11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) 31da177e4SLinus Torvalds * Licensed under the GPL 41da177e4SLinus Torvalds */ 51da177e4SLinus Torvalds 61da177e4SLinus Torvalds /* 2001-09-28...2002-04-17 71da177e4SLinus Torvalds * Partition stuff by James_McMechan@hotmail.com 81da177e4SLinus Torvalds * old style ubd by setting UBD_SHIFT to 0 91da177e4SLinus Torvalds * 2002-09-27...2002-10-18 massive tinkering for 2.5 101da177e4SLinus Torvalds * partitions have changed in 2.5 111da177e4SLinus Torvalds * 2003-01-29 more tinkering for 2.5.59-1 121da177e4SLinus Torvalds * This should now address the sysfs problems and has 131da177e4SLinus Torvalds * the symlink for devfs to allow for booting with 141da177e4SLinus Torvalds * the common /dev/ubd/discX/... names rather than 151da177e4SLinus Torvalds * only /dev/ubdN/discN this version also has lots of 161da177e4SLinus Torvalds * clean ups preparing for ubd-many. 171da177e4SLinus Torvalds * James McMechan 181da177e4SLinus Torvalds */ 191da177e4SLinus Torvalds 201da177e4SLinus Torvalds #define MAJOR_NR UBD_MAJOR 211da177e4SLinus Torvalds #define UBD_SHIFT 4 221da177e4SLinus Torvalds 231da177e4SLinus Torvalds #include "linux/config.h" 241da177e4SLinus Torvalds #include "linux/module.h" 251da177e4SLinus Torvalds #include "linux/blkdev.h" 261da177e4SLinus Torvalds #include "linux/hdreg.h" 271da177e4SLinus Torvalds #include "linux/init.h" 281da177e4SLinus Torvalds #include "linux/devfs_fs_kernel.h" 291da177e4SLinus Torvalds #include "linux/cdrom.h" 301da177e4SLinus Torvalds #include "linux/proc_fs.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" 381da177e4SLinus Torvalds #include "asm/segment.h" 391da177e4SLinus Torvalds #include "asm/uaccess.h" 401da177e4SLinus Torvalds #include "asm/irq.h" 411da177e4SLinus Torvalds #include "asm/types.h" 421da177e4SLinus Torvalds #include "asm/tlbflush.h" 431da177e4SLinus Torvalds #include "user_util.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 "2_5compat.h" 531da177e4SLinus Torvalds #include "os.h" 541da177e4SLinus Torvalds #include "mem.h" 551da177e4SLinus Torvalds #include "mem_kern.h" 561da177e4SLinus Torvalds #include "cow.h" 571da177e4SLinus Torvalds 581da177e4SLinus Torvalds enum ubd_req { UBD_READ, UBD_WRITE, UBD_MMAP }; 591da177e4SLinus Torvalds 601da177e4SLinus Torvalds struct io_thread_req { 611da177e4SLinus Torvalds 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; 681da177e4SLinus Torvalds unsigned long sector_mask; 691da177e4SLinus Torvalds unsigned long long cow_offset; 701da177e4SLinus Torvalds unsigned long bitmap_words[2]; 711da177e4SLinus Torvalds int map_fd; 721da177e4SLinus Torvalds unsigned long long map_offset; 731da177e4SLinus Torvalds int error; 741da177e4SLinus Torvalds }; 751da177e4SLinus Torvalds 761da177e4SLinus Torvalds extern int open_ubd_file(char *file, struct openflags *openflags, 771da177e4SLinus Torvalds char **backing_file_out, int *bitmap_offset_out, 781da177e4SLinus Torvalds unsigned long *bitmap_len_out, int *data_offset_out, 791da177e4SLinus Torvalds int *create_cow_out); 801da177e4SLinus Torvalds extern int create_cow_file(char *cow_file, char *backing_file, 811da177e4SLinus Torvalds struct openflags flags, int sectorsize, 821da177e4SLinus Torvalds int alignment, int *bitmap_offset_out, 831da177e4SLinus Torvalds unsigned long *bitmap_len_out, 841da177e4SLinus Torvalds int *data_offset_out); 851da177e4SLinus Torvalds extern int read_cow_bitmap(int fd, void *buf, int offset, int len); 861da177e4SLinus Torvalds extern void do_io(struct io_thread_req *req); 871da177e4SLinus Torvalds 881da177e4SLinus Torvalds static inline int ubd_test_bit(__u64 bit, unsigned char *data) 891da177e4SLinus Torvalds { 901da177e4SLinus Torvalds __u64 n; 911da177e4SLinus Torvalds int bits, off; 921da177e4SLinus Torvalds 931da177e4SLinus Torvalds bits = sizeof(data[0]) * 8; 941da177e4SLinus Torvalds n = bit / bits; 951da177e4SLinus Torvalds off = bit % bits; 961da177e4SLinus Torvalds return((data[n] & (1 << off)) != 0); 971da177e4SLinus Torvalds } 981da177e4SLinus Torvalds 991da177e4SLinus Torvalds static inline void ubd_set_bit(__u64 bit, unsigned char *data) 1001da177e4SLinus Torvalds { 1011da177e4SLinus Torvalds __u64 n; 1021da177e4SLinus Torvalds int bits, off; 1031da177e4SLinus Torvalds 1041da177e4SLinus Torvalds bits = sizeof(data[0]) * 8; 1051da177e4SLinus Torvalds n = bit / bits; 1061da177e4SLinus Torvalds off = bit % bits; 1071da177e4SLinus Torvalds data[n] |= (1 << off); 1081da177e4SLinus Torvalds } 1091da177e4SLinus Torvalds /*End stuff from ubd_user.h*/ 1101da177e4SLinus Torvalds 1111da177e4SLinus Torvalds #define DRIVER_NAME "uml-blkdev" 1121da177e4SLinus Torvalds 1131da177e4SLinus Torvalds static DEFINE_SPINLOCK(ubd_io_lock); 1141da177e4SLinus Torvalds static DEFINE_SPINLOCK(ubd_lock); 1151da177e4SLinus Torvalds 1161da177e4SLinus Torvalds static void (*do_ubd)(void); 1171da177e4SLinus Torvalds 1181da177e4SLinus Torvalds static int ubd_open(struct inode * inode, struct file * filp); 1191da177e4SLinus Torvalds static int ubd_release(struct inode * inode, struct file * file); 1201da177e4SLinus Torvalds static int ubd_ioctl(struct inode * inode, struct file * file, 1211da177e4SLinus Torvalds unsigned int cmd, unsigned long arg); 1221da177e4SLinus Torvalds 1231da177e4SLinus Torvalds #define MAX_DEV (8) 1241da177e4SLinus Torvalds 1251da177e4SLinus Torvalds /* Changed in early boot */ 1261da177e4SLinus Torvalds static int ubd_do_mmap = 0; 1271da177e4SLinus Torvalds #define UBD_MMAP_BLOCK_SIZE PAGE_SIZE 1281da177e4SLinus Torvalds 1291da177e4SLinus Torvalds static struct block_device_operations ubd_blops = { 1301da177e4SLinus Torvalds .owner = THIS_MODULE, 1311da177e4SLinus Torvalds .open = ubd_open, 1321da177e4SLinus Torvalds .release = ubd_release, 1331da177e4SLinus Torvalds .ioctl = ubd_ioctl, 1341da177e4SLinus Torvalds }; 1351da177e4SLinus Torvalds 1361da177e4SLinus Torvalds /* Protected by the queue_lock */ 1371da177e4SLinus Torvalds static request_queue_t *ubd_queue; 1381da177e4SLinus Torvalds 1391da177e4SLinus Torvalds /* Protected by ubd_lock */ 1401da177e4SLinus Torvalds static int fake_major = MAJOR_NR; 1411da177e4SLinus Torvalds 1421da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1431da177e4SLinus Torvalds static struct gendisk *fake_gendisk[MAX_DEV]; 1441da177e4SLinus Torvalds 1451da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1461da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1471da177e4SLinus Torvalds .cl = 1 }) 1481da177e4SLinus Torvalds #else 1491da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1501da177e4SLinus Torvalds .cl = 1 }) 1511da177e4SLinus Torvalds #endif 1521da177e4SLinus Torvalds 1531da177e4SLinus Torvalds /* Not protected - changed only in ubd_setup_common and then only to 1541da177e4SLinus Torvalds * to enable O_SYNC. 1551da177e4SLinus Torvalds */ 1561da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1571da177e4SLinus Torvalds 1581da177e4SLinus Torvalds struct cow { 1591da177e4SLinus Torvalds char *file; 1601da177e4SLinus Torvalds int fd; 1611da177e4SLinus Torvalds unsigned long *bitmap; 1621da177e4SLinus Torvalds unsigned long bitmap_len; 1631da177e4SLinus Torvalds int bitmap_offset; 1641da177e4SLinus Torvalds int data_offset; 1651da177e4SLinus Torvalds }; 1661da177e4SLinus Torvalds 1671da177e4SLinus Torvalds struct ubd { 1681da177e4SLinus Torvalds char *file; 1691da177e4SLinus Torvalds int count; 1701da177e4SLinus Torvalds int fd; 1711da177e4SLinus Torvalds __u64 size; 1721da177e4SLinus Torvalds struct openflags boot_openflags; 1731da177e4SLinus Torvalds struct openflags openflags; 1741da177e4SLinus Torvalds int no_cow; 1751da177e4SLinus Torvalds struct cow cow; 1761da177e4SLinus Torvalds struct platform_device pdev; 1771da177e4SLinus Torvalds 1781da177e4SLinus Torvalds int map_writes; 1791da177e4SLinus Torvalds int map_reads; 1801da177e4SLinus Torvalds int nomap_writes; 1811da177e4SLinus Torvalds int nomap_reads; 1821da177e4SLinus Torvalds int write_maps; 1831da177e4SLinus Torvalds }; 1841da177e4SLinus Torvalds 1851da177e4SLinus Torvalds #define DEFAULT_COW { \ 1861da177e4SLinus Torvalds .file = NULL, \ 1871da177e4SLinus Torvalds .fd = -1, \ 1881da177e4SLinus Torvalds .bitmap = NULL, \ 1891da177e4SLinus Torvalds .bitmap_offset = 0, \ 1901da177e4SLinus Torvalds .data_offset = 0, \ 1911da177e4SLinus Torvalds } 1921da177e4SLinus Torvalds 1931da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1941da177e4SLinus Torvalds .file = NULL, \ 1951da177e4SLinus Torvalds .count = 0, \ 1961da177e4SLinus Torvalds .fd = -1, \ 1971da177e4SLinus Torvalds .size = -1, \ 1981da177e4SLinus Torvalds .boot_openflags = OPEN_FLAGS, \ 1991da177e4SLinus Torvalds .openflags = OPEN_FLAGS, \ 2001da177e4SLinus Torvalds .no_cow = 0, \ 2011da177e4SLinus Torvalds .cow = DEFAULT_COW, \ 2021da177e4SLinus Torvalds .map_writes = 0, \ 2031da177e4SLinus Torvalds .map_reads = 0, \ 2041da177e4SLinus Torvalds .nomap_writes = 0, \ 2051da177e4SLinus Torvalds .nomap_reads = 0, \ 2061da177e4SLinus Torvalds .write_maps = 0, \ 2071da177e4SLinus Torvalds } 2081da177e4SLinus Torvalds 2091da177e4SLinus Torvalds struct ubd ubd_dev[MAX_DEV] = { [ 0 ... MAX_DEV - 1 ] = DEFAULT_UBD }; 2101da177e4SLinus Torvalds 2111da177e4SLinus Torvalds static int ubd0_init(void) 2121da177e4SLinus Torvalds { 2131da177e4SLinus Torvalds struct ubd *dev = &ubd_dev[0]; 2141da177e4SLinus Torvalds 2151da177e4SLinus Torvalds if(dev->file == NULL) 2161da177e4SLinus Torvalds dev->file = "root_fs"; 2171da177e4SLinus Torvalds return(0); 2181da177e4SLinus Torvalds } 2191da177e4SLinus Torvalds 2201da177e4SLinus Torvalds __initcall(ubd0_init); 2211da177e4SLinus Torvalds 2221da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 2231da177e4SLinus Torvalds static int fake_ide = 0; 2241da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 2251da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 2261da177e4SLinus Torvalds 2271da177e4SLinus Torvalds static void make_proc_ide(void) 2281da177e4SLinus Torvalds { 2291da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 2301da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 2311da177e4SLinus Torvalds } 2321da177e4SLinus Torvalds 2331da177e4SLinus Torvalds static int proc_ide_read_media(char *page, char **start, off_t off, int count, 2341da177e4SLinus Torvalds int *eof, void *data) 2351da177e4SLinus Torvalds { 2361da177e4SLinus Torvalds int len; 2371da177e4SLinus Torvalds 2381da177e4SLinus Torvalds strcpy(page, "disk\n"); 2391da177e4SLinus Torvalds len = strlen("disk\n"); 2401da177e4SLinus Torvalds len -= off; 2411da177e4SLinus Torvalds if (len < count){ 2421da177e4SLinus Torvalds *eof = 1; 2431da177e4SLinus Torvalds if (len <= 0) return 0; 2441da177e4SLinus Torvalds } 2451da177e4SLinus Torvalds else len = count; 2461da177e4SLinus Torvalds *start = page + off; 2471da177e4SLinus Torvalds return len; 2481da177e4SLinus Torvalds } 2491da177e4SLinus Torvalds 2501da177e4SLinus Torvalds static void make_ide_entries(char *dev_name) 2511da177e4SLinus Torvalds { 2521da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2531da177e4SLinus Torvalds char name[64]; 2541da177e4SLinus Torvalds 2551da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2561da177e4SLinus Torvalds 2571da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2581da177e4SLinus Torvalds if(!dir) return; 2591da177e4SLinus Torvalds 2601da177e4SLinus Torvalds ent = create_proc_entry("media", S_IFREG|S_IRUGO, dir); 2611da177e4SLinus Torvalds if(!ent) return; 2621da177e4SLinus Torvalds ent->nlink = 1; 2631da177e4SLinus Torvalds ent->data = NULL; 2641da177e4SLinus Torvalds ent->read_proc = proc_ide_read_media; 2651da177e4SLinus Torvalds ent->write_proc = NULL; 2661da177e4SLinus Torvalds sprintf(name,"ide0/%s", dev_name); 2671da177e4SLinus Torvalds proc_symlink(dev_name, proc_ide_root, name); 2681da177e4SLinus Torvalds } 2691da177e4SLinus Torvalds 2701da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2711da177e4SLinus Torvalds { 2721da177e4SLinus Torvalds fake_ide = 1; 2731da177e4SLinus Torvalds return(1); 2741da177e4SLinus Torvalds } 2751da177e4SLinus Torvalds 2761da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2771da177e4SLinus Torvalds 2781da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2791da177e4SLinus Torvalds "fake_ide\n" 2801da177e4SLinus Torvalds " Create ide0 entries that map onto ubd devices.\n\n" 2811da177e4SLinus Torvalds ); 2821da177e4SLinus Torvalds 2831da177e4SLinus Torvalds static int parse_unit(char **ptr) 2841da177e4SLinus Torvalds { 2851da177e4SLinus Torvalds char *str = *ptr, *end; 2861da177e4SLinus Torvalds int n = -1; 2871da177e4SLinus Torvalds 2881da177e4SLinus Torvalds if(isdigit(*str)) { 2891da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2901da177e4SLinus Torvalds if(end == str) 2911da177e4SLinus Torvalds return(-1); 2921da177e4SLinus Torvalds *ptr = end; 2931da177e4SLinus Torvalds } 2941da177e4SLinus Torvalds else if (('a' <= *str) && (*str <= 'h')) { 2951da177e4SLinus Torvalds n = *str - 'a'; 2961da177e4SLinus Torvalds str++; 2971da177e4SLinus Torvalds *ptr = str; 2981da177e4SLinus Torvalds } 2991da177e4SLinus Torvalds return(n); 3001da177e4SLinus Torvalds } 3011da177e4SLinus Torvalds 3021da177e4SLinus Torvalds static int ubd_setup_common(char *str, int *index_out) 3031da177e4SLinus Torvalds { 3041da177e4SLinus Torvalds struct ubd *dev; 3051da177e4SLinus Torvalds struct openflags flags = global_openflags; 3061da177e4SLinus Torvalds char *backing_file; 3071da177e4SLinus Torvalds int n, err, i; 3081da177e4SLinus Torvalds 3091da177e4SLinus Torvalds if(index_out) *index_out = -1; 3101da177e4SLinus Torvalds n = *str; 3111da177e4SLinus Torvalds if(n == '='){ 3121da177e4SLinus Torvalds char *end; 3131da177e4SLinus Torvalds int major; 3141da177e4SLinus Torvalds 3151da177e4SLinus Torvalds str++; 3161da177e4SLinus Torvalds if(!strcmp(str, "mmap")){ 3171da177e4SLinus Torvalds CHOOSE_MODE(printk("mmap not supported by the ubd " 3181da177e4SLinus Torvalds "driver in tt mode\n"), 3191da177e4SLinus Torvalds ubd_do_mmap = 1); 3201da177e4SLinus Torvalds return(0); 3211da177e4SLinus Torvalds } 3221da177e4SLinus Torvalds 3231da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 3241da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 3251da177e4SLinus Torvalds return(0); 3261da177e4SLinus Torvalds } 3271da177e4SLinus Torvalds major = simple_strtoul(str, &end, 0); 3281da177e4SLinus Torvalds if((*end != '\0') || (end == str)){ 3291da177e4SLinus Torvalds printk(KERN_ERR 3301da177e4SLinus Torvalds "ubd_setup : didn't parse major number\n"); 3311da177e4SLinus Torvalds return(1); 3321da177e4SLinus Torvalds } 3331da177e4SLinus Torvalds 3341da177e4SLinus Torvalds err = 1; 3351da177e4SLinus Torvalds spin_lock(&ubd_lock); 3361da177e4SLinus Torvalds if(fake_major != MAJOR_NR){ 3371da177e4SLinus Torvalds printk(KERN_ERR "Can't assign a fake major twice\n"); 3381da177e4SLinus Torvalds goto out1; 3391da177e4SLinus Torvalds } 3401da177e4SLinus Torvalds 3411da177e4SLinus Torvalds fake_major = major; 3421da177e4SLinus Torvalds 3431da177e4SLinus Torvalds printk(KERN_INFO "Setting extra ubd major number to %d\n", 3441da177e4SLinus Torvalds major); 3451da177e4SLinus Torvalds err = 0; 3461da177e4SLinus Torvalds out1: 3471da177e4SLinus Torvalds spin_unlock(&ubd_lock); 3481da177e4SLinus Torvalds return(err); 3491da177e4SLinus Torvalds } 3501da177e4SLinus Torvalds 3511da177e4SLinus Torvalds n = parse_unit(&str); 3521da177e4SLinus Torvalds if(n < 0){ 3531da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : couldn't parse unit number " 3541da177e4SLinus Torvalds "'%s'\n", str); 3551da177e4SLinus Torvalds return(1); 3561da177e4SLinus Torvalds } 3571da177e4SLinus Torvalds if(n >= MAX_DEV){ 3581da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : index %d out of range " 3591da177e4SLinus Torvalds "(%d devices, from 0 to %d)\n", n, MAX_DEV, MAX_DEV - 1); 3601da177e4SLinus Torvalds return(1); 3611da177e4SLinus Torvalds } 3621da177e4SLinus Torvalds 3631da177e4SLinus Torvalds err = 1; 3641da177e4SLinus Torvalds spin_lock(&ubd_lock); 3651da177e4SLinus Torvalds 3661da177e4SLinus Torvalds dev = &ubd_dev[n]; 3671da177e4SLinus Torvalds if(dev->file != NULL){ 3681da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : device already configured\n"); 3691da177e4SLinus Torvalds goto out; 3701da177e4SLinus Torvalds } 3711da177e4SLinus Torvalds 3721da177e4SLinus Torvalds if (index_out) 3731da177e4SLinus Torvalds *index_out = n; 3741da177e4SLinus Torvalds 3751da177e4SLinus Torvalds for (i = 0; i < 4; i++) { 3761da177e4SLinus Torvalds switch (*str) { 3771da177e4SLinus Torvalds case 'r': 3781da177e4SLinus Torvalds flags.w = 0; 3791da177e4SLinus Torvalds break; 3801da177e4SLinus Torvalds case 's': 3811da177e4SLinus Torvalds flags.s = 1; 3821da177e4SLinus Torvalds break; 3831da177e4SLinus Torvalds case 'd': 3841da177e4SLinus Torvalds dev->no_cow = 1; 3851da177e4SLinus Torvalds break; 3861da177e4SLinus Torvalds case '=': 3871da177e4SLinus Torvalds str++; 3881da177e4SLinus Torvalds goto break_loop; 3891da177e4SLinus Torvalds default: 3901da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : Expected '=' or flag letter (r,s or d)\n"); 3911da177e4SLinus Torvalds goto out; 3921da177e4SLinus Torvalds } 3931da177e4SLinus Torvalds str++; 3941da177e4SLinus Torvalds } 3951da177e4SLinus Torvalds 3961da177e4SLinus Torvalds if (*str == '=') 3971da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : Too many flags specified\n"); 3981da177e4SLinus Torvalds else 3991da177e4SLinus Torvalds printk(KERN_ERR "ubd_setup : Expected '='\n"); 4001da177e4SLinus Torvalds goto out; 4011da177e4SLinus Torvalds 4021da177e4SLinus Torvalds break_loop: 4031da177e4SLinus Torvalds err = 0; 4041da177e4SLinus Torvalds backing_file = strchr(str, ','); 4051da177e4SLinus Torvalds 4061da177e4SLinus Torvalds if (!backing_file) { 4071da177e4SLinus Torvalds backing_file = strchr(str, ':'); 4081da177e4SLinus Torvalds } 4091da177e4SLinus Torvalds 4101da177e4SLinus Torvalds if(backing_file){ 4111da177e4SLinus Torvalds if(dev->no_cow) 4121da177e4SLinus Torvalds printk(KERN_ERR "Can't specify both 'd' and a " 4131da177e4SLinus Torvalds "cow file\n"); 4141da177e4SLinus Torvalds else { 4151da177e4SLinus Torvalds *backing_file = '\0'; 4161da177e4SLinus Torvalds backing_file++; 4171da177e4SLinus Torvalds } 4181da177e4SLinus Torvalds } 4191da177e4SLinus Torvalds dev->file = str; 4201da177e4SLinus Torvalds dev->cow.file = backing_file; 4211da177e4SLinus Torvalds dev->boot_openflags = flags; 4221da177e4SLinus Torvalds out: 4231da177e4SLinus Torvalds spin_unlock(&ubd_lock); 4241da177e4SLinus Torvalds return(err); 4251da177e4SLinus Torvalds } 4261da177e4SLinus Torvalds 4271da177e4SLinus Torvalds static int ubd_setup(char *str) 4281da177e4SLinus Torvalds { 4291da177e4SLinus Torvalds ubd_setup_common(str, NULL); 4301da177e4SLinus Torvalds return(1); 4311da177e4SLinus Torvalds } 4321da177e4SLinus Torvalds 4331da177e4SLinus Torvalds __setup("ubd", ubd_setup); 4341da177e4SLinus Torvalds __uml_help(ubd_setup, 4351da177e4SLinus Torvalds "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" 4361da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 4371da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 4381da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 4391da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 4401da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 4411da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 4421da177e4SLinus Torvalds " When using only one filename, UML will detect whether to thread it like\n" 4431da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 4441da177e4SLinus Torvalds " flag:\n" 4451da177e4SLinus Torvalds " ubd0d=BackingFile\n" 4461da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 4471da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 4481da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 4491da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 4501da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 4511da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 4521da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 4531da177e4SLinus Torvalds " an 's' will cause data to be written to disk on the host immediately.\n\n" 4541da177e4SLinus Torvalds ); 4551da177e4SLinus Torvalds 4561da177e4SLinus Torvalds static int udb_setup(char *str) 4571da177e4SLinus Torvalds { 4581da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 4591da177e4SLinus Torvalds "udb TYPO\n", str); 4601da177e4SLinus Torvalds return(1); 4611da177e4SLinus Torvalds } 4621da177e4SLinus Torvalds 4631da177e4SLinus Torvalds __setup("udb", udb_setup); 4641da177e4SLinus Torvalds __uml_help(udb_setup, 4651da177e4SLinus Torvalds "udb\n" 4661da177e4SLinus Torvalds " This option is here solely to catch ubd -> udb typos, which can be\n\n" 4671da177e4SLinus Torvalds " to impossible to catch visually unless you specifically look for\n\n" 4681da177e4SLinus Torvalds " them. The only result of any option starting with 'udb' is an error\n\n" 4691da177e4SLinus Torvalds " in the boot output.\n\n" 4701da177e4SLinus Torvalds ); 4711da177e4SLinus Torvalds 4721da177e4SLinus Torvalds static int fakehd_set = 0; 4731da177e4SLinus Torvalds static int fakehd(char *str) 4741da177e4SLinus Torvalds { 4751da177e4SLinus Torvalds printk(KERN_INFO "fakehd : Changing ubd name to \"hd\".\n"); 4761da177e4SLinus Torvalds fakehd_set = 1; 4771da177e4SLinus Torvalds return 1; 4781da177e4SLinus Torvalds } 4791da177e4SLinus Torvalds 4801da177e4SLinus Torvalds __setup("fakehd", fakehd); 4811da177e4SLinus Torvalds __uml_help(fakehd, 4821da177e4SLinus Torvalds "fakehd\n" 4831da177e4SLinus Torvalds " Change the ubd device name to \"hd\".\n\n" 4841da177e4SLinus Torvalds ); 4851da177e4SLinus Torvalds 4861da177e4SLinus Torvalds static void do_ubd_request(request_queue_t * q); 4871da177e4SLinus Torvalds 4881da177e4SLinus Torvalds /* Only changed by ubd_init, which is an initcall. */ 4891da177e4SLinus Torvalds int thread_fd = -1; 4901da177e4SLinus Torvalds 4911da177e4SLinus Torvalds /* Changed by ubd_handler, which is serialized because interrupts only 4921da177e4SLinus Torvalds * happen on CPU 0. 4931da177e4SLinus Torvalds */ 4941da177e4SLinus Torvalds int intr_count = 0; 4951da177e4SLinus Torvalds 4961da177e4SLinus Torvalds /* call ubd_finish if you need to serialize */ 4971da177e4SLinus Torvalds static void __ubd_finish(struct request *req, int error) 4981da177e4SLinus Torvalds { 4991da177e4SLinus Torvalds int nsect; 5001da177e4SLinus Torvalds 5011da177e4SLinus Torvalds if(error){ 5021da177e4SLinus Torvalds end_request(req, 0); 5031da177e4SLinus Torvalds return; 5041da177e4SLinus Torvalds } 5051da177e4SLinus Torvalds nsect = req->current_nr_sectors; 5061da177e4SLinus Torvalds req->sector += nsect; 5071da177e4SLinus Torvalds req->buffer += nsect << 9; 5081da177e4SLinus Torvalds req->errors = 0; 5091da177e4SLinus Torvalds req->nr_sectors -= nsect; 5101da177e4SLinus Torvalds req->current_nr_sectors = 0; 5111da177e4SLinus Torvalds end_request(req, 1); 5121da177e4SLinus Torvalds } 5131da177e4SLinus Torvalds 5141da177e4SLinus Torvalds static inline void ubd_finish(struct request *req, int error) 5151da177e4SLinus Torvalds { 5161da177e4SLinus Torvalds spin_lock(&ubd_io_lock); 5171da177e4SLinus Torvalds __ubd_finish(req, error); 5181da177e4SLinus Torvalds spin_unlock(&ubd_io_lock); 5191da177e4SLinus Torvalds } 5201da177e4SLinus Torvalds 5211da177e4SLinus Torvalds /* Called without ubd_io_lock held */ 5221da177e4SLinus Torvalds static void ubd_handler(void) 5231da177e4SLinus Torvalds { 5241da177e4SLinus Torvalds struct io_thread_req req; 5251da177e4SLinus Torvalds struct request *rq = elv_next_request(ubd_queue); 5261da177e4SLinus Torvalds int n, err; 5271da177e4SLinus Torvalds 5281da177e4SLinus Torvalds do_ubd = NULL; 5291da177e4SLinus Torvalds intr_count++; 5301da177e4SLinus Torvalds n = os_read_file(thread_fd, &req, sizeof(req)); 5311da177e4SLinus Torvalds if(n != sizeof(req)){ 5321da177e4SLinus Torvalds printk(KERN_ERR "Pid %d - spurious interrupt in ubd_handler, " 5331da177e4SLinus Torvalds "err = %d\n", os_getpid(), -n); 5341da177e4SLinus Torvalds spin_lock(&ubd_io_lock); 5351da177e4SLinus Torvalds end_request(rq, 0); 5361da177e4SLinus Torvalds spin_unlock(&ubd_io_lock); 5371da177e4SLinus Torvalds return; 5381da177e4SLinus Torvalds } 5391da177e4SLinus Torvalds 5401da177e4SLinus Torvalds if((req.op != UBD_MMAP) && 5411da177e4SLinus Torvalds ((req.offset != ((__u64) (rq->sector)) << 9) || 5421da177e4SLinus Torvalds (req.length != (rq->current_nr_sectors) << 9))) 5431da177e4SLinus Torvalds panic("I/O op mismatch"); 5441da177e4SLinus Torvalds 5451da177e4SLinus Torvalds if(req.map_fd != -1){ 5461da177e4SLinus Torvalds err = physmem_subst_mapping(req.buffer, req.map_fd, 5471da177e4SLinus Torvalds req.map_offset, 1); 5481da177e4SLinus Torvalds if(err) 5491da177e4SLinus Torvalds printk("ubd_handler - physmem_subst_mapping failed, " 5501da177e4SLinus Torvalds "err = %d\n", -err); 5511da177e4SLinus Torvalds } 5521da177e4SLinus Torvalds 5531da177e4SLinus Torvalds ubd_finish(rq, req.error); 5541da177e4SLinus Torvalds reactivate_fd(thread_fd, UBD_IRQ); 5551da177e4SLinus Torvalds do_ubd_request(ubd_queue); 5561da177e4SLinus Torvalds } 5571da177e4SLinus Torvalds 5581da177e4SLinus Torvalds static irqreturn_t ubd_intr(int irq, void *dev, struct pt_regs *unused) 5591da177e4SLinus Torvalds { 5601da177e4SLinus Torvalds ubd_handler(); 5611da177e4SLinus Torvalds return(IRQ_HANDLED); 5621da177e4SLinus Torvalds } 5631da177e4SLinus Torvalds 5641da177e4SLinus Torvalds /* Only changed by ubd_init, which is an initcall. */ 5651da177e4SLinus Torvalds static int io_pid = -1; 5661da177e4SLinus Torvalds 5671da177e4SLinus Torvalds void kill_io_thread(void) 5681da177e4SLinus Torvalds { 5691da177e4SLinus Torvalds if(io_pid != -1) 5701da177e4SLinus Torvalds os_kill_process(io_pid, 1); 5711da177e4SLinus Torvalds } 5721da177e4SLinus Torvalds 5731da177e4SLinus Torvalds __uml_exitcall(kill_io_thread); 5741da177e4SLinus Torvalds 5751da177e4SLinus Torvalds static int ubd_file_size(struct ubd *dev, __u64 *size_out) 5761da177e4SLinus Torvalds { 5771da177e4SLinus Torvalds char *file; 5781da177e4SLinus Torvalds 5791da177e4SLinus Torvalds file = dev->cow.file ? dev->cow.file : dev->file; 5801da177e4SLinus Torvalds return(os_file_size(file, size_out)); 5811da177e4SLinus Torvalds } 5821da177e4SLinus Torvalds 5831da177e4SLinus Torvalds static void ubd_close(struct ubd *dev) 5841da177e4SLinus Torvalds { 5851da177e4SLinus Torvalds if(ubd_do_mmap) 5861da177e4SLinus Torvalds physmem_forget_descriptor(dev->fd); 5871da177e4SLinus Torvalds os_close_file(dev->fd); 5881da177e4SLinus Torvalds if(dev->cow.file == NULL) 5891da177e4SLinus Torvalds return; 5901da177e4SLinus Torvalds 5911da177e4SLinus Torvalds if(ubd_do_mmap) 5921da177e4SLinus Torvalds physmem_forget_descriptor(dev->cow.fd); 5931da177e4SLinus Torvalds os_close_file(dev->cow.fd); 5941da177e4SLinus Torvalds vfree(dev->cow.bitmap); 5951da177e4SLinus Torvalds dev->cow.bitmap = NULL; 5961da177e4SLinus Torvalds } 5971da177e4SLinus Torvalds 5981da177e4SLinus Torvalds static int ubd_open_dev(struct ubd *dev) 5991da177e4SLinus Torvalds { 6001da177e4SLinus Torvalds struct openflags flags; 6011da177e4SLinus Torvalds char **back_ptr; 6021da177e4SLinus Torvalds int err, create_cow, *create_ptr; 6031da177e4SLinus Torvalds 6041da177e4SLinus Torvalds dev->openflags = dev->boot_openflags; 6051da177e4SLinus Torvalds create_cow = 0; 6061da177e4SLinus Torvalds create_ptr = (dev->cow.file != NULL) ? &create_cow : NULL; 6071da177e4SLinus Torvalds back_ptr = dev->no_cow ? NULL : &dev->cow.file; 6081da177e4SLinus Torvalds dev->fd = open_ubd_file(dev->file, &dev->openflags, back_ptr, 6091da177e4SLinus Torvalds &dev->cow.bitmap_offset, &dev->cow.bitmap_len, 6101da177e4SLinus Torvalds &dev->cow.data_offset, create_ptr); 6111da177e4SLinus Torvalds 6121da177e4SLinus Torvalds if((dev->fd == -ENOENT) && create_cow){ 6131da177e4SLinus Torvalds dev->fd = create_cow_file(dev->file, dev->cow.file, 6141da177e4SLinus Torvalds dev->openflags, 1 << 9, PAGE_SIZE, 6151da177e4SLinus Torvalds &dev->cow.bitmap_offset, 6161da177e4SLinus Torvalds &dev->cow.bitmap_len, 6171da177e4SLinus Torvalds &dev->cow.data_offset); 6181da177e4SLinus Torvalds if(dev->fd >= 0){ 6191da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 6201da177e4SLinus Torvalds "\"%s\"\n", dev->file, dev->cow.file); 6211da177e4SLinus Torvalds } 6221da177e4SLinus Torvalds } 6231da177e4SLinus Torvalds 6241da177e4SLinus Torvalds if(dev->fd < 0){ 6251da177e4SLinus Torvalds printk("Failed to open '%s', errno = %d\n", dev->file, 6261da177e4SLinus Torvalds -dev->fd); 6271da177e4SLinus Torvalds return(dev->fd); 6281da177e4SLinus Torvalds } 6291da177e4SLinus Torvalds 6301da177e4SLinus Torvalds if(dev->cow.file != NULL){ 6311da177e4SLinus Torvalds err = -ENOMEM; 6321da177e4SLinus Torvalds dev->cow.bitmap = (void *) vmalloc(dev->cow.bitmap_len); 6331da177e4SLinus Torvalds if(dev->cow.bitmap == NULL){ 6341da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 6351da177e4SLinus Torvalds goto error; 6361da177e4SLinus Torvalds } 6371da177e4SLinus Torvalds flush_tlb_kernel_vm(); 6381da177e4SLinus Torvalds 6391da177e4SLinus Torvalds err = read_cow_bitmap(dev->fd, dev->cow.bitmap, 6401da177e4SLinus Torvalds dev->cow.bitmap_offset, 6411da177e4SLinus Torvalds dev->cow.bitmap_len); 6421da177e4SLinus Torvalds if(err < 0) 6431da177e4SLinus Torvalds goto error; 6441da177e4SLinus Torvalds 6451da177e4SLinus Torvalds flags = dev->openflags; 6461da177e4SLinus Torvalds flags.w = 0; 6471da177e4SLinus Torvalds err = open_ubd_file(dev->cow.file, &flags, NULL, NULL, NULL, 6481da177e4SLinus Torvalds NULL, NULL); 6491da177e4SLinus Torvalds if(err < 0) goto error; 6501da177e4SLinus Torvalds dev->cow.fd = err; 6511da177e4SLinus Torvalds } 6521da177e4SLinus Torvalds return(0); 6531da177e4SLinus Torvalds error: 6541da177e4SLinus Torvalds os_close_file(dev->fd); 6551da177e4SLinus Torvalds return(err); 6561da177e4SLinus Torvalds } 6571da177e4SLinus Torvalds 6581da177e4SLinus Torvalds static int ubd_new_disk(int major, u64 size, int unit, 6591da177e4SLinus Torvalds struct gendisk **disk_out) 6601da177e4SLinus Torvalds 6611da177e4SLinus Torvalds { 6621da177e4SLinus Torvalds struct gendisk *disk; 6631da177e4SLinus Torvalds char from[sizeof("ubd/nnnnn\0")], to[sizeof("discnnnnn/disc\0")]; 6641da177e4SLinus Torvalds int err; 6651da177e4SLinus Torvalds 6661da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 6671da177e4SLinus Torvalds if(disk == NULL) 6681da177e4SLinus Torvalds return(-ENOMEM); 6691da177e4SLinus Torvalds 6701da177e4SLinus Torvalds disk->major = major; 6711da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 6721da177e4SLinus Torvalds disk->fops = &ubd_blops; 6731da177e4SLinus Torvalds set_capacity(disk, size / 512); 6741da177e4SLinus Torvalds if(major == MAJOR_NR){ 6751da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 6761da177e4SLinus Torvalds sprintf(disk->devfs_name, "ubd/disc%d", unit); 6771da177e4SLinus Torvalds sprintf(from, "ubd/%d", unit); 6781da177e4SLinus Torvalds sprintf(to, "disc%d/disc", unit); 6791da177e4SLinus Torvalds err = devfs_mk_symlink(from, to); 6801da177e4SLinus Torvalds if(err) 6811da177e4SLinus Torvalds printk("ubd_new_disk failed to make link from %s to " 6821da177e4SLinus Torvalds "%s, error = %d\n", from, to, err); 6831da177e4SLinus Torvalds } 6841da177e4SLinus Torvalds else { 6851da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 6861da177e4SLinus Torvalds sprintf(disk->devfs_name, "ubd_fake/disc%d", unit); 6871da177e4SLinus Torvalds } 6881da177e4SLinus Torvalds 6891da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 6901da177e4SLinus Torvalds if (major == MAJOR_NR) { 6911da177e4SLinus Torvalds ubd_dev[unit].pdev.id = unit; 6921da177e4SLinus Torvalds ubd_dev[unit].pdev.name = DRIVER_NAME; 6931da177e4SLinus Torvalds platform_device_register(&ubd_dev[unit].pdev); 6941da177e4SLinus Torvalds disk->driverfs_dev = &ubd_dev[unit].pdev.dev; 6951da177e4SLinus Torvalds } 6961da177e4SLinus Torvalds 6971da177e4SLinus Torvalds disk->private_data = &ubd_dev[unit]; 6981da177e4SLinus Torvalds disk->queue = ubd_queue; 6991da177e4SLinus Torvalds add_disk(disk); 7001da177e4SLinus Torvalds 7011da177e4SLinus Torvalds *disk_out = disk; 7021da177e4SLinus Torvalds return 0; 7031da177e4SLinus Torvalds } 7041da177e4SLinus Torvalds 7051da177e4SLinus Torvalds #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) 7061da177e4SLinus Torvalds 7071da177e4SLinus Torvalds static int ubd_add(int n) 7081da177e4SLinus Torvalds { 7091da177e4SLinus Torvalds struct ubd *dev = &ubd_dev[n]; 7101da177e4SLinus Torvalds int err; 7111da177e4SLinus Torvalds 7121da177e4SLinus Torvalds if(dev->file == NULL) 7131da177e4SLinus Torvalds return(-ENODEV); 7141da177e4SLinus Torvalds 7151da177e4SLinus Torvalds if (ubd_open_dev(dev)) 7161da177e4SLinus Torvalds return(-ENODEV); 7171da177e4SLinus Torvalds 7181da177e4SLinus Torvalds err = ubd_file_size(dev, &dev->size); 7191da177e4SLinus Torvalds if(err < 0) 7201da177e4SLinus Torvalds return(err); 7211da177e4SLinus Torvalds 7221da177e4SLinus Torvalds dev->size = ROUND_BLOCK(dev->size); 7231da177e4SLinus Torvalds 7241da177e4SLinus Torvalds err = ubd_new_disk(MAJOR_NR, dev->size, n, &ubd_gendisk[n]); 7251da177e4SLinus Torvalds if(err) 7261da177e4SLinus Torvalds return(err); 7271da177e4SLinus Torvalds 7281da177e4SLinus Torvalds if(fake_major != MAJOR_NR) 7291da177e4SLinus Torvalds ubd_new_disk(fake_major, dev->size, n, 7301da177e4SLinus Torvalds &fake_gendisk[n]); 7311da177e4SLinus Torvalds 7321da177e4SLinus Torvalds /* perhaps this should also be under the "if (fake_major)" above */ 7331da177e4SLinus Torvalds /* using the fake_disk->disk_name and also the fakehd_set name */ 7341da177e4SLinus Torvalds if (fake_ide) 7351da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 7361da177e4SLinus Torvalds 7371da177e4SLinus Torvalds ubd_close(dev); 7381da177e4SLinus Torvalds return 0; 7391da177e4SLinus Torvalds } 7401da177e4SLinus Torvalds 7411da177e4SLinus Torvalds static int ubd_config(char *str) 7421da177e4SLinus Torvalds { 7431da177e4SLinus Torvalds int n, err; 7441da177e4SLinus Torvalds 7451da177e4SLinus Torvalds str = uml_strdup(str); 7461da177e4SLinus Torvalds if(str == NULL){ 7471da177e4SLinus Torvalds printk(KERN_ERR "ubd_config failed to strdup string\n"); 7481da177e4SLinus Torvalds return(1); 7491da177e4SLinus Torvalds } 7501da177e4SLinus Torvalds err = ubd_setup_common(str, &n); 7511da177e4SLinus Torvalds if(err){ 7521da177e4SLinus Torvalds kfree(str); 7531da177e4SLinus Torvalds return(-1); 7541da177e4SLinus Torvalds } 7551da177e4SLinus Torvalds if(n == -1) return(0); 7561da177e4SLinus Torvalds 7571da177e4SLinus Torvalds spin_lock(&ubd_lock); 7581da177e4SLinus Torvalds err = ubd_add(n); 7591da177e4SLinus Torvalds if(err) 7601da177e4SLinus Torvalds ubd_dev[n].file = NULL; 7611da177e4SLinus Torvalds spin_unlock(&ubd_lock); 7621da177e4SLinus Torvalds 7631da177e4SLinus Torvalds return(err); 7641da177e4SLinus Torvalds } 7651da177e4SLinus Torvalds 7661da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 7671da177e4SLinus Torvalds { 7681da177e4SLinus Torvalds struct ubd *dev; 7691da177e4SLinus Torvalds int n, len = 0; 7701da177e4SLinus Torvalds 7711da177e4SLinus Torvalds n = parse_unit(&name); 7721da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 7731da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 7741da177e4SLinus Torvalds return(-1); 7751da177e4SLinus Torvalds } 7761da177e4SLinus Torvalds 7771da177e4SLinus Torvalds dev = &ubd_dev[n]; 7781da177e4SLinus Torvalds spin_lock(&ubd_lock); 7791da177e4SLinus Torvalds 7801da177e4SLinus Torvalds if(dev->file == NULL){ 7811da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 7821da177e4SLinus Torvalds goto out; 7831da177e4SLinus Torvalds } 7841da177e4SLinus Torvalds 7851da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, dev->file, 0); 7861da177e4SLinus Torvalds 7871da177e4SLinus Torvalds if(dev->cow.file != NULL){ 7881da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 7891da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, dev->cow.file, 1); 7901da177e4SLinus Torvalds } 7911da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 7921da177e4SLinus Torvalds 7931da177e4SLinus Torvalds out: 7941da177e4SLinus Torvalds spin_unlock(&ubd_lock); 7951da177e4SLinus Torvalds return(len); 7961da177e4SLinus Torvalds } 7971da177e4SLinus Torvalds 7981da177e4SLinus Torvalds static int ubd_remove(char *str) 7991da177e4SLinus Torvalds { 8001da177e4SLinus Torvalds struct ubd *dev; 8011da177e4SLinus Torvalds int n, err = -ENODEV; 8021da177e4SLinus Torvalds 8031da177e4SLinus Torvalds n = parse_unit(&str); 8041da177e4SLinus Torvalds 8051da177e4SLinus Torvalds if((n < 0) || (n >= MAX_DEV)) 8061da177e4SLinus Torvalds return(err); 8071da177e4SLinus Torvalds 8081da177e4SLinus Torvalds dev = &ubd_dev[n]; 8091da177e4SLinus Torvalds if(dev->count > 0) 8101da177e4SLinus Torvalds return(-EBUSY); /* you cannot remove a open disk */ 8111da177e4SLinus Torvalds 8121da177e4SLinus Torvalds err = 0; 8131da177e4SLinus Torvalds spin_lock(&ubd_lock); 8141da177e4SLinus Torvalds 8151da177e4SLinus Torvalds if(ubd_gendisk[n] == NULL) 8161da177e4SLinus Torvalds goto out; 8171da177e4SLinus Torvalds 8181da177e4SLinus Torvalds del_gendisk(ubd_gendisk[n]); 8191da177e4SLinus Torvalds put_disk(ubd_gendisk[n]); 8201da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 8211da177e4SLinus Torvalds 8221da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 8231da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 8241da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 8251da177e4SLinus Torvalds fake_gendisk[n] = NULL; 8261da177e4SLinus Torvalds } 8271da177e4SLinus Torvalds 8281da177e4SLinus Torvalds platform_device_unregister(&dev->pdev); 8291da177e4SLinus Torvalds *dev = ((struct ubd) DEFAULT_UBD); 8301da177e4SLinus Torvalds err = 0; 8311da177e4SLinus Torvalds out: 8321da177e4SLinus Torvalds spin_unlock(&ubd_lock); 8331da177e4SLinus Torvalds return(err); 8341da177e4SLinus Torvalds } 8351da177e4SLinus Torvalds 8361da177e4SLinus Torvalds static struct mc_device ubd_mc = { 8371da177e4SLinus Torvalds .name = "ubd", 8381da177e4SLinus Torvalds .config = ubd_config, 8391da177e4SLinus Torvalds .get_config = ubd_get_config, 8401da177e4SLinus Torvalds .remove = ubd_remove, 8411da177e4SLinus Torvalds }; 8421da177e4SLinus Torvalds 8431da177e4SLinus Torvalds static int ubd_mc_init(void) 8441da177e4SLinus Torvalds { 8451da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 8461da177e4SLinus Torvalds return 0; 8471da177e4SLinus Torvalds } 8481da177e4SLinus Torvalds 8491da177e4SLinus Torvalds __initcall(ubd_mc_init); 8501da177e4SLinus Torvalds 8511da177e4SLinus Torvalds static struct device_driver ubd_driver = { 8521da177e4SLinus Torvalds .name = DRIVER_NAME, 8531da177e4SLinus Torvalds .bus = &platform_bus_type, 8541da177e4SLinus Torvalds }; 8551da177e4SLinus Torvalds 8561da177e4SLinus Torvalds int ubd_init(void) 8571da177e4SLinus Torvalds { 8581da177e4SLinus Torvalds int i; 8591da177e4SLinus Torvalds 8601da177e4SLinus Torvalds devfs_mk_dir("ubd"); 8611da177e4SLinus Torvalds if (register_blkdev(MAJOR_NR, "ubd")) 8621da177e4SLinus Torvalds return -1; 8631da177e4SLinus Torvalds 8641da177e4SLinus Torvalds ubd_queue = blk_init_queue(do_ubd_request, &ubd_io_lock); 8651da177e4SLinus Torvalds if (!ubd_queue) { 8661da177e4SLinus Torvalds unregister_blkdev(MAJOR_NR, "ubd"); 8671da177e4SLinus Torvalds return -1; 8681da177e4SLinus Torvalds } 8691da177e4SLinus Torvalds 8701da177e4SLinus Torvalds if (fake_major != MAJOR_NR) { 8711da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 8721da177e4SLinus Torvalds 8731da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 8741da177e4SLinus Torvalds devfs_mk_dir(name); 8751da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 8761da177e4SLinus Torvalds return -1; 8771da177e4SLinus Torvalds } 8781da177e4SLinus Torvalds driver_register(&ubd_driver); 8791da177e4SLinus Torvalds for (i = 0; i < MAX_DEV; i++) 8801da177e4SLinus Torvalds ubd_add(i); 8811da177e4SLinus Torvalds return 0; 8821da177e4SLinus Torvalds } 8831da177e4SLinus Torvalds 8841da177e4SLinus Torvalds late_initcall(ubd_init); 8851da177e4SLinus Torvalds 8861da177e4SLinus Torvalds int ubd_driver_init(void){ 8871da177e4SLinus Torvalds unsigned long stack; 8881da177e4SLinus Torvalds int err; 8891da177e4SLinus Torvalds 8901da177e4SLinus Torvalds /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 8911da177e4SLinus Torvalds if(global_openflags.s){ 8921da177e4SLinus Torvalds printk(KERN_INFO "ubd: Synchronous mode\n"); 8931da177e4SLinus Torvalds /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 8941da177e4SLinus Torvalds * enough. So use anyway the io thread. */ 8951da177e4SLinus Torvalds } 8961da177e4SLinus Torvalds stack = alloc_stack(0, 0); 8971da177e4SLinus Torvalds io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 8981da177e4SLinus Torvalds &thread_fd); 8991da177e4SLinus Torvalds if(io_pid < 0){ 9001da177e4SLinus Torvalds printk(KERN_ERR 9011da177e4SLinus Torvalds "ubd : Failed to start I/O thread (errno = %d) - " 9021da177e4SLinus Torvalds "falling back to synchronous I/O\n", -io_pid); 9031da177e4SLinus Torvalds io_pid = -1; 9041da177e4SLinus Torvalds return(0); 9051da177e4SLinus Torvalds } 9061da177e4SLinus Torvalds err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 9071da177e4SLinus Torvalds SA_INTERRUPT, "ubd", ubd_dev); 9081da177e4SLinus Torvalds if(err != 0) 9091da177e4SLinus Torvalds printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 9101da177e4SLinus Torvalds return(err); 9111da177e4SLinus Torvalds } 9121da177e4SLinus Torvalds 9131da177e4SLinus Torvalds device_initcall(ubd_driver_init); 9141da177e4SLinus Torvalds 9151da177e4SLinus Torvalds static int ubd_open(struct inode *inode, struct file *filp) 9161da177e4SLinus Torvalds { 9171da177e4SLinus Torvalds struct gendisk *disk = inode->i_bdev->bd_disk; 9181da177e4SLinus Torvalds struct ubd *dev = disk->private_data; 9191da177e4SLinus Torvalds int err = 0; 9201da177e4SLinus Torvalds 9211da177e4SLinus Torvalds if(dev->count == 0){ 9221da177e4SLinus Torvalds err = ubd_open_dev(dev); 9231da177e4SLinus Torvalds if(err){ 9241da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 9251da177e4SLinus Torvalds disk->disk_name, dev->file, -err); 9261da177e4SLinus Torvalds goto out; 9271da177e4SLinus Torvalds } 9281da177e4SLinus Torvalds } 9291da177e4SLinus Torvalds dev->count++; 9301da177e4SLinus Torvalds if((filp->f_mode & FMODE_WRITE) && !dev->openflags.w){ 9311da177e4SLinus Torvalds if(--dev->count == 0) ubd_close(dev); 9321da177e4SLinus Torvalds err = -EROFS; 9331da177e4SLinus Torvalds } 9341da177e4SLinus Torvalds out: 9351da177e4SLinus Torvalds return(err); 9361da177e4SLinus Torvalds } 9371da177e4SLinus Torvalds 9381da177e4SLinus Torvalds static int ubd_release(struct inode * inode, struct file * file) 9391da177e4SLinus Torvalds { 9401da177e4SLinus Torvalds struct gendisk *disk = inode->i_bdev->bd_disk; 9411da177e4SLinus Torvalds struct ubd *dev = disk->private_data; 9421da177e4SLinus Torvalds 9431da177e4SLinus Torvalds if(--dev->count == 0) 9441da177e4SLinus Torvalds ubd_close(dev); 9451da177e4SLinus Torvalds return(0); 9461da177e4SLinus Torvalds } 9471da177e4SLinus Torvalds 9481da177e4SLinus Torvalds static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 9491da177e4SLinus Torvalds __u64 *cow_offset, unsigned long *bitmap, 9501da177e4SLinus Torvalds __u64 bitmap_offset, unsigned long *bitmap_words, 9511da177e4SLinus Torvalds __u64 bitmap_len) 9521da177e4SLinus Torvalds { 9531da177e4SLinus Torvalds __u64 sector = io_offset >> 9; 9541da177e4SLinus Torvalds int i, update_bitmap = 0; 9551da177e4SLinus Torvalds 9561da177e4SLinus Torvalds for(i = 0; i < length >> 9; i++){ 9571da177e4SLinus Torvalds if(cow_mask != NULL) 9581da177e4SLinus Torvalds ubd_set_bit(i, (unsigned char *) cow_mask); 9591da177e4SLinus Torvalds if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 9601da177e4SLinus Torvalds continue; 9611da177e4SLinus Torvalds 9621da177e4SLinus Torvalds update_bitmap = 1; 9631da177e4SLinus Torvalds ubd_set_bit(sector + i, (unsigned char *) bitmap); 9641da177e4SLinus Torvalds } 9651da177e4SLinus Torvalds 9661da177e4SLinus Torvalds if(!update_bitmap) 9671da177e4SLinus Torvalds return; 9681da177e4SLinus Torvalds 9691da177e4SLinus Torvalds *cow_offset = sector / (sizeof(unsigned long) * 8); 9701da177e4SLinus Torvalds 9711da177e4SLinus Torvalds /* This takes care of the case where we're exactly at the end of the 9721da177e4SLinus Torvalds * device, and *cow_offset + 1 is off the end. So, just back it up 9731da177e4SLinus Torvalds * by one word. Thanks to Lynn Kerby for the fix and James McMechan 9741da177e4SLinus Torvalds * for the original diagnosis. 9751da177e4SLinus Torvalds */ 9761da177e4SLinus Torvalds if(*cow_offset == ((bitmap_len + sizeof(unsigned long) - 1) / 9771da177e4SLinus Torvalds sizeof(unsigned long) - 1)) 9781da177e4SLinus Torvalds (*cow_offset)--; 9791da177e4SLinus Torvalds 9801da177e4SLinus Torvalds bitmap_words[0] = bitmap[*cow_offset]; 9811da177e4SLinus Torvalds bitmap_words[1] = bitmap[*cow_offset + 1]; 9821da177e4SLinus Torvalds 9831da177e4SLinus Torvalds *cow_offset *= sizeof(unsigned long); 9841da177e4SLinus Torvalds *cow_offset += bitmap_offset; 9851da177e4SLinus Torvalds } 9861da177e4SLinus Torvalds 9871da177e4SLinus Torvalds static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, 9881da177e4SLinus Torvalds __u64 bitmap_offset, __u64 bitmap_len) 9891da177e4SLinus Torvalds { 9901da177e4SLinus Torvalds __u64 sector = req->offset >> 9; 9911da177e4SLinus Torvalds int i; 9921da177e4SLinus Torvalds 9931da177e4SLinus Torvalds if(req->length > (sizeof(req->sector_mask) * 8) << 9) 9941da177e4SLinus Torvalds panic("Operation too long"); 9951da177e4SLinus Torvalds 9961da177e4SLinus Torvalds if(req->op == UBD_READ) { 9971da177e4SLinus Torvalds for(i = 0; i < req->length >> 9; i++){ 9981da177e4SLinus Torvalds if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 9991da177e4SLinus Torvalds ubd_set_bit(i, (unsigned char *) 10001da177e4SLinus Torvalds &req->sector_mask); 10011da177e4SLinus Torvalds } 10021da177e4SLinus Torvalds } 10031da177e4SLinus Torvalds else cowify_bitmap(req->offset, req->length, &req->sector_mask, 10041da177e4SLinus Torvalds &req->cow_offset, bitmap, bitmap_offset, 10051da177e4SLinus Torvalds req->bitmap_words, bitmap_len); 10061da177e4SLinus Torvalds } 10071da177e4SLinus Torvalds 10081da177e4SLinus Torvalds static int mmap_fd(struct request *req, struct ubd *dev, __u64 offset) 10091da177e4SLinus Torvalds { 10101da177e4SLinus Torvalds __u64 sector; 10111da177e4SLinus Torvalds unsigned char *bitmap; 10121da177e4SLinus Torvalds int bit, i; 10131da177e4SLinus Torvalds 10141da177e4SLinus Torvalds /* mmap must have been requested on the command line */ 10151da177e4SLinus Torvalds if(!ubd_do_mmap) 10161da177e4SLinus Torvalds return(-1); 10171da177e4SLinus Torvalds 10181da177e4SLinus Torvalds /* The buffer must be page aligned */ 10191da177e4SLinus Torvalds if(((unsigned long) req->buffer % UBD_MMAP_BLOCK_SIZE) != 0) 10201da177e4SLinus Torvalds return(-1); 10211da177e4SLinus Torvalds 10221da177e4SLinus Torvalds /* The request must be a page long */ 10231da177e4SLinus Torvalds if((req->current_nr_sectors << 9) != PAGE_SIZE) 10241da177e4SLinus Torvalds return(-1); 10251da177e4SLinus Torvalds 10261da177e4SLinus Torvalds if(dev->cow.file == NULL) 10271da177e4SLinus Torvalds return(dev->fd); 10281da177e4SLinus Torvalds 10291da177e4SLinus Torvalds sector = offset >> 9; 10301da177e4SLinus Torvalds bitmap = (unsigned char *) dev->cow.bitmap; 10311da177e4SLinus Torvalds bit = ubd_test_bit(sector, bitmap); 10321da177e4SLinus Torvalds 10331da177e4SLinus Torvalds for(i = 1; i < req->current_nr_sectors; i++){ 10341da177e4SLinus Torvalds if(ubd_test_bit(sector + i, bitmap) != bit) 10351da177e4SLinus Torvalds return(-1); 10361da177e4SLinus Torvalds } 10371da177e4SLinus Torvalds 10381da177e4SLinus Torvalds if(bit || (rq_data_dir(req) == WRITE)) 10391da177e4SLinus Torvalds offset += dev->cow.data_offset; 10401da177e4SLinus Torvalds 10411da177e4SLinus Torvalds /* The data on disk must be page aligned */ 10421da177e4SLinus Torvalds if((offset % UBD_MMAP_BLOCK_SIZE) != 0) 10431da177e4SLinus Torvalds return(-1); 10441da177e4SLinus Torvalds 10451da177e4SLinus Torvalds return(bit ? dev->fd : dev->cow.fd); 10461da177e4SLinus Torvalds } 10471da177e4SLinus Torvalds 10481da177e4SLinus Torvalds static int prepare_mmap_request(struct ubd *dev, int fd, __u64 offset, 10491da177e4SLinus Torvalds struct request *req, 10501da177e4SLinus Torvalds struct io_thread_req *io_req) 10511da177e4SLinus Torvalds { 10521da177e4SLinus Torvalds int err; 10531da177e4SLinus Torvalds 10541da177e4SLinus Torvalds if(rq_data_dir(req) == WRITE){ 10551da177e4SLinus Torvalds /* Writes are almost no-ops since the new data is already in the 10561da177e4SLinus Torvalds * host page cache 10571da177e4SLinus Torvalds */ 10581da177e4SLinus Torvalds dev->map_writes++; 10591da177e4SLinus Torvalds if(dev->cow.file != NULL) 10601da177e4SLinus Torvalds cowify_bitmap(io_req->offset, io_req->length, 10611da177e4SLinus Torvalds &io_req->sector_mask, &io_req->cow_offset, 10621da177e4SLinus Torvalds dev->cow.bitmap, dev->cow.bitmap_offset, 10631da177e4SLinus Torvalds io_req->bitmap_words, 10641da177e4SLinus Torvalds dev->cow.bitmap_len); 10651da177e4SLinus Torvalds } 10661da177e4SLinus Torvalds else { 10671da177e4SLinus Torvalds int w; 10681da177e4SLinus Torvalds 10691da177e4SLinus Torvalds if((dev->cow.file != NULL) && (fd == dev->cow.fd)) 10701da177e4SLinus Torvalds w = 0; 10711da177e4SLinus Torvalds else w = dev->openflags.w; 10721da177e4SLinus Torvalds 10731da177e4SLinus Torvalds if((dev->cow.file != NULL) && (fd == dev->fd)) 10741da177e4SLinus Torvalds offset += dev->cow.data_offset; 10751da177e4SLinus Torvalds 10761da177e4SLinus Torvalds err = physmem_subst_mapping(req->buffer, fd, offset, w); 10771da177e4SLinus Torvalds if(err){ 10781da177e4SLinus Torvalds printk("physmem_subst_mapping failed, err = %d\n", 10791da177e4SLinus Torvalds -err); 10801da177e4SLinus Torvalds return(1); 10811da177e4SLinus Torvalds } 10821da177e4SLinus Torvalds dev->map_reads++; 10831da177e4SLinus Torvalds } 10841da177e4SLinus Torvalds io_req->op = UBD_MMAP; 10851da177e4SLinus Torvalds io_req->buffer = req->buffer; 10861da177e4SLinus Torvalds return(0); 10871da177e4SLinus Torvalds } 10881da177e4SLinus Torvalds 10891da177e4SLinus Torvalds /* Called with ubd_io_lock held */ 10901da177e4SLinus Torvalds static int prepare_request(struct request *req, struct io_thread_req *io_req) 10911da177e4SLinus Torvalds { 10921da177e4SLinus Torvalds struct gendisk *disk = req->rq_disk; 10931da177e4SLinus Torvalds struct ubd *dev = disk->private_data; 10941da177e4SLinus Torvalds __u64 offset; 10951da177e4SLinus Torvalds int len, fd; 10961da177e4SLinus Torvalds 10971da177e4SLinus Torvalds if(req->rq_status == RQ_INACTIVE) return(1); 10981da177e4SLinus Torvalds 10991da177e4SLinus Torvalds if((rq_data_dir(req) == WRITE) && !dev->openflags.w){ 11001da177e4SLinus Torvalds printk("Write attempted on readonly ubd device %s\n", 11011da177e4SLinus Torvalds disk->disk_name); 11021da177e4SLinus Torvalds end_request(req, 0); 11031da177e4SLinus Torvalds return(1); 11041da177e4SLinus Torvalds } 11051da177e4SLinus Torvalds 11061da177e4SLinus Torvalds offset = ((__u64) req->sector) << 9; 11071da177e4SLinus Torvalds len = req->current_nr_sectors << 9; 11081da177e4SLinus Torvalds 11091da177e4SLinus Torvalds io_req->fds[0] = (dev->cow.file != NULL) ? dev->cow.fd : dev->fd; 11101da177e4SLinus Torvalds io_req->fds[1] = dev->fd; 11111da177e4SLinus Torvalds io_req->map_fd = -1; 11121da177e4SLinus Torvalds io_req->cow_offset = -1; 11131da177e4SLinus Torvalds io_req->offset = offset; 11141da177e4SLinus Torvalds io_req->length = len; 11151da177e4SLinus Torvalds io_req->error = 0; 11161da177e4SLinus Torvalds io_req->sector_mask = 0; 11171da177e4SLinus Torvalds 11181da177e4SLinus Torvalds fd = mmap_fd(req, dev, io_req->offset); 11191da177e4SLinus Torvalds if(fd > 0){ 11201da177e4SLinus Torvalds /* If mmapping is otherwise OK, but the first access to the 11211da177e4SLinus Torvalds * page is a write, then it's not mapped in yet. So we have 11221da177e4SLinus Torvalds * to write the data to disk first, then we can map the disk 11231da177e4SLinus Torvalds * page in and continue normally from there. 11241da177e4SLinus Torvalds */ 11251da177e4SLinus Torvalds if((rq_data_dir(req) == WRITE) && !is_remapped(req->buffer)){ 11261da177e4SLinus Torvalds io_req->map_fd = dev->fd; 11271da177e4SLinus Torvalds io_req->map_offset = io_req->offset + 11281da177e4SLinus Torvalds dev->cow.data_offset; 11291da177e4SLinus Torvalds dev->write_maps++; 11301da177e4SLinus Torvalds } 11311da177e4SLinus Torvalds else return(prepare_mmap_request(dev, fd, io_req->offset, req, 11321da177e4SLinus Torvalds io_req)); 11331da177e4SLinus Torvalds } 11341da177e4SLinus Torvalds 11351da177e4SLinus Torvalds if(rq_data_dir(req) == READ) 11361da177e4SLinus Torvalds dev->nomap_reads++; 11371da177e4SLinus Torvalds else dev->nomap_writes++; 11381da177e4SLinus Torvalds 11391da177e4SLinus Torvalds io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; 11401da177e4SLinus Torvalds io_req->offsets[0] = 0; 11411da177e4SLinus Torvalds io_req->offsets[1] = dev->cow.data_offset; 11421da177e4SLinus Torvalds io_req->buffer = req->buffer; 11431da177e4SLinus Torvalds io_req->sectorsize = 1 << 9; 11441da177e4SLinus Torvalds 11451da177e4SLinus Torvalds if(dev->cow.file != NULL) 11461da177e4SLinus Torvalds cowify_req(io_req, dev->cow.bitmap, dev->cow.bitmap_offset, 11471da177e4SLinus Torvalds dev->cow.bitmap_len); 11481da177e4SLinus Torvalds 11491da177e4SLinus Torvalds return(0); 11501da177e4SLinus Torvalds } 11511da177e4SLinus Torvalds 11521da177e4SLinus Torvalds /* Called with ubd_io_lock held */ 11531da177e4SLinus Torvalds static void do_ubd_request(request_queue_t *q) 11541da177e4SLinus Torvalds { 11551da177e4SLinus Torvalds struct io_thread_req io_req; 11561da177e4SLinus Torvalds struct request *req; 11571da177e4SLinus Torvalds int err, n; 11581da177e4SLinus Torvalds 11591da177e4SLinus Torvalds if(thread_fd == -1){ 11601da177e4SLinus Torvalds while((req = elv_next_request(q)) != NULL){ 11611da177e4SLinus Torvalds err = prepare_request(req, &io_req); 11621da177e4SLinus Torvalds if(!err){ 11631da177e4SLinus Torvalds do_io(&io_req); 11641da177e4SLinus Torvalds __ubd_finish(req, io_req.error); 11651da177e4SLinus Torvalds } 11661da177e4SLinus Torvalds } 11671da177e4SLinus Torvalds } 11681da177e4SLinus Torvalds else { 11691da177e4SLinus Torvalds if(do_ubd || (req = elv_next_request(q)) == NULL) 11701da177e4SLinus Torvalds return; 11711da177e4SLinus Torvalds err = prepare_request(req, &io_req); 11721da177e4SLinus Torvalds if(!err){ 11731da177e4SLinus Torvalds do_ubd = ubd_handler; 11741da177e4SLinus Torvalds n = os_write_file(thread_fd, (char *) &io_req, 11751da177e4SLinus Torvalds sizeof(io_req)); 11761da177e4SLinus Torvalds if(n != sizeof(io_req)) 11771da177e4SLinus Torvalds printk("write to io thread failed, " 11781da177e4SLinus Torvalds "errno = %d\n", -n); 11791da177e4SLinus Torvalds } 11801da177e4SLinus Torvalds } 11811da177e4SLinus Torvalds } 11821da177e4SLinus Torvalds 11831da177e4SLinus Torvalds static int ubd_ioctl(struct inode * inode, struct file * file, 11841da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 11851da177e4SLinus Torvalds { 11861da177e4SLinus Torvalds struct hd_geometry __user *loc = (struct hd_geometry __user *) arg; 11871da177e4SLinus Torvalds struct ubd *dev = inode->i_bdev->bd_disk->private_data; 11881da177e4SLinus Torvalds struct hd_driveid ubd_id = { 11891da177e4SLinus Torvalds .cyls = 0, 11901da177e4SLinus Torvalds .heads = 128, 11911da177e4SLinus Torvalds .sectors = 32, 11921da177e4SLinus Torvalds }; 11931da177e4SLinus Torvalds 11941da177e4SLinus Torvalds switch (cmd) { 11951da177e4SLinus Torvalds struct hd_geometry g; 11961da177e4SLinus Torvalds struct cdrom_volctrl volume; 11971da177e4SLinus Torvalds case HDIO_GETGEO: 11981da177e4SLinus Torvalds if(!loc) return(-EINVAL); 11991da177e4SLinus Torvalds g.heads = 128; 12001da177e4SLinus Torvalds g.sectors = 32; 12011da177e4SLinus Torvalds g.cylinders = dev->size / (128 * 32 * 512); 12021da177e4SLinus Torvalds g.start = get_start_sect(inode->i_bdev); 12031da177e4SLinus Torvalds return(copy_to_user(loc, &g, sizeof(g)) ? -EFAULT : 0); 12041da177e4SLinus Torvalds 12051da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 12061da177e4SLinus Torvalds ubd_id.cyls = dev->size / (128 * 32 * 512); 12071da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 12081da177e4SLinus Torvalds sizeof(ubd_id))) 12091da177e4SLinus Torvalds return(-EFAULT); 12101da177e4SLinus Torvalds return(0); 12111da177e4SLinus Torvalds 12121da177e4SLinus Torvalds case CDROMVOLREAD: 12131da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 12141da177e4SLinus Torvalds return(-EFAULT); 12151da177e4SLinus Torvalds volume.channel0 = 255; 12161da177e4SLinus Torvalds volume.channel1 = 255; 12171da177e4SLinus Torvalds volume.channel2 = 255; 12181da177e4SLinus Torvalds volume.channel3 = 255; 12191da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 12201da177e4SLinus Torvalds return(-EFAULT); 12211da177e4SLinus Torvalds return(0); 12221da177e4SLinus Torvalds } 12231da177e4SLinus Torvalds return(-EINVAL); 12241da177e4SLinus Torvalds } 12251da177e4SLinus Torvalds 12261da177e4SLinus Torvalds static int ubd_check_remapped(int fd, unsigned long address, int is_write, 12271da177e4SLinus Torvalds __u64 offset) 12281da177e4SLinus Torvalds { 12291da177e4SLinus Torvalds __u64 bitmap_offset; 12301da177e4SLinus Torvalds unsigned long new_bitmap[2]; 12311da177e4SLinus Torvalds int i, err, n; 12321da177e4SLinus Torvalds 12331da177e4SLinus Torvalds /* If it's not a write access, we can't do anything about it */ 12341da177e4SLinus Torvalds if(!is_write) 12351da177e4SLinus Torvalds return(0); 12361da177e4SLinus Torvalds 12371da177e4SLinus Torvalds /* We have a write */ 12381da177e4SLinus Torvalds for(i = 0; i < sizeof(ubd_dev) / sizeof(ubd_dev[0]); i++){ 12391da177e4SLinus Torvalds struct ubd *dev = &ubd_dev[i]; 12401da177e4SLinus Torvalds 12411da177e4SLinus Torvalds if((dev->fd != fd) && (dev->cow.fd != fd)) 12421da177e4SLinus Torvalds continue; 12431da177e4SLinus Torvalds 12441da177e4SLinus Torvalds /* It's a write to a ubd device */ 12451da177e4SLinus Torvalds 12461da177e4SLinus Torvalds if(!dev->openflags.w){ 12471da177e4SLinus Torvalds /* It's a write access on a read-only device - probably 12481da177e4SLinus Torvalds * shouldn't happen. If the kernel is trying to change 12491da177e4SLinus Torvalds * something with no intention of writing it back out, 12501da177e4SLinus Torvalds * then this message will clue us in that this needs 12511da177e4SLinus Torvalds * fixing 12521da177e4SLinus Torvalds */ 12531da177e4SLinus Torvalds printk("Write access to mapped page from readonly ubd " 12541da177e4SLinus Torvalds "device %d\n", i); 12551da177e4SLinus Torvalds return(0); 12561da177e4SLinus Torvalds } 12571da177e4SLinus Torvalds 12581da177e4SLinus Torvalds /* It's a write to a writeable ubd device - it must be COWed 12591da177e4SLinus Torvalds * because, otherwise, the page would have been mapped in 12601da177e4SLinus Torvalds * writeable 12611da177e4SLinus Torvalds */ 12621da177e4SLinus Torvalds 12631da177e4SLinus Torvalds if(!dev->cow.file) 12641da177e4SLinus Torvalds panic("Write fault on writeable non-COW ubd device %d", 12651da177e4SLinus Torvalds i); 12661da177e4SLinus Torvalds 12671da177e4SLinus Torvalds /* It should also be an access to the backing file since the 12681da177e4SLinus Torvalds * COW pages should be mapped in read-write 12691da177e4SLinus Torvalds */ 12701da177e4SLinus Torvalds 12711da177e4SLinus Torvalds if(fd == dev->fd) 12721da177e4SLinus Torvalds panic("Write fault on a backing page of ubd " 12731da177e4SLinus Torvalds "device %d\n", i); 12741da177e4SLinus Torvalds 12751da177e4SLinus Torvalds /* So, we do the write, copying the backing data to the COW 12761da177e4SLinus Torvalds * file... 12771da177e4SLinus Torvalds */ 12781da177e4SLinus Torvalds 12791da177e4SLinus Torvalds err = os_seek_file(dev->fd, offset + dev->cow.data_offset); 12801da177e4SLinus Torvalds if(err < 0) 12811da177e4SLinus Torvalds panic("Couldn't seek to %lld in COW file of ubd " 12821da177e4SLinus Torvalds "device %d, err = %d", 12831da177e4SLinus Torvalds offset + dev->cow.data_offset, i, -err); 12841da177e4SLinus Torvalds 12851da177e4SLinus Torvalds n = os_write_file(dev->fd, (void *) address, PAGE_SIZE); 12861da177e4SLinus Torvalds if(n != PAGE_SIZE) 12871da177e4SLinus Torvalds panic("Couldn't copy data to COW file of ubd " 12881da177e4SLinus Torvalds "device %d, err = %d", i, -n); 12891da177e4SLinus Torvalds 12901da177e4SLinus Torvalds /* ... updating the COW bitmap... */ 12911da177e4SLinus Torvalds 12921da177e4SLinus Torvalds cowify_bitmap(offset, PAGE_SIZE, NULL, &bitmap_offset, 12931da177e4SLinus Torvalds dev->cow.bitmap, dev->cow.bitmap_offset, 12941da177e4SLinus Torvalds new_bitmap, dev->cow.bitmap_len); 12951da177e4SLinus Torvalds 12961da177e4SLinus Torvalds err = os_seek_file(dev->fd, bitmap_offset); 12971da177e4SLinus Torvalds if(err < 0) 12981da177e4SLinus Torvalds panic("Couldn't seek to %lld in COW file of ubd " 12991da177e4SLinus Torvalds "device %d, err = %d", bitmap_offset, i, -err); 13001da177e4SLinus Torvalds 13011da177e4SLinus Torvalds n = os_write_file(dev->fd, new_bitmap, sizeof(new_bitmap)); 13021da177e4SLinus Torvalds if(n != sizeof(new_bitmap)) 13031da177e4SLinus Torvalds panic("Couldn't update bitmap of ubd device %d, " 13041da177e4SLinus Torvalds "err = %d", i, -n); 13051da177e4SLinus Torvalds 13061da177e4SLinus Torvalds /* Maybe we can map the COW page in, and maybe we can't. If 13071da177e4SLinus Torvalds * it is a pre-V3 COW file, we can't, since the alignment will 13081da177e4SLinus Torvalds * be wrong. If it is a V3 or later COW file which has been 13091da177e4SLinus Torvalds * moved to a system with a larger page size, then maybe we 13101da177e4SLinus Torvalds * can't, depending on the exact location of the page. 13111da177e4SLinus Torvalds */ 13121da177e4SLinus Torvalds 13131da177e4SLinus Torvalds offset += dev->cow.data_offset; 13141da177e4SLinus Torvalds 13151da177e4SLinus Torvalds /* Remove the remapping, putting the original anonymous page 13161da177e4SLinus Torvalds * back. If the COW file can be mapped in, that is done. 13171da177e4SLinus Torvalds * Otherwise, the COW page is read in. 13181da177e4SLinus Torvalds */ 13191da177e4SLinus Torvalds 13201da177e4SLinus Torvalds if(!physmem_remove_mapping((void *) address)) 13211da177e4SLinus Torvalds panic("Address 0x%lx not remapped by ubd device %d", 13221da177e4SLinus Torvalds address, i); 13231da177e4SLinus Torvalds if((offset % UBD_MMAP_BLOCK_SIZE) == 0) 13241da177e4SLinus Torvalds physmem_subst_mapping((void *) address, dev->fd, 13251da177e4SLinus Torvalds offset, 1); 13261da177e4SLinus Torvalds else { 13271da177e4SLinus Torvalds err = os_seek_file(dev->fd, offset); 13281da177e4SLinus Torvalds if(err < 0) 13291da177e4SLinus Torvalds panic("Couldn't seek to %lld in COW file of " 13301da177e4SLinus Torvalds "ubd device %d, err = %d", offset, i, 13311da177e4SLinus Torvalds -err); 13321da177e4SLinus Torvalds 13331da177e4SLinus Torvalds n = os_read_file(dev->fd, (void *) address, PAGE_SIZE); 13341da177e4SLinus Torvalds if(n != PAGE_SIZE) 13351da177e4SLinus Torvalds panic("Failed to read page from offset %llx of " 13361da177e4SLinus Torvalds "COW file of ubd device %d, err = %d", 13371da177e4SLinus Torvalds offset, i, -n); 13381da177e4SLinus Torvalds } 13391da177e4SLinus Torvalds 13401da177e4SLinus Torvalds return(1); 13411da177e4SLinus Torvalds } 13421da177e4SLinus Torvalds 13431da177e4SLinus Torvalds /* It's not a write on a ubd device */ 13441da177e4SLinus Torvalds return(0); 13451da177e4SLinus Torvalds } 13461da177e4SLinus Torvalds 13471da177e4SLinus Torvalds static struct remapper ubd_remapper = { 13481da177e4SLinus Torvalds .list = LIST_HEAD_INIT(ubd_remapper.list), 13491da177e4SLinus Torvalds .proc = ubd_check_remapped, 13501da177e4SLinus Torvalds }; 13511da177e4SLinus Torvalds 13521da177e4SLinus Torvalds static int ubd_remapper_setup(void) 13531da177e4SLinus Torvalds { 13541da177e4SLinus Torvalds if(ubd_do_mmap) 13551da177e4SLinus Torvalds register_remapper(&ubd_remapper); 13561da177e4SLinus Torvalds 13571da177e4SLinus Torvalds return(0); 13581da177e4SLinus Torvalds } 13591da177e4SLinus Torvalds 13601da177e4SLinus Torvalds __initcall(ubd_remapper_setup); 13611da177e4SLinus Torvalds 13621da177e4SLinus Torvalds static int same_backing_files(char *from_cmdline, char *from_cow, char *cow) 13631da177e4SLinus Torvalds { 13641da177e4SLinus Torvalds struct uml_stat buf1, buf2; 13651da177e4SLinus Torvalds int err; 13661da177e4SLinus Torvalds 13671da177e4SLinus Torvalds if(from_cmdline == NULL) return(1); 13681da177e4SLinus Torvalds if(!strcmp(from_cmdline, from_cow)) return(1); 13691da177e4SLinus Torvalds 13701da177e4SLinus Torvalds err = os_stat_file(from_cmdline, &buf1); 13711da177e4SLinus Torvalds if(err < 0){ 13721da177e4SLinus Torvalds printk("Couldn't stat '%s', err = %d\n", from_cmdline, -err); 13731da177e4SLinus Torvalds return(1); 13741da177e4SLinus Torvalds } 13751da177e4SLinus Torvalds err = os_stat_file(from_cow, &buf2); 13761da177e4SLinus Torvalds if(err < 0){ 13771da177e4SLinus Torvalds printk("Couldn't stat '%s', err = %d\n", from_cow, -err); 13781da177e4SLinus Torvalds return(1); 13791da177e4SLinus Torvalds } 13801da177e4SLinus Torvalds if((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 13811da177e4SLinus Torvalds return(1); 13821da177e4SLinus Torvalds 13831da177e4SLinus Torvalds printk("Backing file mismatch - \"%s\" requested,\n" 13841da177e4SLinus Torvalds "\"%s\" specified in COW header of \"%s\"\n", 13851da177e4SLinus Torvalds from_cmdline, from_cow, cow); 13861da177e4SLinus Torvalds return(0); 13871da177e4SLinus Torvalds } 13881da177e4SLinus Torvalds 13891da177e4SLinus Torvalds static int backing_file_mismatch(char *file, __u64 size, time_t mtime) 13901da177e4SLinus Torvalds { 13911da177e4SLinus Torvalds unsigned long modtime; 13921da177e4SLinus Torvalds long long actual; 13931da177e4SLinus Torvalds int err; 13941da177e4SLinus Torvalds 13951da177e4SLinus Torvalds err = os_file_modtime(file, &modtime); 13961da177e4SLinus Torvalds if(err < 0){ 13971da177e4SLinus Torvalds printk("Failed to get modification time of backing file " 13981da177e4SLinus Torvalds "\"%s\", err = %d\n", file, -err); 13991da177e4SLinus Torvalds return(err); 14001da177e4SLinus Torvalds } 14011da177e4SLinus Torvalds 14021da177e4SLinus Torvalds err = os_file_size(file, &actual); 14031da177e4SLinus Torvalds if(err < 0){ 14041da177e4SLinus Torvalds printk("Failed to get size of backing file \"%s\", " 14051da177e4SLinus Torvalds "err = %d\n", file, -err); 14061da177e4SLinus Torvalds return(err); 14071da177e4SLinus Torvalds } 14081da177e4SLinus Torvalds 14091da177e4SLinus Torvalds if(actual != size){ 14101da177e4SLinus Torvalds /*__u64 can be a long on AMD64 and with %lu GCC complains; so 14111da177e4SLinus Torvalds * the typecast.*/ 14121da177e4SLinus Torvalds printk("Size mismatch (%llu vs %llu) of COW header vs backing " 14131da177e4SLinus Torvalds "file\n", (unsigned long long) size, actual); 14141da177e4SLinus Torvalds return(-EINVAL); 14151da177e4SLinus Torvalds } 14161da177e4SLinus Torvalds if(modtime != mtime){ 14171da177e4SLinus Torvalds printk("mtime mismatch (%ld vs %ld) of COW header vs backing " 14181da177e4SLinus Torvalds "file\n", mtime, modtime); 14191da177e4SLinus Torvalds return(-EINVAL); 14201da177e4SLinus Torvalds } 14211da177e4SLinus Torvalds return(0); 14221da177e4SLinus Torvalds } 14231da177e4SLinus Torvalds 14241da177e4SLinus Torvalds int read_cow_bitmap(int fd, void *buf, int offset, int len) 14251da177e4SLinus Torvalds { 14261da177e4SLinus Torvalds int err; 14271da177e4SLinus Torvalds 14281da177e4SLinus Torvalds err = os_seek_file(fd, offset); 14291da177e4SLinus Torvalds if(err < 0) 14301da177e4SLinus Torvalds return(err); 14311da177e4SLinus Torvalds 14321da177e4SLinus Torvalds err = os_read_file(fd, buf, len); 14331da177e4SLinus Torvalds if(err < 0) 14341da177e4SLinus Torvalds return(err); 14351da177e4SLinus Torvalds 14361da177e4SLinus Torvalds return(0); 14371da177e4SLinus Torvalds } 14381da177e4SLinus Torvalds 14391da177e4SLinus Torvalds int open_ubd_file(char *file, struct openflags *openflags, 14401da177e4SLinus Torvalds char **backing_file_out, int *bitmap_offset_out, 14411da177e4SLinus Torvalds unsigned long *bitmap_len_out, int *data_offset_out, 14421da177e4SLinus Torvalds int *create_cow_out) 14431da177e4SLinus Torvalds { 14441da177e4SLinus Torvalds time_t mtime; 14451da177e4SLinus Torvalds unsigned long long size; 14461da177e4SLinus Torvalds __u32 version, align; 14471da177e4SLinus Torvalds char *backing_file; 14481da177e4SLinus Torvalds int fd, err, sectorsize, same, mode = 0644; 14491da177e4SLinus Torvalds 14501da177e4SLinus Torvalds fd = os_open_file(file, *openflags, mode); 14511da177e4SLinus Torvalds if(fd < 0){ 14521da177e4SLinus Torvalds if((fd == -ENOENT) && (create_cow_out != NULL)) 14531da177e4SLinus Torvalds *create_cow_out = 1; 14541da177e4SLinus Torvalds if(!openflags->w || 14551da177e4SLinus Torvalds ((fd != -EROFS) && (fd != -EACCES))) return(fd); 14561da177e4SLinus Torvalds openflags->w = 0; 14571da177e4SLinus Torvalds fd = os_open_file(file, *openflags, mode); 14581da177e4SLinus Torvalds if(fd < 0) 14591da177e4SLinus Torvalds return(fd); 14601da177e4SLinus Torvalds } 14611da177e4SLinus Torvalds 14621da177e4SLinus Torvalds err = os_lock_file(fd, openflags->w); 14631da177e4SLinus Torvalds if(err < 0){ 14641da177e4SLinus Torvalds printk("Failed to lock '%s', err = %d\n", file, -err); 14651da177e4SLinus Torvalds goto out_close; 14661da177e4SLinus Torvalds } 14671da177e4SLinus Torvalds 14681da177e4SLinus Torvalds if(backing_file_out == NULL) return(fd); 14691da177e4SLinus Torvalds 14701da177e4SLinus Torvalds err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 14711da177e4SLinus Torvalds &size, §orsize, &align, bitmap_offset_out); 14721da177e4SLinus Torvalds if(err && (*backing_file_out != NULL)){ 14731da177e4SLinus Torvalds printk("Failed to read COW header from COW file \"%s\", " 14741da177e4SLinus Torvalds "errno = %d\n", file, -err); 14751da177e4SLinus Torvalds goto out_close; 14761da177e4SLinus Torvalds } 14771da177e4SLinus Torvalds if(err) return(fd); 14781da177e4SLinus Torvalds 14791da177e4SLinus Torvalds if(backing_file_out == NULL) return(fd); 14801da177e4SLinus Torvalds 14811da177e4SLinus Torvalds same = same_backing_files(*backing_file_out, backing_file, file); 14821da177e4SLinus Torvalds 14831da177e4SLinus Torvalds if(!same && !backing_file_mismatch(*backing_file_out, size, mtime)){ 14841da177e4SLinus Torvalds printk("Switching backing file to '%s'\n", *backing_file_out); 14851da177e4SLinus Torvalds err = write_cow_header(file, fd, *backing_file_out, 14861da177e4SLinus Torvalds sectorsize, align, &size); 14871da177e4SLinus Torvalds if(err){ 14881da177e4SLinus Torvalds printk("Switch failed, errno = %d\n", -err); 14891da177e4SLinus Torvalds return(err); 14901da177e4SLinus Torvalds } 14911da177e4SLinus Torvalds } 14921da177e4SLinus Torvalds else { 14931da177e4SLinus Torvalds *backing_file_out = backing_file; 14941da177e4SLinus Torvalds err = backing_file_mismatch(*backing_file_out, size, mtime); 14951da177e4SLinus Torvalds if(err) goto out_close; 14961da177e4SLinus Torvalds } 14971da177e4SLinus Torvalds 14981da177e4SLinus Torvalds cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 14991da177e4SLinus Torvalds bitmap_len_out, data_offset_out); 15001da177e4SLinus Torvalds 15011da177e4SLinus Torvalds return(fd); 15021da177e4SLinus Torvalds out_close: 15031da177e4SLinus Torvalds os_close_file(fd); 15041da177e4SLinus Torvalds return(err); 15051da177e4SLinus Torvalds } 15061da177e4SLinus Torvalds 15071da177e4SLinus Torvalds int create_cow_file(char *cow_file, char *backing_file, struct openflags flags, 15081da177e4SLinus Torvalds int sectorsize, int alignment, int *bitmap_offset_out, 15091da177e4SLinus Torvalds unsigned long *bitmap_len_out, int *data_offset_out) 15101da177e4SLinus Torvalds { 15111da177e4SLinus Torvalds int err, fd; 15121da177e4SLinus Torvalds 15131da177e4SLinus Torvalds flags.c = 1; 15141da177e4SLinus Torvalds fd = open_ubd_file(cow_file, &flags, NULL, NULL, NULL, NULL, NULL); 15151da177e4SLinus Torvalds if(fd < 0){ 15161da177e4SLinus Torvalds err = fd; 15171da177e4SLinus Torvalds printk("Open of COW file '%s' failed, errno = %d\n", cow_file, 15181da177e4SLinus Torvalds -err); 15191da177e4SLinus Torvalds goto out; 15201da177e4SLinus Torvalds } 15211da177e4SLinus Torvalds 15221da177e4SLinus Torvalds err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 15231da177e4SLinus Torvalds bitmap_offset_out, bitmap_len_out, 15241da177e4SLinus Torvalds data_offset_out); 15251da177e4SLinus Torvalds if(!err) 15261da177e4SLinus Torvalds return(fd); 15271da177e4SLinus Torvalds os_close_file(fd); 15281da177e4SLinus Torvalds out: 15291da177e4SLinus Torvalds return(err); 15301da177e4SLinus Torvalds } 15311da177e4SLinus Torvalds 15321da177e4SLinus Torvalds static int update_bitmap(struct io_thread_req *req) 15331da177e4SLinus Torvalds { 15341da177e4SLinus Torvalds int n; 15351da177e4SLinus Torvalds 15361da177e4SLinus Torvalds if(req->cow_offset == -1) 15371da177e4SLinus Torvalds return(0); 15381da177e4SLinus Torvalds 15391da177e4SLinus Torvalds n = os_seek_file(req->fds[1], req->cow_offset); 15401da177e4SLinus Torvalds if(n < 0){ 15411da177e4SLinus Torvalds printk("do_io - bitmap lseek failed : err = %d\n", -n); 15421da177e4SLinus Torvalds return(1); 15431da177e4SLinus Torvalds } 15441da177e4SLinus Torvalds 15451da177e4SLinus Torvalds n = os_write_file(req->fds[1], &req->bitmap_words, 15461da177e4SLinus Torvalds sizeof(req->bitmap_words)); 15471da177e4SLinus Torvalds if(n != sizeof(req->bitmap_words)){ 15481da177e4SLinus Torvalds printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, 15491da177e4SLinus Torvalds req->fds[1]); 15501da177e4SLinus Torvalds return(1); 15511da177e4SLinus Torvalds } 15521da177e4SLinus Torvalds 15531da177e4SLinus Torvalds return(0); 15541da177e4SLinus Torvalds } 15551da177e4SLinus Torvalds 15561da177e4SLinus Torvalds void do_io(struct io_thread_req *req) 15571da177e4SLinus Torvalds { 15581da177e4SLinus Torvalds char *buf; 15591da177e4SLinus Torvalds unsigned long len; 15601da177e4SLinus Torvalds int n, nsectors, start, end, bit; 15611da177e4SLinus Torvalds int err; 15621da177e4SLinus Torvalds __u64 off; 15631da177e4SLinus Torvalds 15641da177e4SLinus Torvalds if(req->op == UBD_MMAP){ 15651da177e4SLinus Torvalds /* Touch the page to force the host to do any necessary IO to 15661da177e4SLinus Torvalds * get it into memory 15671da177e4SLinus Torvalds */ 15681da177e4SLinus Torvalds n = *((volatile int *) req->buffer); 15691da177e4SLinus Torvalds req->error = update_bitmap(req); 15701da177e4SLinus Torvalds return; 15711da177e4SLinus Torvalds } 15721da177e4SLinus Torvalds 15731da177e4SLinus Torvalds nsectors = req->length / req->sectorsize; 15741da177e4SLinus Torvalds start = 0; 15751da177e4SLinus Torvalds do { 15761da177e4SLinus Torvalds bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); 15771da177e4SLinus Torvalds end = start; 15781da177e4SLinus Torvalds while((end < nsectors) && 15791da177e4SLinus Torvalds (ubd_test_bit(end, (unsigned char *) 15801da177e4SLinus Torvalds &req->sector_mask) == bit)) 15811da177e4SLinus Torvalds end++; 15821da177e4SLinus Torvalds 15831da177e4SLinus Torvalds off = req->offset + req->offsets[bit] + 15841da177e4SLinus Torvalds start * req->sectorsize; 15851da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 15861da177e4SLinus Torvalds buf = &req->buffer[start * req->sectorsize]; 15871da177e4SLinus Torvalds 15881da177e4SLinus Torvalds err = os_seek_file(req->fds[bit], off); 15891da177e4SLinus Torvalds if(err < 0){ 15901da177e4SLinus Torvalds printk("do_io - lseek failed : err = %d\n", -err); 15911da177e4SLinus Torvalds req->error = 1; 15921da177e4SLinus Torvalds return; 15931da177e4SLinus Torvalds } 15941da177e4SLinus Torvalds if(req->op == UBD_READ){ 15951da177e4SLinus Torvalds n = 0; 15961da177e4SLinus Torvalds do { 15971da177e4SLinus Torvalds buf = &buf[n]; 15981da177e4SLinus Torvalds len -= n; 15991da177e4SLinus Torvalds n = os_read_file(req->fds[bit], buf, len); 16001da177e4SLinus Torvalds if (n < 0) { 16011da177e4SLinus Torvalds printk("do_io - read failed, err = %d " 16021da177e4SLinus Torvalds "fd = %d\n", -n, req->fds[bit]); 16031da177e4SLinus Torvalds req->error = 1; 16041da177e4SLinus Torvalds return; 16051da177e4SLinus Torvalds } 16061da177e4SLinus Torvalds } while((n < len) && (n != 0)); 16071da177e4SLinus Torvalds if (n < len) memset(&buf[n], 0, len - n); 16081da177e4SLinus Torvalds } 16091da177e4SLinus Torvalds else { 16101da177e4SLinus Torvalds n = os_write_file(req->fds[bit], buf, len); 16111da177e4SLinus Torvalds if(n != len){ 16121da177e4SLinus Torvalds printk("do_io - write failed err = %d " 16131da177e4SLinus Torvalds "fd = %d\n", -n, req->fds[bit]); 16141da177e4SLinus Torvalds req->error = 1; 16151da177e4SLinus Torvalds return; 16161da177e4SLinus Torvalds } 16171da177e4SLinus Torvalds } 16181da177e4SLinus Torvalds 16191da177e4SLinus Torvalds start = end; 16201da177e4SLinus Torvalds } while(start < nsectors); 16211da177e4SLinus Torvalds 16221da177e4SLinus Torvalds req->error = update_bitmap(req); 16231da177e4SLinus Torvalds } 16241da177e4SLinus Torvalds 16251da177e4SLinus Torvalds /* Changed in start_io_thread, which is serialized by being called only 16261da177e4SLinus Torvalds * from ubd_init, which is an initcall. 16271da177e4SLinus Torvalds */ 16281da177e4SLinus Torvalds int kernel_fd = -1; 16291da177e4SLinus Torvalds 16301da177e4SLinus Torvalds /* Only changed by the io thread */ 16311da177e4SLinus Torvalds int io_count = 0; 16321da177e4SLinus Torvalds 16331da177e4SLinus Torvalds int io_thread(void *arg) 16341da177e4SLinus Torvalds { 16351da177e4SLinus Torvalds struct io_thread_req req; 16361da177e4SLinus Torvalds int n; 16371da177e4SLinus Torvalds 16381da177e4SLinus Torvalds ignore_sigwinch_sig(); 16391da177e4SLinus Torvalds while(1){ 16401da177e4SLinus Torvalds n = os_read_file(kernel_fd, &req, sizeof(req)); 16411da177e4SLinus Torvalds if(n != sizeof(req)){ 16421da177e4SLinus Torvalds if(n < 0) 16431da177e4SLinus Torvalds printk("io_thread - read failed, fd = %d, " 16441da177e4SLinus Torvalds "err = %d\n", kernel_fd, -n); 16451da177e4SLinus Torvalds else { 16461da177e4SLinus Torvalds printk("io_thread - short read, fd = %d, " 16471da177e4SLinus Torvalds "length = %d\n", kernel_fd, n); 16481da177e4SLinus Torvalds } 16491da177e4SLinus Torvalds continue; 16501da177e4SLinus Torvalds } 16511da177e4SLinus Torvalds io_count++; 16521da177e4SLinus Torvalds do_io(&req); 16531da177e4SLinus Torvalds n = os_write_file(kernel_fd, &req, sizeof(req)); 16541da177e4SLinus Torvalds if(n != sizeof(req)) 16551da177e4SLinus Torvalds printk("io_thread - write failed, fd = %d, err = %d\n", 16561da177e4SLinus Torvalds kernel_fd, -n); 16571da177e4SLinus Torvalds } 16581da177e4SLinus Torvalds } 16591da177e4SLinus Torvalds 16601da177e4SLinus Torvalds /* 16611da177e4SLinus Torvalds * Overrides for Emacs so that we follow Linus's tabbing style. 16621da177e4SLinus Torvalds * Emacs will notice this stuff at the end of the file and automatically 16631da177e4SLinus Torvalds * adjust the settings for this buffer only. This must remain at the end 16641da177e4SLinus Torvalds * of the file. 16651da177e4SLinus Torvalds * --------------------------------------------------------------------------- 16661da177e4SLinus Torvalds * Local variables: 16671da177e4SLinus Torvalds * c-file-style: "linux" 16681da177e4SLinus Torvalds * End: 16691da177e4SLinus Torvalds */ 1670