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" 341da177e4SLinus Torvalds #include "linux/vmalloc.h" 351da177e4SLinus Torvalds #include "linux/blkpg.h" 361da177e4SLinus Torvalds #include "linux/genhd.h" 371da177e4SLinus Torvalds #include "linux/spinlock.h" 38d052d1beSRussell King #include "linux/platform_device.h" 3923464ffaSWANG Cong #include "linux/scatterlist.h" 401da177e4SLinus Torvalds #include "asm/segment.h" 411da177e4SLinus Torvalds #include "asm/uaccess.h" 421da177e4SLinus Torvalds #include "asm/irq.h" 431da177e4SLinus Torvalds #include "asm/types.h" 441da177e4SLinus Torvalds #include "asm/tlbflush.h" 451da177e4SLinus Torvalds #include "mem_user.h" 461da177e4SLinus Torvalds #include "kern_util.h" 471da177e4SLinus Torvalds #include "kern.h" 481da177e4SLinus Torvalds #include "mconsole_kern.h" 491da177e4SLinus Torvalds #include "init.h" 501da177e4SLinus Torvalds #include "irq_user.h" 511da177e4SLinus Torvalds #include "irq_kern.h" 521da177e4SLinus Torvalds #include "ubd_user.h" 531da177e4SLinus Torvalds #include "os.h" 541da177e4SLinus Torvalds #include "mem.h" 551da177e4SLinus Torvalds #include "mem_kern.h" 561da177e4SLinus Torvalds #include "cow.h" 571da177e4SLinus Torvalds 587b9014c1SJeff Dike enum ubd_req { UBD_READ, UBD_WRITE }; 591da177e4SLinus Torvalds 601da177e4SLinus Torvalds struct io_thread_req { 6162f96cb0SJeff Dike struct request *req; 6291acb21fSJeff Dike enum ubd_req op; 631da177e4SLinus Torvalds int fds[2]; 641da177e4SLinus Torvalds unsigned long offsets[2]; 651da177e4SLinus Torvalds unsigned long long offset; 661da177e4SLinus Torvalds unsigned long length; 671da177e4SLinus Torvalds char *buffer; 681da177e4SLinus Torvalds int sectorsize; 6991acb21fSJeff Dike unsigned long sector_mask; 7091acb21fSJeff Dike unsigned long long cow_offset; 7191acb21fSJeff Dike unsigned long bitmap_words[2]; 721da177e4SLinus Torvalds int error; 731da177e4SLinus Torvalds }; 741da177e4SLinus Torvalds 7591acb21fSJeff Dike static inline int ubd_test_bit(__u64 bit, unsigned char *data) 761da177e4SLinus Torvalds { 771da177e4SLinus Torvalds __u64 n; 781da177e4SLinus Torvalds int bits, off; 791da177e4SLinus Torvalds 8091acb21fSJeff Dike bits = sizeof(data[0]) * 8; 811da177e4SLinus Torvalds n = bit / bits; 821da177e4SLinus Torvalds off = bit % bits; 83dc764e50SJeff Dike return (data[n] & (1 << off)) != 0; 841da177e4SLinus Torvalds } 851da177e4SLinus Torvalds 8691acb21fSJeff Dike static inline void ubd_set_bit(__u64 bit, unsigned char *data) 871da177e4SLinus Torvalds { 881da177e4SLinus Torvalds __u64 n; 891da177e4SLinus Torvalds int bits, off; 901da177e4SLinus Torvalds 9191acb21fSJeff Dike bits = sizeof(data[0]) * 8; 921da177e4SLinus Torvalds n = bit / bits; 931da177e4SLinus Torvalds off = bit % bits; 9491acb21fSJeff Dike data[n] |= (1 << off); 951da177e4SLinus Torvalds } 961da177e4SLinus Torvalds /*End stuff from ubd_user.h*/ 971da177e4SLinus Torvalds 981da177e4SLinus Torvalds #define DRIVER_NAME "uml-blkdev" 991da177e4SLinus Torvalds 100d7fb2c38SPaolo 'Blaisorblade' Giarrusso static DEFINE_MUTEX(ubd_lock); 1011da177e4SLinus Torvalds 102a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode); 103a625c998SAl Viro static int ubd_release(struct gendisk *disk, fmode_t mode); 104a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 1051da177e4SLinus Torvalds unsigned int cmd, unsigned long arg); 106a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); 1071da177e4SLinus Torvalds 10897d88ac8SPaolo 'Blaisorblade' Giarrusso #define MAX_DEV (16) 1091da177e4SLinus Torvalds 11083d5cde4SAlexey Dobriyan static const struct block_device_operations ubd_blops = { 1111da177e4SLinus Torvalds .owner = THIS_MODULE, 112a625c998SAl Viro .open = ubd_open, 113a625c998SAl Viro .release = ubd_release, 114a625c998SAl Viro .ioctl = ubd_ioctl, 115a885c8c4SChristoph Hellwig .getgeo = ubd_getgeo, 1161da177e4SLinus Torvalds }; 1171da177e4SLinus Torvalds 1181da177e4SLinus Torvalds /* Protected by ubd_lock */ 119792dd4fcSChristoph Hellwig static int fake_major = UBD_MAJOR; 1201da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1211da177e4SLinus Torvalds static struct gendisk *fake_gendisk[MAX_DEV]; 1221da177e4SLinus Torvalds 1231da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1241da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1251da177e4SLinus Torvalds .cl = 1 }) 1261da177e4SLinus Torvalds #else 1271da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1281da177e4SLinus Torvalds .cl = 1 }) 1291da177e4SLinus Torvalds #endif 1301da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1311da177e4SLinus Torvalds 1321da177e4SLinus Torvalds struct cow { 1332a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file name */ 1341da177e4SLinus Torvalds char *file; 1352a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file fd */ 1361da177e4SLinus Torvalds int fd; 1371da177e4SLinus Torvalds unsigned long *bitmap; 1381da177e4SLinus Torvalds unsigned long bitmap_len; 1391da177e4SLinus Torvalds int bitmap_offset; 1401da177e4SLinus Torvalds int data_offset; 1411da177e4SLinus Torvalds }; 1421da177e4SLinus Torvalds 143a0044bdfSJeff Dike #define MAX_SG 64 144a0044bdfSJeff Dike 1451da177e4SLinus Torvalds struct ubd { 146a0044bdfSJeff Dike struct list_head restart; 1472a9d32f6SPaolo 'Blaisorblade' Giarrusso /* name (and fd, below) of the file opened for writing, either the 1482a9d32f6SPaolo 'Blaisorblade' Giarrusso * backing or the cow file. */ 1491da177e4SLinus Torvalds char *file; 1501da177e4SLinus Torvalds int count; 1511da177e4SLinus Torvalds int fd; 1521da177e4SLinus Torvalds __u64 size; 1531da177e4SLinus Torvalds struct openflags boot_openflags; 1541da177e4SLinus Torvalds struct openflags openflags; 15584e945e3SPaolo 'Blaisorblade' Giarrusso unsigned shared:1; 15684e945e3SPaolo 'Blaisorblade' Giarrusso unsigned no_cow:1; 1571da177e4SLinus Torvalds struct cow cow; 1581da177e4SLinus Torvalds struct platform_device pdev; 15962f96cb0SJeff Dike struct request_queue *queue; 16062f96cb0SJeff Dike spinlock_t lock; 161a0044bdfSJeff Dike struct scatterlist sg[MAX_SG]; 162a0044bdfSJeff Dike struct request *request; 163a0044bdfSJeff Dike int start_sg, end_sg; 1641da177e4SLinus Torvalds }; 1651da177e4SLinus Torvalds 1661da177e4SLinus Torvalds #define DEFAULT_COW { \ 1671da177e4SLinus Torvalds .file = NULL, \ 1681da177e4SLinus Torvalds .fd = -1, \ 1691da177e4SLinus Torvalds .bitmap = NULL, \ 1701da177e4SLinus Torvalds .bitmap_offset = 0, \ 1711da177e4SLinus Torvalds .data_offset = 0, \ 1721da177e4SLinus Torvalds } 1731da177e4SLinus Torvalds 1741da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1751da177e4SLinus Torvalds .file = NULL, \ 1761da177e4SLinus Torvalds .count = 0, \ 1771da177e4SLinus Torvalds .fd = -1, \ 1781da177e4SLinus Torvalds .size = -1, \ 1791da177e4SLinus Torvalds .boot_openflags = OPEN_FLAGS, \ 1801da177e4SLinus Torvalds .openflags = OPEN_FLAGS, \ 1811da177e4SLinus Torvalds .no_cow = 0, \ 1826c29256cSJeff Dike .shared = 0, \ 1831da177e4SLinus Torvalds .cow = DEFAULT_COW, \ 18462f96cb0SJeff Dike .lock = SPIN_LOCK_UNLOCKED, \ 185a0044bdfSJeff Dike .request = NULL, \ 186a0044bdfSJeff Dike .start_sg = 0, \ 187a0044bdfSJeff Dike .end_sg = 0, \ 1881da177e4SLinus Torvalds } 1891da177e4SLinus Torvalds 190b8831a1dSJeff Dike /* Protected by ubd_lock */ 1915dc62b1bSWANG Cong static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; 1921da177e4SLinus Torvalds 1931da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 1941da177e4SLinus Torvalds static int fake_ide = 0; 1951da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 1961da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 1971da177e4SLinus Torvalds 1981da177e4SLinus Torvalds static void make_proc_ide(void) 1991da177e4SLinus Torvalds { 2001da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 2011da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 2021da177e4SLinus Torvalds } 2031da177e4SLinus Torvalds 2046613c5e8SAlexey Dobriyan static int fake_ide_media_proc_show(struct seq_file *m, void *v) 2051da177e4SLinus Torvalds { 2066613c5e8SAlexey Dobriyan seq_puts(m, "disk\n"); 2076613c5e8SAlexey Dobriyan return 0; 2086613c5e8SAlexey Dobriyan } 2091da177e4SLinus Torvalds 2106613c5e8SAlexey Dobriyan static int fake_ide_media_proc_open(struct inode *inode, struct file *file) 2116613c5e8SAlexey Dobriyan { 2126613c5e8SAlexey Dobriyan return single_open(file, fake_ide_media_proc_show, NULL); 2131da177e4SLinus Torvalds } 2146613c5e8SAlexey Dobriyan 2156613c5e8SAlexey Dobriyan static const struct file_operations fake_ide_media_proc_fops = { 2166613c5e8SAlexey Dobriyan .owner = THIS_MODULE, 2176613c5e8SAlexey Dobriyan .open = fake_ide_media_proc_open, 2186613c5e8SAlexey Dobriyan .read = seq_read, 2196613c5e8SAlexey Dobriyan .llseek = seq_lseek, 2206613c5e8SAlexey Dobriyan .release = single_release, 2216613c5e8SAlexey Dobriyan }; 2221da177e4SLinus Torvalds 223c0a9290eSWANG Cong static void make_ide_entries(const char *dev_name) 2241da177e4SLinus Torvalds { 2251da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2261da177e4SLinus Torvalds char name[64]; 2271da177e4SLinus Torvalds 2281da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2291da177e4SLinus Torvalds 2301da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2311da177e4SLinus Torvalds if(!dir) return; 2321da177e4SLinus Torvalds 2336613c5e8SAlexey Dobriyan ent = proc_create("media", S_IRUGO, dir, &fake_ide_media_proc_fops); 2341da177e4SLinus Torvalds if(!ent) return; 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; 454a0044bdfSJeff Dike static LIST_HEAD(restart); 45509ace81cSJeff Dike 4562fe30a34SPaolo 'Blaisorblade' Giarrusso /* XXX - move this inside ubd_intr. */ 45762f96cb0SJeff Dike /* Called without dev->lock held, and only in interrupt context. */ 45891acb21fSJeff Dike static void ubd_handler(void) 45991acb21fSJeff Dike { 4602adcec21SJeff Dike struct io_thread_req *req; 461a0044bdfSJeff Dike struct ubd *ubd; 462a0044bdfSJeff Dike struct list_head *list, *next_ele; 463a0044bdfSJeff Dike unsigned long flags; 46491acb21fSJeff Dike int n; 46509ace81cSJeff Dike 466a0044bdfSJeff Dike while(1){ 467a6ea4cceSJeff Dike n = os_read_file(thread_fd, &req, 4682adcec21SJeff Dike sizeof(struct io_thread_req *)); 46991acb21fSJeff Dike if(n != sizeof(req)){ 470a0044bdfSJeff Dike if(n == -EAGAIN) 471a0044bdfSJeff Dike break; 472a0044bdfSJeff Dike printk(KERN_ERR "spurious interrupt in ubd_handler, " 473a0044bdfSJeff Dike "err = %d\n", -n); 47491acb21fSJeff Dike return; 47591acb21fSJeff Dike } 47609ace81cSJeff Dike 4774d6c84d9STejun Heo blk_end_request(req->req, 0, req->length); 4782adcec21SJeff Dike kfree(req); 479a0044bdfSJeff Dike } 48091acb21fSJeff Dike reactivate_fd(thread_fd, UBD_IRQ); 481a0044bdfSJeff Dike 482a0044bdfSJeff Dike list_for_each_safe(list, next_ele, &restart){ 483a0044bdfSJeff Dike ubd = container_of(list, struct ubd, restart); 484a0044bdfSJeff Dike list_del_init(&ubd->restart); 485a0044bdfSJeff Dike spin_lock_irqsave(&ubd->lock, flags); 486a0044bdfSJeff Dike do_ubd_request(ubd->queue); 487a0044bdfSJeff Dike spin_unlock_irqrestore(&ubd->lock, flags); 488a0044bdfSJeff Dike } 48991acb21fSJeff Dike } 49009ace81cSJeff Dike 4917bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 4921da177e4SLinus Torvalds { 49391acb21fSJeff Dike ubd_handler(); 494dc764e50SJeff Dike return IRQ_HANDLED; 4951da177e4SLinus Torvalds } 4961da177e4SLinus Torvalds 49791acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 49891acb21fSJeff Dike static int io_pid = -1; 49991acb21fSJeff Dike 5005dc62b1bSWANG Cong static void kill_io_thread(void) 50191acb21fSJeff Dike { 50291acb21fSJeff Dike if(io_pid != -1) 50391acb21fSJeff Dike os_kill_process(io_pid, 1); 50491acb21fSJeff Dike } 50591acb21fSJeff Dike 50691acb21fSJeff Dike __uml_exitcall(kill_io_thread); 50791acb21fSJeff Dike 508d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5091da177e4SLinus Torvalds { 5101da177e4SLinus Torvalds char *file; 5111da177e4SLinus Torvalds 5127d314e34SPaolo 'Blaisorblade' Giarrusso file = ubd_dev->cow.file ? ubd_dev->cow.file : ubd_dev->file; 513dc764e50SJeff Dike return os_file_size(file, size_out); 5141da177e4SLinus Torvalds } 5151da177e4SLinus Torvalds 5165dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 5175dc62b1bSWANG Cong { 5185dc62b1bSWANG Cong int err; 5195dc62b1bSWANG Cong 5205dc62b1bSWANG Cong err = os_seek_file(fd, offset); 5215dc62b1bSWANG Cong if (err < 0) 5225dc62b1bSWANG Cong return err; 5235dc62b1bSWANG Cong 5245dc62b1bSWANG Cong err = os_read_file(fd, buf, len); 5255dc62b1bSWANG Cong if (err < 0) 5265dc62b1bSWANG Cong return err; 5275dc62b1bSWANG Cong 5285dc62b1bSWANG Cong return 0; 5295dc62b1bSWANG Cong } 5305dc62b1bSWANG Cong 5315dc62b1bSWANG Cong static int backing_file_mismatch(char *file, __u64 size, time_t mtime) 5325dc62b1bSWANG Cong { 5335dc62b1bSWANG Cong unsigned long modtime; 5345dc62b1bSWANG Cong unsigned long long actual; 5355dc62b1bSWANG Cong int err; 5365dc62b1bSWANG Cong 5375dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 5385dc62b1bSWANG Cong if (err < 0) { 5395dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 5405dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 5415dc62b1bSWANG Cong return err; 5425dc62b1bSWANG Cong } 5435dc62b1bSWANG Cong 5445dc62b1bSWANG Cong err = os_file_size(file, &actual); 5455dc62b1bSWANG Cong if (err < 0) { 5465dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 5475dc62b1bSWANG Cong "err = %d\n", file, -err); 5485dc62b1bSWANG Cong return err; 5495dc62b1bSWANG Cong } 5505dc62b1bSWANG Cong 5515dc62b1bSWANG Cong if (actual != size) { 5525dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 5535dc62b1bSWANG Cong * the typecast.*/ 5545dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 5555dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 5565dc62b1bSWANG Cong return -EINVAL; 5575dc62b1bSWANG Cong } 5585dc62b1bSWANG Cong if (modtime != mtime) { 5595dc62b1bSWANG Cong printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " 5605dc62b1bSWANG Cong "backing file\n", mtime, modtime); 5615dc62b1bSWANG Cong return -EINVAL; 5625dc62b1bSWANG Cong } 5635dc62b1bSWANG Cong return 0; 5645dc62b1bSWANG Cong } 5655dc62b1bSWANG Cong 5665dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 5675dc62b1bSWANG Cong { 5685dc62b1bSWANG Cong struct uml_stat buf1, buf2; 5695dc62b1bSWANG Cong int err; 5705dc62b1bSWANG Cong 5715dc62b1bSWANG Cong if (from_cmdline == NULL) 5725dc62b1bSWANG Cong return 0; 5735dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 5745dc62b1bSWANG Cong return 0; 5755dc62b1bSWANG Cong 5765dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 5775dc62b1bSWANG Cong if (err < 0) { 5785dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 5795dc62b1bSWANG Cong -err); 5805dc62b1bSWANG Cong return 0; 5815dc62b1bSWANG Cong } 5825dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 5835dc62b1bSWANG Cong if (err < 0) { 5845dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 5855dc62b1bSWANG Cong -err); 5865dc62b1bSWANG Cong return 1; 5875dc62b1bSWANG Cong } 5885dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 5895dc62b1bSWANG Cong return 0; 5905dc62b1bSWANG Cong 5915dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 5925dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 5935dc62b1bSWANG Cong from_cmdline, from_cow, cow); 5945dc62b1bSWANG Cong return 1; 5955dc62b1bSWANG Cong } 5965dc62b1bSWANG Cong 5975dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 5985dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 5995dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6005dc62b1bSWANG Cong int *create_cow_out) 6015dc62b1bSWANG Cong { 6025dc62b1bSWANG Cong time_t mtime; 6035dc62b1bSWANG Cong unsigned long long size; 6045dc62b1bSWANG Cong __u32 version, align; 6055dc62b1bSWANG Cong char *backing_file; 6065dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6075dc62b1bSWANG Cong 6085dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6095dc62b1bSWANG Cong if (fd < 0) { 6105dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6115dc62b1bSWANG Cong *create_cow_out = 1; 6125dc62b1bSWANG Cong if (!openflags->w || 6135dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 6145dc62b1bSWANG Cong return fd; 6155dc62b1bSWANG Cong openflags->w = 0; 6165dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6175dc62b1bSWANG Cong if (fd < 0) 6185dc62b1bSWANG Cong return fd; 6195dc62b1bSWANG Cong } 6205dc62b1bSWANG Cong 6215dc62b1bSWANG Cong if (shared) 6225dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 6235dc62b1bSWANG Cong else { 6245dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 6255dc62b1bSWANG Cong if (err < 0) { 6265dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 6275dc62b1bSWANG Cong file, -err); 6285dc62b1bSWANG Cong goto out_close; 6295dc62b1bSWANG Cong } 6305dc62b1bSWANG Cong } 6315dc62b1bSWANG Cong 6325dc62b1bSWANG Cong /* Successful return case! */ 6335dc62b1bSWANG Cong if (backing_file_out == NULL) 6345dc62b1bSWANG Cong return fd; 6355dc62b1bSWANG Cong 6365dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 6375dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 6385dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 6395dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 6405dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 6415dc62b1bSWANG Cong goto out_close; 6425dc62b1bSWANG Cong } 6435dc62b1bSWANG Cong if (err) 6445dc62b1bSWANG Cong return fd; 6455dc62b1bSWANG Cong 6465dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 6475dc62b1bSWANG Cong file); 6485dc62b1bSWANG Cong 6495dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 6505dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 6515dc62b1bSWANG Cong mtime)) { 6525dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 6535dc62b1bSWANG Cong *backing_file_out); 6545dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 6555dc62b1bSWANG Cong sectorsize, align, &size); 6565dc62b1bSWANG Cong if (err) { 6575dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 6585dc62b1bSWANG Cong goto out_close; 6595dc62b1bSWANG Cong } 6605dc62b1bSWANG Cong } else { 6615dc62b1bSWANG Cong *backing_file_out = backing_file; 6625dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 6635dc62b1bSWANG Cong if (err) 6645dc62b1bSWANG Cong goto out_close; 6655dc62b1bSWANG Cong } 6665dc62b1bSWANG Cong 6675dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 6685dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 6695dc62b1bSWANG Cong 6705dc62b1bSWANG Cong return fd; 6715dc62b1bSWANG Cong out_close: 6725dc62b1bSWANG Cong os_close_file(fd); 6735dc62b1bSWANG Cong return err; 6745dc62b1bSWANG Cong } 6755dc62b1bSWANG Cong 6765dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 6775dc62b1bSWANG Cong struct openflags flags, 6785dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 6795dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 6805dc62b1bSWANG Cong { 6815dc62b1bSWANG Cong int err, fd; 6825dc62b1bSWANG Cong 6835dc62b1bSWANG Cong flags.c = 1; 6845dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 6855dc62b1bSWANG Cong if (fd < 0) { 6865dc62b1bSWANG Cong err = fd; 6875dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 6885dc62b1bSWANG Cong cow_file, -err); 6895dc62b1bSWANG Cong goto out; 6905dc62b1bSWANG Cong } 6915dc62b1bSWANG Cong 6925dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 6935dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 6945dc62b1bSWANG Cong data_offset_out); 6955dc62b1bSWANG Cong if (!err) 6965dc62b1bSWANG Cong return fd; 6975dc62b1bSWANG Cong os_close_file(fd); 6985dc62b1bSWANG Cong out: 6995dc62b1bSWANG Cong return err; 7005dc62b1bSWANG Cong } 7015dc62b1bSWANG Cong 7025f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7031da177e4SLinus Torvalds { 7047d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7057d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7061da177e4SLinus Torvalds return; 7071da177e4SLinus Torvalds 7087d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7097d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7107d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7111da177e4SLinus Torvalds } 7121da177e4SLinus Torvalds 7137d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 7141da177e4SLinus Torvalds { 7151da177e4SLinus Torvalds struct openflags flags; 7161da177e4SLinus Torvalds char **back_ptr; 7171da177e4SLinus Torvalds int err, create_cow, *create_ptr; 7180bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 7191da177e4SLinus Torvalds 7207d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 7211da177e4SLinus Torvalds create_cow = 0; 7227d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 7237d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 7240bf16bffSPaolo 'Blaisorblade' Giarrusso 7250bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 7267d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 7277d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 7286c29256cSJeff Dike create_ptr); 7291da177e4SLinus Torvalds 7300bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 7310bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 7327d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags, 1 << 9, PAGE_SIZE, 7337d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 7347d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 7357d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 7360bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 7371da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 7387d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 7391da177e4SLinus Torvalds } 7401da177e4SLinus Torvalds } 7411da177e4SLinus Torvalds 7420bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 7437d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 7440bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 7450bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 7461da177e4SLinus Torvalds } 7470bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 7481da177e4SLinus Torvalds 7497d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 750086fa5ffSMartin K. Petersen blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); 751f4768ffdSJeff Dike 7521da177e4SLinus Torvalds err = -ENOMEM; 753da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 7547d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 7551da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 7561da177e4SLinus Torvalds goto error; 7571da177e4SLinus Torvalds } 7581da177e4SLinus Torvalds flush_tlb_kernel_vm(); 7591da177e4SLinus Torvalds 7607d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 7617d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 7627d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 7631da177e4SLinus Torvalds if(err < 0) 7641da177e4SLinus Torvalds goto error; 7651da177e4SLinus Torvalds 7667d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 7671da177e4SLinus Torvalds flags.w = 0; 7687d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 7696c29256cSJeff Dike NULL, NULL, NULL, NULL); 7701da177e4SLinus Torvalds if(err < 0) goto error; 7717d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 7721da177e4SLinus Torvalds } 773dc764e50SJeff Dike return 0; 7741da177e4SLinus Torvalds error: 7757d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 776dc764e50SJeff Dike return err; 7771da177e4SLinus Torvalds } 7781da177e4SLinus Torvalds 7792e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 7802e3f5251SJeff Dike { 7818691b97bSGreg Kroah-Hartman struct ubd *ubd_dev = dev_get_drvdata(dev); 7822e3f5251SJeff Dike 7832e3f5251SJeff Dike blk_cleanup_queue(ubd_dev->queue); 7842e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 7852e3f5251SJeff Dike } 7862e3f5251SJeff Dike 7875f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 7881da177e4SLinus Torvalds struct gendisk **disk_out) 7891da177e4SLinus Torvalds { 7901da177e4SLinus Torvalds struct gendisk *disk; 7911da177e4SLinus Torvalds 7921da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 7931da177e4SLinus Torvalds if(disk == NULL) 794dc764e50SJeff Dike return -ENOMEM; 7951da177e4SLinus Torvalds 7961da177e4SLinus Torvalds disk->major = major; 7971da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 7981da177e4SLinus Torvalds disk->fops = &ubd_blops; 7991da177e4SLinus Torvalds set_capacity(disk, size / 512); 800792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) 8011da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 802ce7b0f46SGreg Kroah-Hartman else 8031da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 8041da177e4SLinus Torvalds 8051da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 806792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) { 8077d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 8087d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 8092e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 8108691b97bSGreg Kroah-Hartman dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); 8117d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 8127d314e34SPaolo 'Blaisorblade' Giarrusso disk->driverfs_dev = &ubd_devs[unit].pdev.dev; 8131da177e4SLinus Torvalds } 8141da177e4SLinus Torvalds 8157d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 81662f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 8171da177e4SLinus Torvalds add_disk(disk); 8181da177e4SLinus Torvalds 8191da177e4SLinus Torvalds *disk_out = disk; 8201da177e4SLinus Torvalds return 0; 8211da177e4SLinus Torvalds } 8221da177e4SLinus Torvalds 8231da177e4SLinus Torvalds #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) 8241da177e4SLinus Torvalds 825f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 8261da177e4SLinus Torvalds { 8277d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 828f28169d2SJeff Dike int err = 0; 8291da177e4SLinus Torvalds 8307d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 831ec7cf783SJeff Dike goto out; 8321da177e4SLinus Torvalds 8337d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 834f28169d2SJeff Dike if(err < 0){ 835f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 83680c13749SJeff Dike goto out; 837f28169d2SJeff Dike } 8381da177e4SLinus Torvalds 8397d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 8401da177e4SLinus Torvalds 841a0044bdfSJeff Dike INIT_LIST_HEAD(&ubd_dev->restart); 8424f40c055SWANG Cong sg_init_table(ubd_dev->sg, MAX_SG); 843a0044bdfSJeff Dike 84462f96cb0SJeff Dike err = -ENOMEM; 84562f96cb0SJeff Dike ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); 84662f96cb0SJeff Dike if (ubd_dev->queue == NULL) { 84762f96cb0SJeff Dike *error_out = "Failed to initialize device queue"; 84880c13749SJeff Dike goto out; 84962f96cb0SJeff Dike } 85062f96cb0SJeff Dike ubd_dev->queue->queuedata = ubd_dev; 85162f96cb0SJeff Dike 852a0044bdfSJeff Dike blk_queue_max_hw_segments(ubd_dev->queue, MAX_SG); 853792dd4fcSChristoph Hellwig err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); 85462f96cb0SJeff Dike if(err){ 85562f96cb0SJeff Dike *error_out = "Failed to register device"; 85662f96cb0SJeff Dike goto out_cleanup; 85762f96cb0SJeff Dike } 8581da177e4SLinus Torvalds 859792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) 8605f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 8611da177e4SLinus Torvalds &fake_gendisk[n]); 8621da177e4SLinus Torvalds 86383380cc1SJeff Dike /* 86483380cc1SJeff Dike * Perhaps this should also be under the "if (fake_major)" above 86583380cc1SJeff Dike * using the fake_disk->disk_name 86683380cc1SJeff Dike */ 8671da177e4SLinus Torvalds if (fake_ide) 8681da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 8691da177e4SLinus Torvalds 870ec7cf783SJeff Dike err = 0; 871ec7cf783SJeff Dike out: 872ec7cf783SJeff Dike return err; 87362f96cb0SJeff Dike 87462f96cb0SJeff Dike out_cleanup: 87562f96cb0SJeff Dike blk_cleanup_queue(ubd_dev->queue); 87662f96cb0SJeff Dike goto out; 8771da177e4SLinus Torvalds } 8781da177e4SLinus Torvalds 879f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 8801da177e4SLinus Torvalds { 881e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 8821da177e4SLinus Torvalds 883f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 884f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 885f28169d2SJeff Dike * were set. 886f28169d2SJeff Dike */ 887970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 8881da177e4SLinus Torvalds if (str == NULL) { 889f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 890f28169d2SJeff Dike return -ENOMEM; 8911da177e4SLinus Torvalds } 892f28169d2SJeff Dike 893f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 894f28169d2SJeff Dike if (ret) 895e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 896f28169d2SJeff Dike 897e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 898e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 899d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 900e7f6552fSPaolo 'Blaisorblade' Giarrusso } 9011da177e4SLinus Torvalds 902d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 903f28169d2SJeff Dike ret = ubd_add(n, error_out); 904e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 9057d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 906d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 9071da177e4SLinus Torvalds 908e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 909e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 910e7f6552fSPaolo 'Blaisorblade' Giarrusso 911e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 912e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 913e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 9141da177e4SLinus Torvalds } 9151da177e4SLinus Torvalds 9161da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 9171da177e4SLinus Torvalds { 9187d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 9191da177e4SLinus Torvalds int n, len = 0; 9201da177e4SLinus Torvalds 9211da177e4SLinus Torvalds n = parse_unit(&name); 9221da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 9231da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 924dc764e50SJeff Dike return -1; 9251da177e4SLinus Torvalds } 9261da177e4SLinus Torvalds 9277d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 928d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 9291da177e4SLinus Torvalds 9307d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 9311da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 9321da177e4SLinus Torvalds goto out; 9331da177e4SLinus Torvalds } 9341da177e4SLinus Torvalds 9357d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 9361da177e4SLinus Torvalds 9377d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 9381da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 9397d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 9401da177e4SLinus Torvalds } 9411da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 9421da177e4SLinus Torvalds 9431da177e4SLinus Torvalds out: 944d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 945dc764e50SJeff Dike return len; 9461da177e4SLinus Torvalds } 9471da177e4SLinus Torvalds 94829d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 94929d56cfeSJeff Dike { 95029d56cfeSJeff Dike int n; 95129d56cfeSJeff Dike 95229d56cfeSJeff Dike n = parse_unit(str); 95329d56cfeSJeff Dike *start_out = 0; 95429d56cfeSJeff Dike *end_out = MAX_DEV - 1; 95529d56cfeSJeff Dike return n; 95629d56cfeSJeff Dike } 95729d56cfeSJeff Dike 958f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 9591da177e4SLinus Torvalds { 9602e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 9617d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 96229d56cfeSJeff Dike int err = -ENODEV; 9631da177e4SLinus Torvalds 964d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 9651da177e4SLinus Torvalds 9667d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 96729d56cfeSJeff Dike 9687d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 96929d56cfeSJeff Dike goto out; 97029d56cfeSJeff Dike 97129d56cfeSJeff Dike /* you cannot remove a open disk */ 97229d56cfeSJeff Dike err = -EBUSY; 9737d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 97429d56cfeSJeff Dike goto out; 97529d56cfeSJeff Dike 9761da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 977b47d2debSJeff Dike if(disk != NULL){ 978b47d2debSJeff Dike del_gendisk(disk); 979b47d2debSJeff Dike put_disk(disk); 980b47d2debSJeff Dike } 9811da177e4SLinus Torvalds 9821da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 9831da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 9841da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 9851da177e4SLinus Torvalds fake_gendisk[n] = NULL; 9861da177e4SLinus Torvalds } 9871da177e4SLinus Torvalds 9881da177e4SLinus Torvalds err = 0; 9892e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 9901da177e4SLinus Torvalds out: 991d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 99229d56cfeSJeff Dike return err; 9931da177e4SLinus Torvalds } 9941da177e4SLinus Torvalds 995f28169d2SJeff Dike /* All these are called by mconsole in process context and without 996b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 997f28169d2SJeff Dike */ 9981da177e4SLinus Torvalds static struct mc_device ubd_mc = { 99984f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 10001da177e4SLinus Torvalds .name = "ubd", 10011da177e4SLinus Torvalds .config = ubd_config, 10021da177e4SLinus Torvalds .get_config = ubd_get_config, 100329d56cfeSJeff Dike .id = ubd_id, 10041da177e4SLinus Torvalds .remove = ubd_remove, 10051da177e4SLinus Torvalds }; 10061da177e4SLinus Torvalds 1007d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 10081da177e4SLinus Torvalds { 10091da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 10101da177e4SLinus Torvalds return 0; 10111da177e4SLinus Torvalds } 10121da177e4SLinus Torvalds 10131da177e4SLinus Torvalds __initcall(ubd_mc_init); 10141da177e4SLinus Torvalds 1015d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1016d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1017d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1018d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1019b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1020d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1021d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1022b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1023b8831a1dSJeff Dike 1024dc764e50SJeff Dike return 0; 1025d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1026d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1027d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1028d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1029b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 10303ae5eaecSRussell King static struct platform_driver ubd_driver = { 10313ae5eaecSRussell King .driver = { 10321da177e4SLinus Torvalds .name = DRIVER_NAME, 10333ae5eaecSRussell King }, 10341da177e4SLinus Torvalds }; 10351da177e4SLinus Torvalds 1036d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 10371da177e4SLinus Torvalds { 1038f28169d2SJeff Dike char *error; 1039f28169d2SJeff Dike int i, err; 10401da177e4SLinus Torvalds 1041792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 10421da177e4SLinus Torvalds return -1; 10431da177e4SLinus Torvalds 1044792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 10451da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 10461da177e4SLinus Torvalds 10471da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 10481da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 10491da177e4SLinus Torvalds return -1; 10501da177e4SLinus Torvalds } 10513ae5eaecSRussell King platform_driver_register(&ubd_driver); 1052b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1053f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1054f28169d2SJeff Dike err = ubd_add(i, &error); 1055f28169d2SJeff Dike if(err) 1056f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1057f28169d2SJeff Dike "%s\n", i, error); 1058f28169d2SJeff Dike } 1059b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 10601da177e4SLinus Torvalds return 0; 10611da177e4SLinus Torvalds } 10621da177e4SLinus Torvalds 10631da177e4SLinus Torvalds late_initcall(ubd_init); 10641da177e4SLinus Torvalds 1065d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 106691acb21fSJeff Dike unsigned long stack; 106791acb21fSJeff Dike int err; 106891acb21fSJeff Dike 106991acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 107091acb21fSJeff Dike if(global_openflags.s){ 107191acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 107291acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 107391acb21fSJeff Dike * enough. So use anyway the io thread. */ 107491acb21fSJeff Dike } 107591acb21fSJeff Dike stack = alloc_stack(0, 0); 107691acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 107791acb21fSJeff Dike &thread_fd); 107891acb21fSJeff Dike if(io_pid < 0){ 107991acb21fSJeff Dike printk(KERN_ERR 108091acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 108191acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 108291acb21fSJeff Dike io_pid = -1; 1083dc764e50SJeff Dike return 0; 108491acb21fSJeff Dike } 108591acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 10867d314e34SPaolo 'Blaisorblade' Giarrusso IRQF_DISABLED, "ubd", ubd_devs); 108791acb21fSJeff Dike if(err != 0) 108891acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1089f4c57a78SJeff Dike return 0; 109091acb21fSJeff Dike } 109191acb21fSJeff Dike 109291acb21fSJeff Dike device_initcall(ubd_driver_init); 109391acb21fSJeff Dike 1094a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 10951da177e4SLinus Torvalds { 1096a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 10977d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 10981da177e4SLinus Torvalds int err = 0; 10991da177e4SLinus Torvalds 11007d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 11017d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 11021da177e4SLinus Torvalds if(err){ 11031da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 11047d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 11051da177e4SLinus Torvalds goto out; 11061da177e4SLinus Torvalds } 11071da177e4SLinus Torvalds } 11087d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 11097d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 11102c49be99SPaolo 'Blaisorblade' Giarrusso 11112c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 11122c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1113a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 11145f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 11151da177e4SLinus Torvalds err = -EROFS; 11162c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 11171da177e4SLinus Torvalds out: 1118dc764e50SJeff Dike return err; 11191da177e4SLinus Torvalds } 11201da177e4SLinus Torvalds 1121a625c998SAl Viro static int ubd_release(struct gendisk *disk, fmode_t mode) 11221da177e4SLinus Torvalds { 11237d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 11241da177e4SLinus Torvalds 11257d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 11265f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 1127dc764e50SJeff Dike return 0; 11281da177e4SLinus Torvalds } 11291da177e4SLinus Torvalds 113091acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 113191acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 113291acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 113391acb21fSJeff Dike __u64 bitmap_len) 11341da177e4SLinus Torvalds { 113591acb21fSJeff Dike __u64 sector = io_offset >> 9; 113691acb21fSJeff Dike int i, update_bitmap = 0; 11371da177e4SLinus Torvalds 113891acb21fSJeff Dike for(i = 0; i < length >> 9; i++){ 113991acb21fSJeff Dike if(cow_mask != NULL) 114091acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 114191acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 114209ace81cSJeff Dike continue; 11431da177e4SLinus Torvalds 114491acb21fSJeff Dike update_bitmap = 1; 114591acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 11461da177e4SLinus Torvalds } 114791acb21fSJeff Dike 114891acb21fSJeff Dike if(!update_bitmap) 114991acb21fSJeff Dike return; 115091acb21fSJeff Dike 115191acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 115291acb21fSJeff Dike 115391acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 115491acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 115591acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 115691acb21fSJeff Dike * for the original diagnosis. 115791acb21fSJeff Dike */ 11586d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 11596d074242SJiri Olsa sizeof(unsigned long)) - 1)) 116091acb21fSJeff Dike (*cow_offset)--; 116191acb21fSJeff Dike 116291acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 116391acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 116491acb21fSJeff Dike 116591acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 116691acb21fSJeff Dike *cow_offset += bitmap_offset; 116791acb21fSJeff Dike } 116891acb21fSJeff Dike 116991acb21fSJeff Dike static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, 117091acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 117191acb21fSJeff Dike { 117291acb21fSJeff Dike __u64 sector = req->offset >> 9; 117391acb21fSJeff Dike int i; 117491acb21fSJeff Dike 117591acb21fSJeff Dike if(req->length > (sizeof(req->sector_mask) * 8) << 9) 117691acb21fSJeff Dike panic("Operation too long"); 117791acb21fSJeff Dike 117891acb21fSJeff Dike if(req->op == UBD_READ) { 117991acb21fSJeff Dike for(i = 0; i < req->length >> 9; i++){ 118091acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 118191acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 118291acb21fSJeff Dike &req->sector_mask); 118391acb21fSJeff Dike } 118491acb21fSJeff Dike } 118591acb21fSJeff Dike else cowify_bitmap(req->offset, req->length, &req->sector_mask, 118691acb21fSJeff Dike &req->cow_offset, bitmap, bitmap_offset, 118791acb21fSJeff Dike req->bitmap_words, bitmap_len); 11881da177e4SLinus Torvalds } 11891da177e4SLinus Torvalds 119062f96cb0SJeff Dike /* Called with dev->lock held */ 1191a0044bdfSJeff Dike static void prepare_request(struct request *req, struct io_thread_req *io_req, 1192a0044bdfSJeff Dike unsigned long long offset, int page_offset, 1193a0044bdfSJeff Dike int len, struct page *page) 11941da177e4SLinus Torvalds { 11951da177e4SLinus Torvalds struct gendisk *disk = req->rq_disk; 11967d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 119791acb21fSJeff Dike 119862f96cb0SJeff Dike io_req->req = req; 1199a0044bdfSJeff Dike io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : 1200a0044bdfSJeff Dike ubd_dev->fd; 12017d314e34SPaolo 'Blaisorblade' Giarrusso io_req->fds[1] = ubd_dev->fd; 120291acb21fSJeff Dike io_req->cow_offset = -1; 12031da177e4SLinus Torvalds io_req->offset = offset; 12041da177e4SLinus Torvalds io_req->length = len; 12051da177e4SLinus Torvalds io_req->error = 0; 120691acb21fSJeff Dike io_req->sector_mask = 0; 120791acb21fSJeff Dike 120891acb21fSJeff Dike io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; 12091da177e4SLinus Torvalds io_req->offsets[0] = 0; 12107d314e34SPaolo 'Blaisorblade' Giarrusso io_req->offsets[1] = ubd_dev->cow.data_offset; 1211a0044bdfSJeff Dike io_req->buffer = page_address(page) + page_offset; 12121da177e4SLinus Torvalds io_req->sectorsize = 1 << 9; 12131da177e4SLinus Torvalds 12147d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL) 1215a0044bdfSJeff Dike cowify_req(io_req, ubd_dev->cow.bitmap, 1216a0044bdfSJeff Dike ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); 121791acb21fSJeff Dike 12181da177e4SLinus Torvalds } 12191da177e4SLinus Torvalds 122062f96cb0SJeff Dike /* Called with dev->lock held */ 1221165125e1SJens Axboe static void do_ubd_request(struct request_queue *q) 12221da177e4SLinus Torvalds { 12232adcec21SJeff Dike struct io_thread_req *io_req; 12241da177e4SLinus Torvalds struct request *req; 1225f81f2f7cSTejun Heo sector_t sector; 1226f81f2f7cSTejun Heo int n; 12271da177e4SLinus Torvalds 1228a0044bdfSJeff Dike while(1){ 12292a9529a0SJeff Dike struct ubd *dev = q->queuedata; 1230a0044bdfSJeff Dike if(dev->end_sg == 0){ 12319934c8c0STejun Heo struct request *req = blk_fetch_request(q); 1232a0044bdfSJeff Dike if(req == NULL) 123391acb21fSJeff Dike return; 1234a0044bdfSJeff Dike 1235a0044bdfSJeff Dike dev->request = req; 1236a0044bdfSJeff Dike dev->start_sg = 0; 1237a0044bdfSJeff Dike dev->end_sg = blk_rq_map_sg(q, req, dev->sg); 1238a0044bdfSJeff Dike } 1239a0044bdfSJeff Dike 1240a0044bdfSJeff Dike req = dev->request; 124183096ebfSTejun Heo sector = blk_rq_pos(req); 1242a0044bdfSJeff Dike while(dev->start_sg < dev->end_sg){ 1243a0044bdfSJeff Dike struct scatterlist *sg = &dev->sg[dev->start_sg]; 1244a0044bdfSJeff Dike 12452adcec21SJeff Dike io_req = kmalloc(sizeof(struct io_thread_req), 1246990c5587SPeter Zijlstra GFP_ATOMIC); 12472adcec21SJeff Dike if(io_req == NULL){ 12482adcec21SJeff Dike if(list_empty(&dev->restart)) 12492adcec21SJeff Dike list_add(&dev->restart, &restart); 12502adcec21SJeff Dike return; 12512adcec21SJeff Dike } 12522adcec21SJeff Dike prepare_request(req, io_req, 1253f81f2f7cSTejun Heo (unsigned long long)sector << 9, 125445711f1aSJens Axboe sg->offset, sg->length, sg_page(sg)); 1255a0044bdfSJeff Dike 1256f81f2f7cSTejun Heo sector += sg->length >> 9; 1257a6ea4cceSJeff Dike n = os_write_file(thread_fd, &io_req, 12582adcec21SJeff Dike sizeof(struct io_thread_req *)); 12592adcec21SJeff Dike if(n != sizeof(struct io_thread_req *)){ 1260a0044bdfSJeff Dike if(n != -EAGAIN) 126191acb21fSJeff Dike printk("write to io thread failed, " 126291acb21fSJeff Dike "errno = %d\n", -n); 1263a0044bdfSJeff Dike else if(list_empty(&dev->restart)) 1264a0044bdfSJeff Dike list_add(&dev->restart, &restart); 126512429bf9SMiklos Szeredi kfree(io_req); 1266a0044bdfSJeff Dike return; 126791acb21fSJeff Dike } 1268a0044bdfSJeff Dike 1269a0044bdfSJeff Dike dev->start_sg++; 1270a0044bdfSJeff Dike } 1271a0044bdfSJeff Dike dev->end_sg = 0; 1272a0044bdfSJeff Dike dev->request = NULL; 127391acb21fSJeff Dike } 12741da177e4SLinus Torvalds } 12751da177e4SLinus Torvalds 1276a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1277a885c8c4SChristoph Hellwig { 12787d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1279a885c8c4SChristoph Hellwig 1280a885c8c4SChristoph Hellwig geo->heads = 128; 1281a885c8c4SChristoph Hellwig geo->sectors = 32; 12827d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1283a885c8c4SChristoph Hellwig return 0; 1284a885c8c4SChristoph Hellwig } 1285a885c8c4SChristoph Hellwig 1286a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 12871da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 12881da177e4SLinus Torvalds { 1289a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 129073855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 12911da177e4SLinus Torvalds 12921da177e4SLinus Torvalds switch (cmd) { 12931da177e4SLinus Torvalds struct cdrom_volctrl volume; 12941da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 129573855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 129673855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 129773855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 129873855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 12991da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 13001da177e4SLinus Torvalds sizeof(ubd_id))) 1301dc764e50SJeff Dike return -EFAULT; 1302dc764e50SJeff Dike return 0; 13031da177e4SLinus Torvalds 13041da177e4SLinus Torvalds case CDROMVOLREAD: 13051da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1306dc764e50SJeff Dike return -EFAULT; 13071da177e4SLinus Torvalds volume.channel0 = 255; 13081da177e4SLinus Torvalds volume.channel1 = 255; 13091da177e4SLinus Torvalds volume.channel2 = 255; 13101da177e4SLinus Torvalds volume.channel3 = 255; 13111da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1312dc764e50SJeff Dike return -EFAULT; 1313dc764e50SJeff Dike return 0; 13141da177e4SLinus Torvalds } 1315dc764e50SJeff Dike return -EINVAL; 13161da177e4SLinus Torvalds } 13171da177e4SLinus Torvalds 131891acb21fSJeff Dike static int update_bitmap(struct io_thread_req *req) 13191da177e4SLinus Torvalds { 132091acb21fSJeff Dike int n; 132191acb21fSJeff Dike 132291acb21fSJeff Dike if(req->cow_offset == -1) 1323dc764e50SJeff Dike return 0; 132491acb21fSJeff Dike 132591acb21fSJeff Dike n = os_seek_file(req->fds[1], req->cow_offset); 132691acb21fSJeff Dike if(n < 0){ 132791acb21fSJeff Dike printk("do_io - bitmap lseek failed : err = %d\n", -n); 1328dc764e50SJeff Dike return 1; 132991acb21fSJeff Dike } 133091acb21fSJeff Dike 1331a6ea4cceSJeff Dike n = os_write_file(req->fds[1], &req->bitmap_words, 133291acb21fSJeff Dike sizeof(req->bitmap_words)); 133391acb21fSJeff Dike if(n != sizeof(req->bitmap_words)){ 133491acb21fSJeff Dike printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, 133591acb21fSJeff Dike req->fds[1]); 1336dc764e50SJeff Dike return 1; 133791acb21fSJeff Dike } 133891acb21fSJeff Dike 1339dc764e50SJeff Dike return 0; 134091acb21fSJeff Dike } 134191acb21fSJeff Dike 13425dc62b1bSWANG Cong static void do_io(struct io_thread_req *req) 134391acb21fSJeff Dike { 13441da177e4SLinus Torvalds char *buf; 134591acb21fSJeff Dike unsigned long len; 134691acb21fSJeff Dike int n, nsectors, start, end, bit; 134791acb21fSJeff Dike int err; 13481da177e4SLinus Torvalds __u64 off; 13491da177e4SLinus Torvalds 13501da177e4SLinus Torvalds nsectors = req->length / req->sectorsize; 13511da177e4SLinus Torvalds start = 0; 13521da177e4SLinus Torvalds do { 135391acb21fSJeff Dike bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); 13541da177e4SLinus Torvalds end = start; 13551da177e4SLinus Torvalds while((end < nsectors) && 135691acb21fSJeff Dike (ubd_test_bit(end, (unsigned char *) 135791acb21fSJeff Dike &req->sector_mask) == bit)) 13581da177e4SLinus Torvalds end++; 13591da177e4SLinus Torvalds 136091acb21fSJeff Dike off = req->offset + req->offsets[bit] + 13611da177e4SLinus Torvalds start * req->sectorsize; 13621da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 13631da177e4SLinus Torvalds buf = &req->buffer[start * req->sectorsize]; 13641da177e4SLinus Torvalds 136591acb21fSJeff Dike err = os_seek_file(req->fds[bit], off); 136691acb21fSJeff Dike if(err < 0){ 136791acb21fSJeff Dike printk("do_io - lseek failed : err = %d\n", -err); 13681da177e4SLinus Torvalds req->error = 1; 13691da177e4SLinus Torvalds return; 13701da177e4SLinus Torvalds } 137191acb21fSJeff Dike if(req->op == UBD_READ){ 137291acb21fSJeff Dike n = 0; 137391acb21fSJeff Dike do { 137491acb21fSJeff Dike buf = &buf[n]; 137591acb21fSJeff Dike len -= n; 1376a6ea4cceSJeff Dike n = os_read_file(req->fds[bit], buf, len); 137791acb21fSJeff Dike if (n < 0) { 137891acb21fSJeff Dike printk("do_io - read failed, err = %d " 137991acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 13801da177e4SLinus Torvalds req->error = 1; 13811da177e4SLinus Torvalds return; 13821da177e4SLinus Torvalds } 138391acb21fSJeff Dike } while((n < len) && (n != 0)); 138491acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 138591acb21fSJeff Dike } else { 1386a6ea4cceSJeff Dike n = os_write_file(req->fds[bit], buf, len); 138791acb21fSJeff Dike if(n != len){ 138891acb21fSJeff Dike printk("do_io - write failed err = %d " 138991acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 139091acb21fSJeff Dike req->error = 1; 139191acb21fSJeff Dike return; 139291acb21fSJeff Dike } 139391acb21fSJeff Dike } 13941da177e4SLinus Torvalds 13951da177e4SLinus Torvalds start = end; 13961da177e4SLinus Torvalds } while(start < nsectors); 139791acb21fSJeff Dike 139891acb21fSJeff Dike req->error = update_bitmap(req); 13991da177e4SLinus Torvalds } 140091acb21fSJeff Dike 140191acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 140291acb21fSJeff Dike * from ubd_init, which is an initcall. 140391acb21fSJeff Dike */ 140491acb21fSJeff Dike int kernel_fd = -1; 140591acb21fSJeff Dike 1406d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1407d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 140891acb21fSJeff Dike 140991acb21fSJeff Dike int io_thread(void *arg) 141091acb21fSJeff Dike { 14112adcec21SJeff Dike struct io_thread_req *req; 141291acb21fSJeff Dike int n; 141391acb21fSJeff Dike 141491acb21fSJeff Dike ignore_sigwinch_sig(); 141591acb21fSJeff Dike while(1){ 1416a6ea4cceSJeff Dike n = os_read_file(kernel_fd, &req, 14172adcec21SJeff Dike sizeof(struct io_thread_req *)); 14182adcec21SJeff Dike if(n != sizeof(struct io_thread_req *)){ 141991acb21fSJeff Dike if(n < 0) 142091acb21fSJeff Dike printk("io_thread - read failed, fd = %d, " 142191acb21fSJeff Dike "err = %d\n", kernel_fd, -n); 142291acb21fSJeff Dike else { 142391acb21fSJeff Dike printk("io_thread - short read, fd = %d, " 142491acb21fSJeff Dike "length = %d\n", kernel_fd, n); 142591acb21fSJeff Dike } 142691acb21fSJeff Dike continue; 142791acb21fSJeff Dike } 142891acb21fSJeff Dike io_count++; 14292adcec21SJeff Dike do_io(req); 1430a6ea4cceSJeff Dike n = os_write_file(kernel_fd, &req, 14312adcec21SJeff Dike sizeof(struct io_thread_req *)); 14322adcec21SJeff Dike if(n != sizeof(struct io_thread_req *)) 143391acb21fSJeff Dike printk("io_thread - write failed, fd = %d, err = %d\n", 143491acb21fSJeff Dike kernel_fd, -n); 143591acb21fSJeff Dike } 143691acb21fSJeff Dike 14371b57e9c2SJeff Dike return 0; 14381b57e9c2SJeff Dike } 1439