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" 301da177e4SLinus Torvalds #include "linux/ctype.h" 311da177e4SLinus Torvalds #include "linux/capability.h" 321da177e4SLinus Torvalds #include "linux/mm.h" 331da177e4SLinus Torvalds #include "linux/vmalloc.h" 341da177e4SLinus Torvalds #include "linux/blkpg.h" 351da177e4SLinus Torvalds #include "linux/genhd.h" 361da177e4SLinus Torvalds #include "linux/spinlock.h" 37d052d1beSRussell King #include "linux/platform_device.h" 3823464ffaSWANG Cong #include "linux/scatterlist.h" 391da177e4SLinus Torvalds #include "asm/segment.h" 401da177e4SLinus Torvalds #include "asm/uaccess.h" 411da177e4SLinus Torvalds #include "asm/irq.h" 421da177e4SLinus Torvalds #include "asm/types.h" 431da177e4SLinus Torvalds #include "asm/tlbflush.h" 441da177e4SLinus Torvalds #include "mem_user.h" 451da177e4SLinus Torvalds #include "kern_util.h" 461da177e4SLinus Torvalds #include "kern.h" 471da177e4SLinus Torvalds #include "mconsole_kern.h" 481da177e4SLinus Torvalds #include "init.h" 491da177e4SLinus Torvalds #include "irq_user.h" 501da177e4SLinus Torvalds #include "irq_kern.h" 511da177e4SLinus Torvalds #include "ubd_user.h" 521da177e4SLinus Torvalds #include "os.h" 531da177e4SLinus Torvalds #include "mem.h" 541da177e4SLinus Torvalds #include "mem_kern.h" 551da177e4SLinus Torvalds #include "cow.h" 561da177e4SLinus Torvalds 577b9014c1SJeff Dike enum ubd_req { UBD_READ, UBD_WRITE }; 581da177e4SLinus Torvalds 591da177e4SLinus Torvalds struct io_thread_req { 6062f96cb0SJeff Dike struct request *req; 6191acb21fSJeff Dike enum ubd_req op; 621da177e4SLinus Torvalds int fds[2]; 631da177e4SLinus Torvalds unsigned long offsets[2]; 641da177e4SLinus Torvalds unsigned long long offset; 651da177e4SLinus Torvalds unsigned long length; 661da177e4SLinus Torvalds char *buffer; 671da177e4SLinus Torvalds int sectorsize; 6891acb21fSJeff Dike unsigned long sector_mask; 6991acb21fSJeff Dike unsigned long long cow_offset; 7091acb21fSJeff Dike unsigned long bitmap_words[2]; 711da177e4SLinus Torvalds int error; 721da177e4SLinus Torvalds }; 731da177e4SLinus Torvalds 7491acb21fSJeff Dike static inline int ubd_test_bit(__u64 bit, unsigned char *data) 751da177e4SLinus Torvalds { 761da177e4SLinus Torvalds __u64 n; 771da177e4SLinus Torvalds int bits, off; 781da177e4SLinus Torvalds 7991acb21fSJeff Dike bits = sizeof(data[0]) * 8; 801da177e4SLinus Torvalds n = bit / bits; 811da177e4SLinus Torvalds off = bit % bits; 82dc764e50SJeff Dike return (data[n] & (1 << off)) != 0; 831da177e4SLinus Torvalds } 841da177e4SLinus Torvalds 8591acb21fSJeff Dike static inline void ubd_set_bit(__u64 bit, unsigned char *data) 861da177e4SLinus Torvalds { 871da177e4SLinus Torvalds __u64 n; 881da177e4SLinus Torvalds int bits, off; 891da177e4SLinus Torvalds 9091acb21fSJeff Dike bits = sizeof(data[0]) * 8; 911da177e4SLinus Torvalds n = bit / bits; 921da177e4SLinus Torvalds off = bit % bits; 9391acb21fSJeff Dike data[n] |= (1 << off); 941da177e4SLinus Torvalds } 951da177e4SLinus Torvalds /*End stuff from ubd_user.h*/ 961da177e4SLinus Torvalds 971da177e4SLinus Torvalds #define DRIVER_NAME "uml-blkdev" 981da177e4SLinus Torvalds 99d7fb2c38SPaolo 'Blaisorblade' Giarrusso static DEFINE_MUTEX(ubd_lock); 1001da177e4SLinus Torvalds 101a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode); 102a625c998SAl Viro static int ubd_release(struct gendisk *disk, fmode_t mode); 103a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 1041da177e4SLinus Torvalds unsigned int cmd, unsigned long arg); 105a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); 1061da177e4SLinus Torvalds 10797d88ac8SPaolo 'Blaisorblade' Giarrusso #define MAX_DEV (16) 1081da177e4SLinus Torvalds 1091da177e4SLinus Torvalds static struct block_device_operations ubd_blops = { 1101da177e4SLinus Torvalds .owner = THIS_MODULE, 111a625c998SAl Viro .open = ubd_open, 112a625c998SAl Viro .release = ubd_release, 113a625c998SAl Viro .ioctl = ubd_ioctl, 114a885c8c4SChristoph Hellwig .getgeo = ubd_getgeo, 1151da177e4SLinus Torvalds }; 1161da177e4SLinus Torvalds 1171da177e4SLinus Torvalds /* Protected by ubd_lock */ 118792dd4fcSChristoph Hellwig static int fake_major = UBD_MAJOR; 1191da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1201da177e4SLinus Torvalds static struct gendisk *fake_gendisk[MAX_DEV]; 1211da177e4SLinus Torvalds 1221da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1231da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1241da177e4SLinus Torvalds .cl = 1 }) 1251da177e4SLinus Torvalds #else 1261da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1271da177e4SLinus Torvalds .cl = 1 }) 1281da177e4SLinus Torvalds #endif 1291da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1301da177e4SLinus Torvalds 1311da177e4SLinus Torvalds struct cow { 1322a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file name */ 1331da177e4SLinus Torvalds char *file; 1342a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file fd */ 1351da177e4SLinus Torvalds int fd; 1361da177e4SLinus Torvalds unsigned long *bitmap; 1371da177e4SLinus Torvalds unsigned long bitmap_len; 1381da177e4SLinus Torvalds int bitmap_offset; 1391da177e4SLinus Torvalds int data_offset; 1401da177e4SLinus Torvalds }; 1411da177e4SLinus Torvalds 142a0044bdfSJeff Dike #define MAX_SG 64 143a0044bdfSJeff Dike 1441da177e4SLinus Torvalds struct ubd { 145a0044bdfSJeff Dike struct list_head restart; 1462a9d32f6SPaolo 'Blaisorblade' Giarrusso /* name (and fd, below) of the file opened for writing, either the 1472a9d32f6SPaolo 'Blaisorblade' Giarrusso * backing or the cow file. */ 1481da177e4SLinus Torvalds char *file; 1491da177e4SLinus Torvalds int count; 1501da177e4SLinus Torvalds int fd; 1511da177e4SLinus Torvalds __u64 size; 1521da177e4SLinus Torvalds struct openflags boot_openflags; 1531da177e4SLinus Torvalds struct openflags openflags; 15484e945e3SPaolo 'Blaisorblade' Giarrusso unsigned shared:1; 15584e945e3SPaolo 'Blaisorblade' Giarrusso unsigned no_cow:1; 1561da177e4SLinus Torvalds struct cow cow; 1571da177e4SLinus Torvalds struct platform_device pdev; 15862f96cb0SJeff Dike struct request_queue *queue; 15962f96cb0SJeff Dike spinlock_t lock; 160a0044bdfSJeff Dike struct scatterlist sg[MAX_SG]; 161a0044bdfSJeff Dike struct request *request; 162a0044bdfSJeff Dike int start_sg, end_sg; 1631da177e4SLinus Torvalds }; 1641da177e4SLinus Torvalds 1651da177e4SLinus Torvalds #define DEFAULT_COW { \ 1661da177e4SLinus Torvalds .file = NULL, \ 1671da177e4SLinus Torvalds .fd = -1, \ 1681da177e4SLinus Torvalds .bitmap = NULL, \ 1691da177e4SLinus Torvalds .bitmap_offset = 0, \ 1701da177e4SLinus Torvalds .data_offset = 0, \ 1711da177e4SLinus Torvalds } 1721da177e4SLinus Torvalds 1731da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1741da177e4SLinus Torvalds .file = NULL, \ 1751da177e4SLinus Torvalds .count = 0, \ 1761da177e4SLinus Torvalds .fd = -1, \ 1771da177e4SLinus Torvalds .size = -1, \ 1781da177e4SLinus Torvalds .boot_openflags = OPEN_FLAGS, \ 1791da177e4SLinus Torvalds .openflags = OPEN_FLAGS, \ 1801da177e4SLinus Torvalds .no_cow = 0, \ 1816c29256cSJeff Dike .shared = 0, \ 1821da177e4SLinus Torvalds .cow = DEFAULT_COW, \ 18362f96cb0SJeff Dike .lock = SPIN_LOCK_UNLOCKED, \ 184a0044bdfSJeff Dike .request = NULL, \ 185a0044bdfSJeff Dike .start_sg = 0, \ 186a0044bdfSJeff Dike .end_sg = 0, \ 1871da177e4SLinus Torvalds } 1881da177e4SLinus Torvalds 189b8831a1dSJeff Dike /* Protected by ubd_lock */ 1905dc62b1bSWANG Cong static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; 1911da177e4SLinus Torvalds 1921da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 1931da177e4SLinus Torvalds static int fake_ide = 0; 1941da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 1951da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 1961da177e4SLinus Torvalds 1971da177e4SLinus Torvalds static void make_proc_ide(void) 1981da177e4SLinus Torvalds { 1991da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 2001da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 2011da177e4SLinus Torvalds } 2021da177e4SLinus Torvalds 2031da177e4SLinus Torvalds static int proc_ide_read_media(char *page, char **start, off_t off, int count, 2041da177e4SLinus Torvalds int *eof, void *data) 2051da177e4SLinus Torvalds { 2061da177e4SLinus Torvalds int len; 2071da177e4SLinus Torvalds 2081da177e4SLinus Torvalds strcpy(page, "disk\n"); 2091da177e4SLinus Torvalds len = strlen("disk\n"); 2101da177e4SLinus Torvalds len -= off; 2111da177e4SLinus Torvalds if (len < count){ 2121da177e4SLinus Torvalds *eof = 1; 2131da177e4SLinus Torvalds if (len <= 0) return 0; 2141da177e4SLinus Torvalds } 2151da177e4SLinus Torvalds else len = count; 2161da177e4SLinus Torvalds *start = page + off; 2171da177e4SLinus Torvalds return len; 2181da177e4SLinus Torvalds } 2191da177e4SLinus Torvalds 220c0a9290eSWANG Cong static void make_ide_entries(const char *dev_name) 2211da177e4SLinus Torvalds { 2221da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2231da177e4SLinus Torvalds char name[64]; 2241da177e4SLinus Torvalds 2251da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2261da177e4SLinus Torvalds 2271da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2281da177e4SLinus Torvalds if(!dir) return; 2291da177e4SLinus Torvalds 2301da177e4SLinus Torvalds ent = create_proc_entry("media", S_IFREG|S_IRUGO, dir); 2311da177e4SLinus Torvalds if(!ent) return; 2321da177e4SLinus Torvalds ent->data = NULL; 2331da177e4SLinus Torvalds ent->read_proc = proc_ide_read_media; 2341da177e4SLinus Torvalds ent->write_proc = NULL; 235c0a9290eSWANG Cong snprintf(name, sizeof(name), "ide0/%s", dev_name); 2361da177e4SLinus Torvalds proc_symlink(dev_name, proc_ide_root, name); 2371da177e4SLinus Torvalds } 2381da177e4SLinus Torvalds 2391da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2401da177e4SLinus Torvalds { 2411da177e4SLinus Torvalds fake_ide = 1; 242dc764e50SJeff Dike return 1; 2431da177e4SLinus Torvalds } 2441da177e4SLinus Torvalds 2451da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2461da177e4SLinus Torvalds 2471da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2481da177e4SLinus Torvalds "fake_ide\n" 2491da177e4SLinus Torvalds " Create ide0 entries that map onto ubd devices.\n\n" 2501da177e4SLinus Torvalds ); 2511da177e4SLinus Torvalds 2521da177e4SLinus Torvalds static int parse_unit(char **ptr) 2531da177e4SLinus Torvalds { 2541da177e4SLinus Torvalds char *str = *ptr, *end; 2551da177e4SLinus Torvalds int n = -1; 2561da177e4SLinus Torvalds 2571da177e4SLinus Torvalds if(isdigit(*str)) { 2581da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2591da177e4SLinus Torvalds if(end == str) 260dc764e50SJeff Dike return -1; 2611da177e4SLinus Torvalds *ptr = end; 2621da177e4SLinus Torvalds } 26397d88ac8SPaolo 'Blaisorblade' Giarrusso else if (('a' <= *str) && (*str <= 'z')) { 2641da177e4SLinus Torvalds n = *str - 'a'; 2651da177e4SLinus Torvalds str++; 2661da177e4SLinus Torvalds *ptr = str; 2671da177e4SLinus Torvalds } 268dc764e50SJeff Dike return n; 2691da177e4SLinus Torvalds } 2701da177e4SLinus Torvalds 271d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* If *index_out == -1 at exit, the passed option was a general one; 272d8d7c28eSPaolo 'Blaisorblade' Giarrusso * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it 273d8d7c28eSPaolo 'Blaisorblade' Giarrusso * should not be freed on exit. 274d8d7c28eSPaolo 'Blaisorblade' Giarrusso */ 275f28169d2SJeff Dike static int ubd_setup_common(char *str, int *index_out, char **error_out) 2761da177e4SLinus Torvalds { 2777d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 2781da177e4SLinus Torvalds struct openflags flags = global_openflags; 2791da177e4SLinus Torvalds char *backing_file; 280b8831a1dSJeff Dike int n, err = 0, i; 2811da177e4SLinus Torvalds 2821da177e4SLinus Torvalds if(index_out) *index_out = -1; 2831da177e4SLinus Torvalds n = *str; 2841da177e4SLinus Torvalds if(n == '='){ 2851da177e4SLinus Torvalds char *end; 2861da177e4SLinus Torvalds int major; 2871da177e4SLinus Torvalds 2881da177e4SLinus Torvalds str++; 2891da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 2901da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 291b8831a1dSJeff Dike goto out1; 2921da177e4SLinus Torvalds } 2931da177e4SLinus Torvalds 294f28169d2SJeff Dike err = -EINVAL; 295b8831a1dSJeff Dike major = simple_strtoul(str, &end, 0); 296b8831a1dSJeff Dike if((*end != '\0') || (end == str)){ 297b8831a1dSJeff Dike *error_out = "Didn't parse major number"; 298b8831a1dSJeff Dike goto out1; 299b8831a1dSJeff Dike } 300b8831a1dSJeff Dike 301d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 302792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 303f28169d2SJeff Dike *error_out = "Can't assign a fake major twice"; 3041da177e4SLinus Torvalds goto out1; 3051da177e4SLinus Torvalds } 3061da177e4SLinus Torvalds 3071da177e4SLinus Torvalds fake_major = major; 3081da177e4SLinus Torvalds 3091da177e4SLinus Torvalds printk(KERN_INFO "Setting extra ubd major number to %d\n", 3101da177e4SLinus Torvalds major); 3111da177e4SLinus Torvalds err = 0; 3121da177e4SLinus Torvalds out1: 313d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 314f28169d2SJeff Dike return err; 3151da177e4SLinus Torvalds } 3161da177e4SLinus Torvalds 3171da177e4SLinus Torvalds n = parse_unit(&str); 3181da177e4SLinus Torvalds if(n < 0){ 319f28169d2SJeff Dike *error_out = "Couldn't parse device number"; 320f28169d2SJeff Dike return -EINVAL; 3211da177e4SLinus Torvalds } 3221da177e4SLinus Torvalds if(n >= MAX_DEV){ 323f28169d2SJeff Dike *error_out = "Device number out of range"; 324f28169d2SJeff Dike return 1; 3251da177e4SLinus Torvalds } 3261da177e4SLinus Torvalds 327f28169d2SJeff Dike err = -EBUSY; 328d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 3291da177e4SLinus Torvalds 3307d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 3317d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file != NULL){ 332f28169d2SJeff Dike *error_out = "Device is already configured"; 3331da177e4SLinus Torvalds goto out; 3341da177e4SLinus Torvalds } 3351da177e4SLinus Torvalds 3361da177e4SLinus Torvalds if (index_out) 3371da177e4SLinus Torvalds *index_out = n; 3381da177e4SLinus Torvalds 339f28169d2SJeff Dike err = -EINVAL; 3406c29256cSJeff Dike for (i = 0; i < sizeof("rscd="); i++) { 3411da177e4SLinus Torvalds switch (*str) { 3421da177e4SLinus Torvalds case 'r': 3431da177e4SLinus Torvalds flags.w = 0; 3441da177e4SLinus Torvalds break; 3451da177e4SLinus Torvalds case 's': 3461da177e4SLinus Torvalds flags.s = 1; 3471da177e4SLinus Torvalds break; 3481da177e4SLinus Torvalds case 'd': 3497d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->no_cow = 1; 3501da177e4SLinus Torvalds break; 3516c29256cSJeff Dike case 'c': 3527d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->shared = 1; 3536c29256cSJeff Dike break; 3541da177e4SLinus Torvalds case '=': 3551da177e4SLinus Torvalds str++; 3561da177e4SLinus Torvalds goto break_loop; 3571da177e4SLinus Torvalds default: 358f28169d2SJeff Dike *error_out = "Expected '=' or flag letter " 359f28169d2SJeff Dike "(r, s, c, or d)"; 3601da177e4SLinus Torvalds goto out; 3611da177e4SLinus Torvalds } 3621da177e4SLinus Torvalds str++; 3631da177e4SLinus Torvalds } 3641da177e4SLinus Torvalds 3651da177e4SLinus Torvalds if (*str == '=') 366f28169d2SJeff Dike *error_out = "Too many flags specified"; 3671da177e4SLinus Torvalds else 368f28169d2SJeff Dike *error_out = "Missing '='"; 3691da177e4SLinus Torvalds goto out; 3701da177e4SLinus Torvalds 3711da177e4SLinus Torvalds break_loop: 3721da177e4SLinus Torvalds backing_file = strchr(str, ','); 3731da177e4SLinus Torvalds 374f28169d2SJeff Dike if (backing_file == NULL) 3751da177e4SLinus Torvalds backing_file = strchr(str, ':'); 3761da177e4SLinus Torvalds 377f28169d2SJeff Dike if(backing_file != NULL){ 378f28169d2SJeff Dike if(ubd_dev->no_cow){ 379f28169d2SJeff Dike *error_out = "Can't specify both 'd' and a cow file"; 380f28169d2SJeff Dike goto out; 381f28169d2SJeff Dike } 3821da177e4SLinus Torvalds else { 3831da177e4SLinus Torvalds *backing_file = '\0'; 3841da177e4SLinus Torvalds backing_file++; 3851da177e4SLinus Torvalds } 3861da177e4SLinus Torvalds } 387f28169d2SJeff Dike err = 0; 3887d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->file = str; 3897d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.file = backing_file; 3907d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->boot_openflags = flags; 3911da177e4SLinus Torvalds out: 392d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 393f28169d2SJeff Dike return err; 3941da177e4SLinus Torvalds } 3951da177e4SLinus Torvalds 3961da177e4SLinus Torvalds static int ubd_setup(char *str) 3971da177e4SLinus Torvalds { 398f28169d2SJeff Dike char *error; 399f28169d2SJeff Dike int err; 400f28169d2SJeff Dike 401f28169d2SJeff Dike err = ubd_setup_common(str, NULL, &error); 402f28169d2SJeff Dike if(err) 403f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize device with \"%s\" : " 404f28169d2SJeff Dike "%s\n", str, error); 405f28169d2SJeff Dike return 1; 4061da177e4SLinus Torvalds } 4071da177e4SLinus Torvalds 4081da177e4SLinus Torvalds __setup("ubd", ubd_setup); 4091da177e4SLinus Torvalds __uml_help(ubd_setup, 4101da177e4SLinus Torvalds "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" 4111da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 4121da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 4131da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 4141da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 4151da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 4161da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 417f28169d2SJeff Dike " When using only one filename, UML will detect whether to treat it like\n" 4181da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 4191da177e4SLinus Torvalds " flag:\n" 4201da177e4SLinus Torvalds " ubd0d=BackingFile\n" 4211da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 4221da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 4231da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 4241da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 4251da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 4261da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 4271da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 42820ede453SJeff Dike " an 's' will cause data to be written to disk on the host immediately.\n" 42920ede453SJeff Dike " 'c' will cause the device to be treated as being shared between multiple\n" 43020ede453SJeff Dike " UMLs and file locking will be turned off - this is appropriate for a\n" 43120ede453SJeff Dike " cluster filesystem and inappropriate at almost all other times.\n\n" 4321da177e4SLinus Torvalds ); 4331da177e4SLinus Torvalds 4348299ca5cSJeff Dike static int udb_setup(char *str) 4351da177e4SLinus Torvalds { 4361da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 4371da177e4SLinus Torvalds "udb TYPO\n", str); 438dc764e50SJeff Dike return 1; 4391da177e4SLinus Torvalds } 4401da177e4SLinus Torvalds 4411da177e4SLinus Torvalds __setup("udb", udb_setup); 4421da177e4SLinus Torvalds __uml_help(udb_setup, 4431da177e4SLinus Torvalds "udb\n" 4440894e27eSJeff Dike " This option is here solely to catch ubd -> udb typos, which can be\n" 4450894e27eSJeff Dike " to impossible to catch visually unless you specifically look for\n" 4460894e27eSJeff Dike " them. The only result of any option starting with 'udb' is an error\n" 4471da177e4SLinus Torvalds " in the boot output.\n\n" 4481da177e4SLinus Torvalds ); 4491da177e4SLinus Torvalds 450165125e1SJens Axboe static void do_ubd_request(struct request_queue * q); 45191acb21fSJeff Dike 45291acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 4535dc62b1bSWANG Cong static int thread_fd = -1; 4541da177e4SLinus Torvalds 4554898b53aSKiyoshi Ueda static void ubd_end_request(struct request *req, int bytes, int error) 4561da177e4SLinus Torvalds { 4574898b53aSKiyoshi Ueda blk_end_request(req, error, bytes); 4581da177e4SLinus Torvalds } 4591da177e4SLinus Torvalds 46033f775eeSPaolo 'Blaisorblade' Giarrusso /* Callable only from interrupt context - otherwise you need to do 46133f775eeSPaolo 'Blaisorblade' Giarrusso * spin_lock_irq()/spin_lock_irqsave() */ 462a0044bdfSJeff Dike static inline void ubd_finish(struct request *req, int bytes) 46309ace81cSJeff Dike { 464a0044bdfSJeff Dike if(bytes < 0){ 4654898b53aSKiyoshi Ueda ubd_end_request(req, 0, -EIO); 466a0044bdfSJeff Dike return; 46709ace81cSJeff Dike } 4684898b53aSKiyoshi Ueda ubd_end_request(req, bytes, 0); 469a0044bdfSJeff Dike } 470a0044bdfSJeff Dike 471a0044bdfSJeff Dike static LIST_HEAD(restart); 47209ace81cSJeff Dike 4732fe30a34SPaolo 'Blaisorblade' Giarrusso /* XXX - move this inside ubd_intr. */ 47462f96cb0SJeff Dike /* Called without dev->lock held, and only in interrupt context. */ 47591acb21fSJeff Dike static void ubd_handler(void) 47691acb21fSJeff Dike { 4772adcec21SJeff Dike struct io_thread_req *req; 47862f96cb0SJeff Dike struct request *rq; 479a0044bdfSJeff Dike struct ubd *ubd; 480a0044bdfSJeff Dike struct list_head *list, *next_ele; 481a0044bdfSJeff Dike unsigned long flags; 48291acb21fSJeff Dike int n; 48309ace81cSJeff Dike 484a0044bdfSJeff Dike while(1){ 485a6ea4cceSJeff Dike n = os_read_file(thread_fd, &req, 4862adcec21SJeff Dike sizeof(struct io_thread_req *)); 48791acb21fSJeff Dike if(n != sizeof(req)){ 488a0044bdfSJeff Dike if(n == -EAGAIN) 489a0044bdfSJeff Dike break; 490a0044bdfSJeff Dike printk(KERN_ERR "spurious interrupt in ubd_handler, " 491a0044bdfSJeff Dike "err = %d\n", -n); 49291acb21fSJeff Dike return; 49391acb21fSJeff Dike } 49409ace81cSJeff Dike 4952adcec21SJeff Dike rq = req->req; 4962adcec21SJeff Dike rq->nr_sectors -= req->length >> 9; 497a0044bdfSJeff Dike if(rq->nr_sectors == 0) 498a0044bdfSJeff Dike ubd_finish(rq, rq->hard_nr_sectors << 9); 4992adcec21SJeff Dike kfree(req); 500a0044bdfSJeff Dike } 50191acb21fSJeff Dike reactivate_fd(thread_fd, UBD_IRQ); 502a0044bdfSJeff Dike 503a0044bdfSJeff Dike list_for_each_safe(list, next_ele, &restart){ 504a0044bdfSJeff Dike ubd = container_of(list, struct ubd, restart); 505a0044bdfSJeff Dike list_del_init(&ubd->restart); 506a0044bdfSJeff Dike spin_lock_irqsave(&ubd->lock, flags); 507a0044bdfSJeff Dike do_ubd_request(ubd->queue); 508a0044bdfSJeff Dike spin_unlock_irqrestore(&ubd->lock, flags); 509a0044bdfSJeff Dike } 51091acb21fSJeff Dike } 51109ace81cSJeff Dike 5127bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 5131da177e4SLinus Torvalds { 51491acb21fSJeff Dike ubd_handler(); 515dc764e50SJeff Dike return IRQ_HANDLED; 5161da177e4SLinus Torvalds } 5171da177e4SLinus Torvalds 51891acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 51991acb21fSJeff Dike static int io_pid = -1; 52091acb21fSJeff Dike 5215dc62b1bSWANG Cong static void kill_io_thread(void) 52291acb21fSJeff Dike { 52391acb21fSJeff Dike if(io_pid != -1) 52491acb21fSJeff Dike os_kill_process(io_pid, 1); 52591acb21fSJeff Dike } 52691acb21fSJeff Dike 52791acb21fSJeff Dike __uml_exitcall(kill_io_thread); 52891acb21fSJeff Dike 529d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5301da177e4SLinus Torvalds { 5311da177e4SLinus Torvalds char *file; 5321da177e4SLinus Torvalds 5337d314e34SPaolo 'Blaisorblade' Giarrusso file = ubd_dev->cow.file ? ubd_dev->cow.file : ubd_dev->file; 534dc764e50SJeff Dike return os_file_size(file, size_out); 5351da177e4SLinus Torvalds } 5361da177e4SLinus Torvalds 5375dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 5385dc62b1bSWANG Cong { 5395dc62b1bSWANG Cong int err; 5405dc62b1bSWANG Cong 5415dc62b1bSWANG Cong err = os_seek_file(fd, offset); 5425dc62b1bSWANG Cong if (err < 0) 5435dc62b1bSWANG Cong return err; 5445dc62b1bSWANG Cong 5455dc62b1bSWANG Cong err = os_read_file(fd, buf, len); 5465dc62b1bSWANG Cong if (err < 0) 5475dc62b1bSWANG Cong return err; 5485dc62b1bSWANG Cong 5495dc62b1bSWANG Cong return 0; 5505dc62b1bSWANG Cong } 5515dc62b1bSWANG Cong 5525dc62b1bSWANG Cong static int backing_file_mismatch(char *file, __u64 size, time_t mtime) 5535dc62b1bSWANG Cong { 5545dc62b1bSWANG Cong unsigned long modtime; 5555dc62b1bSWANG Cong unsigned long long actual; 5565dc62b1bSWANG Cong int err; 5575dc62b1bSWANG Cong 5585dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 5595dc62b1bSWANG Cong if (err < 0) { 5605dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 5615dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 5625dc62b1bSWANG Cong return err; 5635dc62b1bSWANG Cong } 5645dc62b1bSWANG Cong 5655dc62b1bSWANG Cong err = os_file_size(file, &actual); 5665dc62b1bSWANG Cong if (err < 0) { 5675dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 5685dc62b1bSWANG Cong "err = %d\n", file, -err); 5695dc62b1bSWANG Cong return err; 5705dc62b1bSWANG Cong } 5715dc62b1bSWANG Cong 5725dc62b1bSWANG Cong if (actual != size) { 5735dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 5745dc62b1bSWANG Cong * the typecast.*/ 5755dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 5765dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 5775dc62b1bSWANG Cong return -EINVAL; 5785dc62b1bSWANG Cong } 5795dc62b1bSWANG Cong if (modtime != mtime) { 5805dc62b1bSWANG Cong printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " 5815dc62b1bSWANG Cong "backing file\n", mtime, modtime); 5825dc62b1bSWANG Cong return -EINVAL; 5835dc62b1bSWANG Cong } 5845dc62b1bSWANG Cong return 0; 5855dc62b1bSWANG Cong } 5865dc62b1bSWANG Cong 5875dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 5885dc62b1bSWANG Cong { 5895dc62b1bSWANG Cong struct uml_stat buf1, buf2; 5905dc62b1bSWANG Cong int err; 5915dc62b1bSWANG Cong 5925dc62b1bSWANG Cong if (from_cmdline == NULL) 5935dc62b1bSWANG Cong return 0; 5945dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 5955dc62b1bSWANG Cong return 0; 5965dc62b1bSWANG Cong 5975dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 5985dc62b1bSWANG Cong if (err < 0) { 5995dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 6005dc62b1bSWANG Cong -err); 6015dc62b1bSWANG Cong return 0; 6025dc62b1bSWANG Cong } 6035dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 6045dc62b1bSWANG Cong if (err < 0) { 6055dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 6065dc62b1bSWANG Cong -err); 6075dc62b1bSWANG Cong return 1; 6085dc62b1bSWANG Cong } 6095dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 6105dc62b1bSWANG Cong return 0; 6115dc62b1bSWANG Cong 6125dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 6135dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 6145dc62b1bSWANG Cong from_cmdline, from_cow, cow); 6155dc62b1bSWANG Cong return 1; 6165dc62b1bSWANG Cong } 6175dc62b1bSWANG Cong 6185dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 6195dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 6205dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6215dc62b1bSWANG Cong int *create_cow_out) 6225dc62b1bSWANG Cong { 6235dc62b1bSWANG Cong time_t mtime; 6245dc62b1bSWANG Cong unsigned long long size; 6255dc62b1bSWANG Cong __u32 version, align; 6265dc62b1bSWANG Cong char *backing_file; 6275dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6285dc62b1bSWANG Cong 6295dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6305dc62b1bSWANG Cong if (fd < 0) { 6315dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6325dc62b1bSWANG Cong *create_cow_out = 1; 6335dc62b1bSWANG Cong if (!openflags->w || 6345dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 6355dc62b1bSWANG Cong return fd; 6365dc62b1bSWANG Cong openflags->w = 0; 6375dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6385dc62b1bSWANG Cong if (fd < 0) 6395dc62b1bSWANG Cong return fd; 6405dc62b1bSWANG Cong } 6415dc62b1bSWANG Cong 6425dc62b1bSWANG Cong if (shared) 6435dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 6445dc62b1bSWANG Cong else { 6455dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 6465dc62b1bSWANG Cong if (err < 0) { 6475dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 6485dc62b1bSWANG Cong file, -err); 6495dc62b1bSWANG Cong goto out_close; 6505dc62b1bSWANG Cong } 6515dc62b1bSWANG Cong } 6525dc62b1bSWANG Cong 6535dc62b1bSWANG Cong /* Successful return case! */ 6545dc62b1bSWANG Cong if (backing_file_out == NULL) 6555dc62b1bSWANG Cong return fd; 6565dc62b1bSWANG Cong 6575dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 6585dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 6595dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 6605dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 6615dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 6625dc62b1bSWANG Cong goto out_close; 6635dc62b1bSWANG Cong } 6645dc62b1bSWANG Cong if (err) 6655dc62b1bSWANG Cong return fd; 6665dc62b1bSWANG Cong 6675dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 6685dc62b1bSWANG Cong file); 6695dc62b1bSWANG Cong 6705dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 6715dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 6725dc62b1bSWANG Cong mtime)) { 6735dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 6745dc62b1bSWANG Cong *backing_file_out); 6755dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 6765dc62b1bSWANG Cong sectorsize, align, &size); 6775dc62b1bSWANG Cong if (err) { 6785dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 6795dc62b1bSWANG Cong goto out_close; 6805dc62b1bSWANG Cong } 6815dc62b1bSWANG Cong } else { 6825dc62b1bSWANG Cong *backing_file_out = backing_file; 6835dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 6845dc62b1bSWANG Cong if (err) 6855dc62b1bSWANG Cong goto out_close; 6865dc62b1bSWANG Cong } 6875dc62b1bSWANG Cong 6885dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 6895dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 6905dc62b1bSWANG Cong 6915dc62b1bSWANG Cong return fd; 6925dc62b1bSWANG Cong out_close: 6935dc62b1bSWANG Cong os_close_file(fd); 6945dc62b1bSWANG Cong return err; 6955dc62b1bSWANG Cong } 6965dc62b1bSWANG Cong 6975dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 6985dc62b1bSWANG Cong struct openflags flags, 6995dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 7005dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 7015dc62b1bSWANG Cong { 7025dc62b1bSWANG Cong int err, fd; 7035dc62b1bSWANG Cong 7045dc62b1bSWANG Cong flags.c = 1; 7055dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 7065dc62b1bSWANG Cong if (fd < 0) { 7075dc62b1bSWANG Cong err = fd; 7085dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 7095dc62b1bSWANG Cong cow_file, -err); 7105dc62b1bSWANG Cong goto out; 7115dc62b1bSWANG Cong } 7125dc62b1bSWANG Cong 7135dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 7145dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 7155dc62b1bSWANG Cong data_offset_out); 7165dc62b1bSWANG Cong if (!err) 7175dc62b1bSWANG Cong return fd; 7185dc62b1bSWANG Cong os_close_file(fd); 7195dc62b1bSWANG Cong out: 7205dc62b1bSWANG Cong return err; 7215dc62b1bSWANG Cong } 7225dc62b1bSWANG Cong 7235f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7241da177e4SLinus Torvalds { 7257d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7267d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7271da177e4SLinus Torvalds return; 7281da177e4SLinus Torvalds 7297d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7307d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7317d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7321da177e4SLinus Torvalds } 7331da177e4SLinus Torvalds 7347d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 7351da177e4SLinus Torvalds { 7361da177e4SLinus Torvalds struct openflags flags; 7371da177e4SLinus Torvalds char **back_ptr; 7381da177e4SLinus Torvalds int err, create_cow, *create_ptr; 7390bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 7401da177e4SLinus Torvalds 7417d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 7421da177e4SLinus Torvalds create_cow = 0; 7437d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 7447d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 7450bf16bffSPaolo 'Blaisorblade' Giarrusso 7460bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 7477d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 7487d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 7496c29256cSJeff Dike create_ptr); 7501da177e4SLinus Torvalds 7510bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 7520bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 7537d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags, 1 << 9, PAGE_SIZE, 7547d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 7557d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 7567d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 7570bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 7581da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 7597d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 7601da177e4SLinus Torvalds } 7611da177e4SLinus Torvalds } 7621da177e4SLinus Torvalds 7630bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 7647d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 7650bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 7660bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 7671da177e4SLinus Torvalds } 7680bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 7691da177e4SLinus Torvalds 7707d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 771f4768ffdSJeff Dike blk_queue_max_sectors(ubd_dev->queue, 8 * sizeof(long)); 772f4768ffdSJeff Dike 7731da177e4SLinus Torvalds err = -ENOMEM; 774da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 7757d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 7761da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 7771da177e4SLinus Torvalds goto error; 7781da177e4SLinus Torvalds } 7791da177e4SLinus Torvalds flush_tlb_kernel_vm(); 7801da177e4SLinus Torvalds 7817d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 7827d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 7837d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 7841da177e4SLinus Torvalds if(err < 0) 7851da177e4SLinus Torvalds goto error; 7861da177e4SLinus Torvalds 7877d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 7881da177e4SLinus Torvalds flags.w = 0; 7897d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 7906c29256cSJeff Dike NULL, NULL, NULL, NULL); 7911da177e4SLinus Torvalds if(err < 0) goto error; 7927d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 7931da177e4SLinus Torvalds } 794dc764e50SJeff Dike return 0; 7951da177e4SLinus Torvalds error: 7967d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 797dc764e50SJeff Dike return err; 7981da177e4SLinus Torvalds } 7991da177e4SLinus Torvalds 8002e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 8012e3f5251SJeff Dike { 8022e3f5251SJeff Dike struct ubd *ubd_dev = dev->driver_data; 8032e3f5251SJeff Dike 8042e3f5251SJeff Dike blk_cleanup_queue(ubd_dev->queue); 8052e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 8062e3f5251SJeff Dike } 8072e3f5251SJeff Dike 8085f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 8091da177e4SLinus Torvalds struct gendisk **disk_out) 8101da177e4SLinus Torvalds { 8111da177e4SLinus Torvalds struct gendisk *disk; 8121da177e4SLinus Torvalds 8131da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 8141da177e4SLinus Torvalds if(disk == NULL) 815dc764e50SJeff Dike return -ENOMEM; 8161da177e4SLinus Torvalds 8171da177e4SLinus Torvalds disk->major = major; 8181da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 8191da177e4SLinus Torvalds disk->fops = &ubd_blops; 8201da177e4SLinus Torvalds set_capacity(disk, size / 512); 821792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) 8221da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 823ce7b0f46SGreg Kroah-Hartman else 8241da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 8251da177e4SLinus Torvalds 8261da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 827792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) { 8287d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 8297d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 8302e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 8312e3f5251SJeff Dike ubd_devs[unit].pdev.dev.driver_data = &ubd_devs[unit]; 8327d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 8337d314e34SPaolo 'Blaisorblade' Giarrusso disk->driverfs_dev = &ubd_devs[unit].pdev.dev; 8341da177e4SLinus Torvalds } 8351da177e4SLinus Torvalds 8367d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 83762f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 8381da177e4SLinus Torvalds add_disk(disk); 8391da177e4SLinus Torvalds 8401da177e4SLinus Torvalds *disk_out = disk; 8411da177e4SLinus Torvalds return 0; 8421da177e4SLinus Torvalds } 8431da177e4SLinus Torvalds 8441da177e4SLinus Torvalds #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) 8451da177e4SLinus Torvalds 846f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 8471da177e4SLinus Torvalds { 8487d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 849f28169d2SJeff Dike int err = 0; 8501da177e4SLinus Torvalds 8517d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 852ec7cf783SJeff Dike goto out; 8531da177e4SLinus Torvalds 8547d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 855f28169d2SJeff Dike if(err < 0){ 856f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 85780c13749SJeff Dike goto out; 858f28169d2SJeff Dike } 8591da177e4SLinus Torvalds 8607d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 8611da177e4SLinus Torvalds 862a0044bdfSJeff Dike INIT_LIST_HEAD(&ubd_dev->restart); 8634f40c055SWANG Cong sg_init_table(ubd_dev->sg, MAX_SG); 864a0044bdfSJeff Dike 86562f96cb0SJeff Dike err = -ENOMEM; 86662f96cb0SJeff Dike ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); 86762f96cb0SJeff Dike if (ubd_dev->queue == NULL) { 86862f96cb0SJeff Dike *error_out = "Failed to initialize device queue"; 86980c13749SJeff Dike goto out; 87062f96cb0SJeff Dike } 87162f96cb0SJeff Dike ubd_dev->queue->queuedata = ubd_dev; 87262f96cb0SJeff Dike 873a0044bdfSJeff Dike blk_queue_max_hw_segments(ubd_dev->queue, MAX_SG); 874792dd4fcSChristoph Hellwig err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); 87562f96cb0SJeff Dike if(err){ 87662f96cb0SJeff Dike *error_out = "Failed to register device"; 87762f96cb0SJeff Dike goto out_cleanup; 87862f96cb0SJeff Dike } 8791da177e4SLinus Torvalds 880792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) 8815f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 8821da177e4SLinus Torvalds &fake_gendisk[n]); 8831da177e4SLinus Torvalds 88483380cc1SJeff Dike /* 88583380cc1SJeff Dike * Perhaps this should also be under the "if (fake_major)" above 88683380cc1SJeff Dike * using the fake_disk->disk_name 88783380cc1SJeff Dike */ 8881da177e4SLinus Torvalds if (fake_ide) 8891da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 8901da177e4SLinus Torvalds 891ec7cf783SJeff Dike err = 0; 892ec7cf783SJeff Dike out: 893ec7cf783SJeff Dike return err; 89462f96cb0SJeff Dike 89562f96cb0SJeff Dike out_cleanup: 89662f96cb0SJeff Dike blk_cleanup_queue(ubd_dev->queue); 89762f96cb0SJeff Dike goto out; 8981da177e4SLinus Torvalds } 8991da177e4SLinus Torvalds 900f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 9011da177e4SLinus Torvalds { 902e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 9031da177e4SLinus Torvalds 904f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 905f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 906f28169d2SJeff Dike * were set. 907f28169d2SJeff Dike */ 908970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 9091da177e4SLinus Torvalds if (str == NULL) { 910f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 911f28169d2SJeff Dike return -ENOMEM; 9121da177e4SLinus Torvalds } 913f28169d2SJeff Dike 914f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 915f28169d2SJeff Dike if (ret) 916e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 917f28169d2SJeff Dike 918e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 919e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 920d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 921e7f6552fSPaolo 'Blaisorblade' Giarrusso } 9221da177e4SLinus Torvalds 923d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 924f28169d2SJeff Dike ret = ubd_add(n, error_out); 925e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 9267d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 927d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 9281da177e4SLinus Torvalds 929e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 930e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 931e7f6552fSPaolo 'Blaisorblade' Giarrusso 932e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 933e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 934e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 9351da177e4SLinus Torvalds } 9361da177e4SLinus Torvalds 9371da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 9381da177e4SLinus Torvalds { 9397d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 9401da177e4SLinus Torvalds int n, len = 0; 9411da177e4SLinus Torvalds 9421da177e4SLinus Torvalds n = parse_unit(&name); 9431da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 9441da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 945dc764e50SJeff Dike return -1; 9461da177e4SLinus Torvalds } 9471da177e4SLinus Torvalds 9487d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 949d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 9501da177e4SLinus Torvalds 9517d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 9521da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 9531da177e4SLinus Torvalds goto out; 9541da177e4SLinus Torvalds } 9551da177e4SLinus Torvalds 9567d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 9571da177e4SLinus Torvalds 9587d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 9591da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 9607d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 9611da177e4SLinus Torvalds } 9621da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 9631da177e4SLinus Torvalds 9641da177e4SLinus Torvalds out: 965d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 966dc764e50SJeff Dike return len; 9671da177e4SLinus Torvalds } 9681da177e4SLinus Torvalds 96929d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 97029d56cfeSJeff Dike { 97129d56cfeSJeff Dike int n; 97229d56cfeSJeff Dike 97329d56cfeSJeff Dike n = parse_unit(str); 97429d56cfeSJeff Dike *start_out = 0; 97529d56cfeSJeff Dike *end_out = MAX_DEV - 1; 97629d56cfeSJeff Dike return n; 97729d56cfeSJeff Dike } 97829d56cfeSJeff Dike 979f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 9801da177e4SLinus Torvalds { 9812e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 9827d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 98329d56cfeSJeff Dike int err = -ENODEV; 9841da177e4SLinus Torvalds 985d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 9861da177e4SLinus Torvalds 9877d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 98829d56cfeSJeff Dike 9897d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 99029d56cfeSJeff Dike goto out; 99129d56cfeSJeff Dike 99229d56cfeSJeff Dike /* you cannot remove a open disk */ 99329d56cfeSJeff Dike err = -EBUSY; 9947d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 99529d56cfeSJeff Dike goto out; 99629d56cfeSJeff Dike 9971da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 998b47d2debSJeff Dike if(disk != NULL){ 999b47d2debSJeff Dike del_gendisk(disk); 1000b47d2debSJeff Dike put_disk(disk); 1001b47d2debSJeff Dike } 10021da177e4SLinus Torvalds 10031da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 10041da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 10051da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 10061da177e4SLinus Torvalds fake_gendisk[n] = NULL; 10071da177e4SLinus Torvalds } 10081da177e4SLinus Torvalds 10091da177e4SLinus Torvalds err = 0; 10102e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 10111da177e4SLinus Torvalds out: 1012d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 101329d56cfeSJeff Dike return err; 10141da177e4SLinus Torvalds } 10151da177e4SLinus Torvalds 1016f28169d2SJeff Dike /* All these are called by mconsole in process context and without 1017b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 1018f28169d2SJeff Dike */ 10191da177e4SLinus Torvalds static struct mc_device ubd_mc = { 102084f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 10211da177e4SLinus Torvalds .name = "ubd", 10221da177e4SLinus Torvalds .config = ubd_config, 10231da177e4SLinus Torvalds .get_config = ubd_get_config, 102429d56cfeSJeff Dike .id = ubd_id, 10251da177e4SLinus Torvalds .remove = ubd_remove, 10261da177e4SLinus Torvalds }; 10271da177e4SLinus Torvalds 1028d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 10291da177e4SLinus Torvalds { 10301da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 10311da177e4SLinus Torvalds return 0; 10321da177e4SLinus Torvalds } 10331da177e4SLinus Torvalds 10341da177e4SLinus Torvalds __initcall(ubd_mc_init); 10351da177e4SLinus Torvalds 1036d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1037d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1038d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1039d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1040b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1041d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1042d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1043b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1044b8831a1dSJeff Dike 1045dc764e50SJeff Dike return 0; 1046d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1047d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1048d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1049d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1050b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 10513ae5eaecSRussell King static struct platform_driver ubd_driver = { 10523ae5eaecSRussell King .driver = { 10531da177e4SLinus Torvalds .name = DRIVER_NAME, 10543ae5eaecSRussell King }, 10551da177e4SLinus Torvalds }; 10561da177e4SLinus Torvalds 1057d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 10581da177e4SLinus Torvalds { 1059f28169d2SJeff Dike char *error; 1060f28169d2SJeff Dike int i, err; 10611da177e4SLinus Torvalds 1062792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 10631da177e4SLinus Torvalds return -1; 10641da177e4SLinus Torvalds 1065792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 10661da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 10671da177e4SLinus Torvalds 10681da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 10691da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 10701da177e4SLinus Torvalds return -1; 10711da177e4SLinus Torvalds } 10723ae5eaecSRussell King platform_driver_register(&ubd_driver); 1073b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1074f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1075f28169d2SJeff Dike err = ubd_add(i, &error); 1076f28169d2SJeff Dike if(err) 1077f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1078f28169d2SJeff Dike "%s\n", i, error); 1079f28169d2SJeff Dike } 1080b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 10811da177e4SLinus Torvalds return 0; 10821da177e4SLinus Torvalds } 10831da177e4SLinus Torvalds 10841da177e4SLinus Torvalds late_initcall(ubd_init); 10851da177e4SLinus Torvalds 1086d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 108791acb21fSJeff Dike unsigned long stack; 108891acb21fSJeff Dike int err; 108991acb21fSJeff Dike 109091acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 109191acb21fSJeff Dike if(global_openflags.s){ 109291acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 109391acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 109491acb21fSJeff Dike * enough. So use anyway the io thread. */ 109591acb21fSJeff Dike } 109691acb21fSJeff Dike stack = alloc_stack(0, 0); 109791acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 109891acb21fSJeff Dike &thread_fd); 109991acb21fSJeff Dike if(io_pid < 0){ 110091acb21fSJeff Dike printk(KERN_ERR 110191acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 110291acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 110391acb21fSJeff Dike io_pid = -1; 1104dc764e50SJeff Dike return 0; 110591acb21fSJeff Dike } 110691acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 11077d314e34SPaolo 'Blaisorblade' Giarrusso IRQF_DISABLED, "ubd", ubd_devs); 110891acb21fSJeff Dike if(err != 0) 110991acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1110f4c57a78SJeff Dike return 0; 111191acb21fSJeff Dike } 111291acb21fSJeff Dike 111391acb21fSJeff Dike device_initcall(ubd_driver_init); 111491acb21fSJeff Dike 1115a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 11161da177e4SLinus Torvalds { 1117a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 11187d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 11191da177e4SLinus Torvalds int err = 0; 11201da177e4SLinus Torvalds 11217d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 11227d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 11231da177e4SLinus Torvalds if(err){ 11241da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 11257d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 11261da177e4SLinus Torvalds goto out; 11271da177e4SLinus Torvalds } 11281da177e4SLinus Torvalds } 11297d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 11307d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 11312c49be99SPaolo 'Blaisorblade' Giarrusso 11322c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 11332c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1134a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 11355f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 11361da177e4SLinus Torvalds err = -EROFS; 11372c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 11381da177e4SLinus Torvalds out: 1139dc764e50SJeff Dike return err; 11401da177e4SLinus Torvalds } 11411da177e4SLinus Torvalds 1142a625c998SAl Viro static int ubd_release(struct gendisk *disk, fmode_t mode) 11431da177e4SLinus Torvalds { 11447d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 11451da177e4SLinus Torvalds 11467d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 11475f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 1148dc764e50SJeff Dike return 0; 11491da177e4SLinus Torvalds } 11501da177e4SLinus Torvalds 115191acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 115291acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 115391acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 115491acb21fSJeff Dike __u64 bitmap_len) 11551da177e4SLinus Torvalds { 115691acb21fSJeff Dike __u64 sector = io_offset >> 9; 115791acb21fSJeff Dike int i, update_bitmap = 0; 11581da177e4SLinus Torvalds 115991acb21fSJeff Dike for(i = 0; i < length >> 9; i++){ 116091acb21fSJeff Dike if(cow_mask != NULL) 116191acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 116291acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 116309ace81cSJeff Dike continue; 11641da177e4SLinus Torvalds 116591acb21fSJeff Dike update_bitmap = 1; 116691acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 11671da177e4SLinus Torvalds } 116891acb21fSJeff Dike 116991acb21fSJeff Dike if(!update_bitmap) 117091acb21fSJeff Dike return; 117191acb21fSJeff Dike 117291acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 117391acb21fSJeff Dike 117491acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 117591acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 117691acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 117791acb21fSJeff Dike * for the original diagnosis. 117891acb21fSJeff Dike */ 11796d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 11806d074242SJiri Olsa sizeof(unsigned long)) - 1)) 118191acb21fSJeff Dike (*cow_offset)--; 118291acb21fSJeff Dike 118391acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 118491acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 118591acb21fSJeff Dike 118691acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 118791acb21fSJeff Dike *cow_offset += bitmap_offset; 118891acb21fSJeff Dike } 118991acb21fSJeff Dike 119091acb21fSJeff Dike static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, 119191acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 119291acb21fSJeff Dike { 119391acb21fSJeff Dike __u64 sector = req->offset >> 9; 119491acb21fSJeff Dike int i; 119591acb21fSJeff Dike 119691acb21fSJeff Dike if(req->length > (sizeof(req->sector_mask) * 8) << 9) 119791acb21fSJeff Dike panic("Operation too long"); 119891acb21fSJeff Dike 119991acb21fSJeff Dike if(req->op == UBD_READ) { 120091acb21fSJeff Dike for(i = 0; i < req->length >> 9; i++){ 120191acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 120291acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 120391acb21fSJeff Dike &req->sector_mask); 120491acb21fSJeff Dike } 120591acb21fSJeff Dike } 120691acb21fSJeff Dike else cowify_bitmap(req->offset, req->length, &req->sector_mask, 120791acb21fSJeff Dike &req->cow_offset, bitmap, bitmap_offset, 120891acb21fSJeff Dike req->bitmap_words, bitmap_len); 12091da177e4SLinus Torvalds } 12101da177e4SLinus Torvalds 121162f96cb0SJeff Dike /* Called with dev->lock held */ 1212a0044bdfSJeff Dike static void prepare_request(struct request *req, struct io_thread_req *io_req, 1213a0044bdfSJeff Dike unsigned long long offset, int page_offset, 1214a0044bdfSJeff Dike int len, struct page *page) 12151da177e4SLinus Torvalds { 12161da177e4SLinus Torvalds struct gendisk *disk = req->rq_disk; 12177d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 121891acb21fSJeff Dike 121962f96cb0SJeff Dike io_req->req = req; 1220a0044bdfSJeff Dike io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : 1221a0044bdfSJeff Dike ubd_dev->fd; 12227d314e34SPaolo 'Blaisorblade' Giarrusso io_req->fds[1] = ubd_dev->fd; 122391acb21fSJeff Dike io_req->cow_offset = -1; 12241da177e4SLinus Torvalds io_req->offset = offset; 12251da177e4SLinus Torvalds io_req->length = len; 12261da177e4SLinus Torvalds io_req->error = 0; 122791acb21fSJeff Dike io_req->sector_mask = 0; 122891acb21fSJeff Dike 122991acb21fSJeff Dike io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; 12301da177e4SLinus Torvalds io_req->offsets[0] = 0; 12317d314e34SPaolo 'Blaisorblade' Giarrusso io_req->offsets[1] = ubd_dev->cow.data_offset; 1232a0044bdfSJeff Dike io_req->buffer = page_address(page) + page_offset; 12331da177e4SLinus Torvalds io_req->sectorsize = 1 << 9; 12341da177e4SLinus Torvalds 12357d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL) 1236a0044bdfSJeff Dike cowify_req(io_req, ubd_dev->cow.bitmap, 1237a0044bdfSJeff Dike ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); 123891acb21fSJeff Dike 12391da177e4SLinus Torvalds } 12401da177e4SLinus Torvalds 124162f96cb0SJeff Dike /* Called with dev->lock held */ 1242165125e1SJens Axboe static void do_ubd_request(struct request_queue *q) 12431da177e4SLinus Torvalds { 12442adcec21SJeff Dike struct io_thread_req *io_req; 12451da177e4SLinus Torvalds struct request *req; 12460a6d3a2aSJeff Dike int n, last_sectors; 12471da177e4SLinus Torvalds 1248a0044bdfSJeff Dike while(1){ 12492a9529a0SJeff Dike struct ubd *dev = q->queuedata; 1250a0044bdfSJeff Dike if(dev->end_sg == 0){ 1251a0044bdfSJeff Dike struct request *req = elv_next_request(q); 1252a0044bdfSJeff Dike if(req == NULL) 125391acb21fSJeff Dike return; 1254a0044bdfSJeff Dike 1255a0044bdfSJeff Dike dev->request = req; 1256a0044bdfSJeff Dike blkdev_dequeue_request(req); 1257a0044bdfSJeff Dike dev->start_sg = 0; 1258a0044bdfSJeff Dike dev->end_sg = blk_rq_map_sg(q, req, dev->sg); 1259a0044bdfSJeff Dike } 1260a0044bdfSJeff Dike 1261a0044bdfSJeff Dike req = dev->request; 12620a6d3a2aSJeff Dike last_sectors = 0; 1263a0044bdfSJeff Dike while(dev->start_sg < dev->end_sg){ 1264a0044bdfSJeff Dike struct scatterlist *sg = &dev->sg[dev->start_sg]; 1265a0044bdfSJeff Dike 12660a6d3a2aSJeff Dike req->sector += last_sectors; 12672adcec21SJeff Dike io_req = kmalloc(sizeof(struct io_thread_req), 1268990c5587SPeter Zijlstra GFP_ATOMIC); 12692adcec21SJeff Dike if(io_req == NULL){ 12702adcec21SJeff Dike if(list_empty(&dev->restart)) 12712adcec21SJeff Dike list_add(&dev->restart, &restart); 12722adcec21SJeff Dike return; 12732adcec21SJeff Dike } 12742adcec21SJeff Dike prepare_request(req, io_req, 1275a0044bdfSJeff Dike (unsigned long long) req->sector << 9, 127645711f1aSJens Axboe sg->offset, sg->length, sg_page(sg)); 1277a0044bdfSJeff Dike 12780a6d3a2aSJeff Dike last_sectors = sg->length >> 9; 1279a6ea4cceSJeff Dike n = os_write_file(thread_fd, &io_req, 12802adcec21SJeff Dike sizeof(struct io_thread_req *)); 12812adcec21SJeff Dike if(n != sizeof(struct io_thread_req *)){ 1282a0044bdfSJeff Dike if(n != -EAGAIN) 128391acb21fSJeff Dike printk("write to io thread failed, " 128491acb21fSJeff Dike "errno = %d\n", -n); 1285a0044bdfSJeff Dike else if(list_empty(&dev->restart)) 1286a0044bdfSJeff Dike list_add(&dev->restart, &restart); 128712429bf9SMiklos Szeredi kfree(io_req); 1288a0044bdfSJeff Dike return; 128991acb21fSJeff Dike } 1290a0044bdfSJeff Dike 1291a0044bdfSJeff Dike dev->start_sg++; 1292a0044bdfSJeff Dike } 1293a0044bdfSJeff Dike dev->end_sg = 0; 1294a0044bdfSJeff Dike dev->request = NULL; 129591acb21fSJeff Dike } 12961da177e4SLinus Torvalds } 12971da177e4SLinus Torvalds 1298a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1299a885c8c4SChristoph Hellwig { 13007d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1301a885c8c4SChristoph Hellwig 1302a885c8c4SChristoph Hellwig geo->heads = 128; 1303a885c8c4SChristoph Hellwig geo->sectors = 32; 13047d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1305a885c8c4SChristoph Hellwig return 0; 1306a885c8c4SChristoph Hellwig } 1307a885c8c4SChristoph Hellwig 1308a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 13091da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 13101da177e4SLinus Torvalds { 1311a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 131273855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 13131da177e4SLinus Torvalds 13141da177e4SLinus Torvalds switch (cmd) { 13151da177e4SLinus Torvalds struct cdrom_volctrl volume; 13161da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 131773855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 131873855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 131973855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 132073855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 13211da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 13221da177e4SLinus Torvalds sizeof(ubd_id))) 1323dc764e50SJeff Dike return -EFAULT; 1324dc764e50SJeff Dike return 0; 13251da177e4SLinus Torvalds 13261da177e4SLinus Torvalds case CDROMVOLREAD: 13271da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1328dc764e50SJeff Dike return -EFAULT; 13291da177e4SLinus Torvalds volume.channel0 = 255; 13301da177e4SLinus Torvalds volume.channel1 = 255; 13311da177e4SLinus Torvalds volume.channel2 = 255; 13321da177e4SLinus Torvalds volume.channel3 = 255; 13331da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1334dc764e50SJeff Dike return -EFAULT; 1335dc764e50SJeff Dike return 0; 13361da177e4SLinus Torvalds } 1337dc764e50SJeff Dike return -EINVAL; 13381da177e4SLinus Torvalds } 13391da177e4SLinus Torvalds 134091acb21fSJeff Dike static int update_bitmap(struct io_thread_req *req) 13411da177e4SLinus Torvalds { 134291acb21fSJeff Dike int n; 134391acb21fSJeff Dike 134491acb21fSJeff Dike if(req->cow_offset == -1) 1345dc764e50SJeff Dike return 0; 134691acb21fSJeff Dike 134791acb21fSJeff Dike n = os_seek_file(req->fds[1], req->cow_offset); 134891acb21fSJeff Dike if(n < 0){ 134991acb21fSJeff Dike printk("do_io - bitmap lseek failed : err = %d\n", -n); 1350dc764e50SJeff Dike return 1; 135191acb21fSJeff Dike } 135291acb21fSJeff Dike 1353a6ea4cceSJeff Dike n = os_write_file(req->fds[1], &req->bitmap_words, 135491acb21fSJeff Dike sizeof(req->bitmap_words)); 135591acb21fSJeff Dike if(n != sizeof(req->bitmap_words)){ 135691acb21fSJeff Dike printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, 135791acb21fSJeff Dike req->fds[1]); 1358dc764e50SJeff Dike return 1; 135991acb21fSJeff Dike } 136091acb21fSJeff Dike 1361dc764e50SJeff Dike return 0; 136291acb21fSJeff Dike } 136391acb21fSJeff Dike 13645dc62b1bSWANG Cong static void do_io(struct io_thread_req *req) 136591acb21fSJeff Dike { 13661da177e4SLinus Torvalds char *buf; 136791acb21fSJeff Dike unsigned long len; 136891acb21fSJeff Dike int n, nsectors, start, end, bit; 136991acb21fSJeff Dike int err; 13701da177e4SLinus Torvalds __u64 off; 13711da177e4SLinus Torvalds 13721da177e4SLinus Torvalds nsectors = req->length / req->sectorsize; 13731da177e4SLinus Torvalds start = 0; 13741da177e4SLinus Torvalds do { 137591acb21fSJeff Dike bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); 13761da177e4SLinus Torvalds end = start; 13771da177e4SLinus Torvalds while((end < nsectors) && 137891acb21fSJeff Dike (ubd_test_bit(end, (unsigned char *) 137991acb21fSJeff Dike &req->sector_mask) == bit)) 13801da177e4SLinus Torvalds end++; 13811da177e4SLinus Torvalds 138291acb21fSJeff Dike off = req->offset + req->offsets[bit] + 13831da177e4SLinus Torvalds start * req->sectorsize; 13841da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 13851da177e4SLinus Torvalds buf = &req->buffer[start * req->sectorsize]; 13861da177e4SLinus Torvalds 138791acb21fSJeff Dike err = os_seek_file(req->fds[bit], off); 138891acb21fSJeff Dike if(err < 0){ 138991acb21fSJeff Dike printk("do_io - lseek failed : err = %d\n", -err); 13901da177e4SLinus Torvalds req->error = 1; 13911da177e4SLinus Torvalds return; 13921da177e4SLinus Torvalds } 139391acb21fSJeff Dike if(req->op == UBD_READ){ 139491acb21fSJeff Dike n = 0; 139591acb21fSJeff Dike do { 139691acb21fSJeff Dike buf = &buf[n]; 139791acb21fSJeff Dike len -= n; 1398a6ea4cceSJeff Dike n = os_read_file(req->fds[bit], buf, len); 139991acb21fSJeff Dike if (n < 0) { 140091acb21fSJeff Dike printk("do_io - read failed, err = %d " 140191acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 14021da177e4SLinus Torvalds req->error = 1; 14031da177e4SLinus Torvalds return; 14041da177e4SLinus Torvalds } 140591acb21fSJeff Dike } while((n < len) && (n != 0)); 140691acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 140791acb21fSJeff Dike } else { 1408a6ea4cceSJeff Dike n = os_write_file(req->fds[bit], buf, len); 140991acb21fSJeff Dike if(n != len){ 141091acb21fSJeff Dike printk("do_io - write failed err = %d " 141191acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 141291acb21fSJeff Dike req->error = 1; 141391acb21fSJeff Dike return; 141491acb21fSJeff Dike } 141591acb21fSJeff Dike } 14161da177e4SLinus Torvalds 14171da177e4SLinus Torvalds start = end; 14181da177e4SLinus Torvalds } while(start < nsectors); 141991acb21fSJeff Dike 142091acb21fSJeff Dike req->error = update_bitmap(req); 14211da177e4SLinus Torvalds } 142291acb21fSJeff Dike 142391acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 142491acb21fSJeff Dike * from ubd_init, which is an initcall. 142591acb21fSJeff Dike */ 142691acb21fSJeff Dike int kernel_fd = -1; 142791acb21fSJeff Dike 1428d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1429d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 143091acb21fSJeff Dike 143191acb21fSJeff Dike int io_thread(void *arg) 143291acb21fSJeff Dike { 14332adcec21SJeff Dike struct io_thread_req *req; 143491acb21fSJeff Dike int n; 143591acb21fSJeff Dike 143691acb21fSJeff Dike ignore_sigwinch_sig(); 143791acb21fSJeff Dike while(1){ 1438a6ea4cceSJeff Dike n = os_read_file(kernel_fd, &req, 14392adcec21SJeff Dike sizeof(struct io_thread_req *)); 14402adcec21SJeff Dike if(n != sizeof(struct io_thread_req *)){ 144191acb21fSJeff Dike if(n < 0) 144291acb21fSJeff Dike printk("io_thread - read failed, fd = %d, " 144391acb21fSJeff Dike "err = %d\n", kernel_fd, -n); 144491acb21fSJeff Dike else { 144591acb21fSJeff Dike printk("io_thread - short read, fd = %d, " 144691acb21fSJeff Dike "length = %d\n", kernel_fd, n); 144791acb21fSJeff Dike } 144891acb21fSJeff Dike continue; 144991acb21fSJeff Dike } 145091acb21fSJeff Dike io_count++; 14512adcec21SJeff Dike do_io(req); 1452a6ea4cceSJeff Dike n = os_write_file(kernel_fd, &req, 14532adcec21SJeff Dike sizeof(struct io_thread_req *)); 14542adcec21SJeff Dike if(n != sizeof(struct io_thread_req *)) 145591acb21fSJeff Dike printk("io_thread - write failed, fd = %d, err = %d\n", 145691acb21fSJeff Dike kernel_fd, -n); 145791acb21fSJeff Dike } 145891acb21fSJeff Dike 14591b57e9c2SJeff Dike return 0; 14601b57e9c2SJeff Dike } 1461