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 UBD_SHIFT 4 211da177e4SLinus Torvalds 22e16f5350SJeff Dike #include "linux/kernel.h" 231da177e4SLinus Torvalds #include "linux/module.h" 241da177e4SLinus Torvalds #include "linux/blkdev.h" 2573855e13SBartlomiej Zolnierkiewicz #include "linux/ata.h" 261da177e4SLinus Torvalds #include "linux/hdreg.h" 271da177e4SLinus Torvalds #include "linux/init.h" 281da177e4SLinus Torvalds #include "linux/cdrom.h" 291da177e4SLinus Torvalds #include "linux/proc_fs.h" 306613c5e8SAlexey Dobriyan #include "linux/seq_file.h" 311da177e4SLinus Torvalds #include "linux/ctype.h" 321da177e4SLinus Torvalds #include "linux/capability.h" 331da177e4SLinus Torvalds #include "linux/mm.h" 345a0e3ad6STejun Heo #include "linux/slab.h" 351da177e4SLinus Torvalds #include "linux/vmalloc.h" 369a181c58SArnd Bergmann #include "linux/mutex.h" 371da177e4SLinus Torvalds #include "linux/blkpg.h" 381da177e4SLinus Torvalds #include "linux/genhd.h" 391da177e4SLinus Torvalds #include "linux/spinlock.h" 40d052d1beSRussell King #include "linux/platform_device.h" 4123464ffaSWANG Cong #include "linux/scatterlist.h" 421da177e4SLinus Torvalds #include "asm/segment.h" 431da177e4SLinus Torvalds #include "asm/uaccess.h" 441da177e4SLinus Torvalds #include "asm/irq.h" 451da177e4SLinus Torvalds #include "asm/types.h" 461da177e4SLinus Torvalds #include "asm/tlbflush.h" 471da177e4SLinus Torvalds #include "mem_user.h" 481da177e4SLinus Torvalds #include "kern_util.h" 491da177e4SLinus Torvalds #include "kern.h" 501da177e4SLinus Torvalds #include "mconsole_kern.h" 511da177e4SLinus Torvalds #include "init.h" 521da177e4SLinus Torvalds #include "irq_user.h" 531da177e4SLinus Torvalds #include "irq_kern.h" 541da177e4SLinus Torvalds #include "ubd_user.h" 551da177e4SLinus Torvalds #include "os.h" 561da177e4SLinus Torvalds #include "mem.h" 571da177e4SLinus Torvalds #include "mem_kern.h" 581da177e4SLinus Torvalds #include "cow.h" 591da177e4SLinus Torvalds 607b9014c1SJeff Dike enum ubd_req { UBD_READ, UBD_WRITE }; 611da177e4SLinus Torvalds 621da177e4SLinus Torvalds struct io_thread_req { 6362f96cb0SJeff Dike struct request *req; 6491acb21fSJeff Dike enum ubd_req op; 651da177e4SLinus Torvalds int fds[2]; 661da177e4SLinus Torvalds unsigned long offsets[2]; 671da177e4SLinus Torvalds unsigned long long offset; 681da177e4SLinus Torvalds unsigned long length; 691da177e4SLinus Torvalds char *buffer; 701da177e4SLinus Torvalds int sectorsize; 7191acb21fSJeff Dike unsigned long sector_mask; 7291acb21fSJeff Dike unsigned long long cow_offset; 7391acb21fSJeff Dike unsigned long bitmap_words[2]; 741da177e4SLinus Torvalds int error; 751da177e4SLinus Torvalds }; 761da177e4SLinus Torvalds 7791acb21fSJeff Dike static inline int ubd_test_bit(__u64 bit, unsigned char *data) 781da177e4SLinus Torvalds { 791da177e4SLinus Torvalds __u64 n; 801da177e4SLinus Torvalds int bits, off; 811da177e4SLinus Torvalds 8291acb21fSJeff Dike bits = sizeof(data[0]) * 8; 831da177e4SLinus Torvalds n = bit / bits; 841da177e4SLinus Torvalds off = bit % bits; 85dc764e50SJeff Dike return (data[n] & (1 << off)) != 0; 861da177e4SLinus Torvalds } 871da177e4SLinus Torvalds 8891acb21fSJeff Dike static inline void ubd_set_bit(__u64 bit, unsigned char *data) 891da177e4SLinus Torvalds { 901da177e4SLinus Torvalds __u64 n; 911da177e4SLinus Torvalds int bits, off; 921da177e4SLinus Torvalds 9391acb21fSJeff Dike bits = sizeof(data[0]) * 8; 941da177e4SLinus Torvalds n = bit / bits; 951da177e4SLinus Torvalds off = bit % bits; 9691acb21fSJeff Dike data[n] |= (1 << off); 971da177e4SLinus Torvalds } 981da177e4SLinus Torvalds /*End stuff from ubd_user.h*/ 991da177e4SLinus Torvalds 1001da177e4SLinus Torvalds #define DRIVER_NAME "uml-blkdev" 1011da177e4SLinus Torvalds 102d7fb2c38SPaolo 'Blaisorblade' Giarrusso static DEFINE_MUTEX(ubd_lock); 1039a181c58SArnd Bergmann static DEFINE_MUTEX(ubd_mutex); /* replaces BKL, might not be needed */ 1041da177e4SLinus Torvalds 105a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode); 106a625c998SAl Viro static int ubd_release(struct gendisk *disk, fmode_t mode); 107a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 1081da177e4SLinus Torvalds unsigned int cmd, unsigned long arg); 109a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); 1101da177e4SLinus Torvalds 11197d88ac8SPaolo 'Blaisorblade' Giarrusso #define MAX_DEV (16) 1121da177e4SLinus Torvalds 11383d5cde4SAlexey Dobriyan static const struct block_device_operations ubd_blops = { 1141da177e4SLinus Torvalds .owner = THIS_MODULE, 115a625c998SAl Viro .open = ubd_open, 116a625c998SAl Viro .release = ubd_release, 117a625c998SAl Viro .ioctl = ubd_ioctl, 118a885c8c4SChristoph Hellwig .getgeo = ubd_getgeo, 1191da177e4SLinus Torvalds }; 1201da177e4SLinus Torvalds 1211da177e4SLinus Torvalds /* Protected by ubd_lock */ 122792dd4fcSChristoph Hellwig static int fake_major = UBD_MAJOR; 1231da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1241da177e4SLinus Torvalds static struct gendisk *fake_gendisk[MAX_DEV]; 1251da177e4SLinus Torvalds 1261da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1271da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1281da177e4SLinus Torvalds .cl = 1 }) 1291da177e4SLinus Torvalds #else 1301da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1311da177e4SLinus Torvalds .cl = 1 }) 1321da177e4SLinus Torvalds #endif 1331da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1341da177e4SLinus Torvalds 1351da177e4SLinus Torvalds struct cow { 1362a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file name */ 1371da177e4SLinus Torvalds char *file; 1382a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file fd */ 1391da177e4SLinus Torvalds int fd; 1401da177e4SLinus Torvalds unsigned long *bitmap; 1411da177e4SLinus Torvalds unsigned long bitmap_len; 1421da177e4SLinus Torvalds int bitmap_offset; 1431da177e4SLinus Torvalds int data_offset; 1441da177e4SLinus Torvalds }; 1451da177e4SLinus Torvalds 146a0044bdfSJeff Dike #define MAX_SG 64 147a0044bdfSJeff Dike 1481da177e4SLinus Torvalds struct ubd { 149a0044bdfSJeff Dike struct list_head restart; 1502a9d32f6SPaolo 'Blaisorblade' Giarrusso /* name (and fd, below) of the file opened for writing, either the 1512a9d32f6SPaolo 'Blaisorblade' Giarrusso * backing or the cow file. */ 1521da177e4SLinus Torvalds char *file; 1531da177e4SLinus Torvalds int count; 1541da177e4SLinus Torvalds int fd; 1551da177e4SLinus Torvalds __u64 size; 1561da177e4SLinus Torvalds struct openflags boot_openflags; 1571da177e4SLinus Torvalds struct openflags openflags; 15884e945e3SPaolo 'Blaisorblade' Giarrusso unsigned shared:1; 15984e945e3SPaolo 'Blaisorblade' Giarrusso unsigned no_cow:1; 1601da177e4SLinus Torvalds struct cow cow; 1611da177e4SLinus Torvalds struct platform_device pdev; 16262f96cb0SJeff Dike struct request_queue *queue; 16362f96cb0SJeff Dike spinlock_t lock; 164a0044bdfSJeff Dike struct scatterlist sg[MAX_SG]; 165a0044bdfSJeff Dike struct request *request; 166a0044bdfSJeff Dike int start_sg, end_sg; 16747526903STejun Heo sector_t rq_pos; 1681da177e4SLinus Torvalds }; 1691da177e4SLinus Torvalds 1701da177e4SLinus Torvalds #define DEFAULT_COW { \ 1711da177e4SLinus Torvalds .file = NULL, \ 1721da177e4SLinus Torvalds .fd = -1, \ 1731da177e4SLinus Torvalds .bitmap = NULL, \ 1741da177e4SLinus Torvalds .bitmap_offset = 0, \ 1751da177e4SLinus Torvalds .data_offset = 0, \ 1761da177e4SLinus Torvalds } 1771da177e4SLinus Torvalds 1781da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1791da177e4SLinus Torvalds .file = NULL, \ 1801da177e4SLinus Torvalds .count = 0, \ 1811da177e4SLinus Torvalds .fd = -1, \ 1821da177e4SLinus Torvalds .size = -1, \ 1831da177e4SLinus Torvalds .boot_openflags = OPEN_FLAGS, \ 1841da177e4SLinus Torvalds .openflags = OPEN_FLAGS, \ 1851da177e4SLinus Torvalds .no_cow = 0, \ 1866c29256cSJeff Dike .shared = 0, \ 1871da177e4SLinus Torvalds .cow = DEFAULT_COW, \ 18822e65004SThomas Gleixner .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \ 189a0044bdfSJeff Dike .request = NULL, \ 190a0044bdfSJeff Dike .start_sg = 0, \ 191a0044bdfSJeff Dike .end_sg = 0, \ 19247526903STejun Heo .rq_pos = 0, \ 1931da177e4SLinus Torvalds } 1941da177e4SLinus Torvalds 195b8831a1dSJeff Dike /* Protected by ubd_lock */ 1965dc62b1bSWANG Cong static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; 1971da177e4SLinus Torvalds 1981da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 1991da177e4SLinus Torvalds static int fake_ide = 0; 2001da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 2011da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 2021da177e4SLinus Torvalds 2031da177e4SLinus Torvalds static void make_proc_ide(void) 2041da177e4SLinus Torvalds { 2051da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 2061da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 2071da177e4SLinus Torvalds } 2081da177e4SLinus Torvalds 2096613c5e8SAlexey Dobriyan static int fake_ide_media_proc_show(struct seq_file *m, void *v) 2101da177e4SLinus Torvalds { 2116613c5e8SAlexey Dobriyan seq_puts(m, "disk\n"); 2126613c5e8SAlexey Dobriyan return 0; 2136613c5e8SAlexey Dobriyan } 2141da177e4SLinus Torvalds 2156613c5e8SAlexey Dobriyan static int fake_ide_media_proc_open(struct inode *inode, struct file *file) 2166613c5e8SAlexey Dobriyan { 2176613c5e8SAlexey Dobriyan return single_open(file, fake_ide_media_proc_show, NULL); 2181da177e4SLinus Torvalds } 2196613c5e8SAlexey Dobriyan 2206613c5e8SAlexey Dobriyan static const struct file_operations fake_ide_media_proc_fops = { 2216613c5e8SAlexey Dobriyan .owner = THIS_MODULE, 2226613c5e8SAlexey Dobriyan .open = fake_ide_media_proc_open, 2236613c5e8SAlexey Dobriyan .read = seq_read, 2246613c5e8SAlexey Dobriyan .llseek = seq_lseek, 2256613c5e8SAlexey Dobriyan .release = single_release, 2266613c5e8SAlexey Dobriyan }; 2271da177e4SLinus Torvalds 228c0a9290eSWANG Cong static void make_ide_entries(const char *dev_name) 2291da177e4SLinus Torvalds { 2301da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2311da177e4SLinus Torvalds char name[64]; 2321da177e4SLinus Torvalds 2331da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2341da177e4SLinus Torvalds 2351da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2361da177e4SLinus Torvalds if(!dir) return; 2371da177e4SLinus Torvalds 2386613c5e8SAlexey Dobriyan ent = proc_create("media", S_IRUGO, dir, &fake_ide_media_proc_fops); 2391da177e4SLinus Torvalds if(!ent) return; 240c0a9290eSWANG Cong snprintf(name, sizeof(name), "ide0/%s", dev_name); 2411da177e4SLinus Torvalds proc_symlink(dev_name, proc_ide_root, name); 2421da177e4SLinus Torvalds } 2431da177e4SLinus Torvalds 2441da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2451da177e4SLinus Torvalds { 2461da177e4SLinus Torvalds fake_ide = 1; 247dc764e50SJeff Dike return 1; 2481da177e4SLinus Torvalds } 2491da177e4SLinus Torvalds 2501da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2511da177e4SLinus Torvalds 2521da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2531da177e4SLinus Torvalds "fake_ide\n" 2541da177e4SLinus Torvalds " Create ide0 entries that map onto ubd devices.\n\n" 2551da177e4SLinus Torvalds ); 2561da177e4SLinus Torvalds 2571da177e4SLinus Torvalds static int parse_unit(char **ptr) 2581da177e4SLinus Torvalds { 2591da177e4SLinus Torvalds char *str = *ptr, *end; 2601da177e4SLinus Torvalds int n = -1; 2611da177e4SLinus Torvalds 2621da177e4SLinus Torvalds if(isdigit(*str)) { 2631da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2641da177e4SLinus Torvalds if(end == str) 265dc764e50SJeff Dike return -1; 2661da177e4SLinus Torvalds *ptr = end; 2671da177e4SLinus Torvalds } 26897d88ac8SPaolo 'Blaisorblade' Giarrusso else if (('a' <= *str) && (*str <= 'z')) { 2691da177e4SLinus Torvalds n = *str - 'a'; 2701da177e4SLinus Torvalds str++; 2711da177e4SLinus Torvalds *ptr = str; 2721da177e4SLinus Torvalds } 273dc764e50SJeff Dike return n; 2741da177e4SLinus Torvalds } 2751da177e4SLinus Torvalds 276d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* If *index_out == -1 at exit, the passed option was a general one; 277d8d7c28eSPaolo 'Blaisorblade' Giarrusso * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it 278d8d7c28eSPaolo 'Blaisorblade' Giarrusso * should not be freed on exit. 279d8d7c28eSPaolo 'Blaisorblade' Giarrusso */ 280f28169d2SJeff Dike static int ubd_setup_common(char *str, int *index_out, char **error_out) 2811da177e4SLinus Torvalds { 2827d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 2831da177e4SLinus Torvalds struct openflags flags = global_openflags; 2841da177e4SLinus Torvalds char *backing_file; 285b8831a1dSJeff Dike int n, err = 0, i; 2861da177e4SLinus Torvalds 2871da177e4SLinus Torvalds if(index_out) *index_out = -1; 2881da177e4SLinus Torvalds n = *str; 2891da177e4SLinus Torvalds if(n == '='){ 2901da177e4SLinus Torvalds char *end; 2911da177e4SLinus Torvalds int major; 2921da177e4SLinus Torvalds 2931da177e4SLinus Torvalds str++; 2941da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 2951da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 296b8831a1dSJeff Dike goto out1; 2971da177e4SLinus Torvalds } 2981da177e4SLinus Torvalds 299f28169d2SJeff Dike err = -EINVAL; 300b8831a1dSJeff Dike major = simple_strtoul(str, &end, 0); 301b8831a1dSJeff Dike if((*end != '\0') || (end == str)){ 302b8831a1dSJeff Dike *error_out = "Didn't parse major number"; 303b8831a1dSJeff Dike goto out1; 304b8831a1dSJeff Dike } 305b8831a1dSJeff Dike 306d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 307792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 308f28169d2SJeff Dike *error_out = "Can't assign a fake major twice"; 3091da177e4SLinus Torvalds goto out1; 3101da177e4SLinus Torvalds } 3111da177e4SLinus Torvalds 3121da177e4SLinus Torvalds fake_major = major; 3131da177e4SLinus Torvalds 3141da177e4SLinus Torvalds printk(KERN_INFO "Setting extra ubd major number to %d\n", 3151da177e4SLinus Torvalds major); 3161da177e4SLinus Torvalds err = 0; 3171da177e4SLinus Torvalds out1: 318d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 319f28169d2SJeff Dike return err; 3201da177e4SLinus Torvalds } 3211da177e4SLinus Torvalds 3221da177e4SLinus Torvalds n = parse_unit(&str); 3231da177e4SLinus Torvalds if(n < 0){ 324f28169d2SJeff Dike *error_out = "Couldn't parse device number"; 325f28169d2SJeff Dike return -EINVAL; 3261da177e4SLinus Torvalds } 3271da177e4SLinus Torvalds if(n >= MAX_DEV){ 328f28169d2SJeff Dike *error_out = "Device number out of range"; 329f28169d2SJeff Dike return 1; 3301da177e4SLinus Torvalds } 3311da177e4SLinus Torvalds 332f28169d2SJeff Dike err = -EBUSY; 333d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 3341da177e4SLinus Torvalds 3357d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 3367d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file != NULL){ 337f28169d2SJeff Dike *error_out = "Device is already configured"; 3381da177e4SLinus Torvalds goto out; 3391da177e4SLinus Torvalds } 3401da177e4SLinus Torvalds 3411da177e4SLinus Torvalds if (index_out) 3421da177e4SLinus Torvalds *index_out = n; 3431da177e4SLinus Torvalds 344f28169d2SJeff Dike err = -EINVAL; 3456c29256cSJeff Dike for (i = 0; i < sizeof("rscd="); i++) { 3461da177e4SLinus Torvalds switch (*str) { 3471da177e4SLinus Torvalds case 'r': 3481da177e4SLinus Torvalds flags.w = 0; 3491da177e4SLinus Torvalds break; 3501da177e4SLinus Torvalds case 's': 3511da177e4SLinus Torvalds flags.s = 1; 3521da177e4SLinus Torvalds break; 3531da177e4SLinus Torvalds case 'd': 3547d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->no_cow = 1; 3551da177e4SLinus Torvalds break; 3566c29256cSJeff Dike case 'c': 3577d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->shared = 1; 3586c29256cSJeff Dike break; 3591da177e4SLinus Torvalds case '=': 3601da177e4SLinus Torvalds str++; 3611da177e4SLinus Torvalds goto break_loop; 3621da177e4SLinus Torvalds default: 363f28169d2SJeff Dike *error_out = "Expected '=' or flag letter " 364f28169d2SJeff Dike "(r, s, c, or d)"; 3651da177e4SLinus Torvalds goto out; 3661da177e4SLinus Torvalds } 3671da177e4SLinus Torvalds str++; 3681da177e4SLinus Torvalds } 3691da177e4SLinus Torvalds 3701da177e4SLinus Torvalds if (*str == '=') 371f28169d2SJeff Dike *error_out = "Too many flags specified"; 3721da177e4SLinus Torvalds else 373f28169d2SJeff Dike *error_out = "Missing '='"; 3741da177e4SLinus Torvalds goto out; 3751da177e4SLinus Torvalds 3761da177e4SLinus Torvalds break_loop: 3771da177e4SLinus Torvalds backing_file = strchr(str, ','); 3781da177e4SLinus Torvalds 379f28169d2SJeff Dike if (backing_file == NULL) 3801da177e4SLinus Torvalds backing_file = strchr(str, ':'); 3811da177e4SLinus Torvalds 382f28169d2SJeff Dike if(backing_file != NULL){ 383f28169d2SJeff Dike if(ubd_dev->no_cow){ 384f28169d2SJeff Dike *error_out = "Can't specify both 'd' and a cow file"; 385f28169d2SJeff Dike goto out; 386f28169d2SJeff Dike } 3871da177e4SLinus Torvalds else { 3881da177e4SLinus Torvalds *backing_file = '\0'; 3891da177e4SLinus Torvalds backing_file++; 3901da177e4SLinus Torvalds } 3911da177e4SLinus Torvalds } 392f28169d2SJeff Dike err = 0; 3937d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->file = str; 3947d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.file = backing_file; 3957d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->boot_openflags = flags; 3961da177e4SLinus Torvalds out: 397d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 398f28169d2SJeff Dike return err; 3991da177e4SLinus Torvalds } 4001da177e4SLinus Torvalds 4011da177e4SLinus Torvalds static int ubd_setup(char *str) 4021da177e4SLinus Torvalds { 403f28169d2SJeff Dike char *error; 404f28169d2SJeff Dike int err; 405f28169d2SJeff Dike 406f28169d2SJeff Dike err = ubd_setup_common(str, NULL, &error); 407f28169d2SJeff Dike if(err) 408f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize device with \"%s\" : " 409f28169d2SJeff Dike "%s\n", str, error); 410f28169d2SJeff Dike return 1; 4111da177e4SLinus Torvalds } 4121da177e4SLinus Torvalds 4131da177e4SLinus Torvalds __setup("ubd", ubd_setup); 4141da177e4SLinus Torvalds __uml_help(ubd_setup, 4151da177e4SLinus Torvalds "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" 4161da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 4171da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 4181da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 4191da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 4201da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 4211da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 422f28169d2SJeff Dike " When using only one filename, UML will detect whether to treat it like\n" 4231da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 4241da177e4SLinus Torvalds " flag:\n" 4251da177e4SLinus Torvalds " ubd0d=BackingFile\n" 4261da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 4271da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 4281da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 4291da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 4301da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 4311da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 4321da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 43320ede453SJeff Dike " an 's' will cause data to be written to disk on the host immediately.\n" 43420ede453SJeff Dike " 'c' will cause the device to be treated as being shared between multiple\n" 43520ede453SJeff Dike " UMLs and file locking will be turned off - this is appropriate for a\n" 43620ede453SJeff Dike " cluster filesystem and inappropriate at almost all other times.\n\n" 4371da177e4SLinus Torvalds ); 4381da177e4SLinus Torvalds 4398299ca5cSJeff Dike static int udb_setup(char *str) 4401da177e4SLinus Torvalds { 4411da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 4421da177e4SLinus Torvalds "udb TYPO\n", str); 443dc764e50SJeff Dike return 1; 4441da177e4SLinus Torvalds } 4451da177e4SLinus Torvalds 4461da177e4SLinus Torvalds __setup("udb", udb_setup); 4471da177e4SLinus Torvalds __uml_help(udb_setup, 4481da177e4SLinus Torvalds "udb\n" 4490894e27eSJeff Dike " This option is here solely to catch ubd -> udb typos, which can be\n" 4500894e27eSJeff Dike " to impossible to catch visually unless you specifically look for\n" 4510894e27eSJeff Dike " them. The only result of any option starting with 'udb' is an error\n" 4521da177e4SLinus Torvalds " in the boot output.\n\n" 4531da177e4SLinus Torvalds ); 4541da177e4SLinus Torvalds 455165125e1SJens Axboe static void do_ubd_request(struct request_queue * q); 45691acb21fSJeff Dike 45791acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 4585dc62b1bSWANG Cong static int thread_fd = -1; 459a0044bdfSJeff Dike static LIST_HEAD(restart); 46009ace81cSJeff Dike 4612fe30a34SPaolo 'Blaisorblade' Giarrusso /* XXX - move this inside ubd_intr. */ 46262f96cb0SJeff Dike /* Called without dev->lock held, and only in interrupt context. */ 46391acb21fSJeff Dike static void ubd_handler(void) 46491acb21fSJeff Dike { 4652adcec21SJeff Dike struct io_thread_req *req; 466a0044bdfSJeff Dike struct ubd *ubd; 467a0044bdfSJeff Dike struct list_head *list, *next_ele; 468a0044bdfSJeff Dike unsigned long flags; 46991acb21fSJeff Dike int n; 47009ace81cSJeff Dike 471a0044bdfSJeff Dike while(1){ 472a6ea4cceSJeff Dike n = os_read_file(thread_fd, &req, 4732adcec21SJeff Dike sizeof(struct io_thread_req *)); 47491acb21fSJeff Dike if(n != sizeof(req)){ 475a0044bdfSJeff Dike if(n == -EAGAIN) 476a0044bdfSJeff Dike break; 477a0044bdfSJeff Dike printk(KERN_ERR "spurious interrupt in ubd_handler, " 478a0044bdfSJeff Dike "err = %d\n", -n); 47991acb21fSJeff Dike return; 48091acb21fSJeff Dike } 48109ace81cSJeff Dike 4824d6c84d9STejun Heo blk_end_request(req->req, 0, req->length); 4832adcec21SJeff Dike kfree(req); 484a0044bdfSJeff Dike } 48591acb21fSJeff Dike reactivate_fd(thread_fd, UBD_IRQ); 486a0044bdfSJeff Dike 487a0044bdfSJeff Dike list_for_each_safe(list, next_ele, &restart){ 488a0044bdfSJeff Dike ubd = container_of(list, struct ubd, restart); 489a0044bdfSJeff Dike list_del_init(&ubd->restart); 490a0044bdfSJeff Dike spin_lock_irqsave(&ubd->lock, flags); 491a0044bdfSJeff Dike do_ubd_request(ubd->queue); 492a0044bdfSJeff Dike spin_unlock_irqrestore(&ubd->lock, flags); 493a0044bdfSJeff Dike } 49491acb21fSJeff Dike } 49509ace81cSJeff Dike 4967bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 4971da177e4SLinus Torvalds { 49891acb21fSJeff Dike ubd_handler(); 499dc764e50SJeff Dike return IRQ_HANDLED; 5001da177e4SLinus Torvalds } 5011da177e4SLinus Torvalds 50291acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 50391acb21fSJeff Dike static int io_pid = -1; 50491acb21fSJeff Dike 5055dc62b1bSWANG Cong static void kill_io_thread(void) 50691acb21fSJeff Dike { 50791acb21fSJeff Dike if(io_pid != -1) 50891acb21fSJeff Dike os_kill_process(io_pid, 1); 50991acb21fSJeff Dike } 51091acb21fSJeff Dike 51191acb21fSJeff Dike __uml_exitcall(kill_io_thread); 51291acb21fSJeff Dike 513d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5141da177e4SLinus Torvalds { 5151da177e4SLinus Torvalds char *file; 5161da177e4SLinus Torvalds 5177d314e34SPaolo 'Blaisorblade' Giarrusso file = ubd_dev->cow.file ? ubd_dev->cow.file : ubd_dev->file; 518dc764e50SJeff Dike return os_file_size(file, size_out); 5191da177e4SLinus Torvalds } 5201da177e4SLinus Torvalds 5215dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 5225dc62b1bSWANG Cong { 5235dc62b1bSWANG Cong int err; 5245dc62b1bSWANG Cong 5255dc62b1bSWANG Cong err = os_seek_file(fd, offset); 5265dc62b1bSWANG Cong if (err < 0) 5275dc62b1bSWANG Cong return err; 5285dc62b1bSWANG Cong 5295dc62b1bSWANG Cong err = os_read_file(fd, buf, len); 5305dc62b1bSWANG Cong if (err < 0) 5315dc62b1bSWANG Cong return err; 5325dc62b1bSWANG Cong 5335dc62b1bSWANG Cong return 0; 5345dc62b1bSWANG Cong } 5355dc62b1bSWANG Cong 5365dc62b1bSWANG Cong static int backing_file_mismatch(char *file, __u64 size, time_t mtime) 5375dc62b1bSWANG Cong { 5385dc62b1bSWANG Cong unsigned long modtime; 5395dc62b1bSWANG Cong unsigned long long actual; 5405dc62b1bSWANG Cong int err; 5415dc62b1bSWANG Cong 5425dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 5435dc62b1bSWANG Cong if (err < 0) { 5445dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 5455dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 5465dc62b1bSWANG Cong return err; 5475dc62b1bSWANG Cong } 5485dc62b1bSWANG Cong 5495dc62b1bSWANG Cong err = os_file_size(file, &actual); 5505dc62b1bSWANG Cong if (err < 0) { 5515dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 5525dc62b1bSWANG Cong "err = %d\n", file, -err); 5535dc62b1bSWANG Cong return err; 5545dc62b1bSWANG Cong } 5555dc62b1bSWANG Cong 5565dc62b1bSWANG Cong if (actual != size) { 5575dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 5585dc62b1bSWANG Cong * the typecast.*/ 5595dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 5605dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 5615dc62b1bSWANG Cong return -EINVAL; 5625dc62b1bSWANG Cong } 5635dc62b1bSWANG Cong if (modtime != mtime) { 5645dc62b1bSWANG Cong printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " 5655dc62b1bSWANG Cong "backing file\n", mtime, modtime); 5665dc62b1bSWANG Cong return -EINVAL; 5675dc62b1bSWANG Cong } 5685dc62b1bSWANG Cong return 0; 5695dc62b1bSWANG Cong } 5705dc62b1bSWANG Cong 5715dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 5725dc62b1bSWANG Cong { 5735dc62b1bSWANG Cong struct uml_stat buf1, buf2; 5745dc62b1bSWANG Cong int err; 5755dc62b1bSWANG Cong 5765dc62b1bSWANG Cong if (from_cmdline == NULL) 5775dc62b1bSWANG Cong return 0; 5785dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 5795dc62b1bSWANG Cong return 0; 5805dc62b1bSWANG Cong 5815dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 5825dc62b1bSWANG Cong if (err < 0) { 5835dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 5845dc62b1bSWANG Cong -err); 5855dc62b1bSWANG Cong return 0; 5865dc62b1bSWANG Cong } 5875dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 5885dc62b1bSWANG Cong if (err < 0) { 5895dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 5905dc62b1bSWANG Cong -err); 5915dc62b1bSWANG Cong return 1; 5925dc62b1bSWANG Cong } 5935dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 5945dc62b1bSWANG Cong return 0; 5955dc62b1bSWANG Cong 5965dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 5975dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 5985dc62b1bSWANG Cong from_cmdline, from_cow, cow); 5995dc62b1bSWANG Cong return 1; 6005dc62b1bSWANG Cong } 6015dc62b1bSWANG Cong 6025dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 6035dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 6045dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6055dc62b1bSWANG Cong int *create_cow_out) 6065dc62b1bSWANG Cong { 6075dc62b1bSWANG Cong time_t mtime; 6085dc62b1bSWANG Cong unsigned long long size; 6095dc62b1bSWANG Cong __u32 version, align; 6105dc62b1bSWANG Cong char *backing_file; 6115dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6125dc62b1bSWANG Cong 6135dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6145dc62b1bSWANG Cong if (fd < 0) { 6155dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6165dc62b1bSWANG Cong *create_cow_out = 1; 6175dc62b1bSWANG Cong if (!openflags->w || 6185dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 6195dc62b1bSWANG Cong return fd; 6205dc62b1bSWANG Cong openflags->w = 0; 6215dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6225dc62b1bSWANG Cong if (fd < 0) 6235dc62b1bSWANG Cong return fd; 6245dc62b1bSWANG Cong } 6255dc62b1bSWANG Cong 6265dc62b1bSWANG Cong if (shared) 6275dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 6285dc62b1bSWANG Cong else { 6295dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 6305dc62b1bSWANG Cong if (err < 0) { 6315dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 6325dc62b1bSWANG Cong file, -err); 6335dc62b1bSWANG Cong goto out_close; 6345dc62b1bSWANG Cong } 6355dc62b1bSWANG Cong } 6365dc62b1bSWANG Cong 6375dc62b1bSWANG Cong /* Successful return case! */ 6385dc62b1bSWANG Cong if (backing_file_out == NULL) 6395dc62b1bSWANG Cong return fd; 6405dc62b1bSWANG Cong 6415dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 6425dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 6435dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 6445dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 6455dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 6465dc62b1bSWANG Cong goto out_close; 6475dc62b1bSWANG Cong } 6485dc62b1bSWANG Cong if (err) 6495dc62b1bSWANG Cong return fd; 6505dc62b1bSWANG Cong 6515dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 6525dc62b1bSWANG Cong file); 6535dc62b1bSWANG Cong 6545dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 6555dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 6565dc62b1bSWANG Cong mtime)) { 6575dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 6585dc62b1bSWANG Cong *backing_file_out); 6595dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 6605dc62b1bSWANG Cong sectorsize, align, &size); 6615dc62b1bSWANG Cong if (err) { 6625dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 6635dc62b1bSWANG Cong goto out_close; 6645dc62b1bSWANG Cong } 6655dc62b1bSWANG Cong } else { 6665dc62b1bSWANG Cong *backing_file_out = backing_file; 6675dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 6685dc62b1bSWANG Cong if (err) 6695dc62b1bSWANG Cong goto out_close; 6705dc62b1bSWANG Cong } 6715dc62b1bSWANG Cong 6725dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 6735dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 6745dc62b1bSWANG Cong 6755dc62b1bSWANG Cong return fd; 6765dc62b1bSWANG Cong out_close: 6775dc62b1bSWANG Cong os_close_file(fd); 6785dc62b1bSWANG Cong return err; 6795dc62b1bSWANG Cong } 6805dc62b1bSWANG Cong 6815dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 6825dc62b1bSWANG Cong struct openflags flags, 6835dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 6845dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 6855dc62b1bSWANG Cong { 6865dc62b1bSWANG Cong int err, fd; 6875dc62b1bSWANG Cong 6885dc62b1bSWANG Cong flags.c = 1; 6895dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 6905dc62b1bSWANG Cong if (fd < 0) { 6915dc62b1bSWANG Cong err = fd; 6925dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 6935dc62b1bSWANG Cong cow_file, -err); 6945dc62b1bSWANG Cong goto out; 6955dc62b1bSWANG Cong } 6965dc62b1bSWANG Cong 6975dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 6985dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 6995dc62b1bSWANG Cong data_offset_out); 7005dc62b1bSWANG Cong if (!err) 7015dc62b1bSWANG Cong return fd; 7025dc62b1bSWANG Cong os_close_file(fd); 7035dc62b1bSWANG Cong out: 7045dc62b1bSWANG Cong return err; 7055dc62b1bSWANG Cong } 7065dc62b1bSWANG Cong 7075f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7081da177e4SLinus Torvalds { 7097d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7107d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7111da177e4SLinus Torvalds return; 7121da177e4SLinus Torvalds 7137d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7147d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7157d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7161da177e4SLinus Torvalds } 7171da177e4SLinus Torvalds 7187d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 7191da177e4SLinus Torvalds { 7201da177e4SLinus Torvalds struct openflags flags; 7211da177e4SLinus Torvalds char **back_ptr; 7221da177e4SLinus Torvalds int err, create_cow, *create_ptr; 7230bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 7241da177e4SLinus Torvalds 7257d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 7261da177e4SLinus Torvalds create_cow = 0; 7277d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 7287d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 7290bf16bffSPaolo 'Blaisorblade' Giarrusso 7300bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 7317d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 7327d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 7336c29256cSJeff Dike create_ptr); 7341da177e4SLinus Torvalds 7350bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 7360bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 7377d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags, 1 << 9, PAGE_SIZE, 7387d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 7397d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 7407d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 7410bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 7421da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 7437d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 7441da177e4SLinus Torvalds } 7451da177e4SLinus Torvalds } 7461da177e4SLinus Torvalds 7470bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 7487d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 7490bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 7500bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 7511da177e4SLinus Torvalds } 7520bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 7531da177e4SLinus Torvalds 7547d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 755086fa5ffSMartin K. Petersen blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); 756f4768ffdSJeff Dike 7571da177e4SLinus Torvalds err = -ENOMEM; 758da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 7597d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 7601da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 7611da177e4SLinus Torvalds goto error; 7621da177e4SLinus Torvalds } 7631da177e4SLinus Torvalds flush_tlb_kernel_vm(); 7641da177e4SLinus Torvalds 7657d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 7667d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 7677d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 7681da177e4SLinus Torvalds if(err < 0) 7691da177e4SLinus Torvalds goto error; 7701da177e4SLinus Torvalds 7717d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 7721da177e4SLinus Torvalds flags.w = 0; 7737d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 7746c29256cSJeff Dike NULL, NULL, NULL, NULL); 7751da177e4SLinus Torvalds if(err < 0) goto error; 7767d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 7771da177e4SLinus Torvalds } 778dc764e50SJeff Dike return 0; 7791da177e4SLinus Torvalds error: 7807d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 781dc764e50SJeff Dike return err; 7821da177e4SLinus Torvalds } 7831da177e4SLinus Torvalds 7842e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 7852e3f5251SJeff Dike { 7868691b97bSGreg Kroah-Hartman struct ubd *ubd_dev = dev_get_drvdata(dev); 7872e3f5251SJeff Dike 7882e3f5251SJeff Dike blk_cleanup_queue(ubd_dev->queue); 7892e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 7902e3f5251SJeff Dike } 7912e3f5251SJeff Dike 7925f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 7931da177e4SLinus Torvalds struct gendisk **disk_out) 7941da177e4SLinus Torvalds { 7951da177e4SLinus Torvalds struct gendisk *disk; 7961da177e4SLinus Torvalds 7971da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 7981da177e4SLinus Torvalds if(disk == NULL) 799dc764e50SJeff Dike return -ENOMEM; 8001da177e4SLinus Torvalds 8011da177e4SLinus Torvalds disk->major = major; 8021da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 8031da177e4SLinus Torvalds disk->fops = &ubd_blops; 8041da177e4SLinus Torvalds set_capacity(disk, size / 512); 805792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) 8061da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 807ce7b0f46SGreg Kroah-Hartman else 8081da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 8091da177e4SLinus Torvalds 8101da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 811792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) { 8127d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 8137d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 8142e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 8158691b97bSGreg Kroah-Hartman dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); 8167d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 8177d314e34SPaolo 'Blaisorblade' Giarrusso disk->driverfs_dev = &ubd_devs[unit].pdev.dev; 8181da177e4SLinus Torvalds } 8191da177e4SLinus Torvalds 8207d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 82162f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 8221da177e4SLinus Torvalds add_disk(disk); 8231da177e4SLinus Torvalds 8241da177e4SLinus Torvalds *disk_out = disk; 8251da177e4SLinus Torvalds return 0; 8261da177e4SLinus Torvalds } 8271da177e4SLinus Torvalds 8281da177e4SLinus Torvalds #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) 8291da177e4SLinus Torvalds 830f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 8311da177e4SLinus Torvalds { 8327d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 833f28169d2SJeff Dike int err = 0; 8341da177e4SLinus Torvalds 8357d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 836ec7cf783SJeff Dike goto out; 8371da177e4SLinus Torvalds 8387d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 839f28169d2SJeff Dike if(err < 0){ 840f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 84180c13749SJeff Dike goto out; 842f28169d2SJeff Dike } 8431da177e4SLinus Torvalds 8447d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 8451da177e4SLinus Torvalds 846a0044bdfSJeff Dike INIT_LIST_HEAD(&ubd_dev->restart); 8474f40c055SWANG Cong sg_init_table(ubd_dev->sg, MAX_SG); 848a0044bdfSJeff Dike 84962f96cb0SJeff Dike err = -ENOMEM; 85062f96cb0SJeff Dike ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); 85162f96cb0SJeff Dike if (ubd_dev->queue == NULL) { 85262f96cb0SJeff Dike *error_out = "Failed to initialize device queue"; 85380c13749SJeff Dike goto out; 85462f96cb0SJeff Dike } 85562f96cb0SJeff Dike ubd_dev->queue->queuedata = ubd_dev; 85662f96cb0SJeff Dike 8578a78362cSMartin K. Petersen blk_queue_max_segments(ubd_dev->queue, MAX_SG); 858792dd4fcSChristoph Hellwig err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); 85962f96cb0SJeff Dike if(err){ 86062f96cb0SJeff Dike *error_out = "Failed to register device"; 86162f96cb0SJeff Dike goto out_cleanup; 86262f96cb0SJeff Dike } 8631da177e4SLinus Torvalds 864792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) 8655f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 8661da177e4SLinus Torvalds &fake_gendisk[n]); 8671da177e4SLinus Torvalds 86883380cc1SJeff Dike /* 86983380cc1SJeff Dike * Perhaps this should also be under the "if (fake_major)" above 87083380cc1SJeff Dike * using the fake_disk->disk_name 87183380cc1SJeff Dike */ 8721da177e4SLinus Torvalds if (fake_ide) 8731da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 8741da177e4SLinus Torvalds 875ec7cf783SJeff Dike err = 0; 876ec7cf783SJeff Dike out: 877ec7cf783SJeff Dike return err; 87862f96cb0SJeff Dike 87962f96cb0SJeff Dike out_cleanup: 88062f96cb0SJeff Dike blk_cleanup_queue(ubd_dev->queue); 88162f96cb0SJeff Dike goto out; 8821da177e4SLinus Torvalds } 8831da177e4SLinus Torvalds 884f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 8851da177e4SLinus Torvalds { 886e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 8871da177e4SLinus Torvalds 888f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 889f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 890f28169d2SJeff Dike * were set. 891f28169d2SJeff Dike */ 892970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 8931da177e4SLinus Torvalds if (str == NULL) { 894f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 895f28169d2SJeff Dike return -ENOMEM; 8961da177e4SLinus Torvalds } 897f28169d2SJeff Dike 898f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 899f28169d2SJeff Dike if (ret) 900e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 901f28169d2SJeff Dike 902e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 903e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 904d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 905e7f6552fSPaolo 'Blaisorblade' Giarrusso } 9061da177e4SLinus Torvalds 907d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 908f28169d2SJeff Dike ret = ubd_add(n, error_out); 909e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 9107d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 911d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 9121da177e4SLinus Torvalds 913e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 914e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 915e7f6552fSPaolo 'Blaisorblade' Giarrusso 916e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 917e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 918e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 9191da177e4SLinus Torvalds } 9201da177e4SLinus Torvalds 9211da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 9221da177e4SLinus Torvalds { 9237d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 9241da177e4SLinus Torvalds int n, len = 0; 9251da177e4SLinus Torvalds 9261da177e4SLinus Torvalds n = parse_unit(&name); 9271da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 9281da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 929dc764e50SJeff Dike return -1; 9301da177e4SLinus Torvalds } 9311da177e4SLinus Torvalds 9327d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 933d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 9341da177e4SLinus Torvalds 9357d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 9361da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 9371da177e4SLinus Torvalds goto out; 9381da177e4SLinus Torvalds } 9391da177e4SLinus Torvalds 9407d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 9411da177e4SLinus Torvalds 9427d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 9431da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 9447d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 9451da177e4SLinus Torvalds } 9461da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 9471da177e4SLinus Torvalds 9481da177e4SLinus Torvalds out: 949d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 950dc764e50SJeff Dike return len; 9511da177e4SLinus Torvalds } 9521da177e4SLinus Torvalds 95329d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 95429d56cfeSJeff Dike { 95529d56cfeSJeff Dike int n; 95629d56cfeSJeff Dike 95729d56cfeSJeff Dike n = parse_unit(str); 95829d56cfeSJeff Dike *start_out = 0; 95929d56cfeSJeff Dike *end_out = MAX_DEV - 1; 96029d56cfeSJeff Dike return n; 96129d56cfeSJeff Dike } 96229d56cfeSJeff Dike 963f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 9641da177e4SLinus Torvalds { 9652e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 9667d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 96729d56cfeSJeff Dike int err = -ENODEV; 9681da177e4SLinus Torvalds 969d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 9701da177e4SLinus Torvalds 9717d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 97229d56cfeSJeff Dike 9737d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 97429d56cfeSJeff Dike goto out; 97529d56cfeSJeff Dike 97629d56cfeSJeff Dike /* you cannot remove a open disk */ 97729d56cfeSJeff Dike err = -EBUSY; 9787d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 97929d56cfeSJeff Dike goto out; 98029d56cfeSJeff Dike 9811da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 982b47d2debSJeff Dike if(disk != NULL){ 983b47d2debSJeff Dike del_gendisk(disk); 984b47d2debSJeff Dike put_disk(disk); 985b47d2debSJeff Dike } 9861da177e4SLinus Torvalds 9871da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 9881da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 9891da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 9901da177e4SLinus Torvalds fake_gendisk[n] = NULL; 9911da177e4SLinus Torvalds } 9921da177e4SLinus Torvalds 9931da177e4SLinus Torvalds err = 0; 9942e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 9951da177e4SLinus Torvalds out: 996d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 99729d56cfeSJeff Dike return err; 9981da177e4SLinus Torvalds } 9991da177e4SLinus Torvalds 1000f28169d2SJeff Dike /* All these are called by mconsole in process context and without 1001b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 1002f28169d2SJeff Dike */ 10031da177e4SLinus Torvalds static struct mc_device ubd_mc = { 100484f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 10051da177e4SLinus Torvalds .name = "ubd", 10061da177e4SLinus Torvalds .config = ubd_config, 10071da177e4SLinus Torvalds .get_config = ubd_get_config, 100829d56cfeSJeff Dike .id = ubd_id, 10091da177e4SLinus Torvalds .remove = ubd_remove, 10101da177e4SLinus Torvalds }; 10111da177e4SLinus Torvalds 1012d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 10131da177e4SLinus Torvalds { 10141da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 10151da177e4SLinus Torvalds return 0; 10161da177e4SLinus Torvalds } 10171da177e4SLinus Torvalds 10181da177e4SLinus Torvalds __initcall(ubd_mc_init); 10191da177e4SLinus Torvalds 1020d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1021d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1022d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1023d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1024b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1025d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1026d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1027b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1028b8831a1dSJeff Dike 1029dc764e50SJeff Dike return 0; 1030d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1031d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1032d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1033d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1034b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 10353ae5eaecSRussell King static struct platform_driver ubd_driver = { 10363ae5eaecSRussell King .driver = { 10371da177e4SLinus Torvalds .name = DRIVER_NAME, 10383ae5eaecSRussell King }, 10391da177e4SLinus Torvalds }; 10401da177e4SLinus Torvalds 1041d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 10421da177e4SLinus Torvalds { 1043f28169d2SJeff Dike char *error; 1044f28169d2SJeff Dike int i, err; 10451da177e4SLinus Torvalds 1046792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 10471da177e4SLinus Torvalds return -1; 10481da177e4SLinus Torvalds 1049792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 10501da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 10511da177e4SLinus Torvalds 10521da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 10531da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 10541da177e4SLinus Torvalds return -1; 10551da177e4SLinus Torvalds } 10563ae5eaecSRussell King platform_driver_register(&ubd_driver); 1057b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1058f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1059f28169d2SJeff Dike err = ubd_add(i, &error); 1060f28169d2SJeff Dike if(err) 1061f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1062f28169d2SJeff Dike "%s\n", i, error); 1063f28169d2SJeff Dike } 1064b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 10651da177e4SLinus Torvalds return 0; 10661da177e4SLinus Torvalds } 10671da177e4SLinus Torvalds 10681da177e4SLinus Torvalds late_initcall(ubd_init); 10691da177e4SLinus Torvalds 1070d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 107191acb21fSJeff Dike unsigned long stack; 107291acb21fSJeff Dike int err; 107391acb21fSJeff Dike 107491acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 107591acb21fSJeff Dike if(global_openflags.s){ 107691acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 107791acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 107891acb21fSJeff Dike * enough. So use anyway the io thread. */ 107991acb21fSJeff Dike } 108091acb21fSJeff Dike stack = alloc_stack(0, 0); 108191acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 108291acb21fSJeff Dike &thread_fd); 108391acb21fSJeff Dike if(io_pid < 0){ 108491acb21fSJeff Dike printk(KERN_ERR 108591acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 108691acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 108791acb21fSJeff Dike io_pid = -1; 1088dc764e50SJeff Dike return 0; 108991acb21fSJeff Dike } 109091acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 10917d314e34SPaolo 'Blaisorblade' Giarrusso IRQF_DISABLED, "ubd", ubd_devs); 109291acb21fSJeff Dike if(err != 0) 109391acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1094f4c57a78SJeff Dike return 0; 109591acb21fSJeff Dike } 109691acb21fSJeff Dike 109791acb21fSJeff Dike device_initcall(ubd_driver_init); 109891acb21fSJeff Dike 1099a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 11001da177e4SLinus Torvalds { 1101a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 11027d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 11031da177e4SLinus Torvalds int err = 0; 11041da177e4SLinus Torvalds 11059a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 11067d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 11077d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 11081da177e4SLinus Torvalds if(err){ 11091da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 11107d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 11111da177e4SLinus Torvalds goto out; 11121da177e4SLinus Torvalds } 11131da177e4SLinus Torvalds } 11147d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 11157d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 11162c49be99SPaolo 'Blaisorblade' Giarrusso 11172c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 11182c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1119a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 11205f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 11211da177e4SLinus Torvalds err = -EROFS; 11222c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 11231da177e4SLinus Torvalds out: 11249a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 1125dc764e50SJeff Dike return err; 11261da177e4SLinus Torvalds } 11271da177e4SLinus Torvalds 1128a625c998SAl Viro static int ubd_release(struct gendisk *disk, fmode_t mode) 11291da177e4SLinus Torvalds { 11307d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 11311da177e4SLinus Torvalds 11329a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 11337d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 11345f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 11359a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 1136dc764e50SJeff Dike return 0; 11371da177e4SLinus Torvalds } 11381da177e4SLinus Torvalds 113991acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 114091acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 114191acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 114291acb21fSJeff Dike __u64 bitmap_len) 11431da177e4SLinus Torvalds { 114491acb21fSJeff Dike __u64 sector = io_offset >> 9; 114591acb21fSJeff Dike int i, update_bitmap = 0; 11461da177e4SLinus Torvalds 114791acb21fSJeff Dike for(i = 0; i < length >> 9; i++){ 114891acb21fSJeff Dike if(cow_mask != NULL) 114991acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 115091acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 115109ace81cSJeff Dike continue; 11521da177e4SLinus Torvalds 115391acb21fSJeff Dike update_bitmap = 1; 115491acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 11551da177e4SLinus Torvalds } 115691acb21fSJeff Dike 115791acb21fSJeff Dike if(!update_bitmap) 115891acb21fSJeff Dike return; 115991acb21fSJeff Dike 116091acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 116191acb21fSJeff Dike 116291acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 116391acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 116491acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 116591acb21fSJeff Dike * for the original diagnosis. 116691acb21fSJeff Dike */ 11676d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 11686d074242SJiri Olsa sizeof(unsigned long)) - 1)) 116991acb21fSJeff Dike (*cow_offset)--; 117091acb21fSJeff Dike 117191acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 117291acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 117391acb21fSJeff Dike 117491acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 117591acb21fSJeff Dike *cow_offset += bitmap_offset; 117691acb21fSJeff Dike } 117791acb21fSJeff Dike 117891acb21fSJeff Dike static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, 117991acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 118091acb21fSJeff Dike { 118191acb21fSJeff Dike __u64 sector = req->offset >> 9; 118291acb21fSJeff Dike int i; 118391acb21fSJeff Dike 118491acb21fSJeff Dike if(req->length > (sizeof(req->sector_mask) * 8) << 9) 118591acb21fSJeff Dike panic("Operation too long"); 118691acb21fSJeff Dike 118791acb21fSJeff Dike if(req->op == UBD_READ) { 118891acb21fSJeff Dike for(i = 0; i < req->length >> 9; i++){ 118991acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 119091acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 119191acb21fSJeff Dike &req->sector_mask); 119291acb21fSJeff Dike } 119391acb21fSJeff Dike } 119491acb21fSJeff Dike else cowify_bitmap(req->offset, req->length, &req->sector_mask, 119591acb21fSJeff Dike &req->cow_offset, bitmap, bitmap_offset, 119691acb21fSJeff Dike req->bitmap_words, bitmap_len); 11971da177e4SLinus Torvalds } 11981da177e4SLinus Torvalds 119962f96cb0SJeff Dike /* Called with dev->lock held */ 1200a0044bdfSJeff Dike static void prepare_request(struct request *req, struct io_thread_req *io_req, 1201a0044bdfSJeff Dike unsigned long long offset, int page_offset, 1202a0044bdfSJeff Dike int len, struct page *page) 12031da177e4SLinus Torvalds { 12041da177e4SLinus Torvalds struct gendisk *disk = req->rq_disk; 12057d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 120691acb21fSJeff Dike 120762f96cb0SJeff Dike io_req->req = req; 1208a0044bdfSJeff Dike io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : 1209a0044bdfSJeff Dike ubd_dev->fd; 12107d314e34SPaolo 'Blaisorblade' Giarrusso io_req->fds[1] = ubd_dev->fd; 121191acb21fSJeff Dike io_req->cow_offset = -1; 12121da177e4SLinus Torvalds io_req->offset = offset; 12131da177e4SLinus Torvalds io_req->length = len; 12141da177e4SLinus Torvalds io_req->error = 0; 121591acb21fSJeff Dike io_req->sector_mask = 0; 121691acb21fSJeff Dike 121791acb21fSJeff Dike io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; 12181da177e4SLinus Torvalds io_req->offsets[0] = 0; 12197d314e34SPaolo 'Blaisorblade' Giarrusso io_req->offsets[1] = ubd_dev->cow.data_offset; 1220a0044bdfSJeff Dike io_req->buffer = page_address(page) + page_offset; 12211da177e4SLinus Torvalds io_req->sectorsize = 1 << 9; 12221da177e4SLinus Torvalds 12237d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL) 1224a0044bdfSJeff Dike cowify_req(io_req, ubd_dev->cow.bitmap, 1225a0044bdfSJeff Dike ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); 122691acb21fSJeff Dike 12271da177e4SLinus Torvalds } 12281da177e4SLinus Torvalds 122962f96cb0SJeff Dike /* Called with dev->lock held */ 1230165125e1SJens Axboe static void do_ubd_request(struct request_queue *q) 12311da177e4SLinus Torvalds { 12322adcec21SJeff Dike struct io_thread_req *io_req; 12331da177e4SLinus Torvalds struct request *req; 1234f81f2f7cSTejun Heo int n; 12351da177e4SLinus Torvalds 1236a0044bdfSJeff Dike while(1){ 12372a9529a0SJeff Dike struct ubd *dev = q->queuedata; 1238a0044bdfSJeff Dike if(dev->end_sg == 0){ 12399934c8c0STejun Heo struct request *req = blk_fetch_request(q); 1240a0044bdfSJeff Dike if(req == NULL) 124191acb21fSJeff Dike return; 1242a0044bdfSJeff Dike 1243a0044bdfSJeff Dike dev->request = req; 124447526903STejun Heo dev->rq_pos = blk_rq_pos(req); 1245a0044bdfSJeff Dike dev->start_sg = 0; 1246a0044bdfSJeff Dike dev->end_sg = blk_rq_map_sg(q, req, dev->sg); 1247a0044bdfSJeff Dike } 1248a0044bdfSJeff Dike 1249a0044bdfSJeff Dike req = dev->request; 1250a0044bdfSJeff Dike while(dev->start_sg < dev->end_sg){ 1251a0044bdfSJeff Dike struct scatterlist *sg = &dev->sg[dev->start_sg]; 1252a0044bdfSJeff Dike 12532adcec21SJeff Dike io_req = kmalloc(sizeof(struct io_thread_req), 1254990c5587SPeter Zijlstra GFP_ATOMIC); 12552adcec21SJeff Dike if(io_req == NULL){ 12562adcec21SJeff Dike if(list_empty(&dev->restart)) 12572adcec21SJeff Dike list_add(&dev->restart, &restart); 12582adcec21SJeff Dike return; 12592adcec21SJeff Dike } 12602adcec21SJeff Dike prepare_request(req, io_req, 126147526903STejun Heo (unsigned long long)dev->rq_pos << 9, 126245711f1aSJens Axboe sg->offset, sg->length, sg_page(sg)); 1263a0044bdfSJeff Dike 1264a6ea4cceSJeff Dike n = os_write_file(thread_fd, &io_req, 12652adcec21SJeff Dike sizeof(struct io_thread_req *)); 12662adcec21SJeff Dike if(n != sizeof(struct io_thread_req *)){ 1267a0044bdfSJeff Dike if(n != -EAGAIN) 126891acb21fSJeff Dike printk("write to io thread failed, " 126991acb21fSJeff Dike "errno = %d\n", -n); 1270a0044bdfSJeff Dike else if(list_empty(&dev->restart)) 1271a0044bdfSJeff Dike list_add(&dev->restart, &restart); 127212429bf9SMiklos Szeredi kfree(io_req); 1273a0044bdfSJeff Dike return; 127491acb21fSJeff Dike } 1275a0044bdfSJeff Dike 127647526903STejun Heo dev->rq_pos += sg->length >> 9; 1277a0044bdfSJeff Dike dev->start_sg++; 1278a0044bdfSJeff Dike } 1279a0044bdfSJeff Dike dev->end_sg = 0; 1280a0044bdfSJeff Dike dev->request = NULL; 128191acb21fSJeff Dike } 12821da177e4SLinus Torvalds } 12831da177e4SLinus Torvalds 1284a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1285a885c8c4SChristoph Hellwig { 12867d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1287a885c8c4SChristoph Hellwig 1288a885c8c4SChristoph Hellwig geo->heads = 128; 1289a885c8c4SChristoph Hellwig geo->sectors = 32; 12907d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1291a885c8c4SChristoph Hellwig return 0; 1292a885c8c4SChristoph Hellwig } 1293a885c8c4SChristoph Hellwig 1294a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 12951da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 12961da177e4SLinus Torvalds { 1297a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 129873855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 12991da177e4SLinus Torvalds 13001da177e4SLinus Torvalds switch (cmd) { 13011da177e4SLinus Torvalds struct cdrom_volctrl volume; 13021da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 130373855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 130473855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 130573855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 130673855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 13071da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 13081da177e4SLinus Torvalds sizeof(ubd_id))) 1309dc764e50SJeff Dike return -EFAULT; 1310dc764e50SJeff Dike return 0; 13111da177e4SLinus Torvalds 13121da177e4SLinus Torvalds case CDROMVOLREAD: 13131da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1314dc764e50SJeff Dike return -EFAULT; 13151da177e4SLinus Torvalds volume.channel0 = 255; 13161da177e4SLinus Torvalds volume.channel1 = 255; 13171da177e4SLinus Torvalds volume.channel2 = 255; 13181da177e4SLinus Torvalds volume.channel3 = 255; 13191da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1320dc764e50SJeff Dike return -EFAULT; 1321dc764e50SJeff Dike return 0; 13221da177e4SLinus Torvalds } 1323dc764e50SJeff Dike return -EINVAL; 13241da177e4SLinus Torvalds } 13251da177e4SLinus Torvalds 132691acb21fSJeff Dike static int update_bitmap(struct io_thread_req *req) 13271da177e4SLinus Torvalds { 132891acb21fSJeff Dike int n; 132991acb21fSJeff Dike 133091acb21fSJeff Dike if(req->cow_offset == -1) 1331dc764e50SJeff Dike return 0; 133291acb21fSJeff Dike 133391acb21fSJeff Dike n = os_seek_file(req->fds[1], req->cow_offset); 133491acb21fSJeff Dike if(n < 0){ 133591acb21fSJeff Dike printk("do_io - bitmap lseek failed : err = %d\n", -n); 1336dc764e50SJeff Dike return 1; 133791acb21fSJeff Dike } 133891acb21fSJeff Dike 1339a6ea4cceSJeff Dike n = os_write_file(req->fds[1], &req->bitmap_words, 134091acb21fSJeff Dike sizeof(req->bitmap_words)); 134191acb21fSJeff Dike if(n != sizeof(req->bitmap_words)){ 134291acb21fSJeff Dike printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, 134391acb21fSJeff Dike req->fds[1]); 1344dc764e50SJeff Dike return 1; 134591acb21fSJeff Dike } 134691acb21fSJeff Dike 1347dc764e50SJeff Dike return 0; 134891acb21fSJeff Dike } 134991acb21fSJeff Dike 13505dc62b1bSWANG Cong static void do_io(struct io_thread_req *req) 135191acb21fSJeff Dike { 13521da177e4SLinus Torvalds char *buf; 135391acb21fSJeff Dike unsigned long len; 135491acb21fSJeff Dike int n, nsectors, start, end, bit; 135591acb21fSJeff Dike int err; 13561da177e4SLinus Torvalds __u64 off; 13571da177e4SLinus Torvalds 13581da177e4SLinus Torvalds nsectors = req->length / req->sectorsize; 13591da177e4SLinus Torvalds start = 0; 13601da177e4SLinus Torvalds do { 136191acb21fSJeff Dike bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); 13621da177e4SLinus Torvalds end = start; 13631da177e4SLinus Torvalds while((end < nsectors) && 136491acb21fSJeff Dike (ubd_test_bit(end, (unsigned char *) 136591acb21fSJeff Dike &req->sector_mask) == bit)) 13661da177e4SLinus Torvalds end++; 13671da177e4SLinus Torvalds 136891acb21fSJeff Dike off = req->offset + req->offsets[bit] + 13691da177e4SLinus Torvalds start * req->sectorsize; 13701da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 13711da177e4SLinus Torvalds buf = &req->buffer[start * req->sectorsize]; 13721da177e4SLinus Torvalds 137391acb21fSJeff Dike err = os_seek_file(req->fds[bit], off); 137491acb21fSJeff Dike if(err < 0){ 137591acb21fSJeff Dike printk("do_io - lseek failed : err = %d\n", -err); 13761da177e4SLinus Torvalds req->error = 1; 13771da177e4SLinus Torvalds return; 13781da177e4SLinus Torvalds } 137991acb21fSJeff Dike if(req->op == UBD_READ){ 138091acb21fSJeff Dike n = 0; 138191acb21fSJeff Dike do { 138291acb21fSJeff Dike buf = &buf[n]; 138391acb21fSJeff Dike len -= n; 1384a6ea4cceSJeff Dike n = os_read_file(req->fds[bit], buf, len); 138591acb21fSJeff Dike if (n < 0) { 138691acb21fSJeff Dike printk("do_io - read failed, err = %d " 138791acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 13881da177e4SLinus Torvalds req->error = 1; 13891da177e4SLinus Torvalds return; 13901da177e4SLinus Torvalds } 139191acb21fSJeff Dike } while((n < len) && (n != 0)); 139291acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 139391acb21fSJeff Dike } else { 1394a6ea4cceSJeff Dike n = os_write_file(req->fds[bit], buf, len); 139591acb21fSJeff Dike if(n != len){ 139691acb21fSJeff Dike printk("do_io - write failed err = %d " 139791acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 139891acb21fSJeff Dike req->error = 1; 139991acb21fSJeff Dike return; 140091acb21fSJeff Dike } 140191acb21fSJeff Dike } 14021da177e4SLinus Torvalds 14031da177e4SLinus Torvalds start = end; 14041da177e4SLinus Torvalds } while(start < nsectors); 140591acb21fSJeff Dike 140691acb21fSJeff Dike req->error = update_bitmap(req); 14071da177e4SLinus Torvalds } 140891acb21fSJeff Dike 140991acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 141091acb21fSJeff Dike * from ubd_init, which is an initcall. 141191acb21fSJeff Dike */ 141291acb21fSJeff Dike int kernel_fd = -1; 141391acb21fSJeff Dike 1414d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1415d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 141691acb21fSJeff Dike 141791acb21fSJeff Dike int io_thread(void *arg) 141891acb21fSJeff Dike { 14192adcec21SJeff Dike struct io_thread_req *req; 142091acb21fSJeff Dike int n; 142191acb21fSJeff Dike 142291acb21fSJeff Dike ignore_sigwinch_sig(); 142391acb21fSJeff Dike while(1){ 1424a6ea4cceSJeff Dike n = os_read_file(kernel_fd, &req, 14252adcec21SJeff Dike sizeof(struct io_thread_req *)); 14262adcec21SJeff Dike if(n != sizeof(struct io_thread_req *)){ 142791acb21fSJeff Dike if(n < 0) 142891acb21fSJeff Dike printk("io_thread - read failed, fd = %d, " 142991acb21fSJeff Dike "err = %d\n", kernel_fd, -n); 143091acb21fSJeff Dike else { 143191acb21fSJeff Dike printk("io_thread - short read, fd = %d, " 143291acb21fSJeff Dike "length = %d\n", kernel_fd, n); 143391acb21fSJeff Dike } 143491acb21fSJeff Dike continue; 143591acb21fSJeff Dike } 143691acb21fSJeff Dike io_count++; 14372adcec21SJeff Dike do_io(req); 1438a6ea4cceSJeff Dike n = os_write_file(kernel_fd, &req, 14392adcec21SJeff Dike sizeof(struct io_thread_req *)); 14402adcec21SJeff Dike if(n != sizeof(struct io_thread_req *)) 144191acb21fSJeff Dike printk("io_thread - write failed, fd = %d, err = %d\n", 144291acb21fSJeff Dike kernel_fd, -n); 144391acb21fSJeff Dike } 144491acb21fSJeff Dike 14451b57e9c2SJeff Dike return 0; 14461b57e9c2SJeff Dike } 1447