeff Dike if(req->length > (sizeof(req->sector_mask) * 8) << 9) 98691acb21fSJeff Dike panic("Operation too long"); 98791acb21fSJeff Dike 98891acb21fSJeff Dike if(req->op == UBD_READ) { 98991acb21fSJeff Dike for(i = 0; i < req->length >> 9; i++){ 99091acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 99191acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 99291acb21fSJeff Dike &req->sector_mask); 99391acb21fSJeff Dike } 99491acb21fSJeff Dike } 99591acb21fSJeff Dike else cowify_bitmap(req->offset, req->length, &req->sector_mask, 99691acb21fSJeff Dike &req->cow_offset, bitmap, bitmap_offset, 99791acb21fSJeff Dike req->bitmap_words, bitmap_len); 9981da177e4SLinus Torvalds } 9991da177e4SLinus Torvalds 10001da177e4SLinus Torvalds /* Called with ubd_io_lock held */ 100191acb21fSJeff Dike static int prepare_request(struct request *req, struct io_thread_req *io_req) 10021da177e4SLinus Torvalds { 10031da177e4SLinus Torvalds struct gendisk *disk = req->rq_disk; 10047d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 100591acb21fSJeff Dike __u64 offset; 100691acb21fSJeff Dike int len; 100791acb21fSJeff Dike 10082c49be99SPaolo 'Blaisorblade' Giarrusso /* This should be impossible now */ 10097d314e34SPaolo 'Blaisorblade' Giarrusso if((rq_data_dir(req) == WRITE) && !ubd_dev->openflags.w){ 10101da177e4SLinus Torvalds printk("Write attempted on readonly ubd device %s\n", 10111da177e4SLinus Torvalds disk->disk_name); 101291acb21fSJeff Dike end_request(req, 0); 10131da177e4SLinus Torvalds return(1); 10141da177e4SLinus Torvalds } 10151da177e4SLinus Torvalds 101691acb21fSJeff Dike offset = ((__u64) req->sector) << 9; 101791acb21fSJeff Dike len = req->current_nr_sectors << 9; 101891acb21fSJeff Dike 10197d314e34SPaolo 'Blaisorblade' Giarrusso io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : ubd_dev->fd; 10207d314e34SPaolo 'Blaisorblade' Giarrusso io_req->fds[1] = ubd_dev->fd; 102191acb21fSJeff Dike io_req->cow_offset = -1; 10221da177e4SLinus Torvalds io_req->offset = offset; 10231da177e4SLinus Torvalds io_req->length = len; 10241da177e4SLinus Torvalds io_req->error = 0; 102591acb21fSJeff Dike io_req->sector_mask = 0; 102691acb21fSJeff Dike 102791acb21fSJeff Dike io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; 10281da177e4SLinus Torvalds io_req->offsets[0] = 0; 10297d314e34SPaolo 'Blaisorblade' Giarrusso io_req->offsets[1] = ubd_dev->cow.data_offset; 103091acb21fSJeff Dike io_req->buffer = req->buffer; 10311da177e4SLinus Torvalds io_req->sectorsize = 1 << 9; 10321da177e4SLinus Torvalds 10337d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL) 10347d314e34SPaolo 'Blaisorblade' Giarrusso cowify_req(io_req, ubd_dev->cow.bitmap, ubd_dev->cow.bitmap_offset, 10357d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 103691acb21fSJeff Dike 10371da177e4SLinus Torvalds return(0); 10381da177e4SLinus Torvalds } 10391da177e4SLinus Torvalds 10401da177e4SLinus Torvalds /* Called with ubd_io_lock held */ 10411da177e4SLinus Torvalds static void do_ubd_request(request_queue_t *q) 10421da177e4SLinus Torvalds { 10431da177e4SLinus Torvalds struct io_thread_req io_req; 10441da177e4SLinus Torvalds struct request *req; 104591acb21fSJeff Dike int err, n; 10461da177e4SLinus Torvalds 104791acb21fSJeff Dike if(thread_fd == -1){ 104809ace81cSJeff Dike while((req = elv_next_request(q)) != NULL){ 104991acb21fSJeff Dike err = prepare_request(req, &io_req); 105091acb21fSJeff Dike if(!err){ 105191acb21fSJeff Dike do_io(&io_req); 105291acb21fSJeff Dike __ubd_finish(req, io_req.error); 10531da177e4SLinus Torvalds } 10541da177e4SLinus Torvalds } 105591acb21fSJeff Dike } 105691acb21fSJeff Dike else { 105791acb21fSJeff Dike if(do_ubd || (req = elv_next_request(q)) == NULL) 105891acb21fSJeff Dike return; 105991acb21fSJeff Dike err = prepare_request(req, &io_req); 106091acb21fSJeff Dike if(!err){ 10612fe30a34SPaolo 'Blaisorblade' Giarrusso do_ubd = 1; 106291acb21fSJeff Dike n = os_write_file(thread_fd, (char *) &io_req, 106391acb21fSJeff Dike sizeof(io_req)); 106491acb21fSJeff Dike if(n != sizeof(io_req)) 106591acb21fSJeff Dike printk("write to io thread failed, " 106691acb21fSJeff Dike "errno = %d\n", -n); 106791acb21fSJeff Dike } 106891acb21fSJeff Dike } 10691da177e4SLinus Torvalds } 10701da177e4SLinus Torvalds 1071a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1072a885c8c4SChristoph Hellwig { 10737d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1074a885c8c4SChristoph Hellwig 1075a885c8c4SChristoph Hellwig geo->heads = 128; 1076a885c8c4SChristoph Hellwig geo->sectors = 32; 10777d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1078a885c8c4SChristoph Hellwig return 0; 1079a885c8c4SChristoph Hellwig } 1080a885c8c4SChristoph Hellwig 10811da177e4SLinus Torvalds static int ubd_ioctl(struct inode * inode, struct file * file, 10821da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 10831da177e4SLinus Torvalds { 10847d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = inode->i_bdev->bd_disk->private_data; 10851da177e4SLinus Torvalds struct hd_driveid ubd_id = { 10861da177e4SLinus Torvalds .cyls = 0, 10871da177e4SLinus Torvalds .heads = 128, 10881da177e4SLinus Torvalds .sectors = 32, 10891da177e4SLinus Torvalds }; 10901da177e4SLinus Torvalds 10911da177e4SLinus Torvalds switch (cmd) { 10921da177e4SLinus Torvalds struct cdrom_volctrl volume; 10931da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 10947d314e34SPaolo 'Blaisorblade' Giarrusso ubd_id.cyls = ubd_dev->size / (128 * 32 * 512); 10951da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 10961da177e4SLinus Torvalds sizeof(ubd_id))) 10971da177e4SLinus Torvalds return(-EFAULT); 10981da177e4SLinus Torvalds return(0); 10991da177e4SLinus Torvalds 11001da177e4SLinus Torvalds case CDROMVOLREAD: 11011da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 11021da177e4SLinus Torvalds return(-EFAULT); 11031da177e4SLinus Torvalds volume.channel0 = 255; 11041da177e4SLinus Torvalds volume.channel1 = 255; 11051da177e4SLinus Torvalds volume.channel2 = 255; 11061da177e4SLinus Torvalds volume.channel3 = 255; 11071da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 11081da177e4SLinus Torvalds return(-EFAULT); 11091da177e4SLinus Torvalds return(0); 11101da177e4SLinus Torvalds } 11111da177e4SLinus Torvalds return(-EINVAL); 11121da177e4SLinus Torvalds } 11131da177e4SLinus Torvalds 11144833aff7SPaolo 'Blaisorblade' Giarrusso static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 11151da177e4SLinus Torvalds { 11161da177e4SLinus Torvalds struct uml_stat buf1, buf2; 11171da177e4SLinus Torvalds int err; 11181da177e4SLinus Torvalds 11194833aff7SPaolo 'Blaisorblade' Giarrusso if(from_cmdline == NULL) 11204833aff7SPaolo 'Blaisorblade' Giarrusso return 0; 11214833aff7SPaolo 'Blaisorblade' Giarrusso if(!strcmp(from_cmdline, from_cow)) 11224833aff7SPaolo 'Blaisorblade' Giarrusso return 0; 11231da177e4SLinus Torvalds 11241da177e4SLinus Torvalds err = os_stat_file(from_cmdline, &buf1); 11251da177e4SLinus Torvalds if(err < 0){ 11261da177e4SLinus Torvalds printk("Couldn't stat '%s', err = %d\n", from_cmdline, -err); 11274833aff7SPaolo 'Blaisorblade' Giarrusso return 0; 11281da177e4SLinus Torvalds } 11291da177e4SLinus Torvalds err = os_stat_file(from_cow, &buf2); 11301da177e4SLinus Torvalds if(err < 0){ 11311da177e4SLinus Torvalds printk("Couldn't stat '%s', err = %d\n", from_cow, -err); 11324833aff7SPaolo 'Blaisorblade' Giarrusso return 1; 11331da177e4SLinus Torvalds } 11341da177e4SLinus Torvalds if((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 11354833aff7SPaolo 'Blaisorblade' Giarrusso return 0; 11361da177e4SLinus Torvalds 11371da177e4SLinus Torvalds printk("Backing file mismatch - \"%s\" requested,\n" 11381da177e4SLinus Torvalds "\"%s\" specified in COW header of \"%s\"\n", 11391da177e4SLinus Torvalds from_cmdline, from_cow, cow); 11404833aff7SPaolo 'Blaisorblade' Giarrusso return 1; 11411da177e4SLinus Torvalds } 11421da177e4SLinus Torvalds 11431da177e4SLinus Torvalds static int backing_file_mismatch(char *file, __u64 size, time_t mtime) 11441da177e4SLinus Torvalds { 11451da177e4SLinus Torvalds unsigned long modtime; 1146fe1db50cSPaolo 'Blaisorblade' Giarrusso unsigned long long actual; 11471da177e4SLinus Torvalds int err; 11481da177e4SLinus Torvalds 11491da177e4SLinus Torvalds err = os_file_modtime(file, &modtime); 11501da177e4SLinus Torvalds if(err < 0){ 11511da177e4SLinus Torvalds printk("Failed to get modification time of backing file " 11521da177e4SLinus Torvalds "\"%s\", err = %d\n", file, -err); 11531da177e4SLinus Torvalds return(err); 11541da177e4SLinus Torvalds } 11551da177e4SLinus Torvalds 11561da177e4SLinus Torvalds err = os_file_size(file, &actual); 11571da177e4SLinus Torvalds if(err < 0){ 11581da177e4SLinus Torvalds printk("Failed to get size of backing file \"%s\", " 11591da177e4SLinus Torvalds "err = %d\n", file, -err); 11601da177e4SLinus Torvalds return(err); 11611da177e4SLinus Torvalds } 11621da177e4SLinus Torvalds 11631da177e4SLinus Torvalds if(actual != size){ 11641da177e4SLinus Torvalds /*__u64 can be a long on AMD64 and with %lu GCC complains; so 11651da177e4SLinus Torvalds * the typecast.*/ 11661da177e4SLinus Torvalds printk("Size mismatch (%llu vs %llu) of COW header vs backing " 11671da177e4SLinus Torvalds "file\n", (unsigned long long) size, actual); 11681da177e4SLinus Torvalds return(-EINVAL); 11691da177e4SLinus Torvalds } 11701da177e4SLinus Torvalds if(modtime != mtime){ 11711da177e4SLinus Torvalds printk("mtime mismatch (%ld vs %ld) of COW header vs backing " 11721da177e4SLinus Torvalds "file\n", mtime, modtime); 11731da177e4SLinus Torvalds return(-EINVAL); 11741da177e4SLinus Torvalds } 11751da177e4SLinus Torvalds return(0); 11761da177e4SLinus Torvalds } 11771da177e4SLinus Torvalds 11781da177e4SLinus Torvalds int read_cow_bitmap(int fd, void *buf, int offset, int len) 11791da177e4SLinus Torvalds { 11801da177e4SLinus Torvalds int err; 11811da177e4SLinus Torvalds 11821da177e4SLinus Torvalds err = os_seek_file(fd, offset); 11831da177e4SLinus Torvalds if(err < 0) 11841da177e4SLinus Torvalds return(err); 11851da177e4SLinus Torvalds 11861da177e4SLinus Torvalds err = os_read_file(fd, buf, len); 11871da177e4SLinus Torvalds if(err < 0) 11881da177e4SLinus Torvalds return(err); 11891da177e4SLinus Torvalds 11901da177e4SLinus Torvalds return(0); 11911da177e4SLinus Torvalds } 11921da177e4SLinus Torvalds 11936c29256cSJeff Dike int open_ubd_file(char *file, struct openflags *openflags, int shared, 11941da177e4SLinus Torvalds char **backing_file_out, int *bitmap_offset_out, 11951da177e4SLinus Torvalds unsigned long *bitmap_len_out, int *data_offset_out, 11961da177e4SLinus Torvalds int *create_cow_out) 11971da177e4SLinus Torvalds { 11981da177e4SLinus Torvalds time_t mtime; 11991da177e4SLinus Torvalds unsigned long long size; 12001da177e4SLinus Torvalds __u32 version, align; 12011da177e4SLinus Torvalds char *backing_file; 12024833aff7SPaolo 'Blaisorblade' Giarrusso int fd, err, sectorsize, asked_switch, mode = 0644; 12031da177e4SLinus Torvalds 12041da177e4SLinus Torvalds fd = os_open_file(file, *openflags, mode); 12051da177e4SLinus Torvalds if (fd < 0) { 12061da177e4SLinus Torvalds if ((fd == -ENOENT) && (create_cow_out != NULL)) 12071da177e4SLinus Torvalds *create_cow_out = 1; 12081da177e4SLinus Torvalds if (!openflags->w || 1209a374a48fSPaolo 'Blaisorblade' Giarrusso ((fd != -EROFS) && (fd != -EACCES))) 1210a374a48fSPaolo 'Blaisorblade' Giarrusso return fd; 12111da177e4SLinus Torvalds openflags->w = 0; 12121da177e4SLinus Torvalds fd = os_open_file(file, *openflags, mode); 12131da177e4SLinus Torvalds if (fd < 0) 1214a374a48fSPaolo 'Blaisorblade' Giarrusso return fd; 12151da177e4SLinus Torvalds } 12161da177e4SLinus Torvalds 12176c29256cSJeff Dike if(shared) 12186c29256cSJeff Dike printk("Not locking \"%s\" on the host\n", file); 12196c29256cSJeff Dike else { 12201da177e4SLinus Torvalds err = os_lock_file(fd, openflags->w); 12211da177e4SLinus Torvalds if(err < 0){ 12221da177e4SLinus Torvalds printk("Failed to lock '%s', err = %d\n", file, -err); 12231da177e4SLinus Torvalds goto out_close; 12241da177e4SLinus Torvalds } 12256c29256cSJeff Dike } 12261da177e4SLinus Torvalds 1227d6e05edcSAndreas Mohr /* Successful return case! */ 1228a374a48fSPaolo 'Blaisorblade' Giarrusso if(backing_file_out == NULL) 1229a374a48fSPaolo 'Blaisorblade' Giarrusso return(fd); 12301da177e4SLinus Torvalds 12311da177e4SLinus Torvalds err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 12321da177e4SLinus Torvalds &size, §orsize, &align, bitmap_offset_out); 12331da177e4SLinus Torvalds if(err && (*backing_file_out != NULL)){ 12341da177e4SLinus Torvalds printk("Failed to read COW header from COW file \"%s\", " 12351da177e4SLinus Torvalds "errno = %d\n", file, -err); 12361da177e4SLinus Torvalds goto out_close; 12371da177e4SLinus Torvalds } 1238a374a48fSPaolo 'Blaisorblade' Giarrusso if(err) 1239a374a48fSPaolo 'Blaisorblade' Giarrusso return(fd); 12401da177e4SLinus Torvalds 12414833aff7SPaolo 'Blaisorblade' Giarrusso asked_switch = path_requires_switch(*backing_file_out, backing_file, file); 12421da177e4SLinus Torvalds 12434833aff7SPaolo 'Blaisorblade' Giarrusso /* Allow switching only if no mismatch. */ 12444833aff7SPaolo 'Blaisorblade' Giarrusso if (asked_switch && !backing_file_mismatch(*backing_file_out, size, mtime)) { 12451da177e4SLinus Torvalds printk("Switching backing file to '%s'\n", *backing_file_out); 12461da177e4SLinus Torvalds err = write_cow_header(file, fd, *backing_file_out, 12471da177e4SLinus Torvalds sectorsize, align, &size); 12481da177e4SLinus Torvalds if (err) { 12491da177e4SLinus Torvalds printk("Switch failed, errno = %d\n", -err); 12504833aff7SPaolo 'Blaisorblade' Giarrusso goto out_close; 12511da177e4SLinus Torvalds } 1252a374a48fSPaolo 'Blaisorblade' Giarrusso } else { 12531da177e4SLinus Torvalds *backing_file_out = backing_file; 12541da177e4SLinus Torvalds err = backing_file_mismatch(*backing_file_out, size, mtime); 1255a374a48fSPaolo 'Blaisorblade' Giarrusso if (err) 1256a374a48fSPaolo 'Blaisorblade' Giarrusso goto out_close; 12571da177e4SLinus Torvalds } 12581da177e4SLinus Torvalds 12591da177e4SLinus Torvalds cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 12601da177e4SLinus Torvalds bitmap_len_out, data_offset_out); 12611da177e4SLinus Torvalds 1262a374a48fSPaolo 'Blaisorblade' Giarrusso return fd; 12631da177e4SLinus Torvalds out_close: 12641da177e4SLinus Torvalds os_close_file(fd); 1265a374a48fSPaolo 'Blaisorblade' Giarrusso return err; 12661da177e4SLinus Torvalds } 12671da177e4SLinus Torvalds 12681da177e4SLinus Torvalds int create_cow_file(char *cow_file, char *backing_file, struct openflags flags, 12691da177e4SLinus Torvalds int sectorsize, int alignment, int *bitmap_offset_out, 12701da177e4SLinus Torvalds unsigned long *bitmap_len_out, int *data_offset_out) 12711da177e4SLinus Torvalds { 12721da177e4SLinus Torvalds int err, fd; 12731da177e4SLinus Torvalds 12741da177e4SLinus Torvalds flags.c = 1; 12756c29256cSJeff Dike fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 12761da177e4SLinus Torvalds if(fd < 0){ 12771da177e4SLinus Torvalds err = fd; 12781da177e4SLinus Torvalds printk("Open of COW file '%s' failed, errno = %d\n", cow_file, 12791da177e4SLinus Torvalds -err); 12801da177e4SLinus Torvalds goto out; 12811da177e4SLinus Torvalds } 12821da177e4SLinus Torvalds 12831da177e4SLinus Torvalds err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 12841da177e4SLinus Torvalds bitmap_offset_out, bitmap_len_out, 12851da177e4SLinus Torvalds data_offset_out); 12861da177e4SLinus Torvalds if(!err) 12871da177e4SLinus Torvalds return(fd); 12881da177e4SLinus Torvalds os_close_file(fd); 12891da177e4SLinus Torvalds out: 12901da177e4SLinus Torvalds return(err); 12911da177e4SLinus Torvalds } 12921da177e4SLinus Torvalds 129391acb21fSJeff Dike static int update_bitmap(struct io_thread_req *req) 12941da177e4SLinus Torvalds { 129591acb21fSJeff Dike int n; 129691acb21fSJeff Dike 129791acb21fSJeff Dike if(req->cow_offset == -1) 129891acb21fSJeff Dike return(0); 129991acb21fSJeff Dike 130091acb21fSJeff Dike n = os_seek_file(req->fds[1], req->cow_offset); 130191acb21fSJeff Dike if(n < 0){ 130291acb21fSJeff Dike printk("do_io - bitmap lseek failed : err = %d\n", -n); 130391acb21fSJeff Dike return(1); 130491acb21fSJeff Dike } 130591acb21fSJeff Dike 130691acb21fSJeff Dike n = os_write_file(req->fds[1], &req->bitmap_words, 130791acb21fSJeff Dike sizeof(req->bitmap_words)); 130891acb21fSJeff Dike if(n != sizeof(req->bitmap_words)){ 130991acb21fSJeff Dike printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, 131091acb21fSJeff Dike req->fds[1]); 131191acb21fSJeff Dike return(1); 131291acb21fSJeff Dike } 131391acb21fSJeff Dike 131491acb21fSJeff Dike return(0); 131591acb21fSJeff Dike } 131691acb21fSJeff Dike 131791acb21fSJeff Dike void do_io(struct io_thread_req *req) 131891acb21fSJeff Dike { 13191da177e4SLinus Torvalds char *buf; 132091acb21fSJeff Dike unsigned long len; 132191acb21fSJeff Dike int n, nsectors, start, end, bit; 132291acb21fSJeff Dike int err; 13231da177e4SLinus Torvalds __u64 off; 13241da177e4SLinus Torvalds 13251da177e4SLinus Torvalds nsectors = req->length / req->sectorsize; 13261da177e4SLinus Torvalds start = 0; 13271da177e4SLinus Torvalds do { 132891acb21fSJeff Dike bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); 13291da177e4SLinus Torvalds end = start; 13301da177e4SLinus Torvalds while((end < nsectors) && 133191acb21fSJeff Dike (ubd_test_bit(end, (unsigned char *) 133291acb21fSJeff Dike &req->sector_mask) == bit)) 13331da177e4SLinus Torvalds end++; 13341da177e4SLinus Torvalds 133591acb21fSJeff Dike off = req->offset + req->offsets[bit] + 13361da177e4SLinus Torvalds start * req->sectorsize; 13371da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 13381da177e4SLinus Torvalds buf = &req->buffer[start * req->sectorsize]; 13391da177e4SLinus Torvalds 134091acb21fSJeff Dike err = os_seek_file(req->fds[bit], off); 134191acb21fSJeff Dike if(err < 0){ 134291acb21fSJeff Dike printk("do_io - lseek failed : err = %d\n", -err); 13431da177e4SLinus Torvalds req->error = 1; 13441da177e4SLinus Torvalds return; 13451da177e4SLinus Torvalds } 134691acb21fSJeff Dike if(req->op == UBD_READ){ 134791acb21fSJeff Dike n = 0; 134891acb21fSJeff Dike do { 134991acb21fSJeff Dike buf = &buf[n]; 135091acb21fSJeff Dike len -= n; 135191acb21fSJeff Dike n = os_read_file(req->fds[bit], buf, len); 135291acb21fSJeff Dike if (n < 0) { 135391acb21fSJeff Dike printk("do_io - read failed, err = %d " 135491acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 13551da177e4SLinus Torvalds req->error = 1; 13561da177e4SLinus Torvalds return; 13571da177e4SLinus Torvalds } 135891acb21fSJeff Dike } while((n < len) && (n != 0)); 135991acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 136091acb21fSJeff Dike } else { 136191acb21fSJeff Dike n = os_write_file(req->fds[bit], buf, len); 136291acb21fSJeff Dike if(n != len){ 136391acb21fSJeff Dike printk("do_io - write failed err = %d " 136491acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 136591acb21fSJeff Dike req->error = 1; 136691acb21fSJeff Dike return; 136791acb21fSJeff Dike } 136891acb21fSJeff Dike } 13691da177e4SLinus Torvalds 13701da177e4SLinus Torvalds start = end; 13711da177e4SLinus Torvalds } while(start < nsectors); 137291acb21fSJeff Dike 137391acb21fSJeff Dike req->error = update_bitmap(req); 13741da177e4SLinus Torvalds } 137591acb21fSJeff Dike 137691acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 137791acb21fSJeff Dike * from ubd_init, which is an initcall. 137891acb21fSJeff Dike */ 137991acb21fSJeff Dike int kernel_fd = -1; 138091acb21fSJeff Dike 138191acb21fSJeff Dike /* Only changed by the io thread */ 138291acb21fSJeff Dike int io_count = 0; 138391acb21fSJeff Dike 138491acb21fSJeff Dike int io_thread(void *arg) 138591acb21fSJeff Dike { 138691acb21fSJeff Dike struct io_thread_req req; 138791acb21fSJeff Dike int n; 138891acb21fSJeff Dike 138991acb21fSJeff Dike ignore_sigwinch_sig(); 139091acb21fSJeff Dike while(1){ 139191acb21fSJeff Dike n = os_read_file(kernel_fd, &req, sizeof(req)); 139291acb21fSJeff Dike if(n != sizeof(req)){ 139391acb21fSJeff Dike if(n < 0) 139491acb21fSJeff Dike printk("io_thread - read failed, fd = %d, " 139591acb21fSJeff Dike "err = %d\n", kernel_fd, -n); 139691acb21fSJeff Dike else { 139791acb21fSJeff Dike printk("io_thread - short read, fd = %d, " 139891acb21fSJeff Dike "length = %d\n", kernel_fd, n); 139991acb21fSJeff Dike } 140091acb21fSJeff Dike continue; 140191acb21fSJeff Dike } 140291acb21fSJeff Dike io_count++; 140391acb21fSJeff Dike do_io(&req); 140491acb21fSJeff Dike n = os_write_file(kernel_fd, &req, sizeof(req)); 140591acb21fSJeff Dike if(n != sizeof(req)) 140691acb21fSJeff Dike printk("io_thread - write failed, fd = %d, err = %d\n", 140791acb21fSJeff Dike kernel_fd, -n); 140891acb21fSJeff Dike } 140991acb21fSJeff Dike 14101b57e9c2SJeff Dike return 0; 14111b57e9c2SJeff Dike } 1412