11da177e4SLinus Torvalds /* 2f88f0bdfSAnton Ivanov * Copyright (C) 2015-2016 Anton Ivanov (aivanov@brocade.com) 31da177e4SLinus Torvalds * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) 41da177e4SLinus Torvalds * Licensed under the GPL 51da177e4SLinus Torvalds */ 61da177e4SLinus Torvalds 71da177e4SLinus Torvalds /* 2001-09-28...2002-04-17 81da177e4SLinus Torvalds * Partition stuff by James_McMechan@hotmail.com 91da177e4SLinus Torvalds * old style ubd by setting UBD_SHIFT to 0 101da177e4SLinus Torvalds * 2002-09-27...2002-10-18 massive tinkering for 2.5 111da177e4SLinus Torvalds * partitions have changed in 2.5 121da177e4SLinus Torvalds * 2003-01-29 more tinkering for 2.5.59-1 131da177e4SLinus Torvalds * This should now address the sysfs problems and has 141da177e4SLinus Torvalds * the symlink for devfs to allow for booting with 151da177e4SLinus Torvalds * the common /dev/ubd/discX/... names rather than 161da177e4SLinus Torvalds * only /dev/ubdN/discN this version also has lots of 171da177e4SLinus Torvalds * clean ups preparing for ubd-many. 181da177e4SLinus Torvalds * James McMechan 191da177e4SLinus Torvalds */ 201da177e4SLinus Torvalds 211da177e4SLinus Torvalds #define UBD_SHIFT 4 221da177e4SLinus Torvalds 238ea3c06aSAl Viro #include <linux/module.h> 248ea3c06aSAl Viro #include <linux/init.h> 258ea3c06aSAl Viro #include <linux/blkdev.h> 268ea3c06aSAl Viro #include <linux/ata.h> 278ea3c06aSAl Viro #include <linux/hdreg.h> 288ea3c06aSAl Viro #include <linux/cdrom.h> 298ea3c06aSAl Viro #include <linux/proc_fs.h> 308ea3c06aSAl Viro #include <linux/seq_file.h> 318ea3c06aSAl Viro #include <linux/ctype.h> 328ea3c06aSAl Viro #include <linux/slab.h> 338ea3c06aSAl Viro #include <linux/vmalloc.h> 348ea3c06aSAl Viro #include <linux/platform_device.h> 358ea3c06aSAl Viro #include <linux/scatterlist.h> 368ea3c06aSAl Viro #include <asm/tlbflush.h> 3737185b33SAl Viro #include <kern_util.h> 381da177e4SLinus Torvalds #include "mconsole_kern.h" 3937185b33SAl Viro #include <init.h> 4037185b33SAl Viro #include <irq_kern.h> 418ea3c06aSAl Viro #include "ubd.h" 4237185b33SAl Viro #include <os.h> 431da177e4SLinus Torvalds #include "cow.h" 441da177e4SLinus Torvalds 45805f11a0SRichard Weinberger enum ubd_req { UBD_READ, UBD_WRITE, UBD_FLUSH }; 461da177e4SLinus Torvalds 471da177e4SLinus Torvalds struct io_thread_req { 4862f96cb0SJeff Dike struct request *req; 4991acb21fSJeff Dike enum ubd_req op; 501da177e4SLinus Torvalds int fds[2]; 511da177e4SLinus Torvalds unsigned long offsets[2]; 521da177e4SLinus Torvalds unsigned long long offset; 531da177e4SLinus Torvalds unsigned long length; 541da177e4SLinus Torvalds char *buffer; 551da177e4SLinus Torvalds int sectorsize; 5691acb21fSJeff Dike unsigned long sector_mask; 5791acb21fSJeff Dike unsigned long long cow_offset; 5891acb21fSJeff Dike unsigned long bitmap_words[2]; 591da177e4SLinus Torvalds int error; 601da177e4SLinus Torvalds }; 611da177e4SLinus Torvalds 62f88f0bdfSAnton Ivanov 63f88f0bdfSAnton Ivanov static struct io_thread_req * (*irq_req_buffer)[]; 64f88f0bdfSAnton Ivanov static struct io_thread_req *irq_remainder; 65f88f0bdfSAnton Ivanov static int irq_remainder_size; 66f88f0bdfSAnton Ivanov 67f88f0bdfSAnton Ivanov static struct io_thread_req * (*io_req_buffer)[]; 68f88f0bdfSAnton Ivanov static struct io_thread_req *io_remainder; 69f88f0bdfSAnton Ivanov static int io_remainder_size; 70f88f0bdfSAnton Ivanov 71f88f0bdfSAnton Ivanov 72f88f0bdfSAnton Ivanov 7391acb21fSJeff Dike static inline int ubd_test_bit(__u64 bit, unsigned char *data) 741da177e4SLinus Torvalds { 751da177e4SLinus Torvalds __u64 n; 761da177e4SLinus Torvalds int bits, off; 771da177e4SLinus Torvalds 7891acb21fSJeff Dike bits = sizeof(data[0]) * 8; 791da177e4SLinus Torvalds n = bit / bits; 801da177e4SLinus Torvalds off = bit % bits; 81dc764e50SJeff Dike return (data[n] & (1 << off)) != 0; 821da177e4SLinus Torvalds } 831da177e4SLinus Torvalds 8491acb21fSJeff Dike static inline void ubd_set_bit(__u64 bit, unsigned char *data) 851da177e4SLinus Torvalds { 861da177e4SLinus Torvalds __u64 n; 871da177e4SLinus Torvalds int bits, off; 881da177e4SLinus Torvalds 8991acb21fSJeff Dike bits = sizeof(data[0]) * 8; 901da177e4SLinus Torvalds n = bit / bits; 911da177e4SLinus Torvalds off = bit % bits; 9291acb21fSJeff Dike data[n] |= (1 << off); 931da177e4SLinus Torvalds } 941da177e4SLinus Torvalds /*End stuff from ubd_user.h*/ 951da177e4SLinus Torvalds 961da177e4SLinus Torvalds #define DRIVER_NAME "uml-blkdev" 971da177e4SLinus Torvalds 98d7fb2c38SPaolo 'Blaisorblade' Giarrusso static DEFINE_MUTEX(ubd_lock); 999a181c58SArnd Bergmann static DEFINE_MUTEX(ubd_mutex); /* replaces BKL, might not be needed */ 1001da177e4SLinus Torvalds 101a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode); 102db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode); 103a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 1041da177e4SLinus Torvalds unsigned int cmd, unsigned long arg); 105a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); 1061da177e4SLinus Torvalds 10797d88ac8SPaolo 'Blaisorblade' Giarrusso #define MAX_DEV (16) 1081da177e4SLinus Torvalds 10983d5cde4SAlexey Dobriyan static const struct block_device_operations ubd_blops = { 1101da177e4SLinus Torvalds .owner = THIS_MODULE, 111a625c998SAl Viro .open = ubd_open, 112a625c998SAl Viro .release = ubd_release, 113a625c998SAl Viro .ioctl = ubd_ioctl, 114a885c8c4SChristoph Hellwig .getgeo = ubd_getgeo, 1151da177e4SLinus Torvalds }; 1161da177e4SLinus Torvalds 1171da177e4SLinus Torvalds /* Protected by ubd_lock */ 118792dd4fcSChristoph Hellwig static int fake_major = UBD_MAJOR; 1191da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1201da177e4SLinus Torvalds static struct gendisk *fake_gendisk[MAX_DEV]; 1211da177e4SLinus Torvalds 1221da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1231da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1241da177e4SLinus Torvalds .cl = 1 }) 1251da177e4SLinus Torvalds #else 1261da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1271da177e4SLinus Torvalds .cl = 1 }) 1281da177e4SLinus Torvalds #endif 1291da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1301da177e4SLinus Torvalds 1311da177e4SLinus Torvalds struct cow { 1322a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file name */ 1331da177e4SLinus Torvalds char *file; 1342a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file fd */ 1351da177e4SLinus Torvalds int fd; 1361da177e4SLinus Torvalds unsigned long *bitmap; 1371da177e4SLinus Torvalds unsigned long bitmap_len; 1381da177e4SLinus Torvalds int bitmap_offset; 1391da177e4SLinus Torvalds int data_offset; 1401da177e4SLinus Torvalds }; 1411da177e4SLinus Torvalds 142a0044bdfSJeff Dike #define MAX_SG 64 143a0044bdfSJeff Dike 1441da177e4SLinus Torvalds struct ubd { 145a0044bdfSJeff Dike struct list_head restart; 1462a9d32f6SPaolo 'Blaisorblade' Giarrusso /* name (and fd, below) of the file opened for writing, either the 1472a9d32f6SPaolo 'Blaisorblade' Giarrusso * backing or the cow file. */ 1481da177e4SLinus Torvalds char *file; 1491da177e4SLinus Torvalds int count; 1501da177e4SLinus Torvalds int fd; 1511da177e4SLinus Torvalds __u64 size; 1521da177e4SLinus Torvalds struct openflags boot_openflags; 1531da177e4SLinus Torvalds struct openflags openflags; 15484e945e3SPaolo 'Blaisorblade' Giarrusso unsigned shared:1; 15584e945e3SPaolo 'Blaisorblade' Giarrusso unsigned no_cow:1; 1561da177e4SLinus Torvalds struct cow cow; 1571da177e4SLinus Torvalds struct platform_device pdev; 15862f96cb0SJeff Dike struct request_queue *queue; 15962f96cb0SJeff Dike spinlock_t lock; 160a0044bdfSJeff Dike struct scatterlist sg[MAX_SG]; 161a0044bdfSJeff Dike struct request *request; 162a0044bdfSJeff Dike int start_sg, end_sg; 16347526903STejun Heo sector_t rq_pos; 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, \ 18422e65004SThomas Gleixner .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \ 185a0044bdfSJeff Dike .request = NULL, \ 186a0044bdfSJeff Dike .start_sg = 0, \ 187a0044bdfSJeff Dike .end_sg = 0, \ 18847526903STejun Heo .rq_pos = 0, \ 1891da177e4SLinus Torvalds } 1901da177e4SLinus Torvalds 191b8831a1dSJeff Dike /* Protected by ubd_lock */ 1925dc62b1bSWANG Cong static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; 1931da177e4SLinus Torvalds 1941da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 1951da177e4SLinus Torvalds static int fake_ide = 0; 1961da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 1971da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 1981da177e4SLinus Torvalds 1991da177e4SLinus Torvalds static void make_proc_ide(void) 2001da177e4SLinus Torvalds { 2011da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 2021da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 2031da177e4SLinus Torvalds } 2041da177e4SLinus Torvalds 2056613c5e8SAlexey Dobriyan static int fake_ide_media_proc_show(struct seq_file *m, void *v) 2061da177e4SLinus Torvalds { 2076613c5e8SAlexey Dobriyan seq_puts(m, "disk\n"); 2086613c5e8SAlexey Dobriyan return 0; 2096613c5e8SAlexey Dobriyan } 2101da177e4SLinus Torvalds 2116613c5e8SAlexey Dobriyan static int fake_ide_media_proc_open(struct inode *inode, struct file *file) 2126613c5e8SAlexey Dobriyan { 2136613c5e8SAlexey Dobriyan return single_open(file, fake_ide_media_proc_show, NULL); 2141da177e4SLinus Torvalds } 2156613c5e8SAlexey Dobriyan 2166613c5e8SAlexey Dobriyan static const struct file_operations fake_ide_media_proc_fops = { 2176613c5e8SAlexey Dobriyan .owner = THIS_MODULE, 2186613c5e8SAlexey Dobriyan .open = fake_ide_media_proc_open, 2196613c5e8SAlexey Dobriyan .read = seq_read, 2206613c5e8SAlexey Dobriyan .llseek = seq_lseek, 2216613c5e8SAlexey Dobriyan .release = single_release, 2226613c5e8SAlexey Dobriyan }; 2231da177e4SLinus Torvalds 224c0a9290eSWANG Cong static void make_ide_entries(const char *dev_name) 2251da177e4SLinus Torvalds { 2261da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2271da177e4SLinus Torvalds char name[64]; 2281da177e4SLinus Torvalds 2291da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2301da177e4SLinus Torvalds 2311da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2321da177e4SLinus Torvalds if(!dir) return; 2331da177e4SLinus Torvalds 2346613c5e8SAlexey Dobriyan ent = proc_create("media", S_IRUGO, dir, &fake_ide_media_proc_fops); 2351da177e4SLinus Torvalds if(!ent) return; 236c0a9290eSWANG Cong snprintf(name, sizeof(name), "ide0/%s", dev_name); 2371da177e4SLinus Torvalds proc_symlink(dev_name, proc_ide_root, name); 2381da177e4SLinus Torvalds } 2391da177e4SLinus Torvalds 2401da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2411da177e4SLinus Torvalds { 2421da177e4SLinus Torvalds fake_ide = 1; 243dc764e50SJeff Dike return 1; 2441da177e4SLinus Torvalds } 2451da177e4SLinus Torvalds 2461da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2471da177e4SLinus Torvalds 2481da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2491da177e4SLinus Torvalds "fake_ide\n" 2501da177e4SLinus Torvalds " Create ide0 entries that map onto ubd devices.\n\n" 2511da177e4SLinus Torvalds ); 2521da177e4SLinus Torvalds 2531da177e4SLinus Torvalds static int parse_unit(char **ptr) 2541da177e4SLinus Torvalds { 2551da177e4SLinus Torvalds char *str = *ptr, *end; 2561da177e4SLinus Torvalds int n = -1; 2571da177e4SLinus Torvalds 2581da177e4SLinus Torvalds if(isdigit(*str)) { 2591da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2601da177e4SLinus Torvalds if(end == str) 261dc764e50SJeff Dike return -1; 2621da177e4SLinus Torvalds *ptr = end; 2631da177e4SLinus Torvalds } 26497d88ac8SPaolo 'Blaisorblade' Giarrusso else if (('a' <= *str) && (*str <= 'z')) { 2651da177e4SLinus Torvalds n = *str - 'a'; 2661da177e4SLinus Torvalds str++; 2671da177e4SLinus Torvalds *ptr = str; 2681da177e4SLinus Torvalds } 269dc764e50SJeff Dike return n; 2701da177e4SLinus Torvalds } 2711da177e4SLinus Torvalds 272d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* If *index_out == -1 at exit, the passed option was a general one; 273d8d7c28eSPaolo 'Blaisorblade' Giarrusso * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it 274d8d7c28eSPaolo 'Blaisorblade' Giarrusso * should not be freed on exit. 275d8d7c28eSPaolo 'Blaisorblade' Giarrusso */ 276f28169d2SJeff Dike static int ubd_setup_common(char *str, int *index_out, char **error_out) 2771da177e4SLinus Torvalds { 2787d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 2791da177e4SLinus Torvalds struct openflags flags = global_openflags; 2801da177e4SLinus Torvalds char *backing_file; 281b8831a1dSJeff Dike int n, err = 0, i; 2821da177e4SLinus Torvalds 2831da177e4SLinus Torvalds if(index_out) *index_out = -1; 2841da177e4SLinus Torvalds n = *str; 2851da177e4SLinus Torvalds if(n == '='){ 2861da177e4SLinus Torvalds char *end; 2871da177e4SLinus Torvalds int major; 2881da177e4SLinus Torvalds 2891da177e4SLinus Torvalds str++; 2901da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 2911da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 292b8831a1dSJeff Dike goto out1; 2931da177e4SLinus Torvalds } 2941da177e4SLinus Torvalds 295f28169d2SJeff Dike err = -EINVAL; 296b8831a1dSJeff Dike major = simple_strtoul(str, &end, 0); 297b8831a1dSJeff Dike if((*end != '\0') || (end == str)){ 298b8831a1dSJeff Dike *error_out = "Didn't parse major number"; 299b8831a1dSJeff Dike goto out1; 300b8831a1dSJeff Dike } 301b8831a1dSJeff Dike 302d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 303792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 304f28169d2SJeff Dike *error_out = "Can't assign a fake major twice"; 3051da177e4SLinus Torvalds goto out1; 3061da177e4SLinus Torvalds } 3071da177e4SLinus Torvalds 3081da177e4SLinus Torvalds fake_major = major; 3091da177e4SLinus Torvalds 3101da177e4SLinus Torvalds printk(KERN_INFO "Setting extra ubd major number to %d\n", 3111da177e4SLinus Torvalds major); 3121da177e4SLinus Torvalds err = 0; 3131da177e4SLinus Torvalds out1: 314d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 315f28169d2SJeff Dike return err; 3161da177e4SLinus Torvalds } 3171da177e4SLinus Torvalds 3181da177e4SLinus Torvalds n = parse_unit(&str); 3191da177e4SLinus Torvalds if(n < 0){ 320f28169d2SJeff Dike *error_out = "Couldn't parse device number"; 321f28169d2SJeff Dike return -EINVAL; 3221da177e4SLinus Torvalds } 3231da177e4SLinus Torvalds if(n >= MAX_DEV){ 324f28169d2SJeff Dike *error_out = "Device number out of range"; 325f28169d2SJeff Dike return 1; 3261da177e4SLinus Torvalds } 3271da177e4SLinus Torvalds 328f28169d2SJeff Dike err = -EBUSY; 329d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 3301da177e4SLinus Torvalds 3317d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 3327d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file != NULL){ 333f28169d2SJeff Dike *error_out = "Device is already configured"; 3341da177e4SLinus Torvalds goto out; 3351da177e4SLinus Torvalds } 3361da177e4SLinus Torvalds 3371da177e4SLinus Torvalds if (index_out) 3381da177e4SLinus Torvalds *index_out = n; 3391da177e4SLinus Torvalds 340f28169d2SJeff Dike err = -EINVAL; 3416c29256cSJeff Dike for (i = 0; i < sizeof("rscd="); i++) { 3421da177e4SLinus Torvalds switch (*str) { 3431da177e4SLinus Torvalds case 'r': 3441da177e4SLinus Torvalds flags.w = 0; 3451da177e4SLinus Torvalds break; 3461da177e4SLinus Torvalds case 's': 3471da177e4SLinus Torvalds flags.s = 1; 3481da177e4SLinus Torvalds break; 3491da177e4SLinus Torvalds case 'd': 3507d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->no_cow = 1; 3511da177e4SLinus Torvalds break; 3526c29256cSJeff Dike case 'c': 3537d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->shared = 1; 3546c29256cSJeff Dike break; 3551da177e4SLinus Torvalds case '=': 3561da177e4SLinus Torvalds str++; 3571da177e4SLinus Torvalds goto break_loop; 3581da177e4SLinus Torvalds default: 359f28169d2SJeff Dike *error_out = "Expected '=' or flag letter " 360f28169d2SJeff Dike "(r, s, c, or d)"; 3611da177e4SLinus Torvalds goto out; 3621da177e4SLinus Torvalds } 3631da177e4SLinus Torvalds str++; 3641da177e4SLinus Torvalds } 3651da177e4SLinus Torvalds 3661da177e4SLinus Torvalds if (*str == '=') 367f28169d2SJeff Dike *error_out = "Too many flags specified"; 3681da177e4SLinus Torvalds else 369f28169d2SJeff Dike *error_out = "Missing '='"; 3701da177e4SLinus Torvalds goto out; 3711da177e4SLinus Torvalds 3721da177e4SLinus Torvalds break_loop: 3731da177e4SLinus Torvalds backing_file = strchr(str, ','); 3741da177e4SLinus Torvalds 375f28169d2SJeff Dike if (backing_file == NULL) 3761da177e4SLinus Torvalds backing_file = strchr(str, ':'); 3771da177e4SLinus Torvalds 378f28169d2SJeff Dike if(backing_file != NULL){ 379f28169d2SJeff Dike if(ubd_dev->no_cow){ 380f28169d2SJeff Dike *error_out = "Can't specify both 'd' and a cow file"; 381f28169d2SJeff Dike goto out; 382f28169d2SJeff Dike } 3831da177e4SLinus Torvalds else { 3841da177e4SLinus Torvalds *backing_file = '\0'; 3851da177e4SLinus Torvalds backing_file++; 3861da177e4SLinus Torvalds } 3871da177e4SLinus Torvalds } 388f28169d2SJeff Dike err = 0; 3897d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->file = str; 3907d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.file = backing_file; 3917d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->boot_openflags = flags; 3921da177e4SLinus Torvalds out: 393d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 394f28169d2SJeff Dike return err; 3951da177e4SLinus Torvalds } 3961da177e4SLinus Torvalds 3971da177e4SLinus Torvalds static int ubd_setup(char *str) 3981da177e4SLinus Torvalds { 399f28169d2SJeff Dike char *error; 400f28169d2SJeff Dike int err; 401f28169d2SJeff Dike 402f28169d2SJeff Dike err = ubd_setup_common(str, NULL, &error); 403f28169d2SJeff Dike if(err) 404f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize device with \"%s\" : " 405f28169d2SJeff Dike "%s\n", str, error); 406f28169d2SJeff Dike return 1; 4071da177e4SLinus Torvalds } 4081da177e4SLinus Torvalds 4091da177e4SLinus Torvalds __setup("ubd", ubd_setup); 4101da177e4SLinus Torvalds __uml_help(ubd_setup, 4111da177e4SLinus Torvalds "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" 4121da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 4131da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 4141da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 4151da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 4161da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 4171da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 418f28169d2SJeff Dike " When using only one filename, UML will detect whether to treat it like\n" 4191da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 4201da177e4SLinus Torvalds " flag:\n" 4211da177e4SLinus Torvalds " ubd0d=BackingFile\n" 4221da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 4231da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 4241da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 4251da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 4261da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 4271da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 4281da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 42920ede453SJeff Dike " an 's' will cause data to be written to disk on the host immediately.\n" 43020ede453SJeff Dike " 'c' will cause the device to be treated as being shared between multiple\n" 43120ede453SJeff Dike " UMLs and file locking will be turned off - this is appropriate for a\n" 43220ede453SJeff Dike " cluster filesystem and inappropriate at almost all other times.\n\n" 4331da177e4SLinus Torvalds ); 4341da177e4SLinus Torvalds 4358299ca5cSJeff Dike static int udb_setup(char *str) 4361da177e4SLinus Torvalds { 4371da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 4381da177e4SLinus Torvalds "udb TYPO\n", str); 439dc764e50SJeff Dike return 1; 4401da177e4SLinus Torvalds } 4411da177e4SLinus Torvalds 4421da177e4SLinus Torvalds __setup("udb", udb_setup); 4431da177e4SLinus Torvalds __uml_help(udb_setup, 4441da177e4SLinus Torvalds "udb\n" 4450894e27eSJeff Dike " This option is here solely to catch ubd -> udb typos, which can be\n" 4460894e27eSJeff Dike " to impossible to catch visually unless you specifically look for\n" 4470894e27eSJeff Dike " them. The only result of any option starting with 'udb' is an error\n" 4481da177e4SLinus Torvalds " in the boot output.\n\n" 4491da177e4SLinus Torvalds ); 4501da177e4SLinus Torvalds 451165125e1SJens Axboe static void do_ubd_request(struct request_queue * q); 45291acb21fSJeff Dike 45391acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 4545dc62b1bSWANG Cong static int thread_fd = -1; 455a0044bdfSJeff Dike static LIST_HEAD(restart); 45609ace81cSJeff Dike 457f88f0bdfSAnton Ivanov /* Function to read several request pointers at a time 458f88f0bdfSAnton Ivanov * handling fractional reads if (and as) needed 459f88f0bdfSAnton Ivanov */ 460f88f0bdfSAnton Ivanov 461f88f0bdfSAnton Ivanov static int bulk_req_safe_read( 462f88f0bdfSAnton Ivanov int fd, 463f88f0bdfSAnton Ivanov struct io_thread_req * (*request_buffer)[], 464f88f0bdfSAnton Ivanov struct io_thread_req **remainder, 465f88f0bdfSAnton Ivanov int *remainder_size, 466f88f0bdfSAnton Ivanov int max_recs 467f88f0bdfSAnton Ivanov ) 468f88f0bdfSAnton Ivanov { 469f88f0bdfSAnton Ivanov int n = 0; 470f88f0bdfSAnton Ivanov int res = 0; 471f88f0bdfSAnton Ivanov 472f88f0bdfSAnton Ivanov if (*remainder_size > 0) { 473f88f0bdfSAnton Ivanov memmove( 474f88f0bdfSAnton Ivanov (char *) request_buffer, 475f88f0bdfSAnton Ivanov (char *) remainder, *remainder_size 476f88f0bdfSAnton Ivanov ); 477f88f0bdfSAnton Ivanov n = *remainder_size; 478f88f0bdfSAnton Ivanov } 479f88f0bdfSAnton Ivanov 480f88f0bdfSAnton Ivanov res = os_read_file( 481f88f0bdfSAnton Ivanov fd, 482f88f0bdfSAnton Ivanov ((char *) request_buffer) + *remainder_size, 483f88f0bdfSAnton Ivanov sizeof(struct io_thread_req *)*max_recs 484f88f0bdfSAnton Ivanov - *remainder_size 485f88f0bdfSAnton Ivanov ); 486f88f0bdfSAnton Ivanov if (res > 0) { 487f88f0bdfSAnton Ivanov n += res; 488f88f0bdfSAnton Ivanov if ((n % sizeof(struct io_thread_req *)) > 0) { 489f88f0bdfSAnton Ivanov /* 490f88f0bdfSAnton Ivanov * Read somehow returned not a multiple of dword 491f88f0bdfSAnton Ivanov * theoretically possible, but never observed in the 492f88f0bdfSAnton Ivanov * wild, so read routine must be able to handle it 493f88f0bdfSAnton Ivanov */ 494f88f0bdfSAnton Ivanov *remainder_size = n % sizeof(struct io_thread_req *); 495f88f0bdfSAnton Ivanov WARN(*remainder_size > 0, "UBD IPC read returned a partial result"); 496f88f0bdfSAnton Ivanov memmove( 497f88f0bdfSAnton Ivanov remainder, 498f88f0bdfSAnton Ivanov ((char *) request_buffer) + 499f88f0bdfSAnton Ivanov (n/sizeof(struct io_thread_req *))*sizeof(struct io_thread_req *), 500f88f0bdfSAnton Ivanov *remainder_size 501f88f0bdfSAnton Ivanov ); 502f88f0bdfSAnton Ivanov n = n - *remainder_size; 503f88f0bdfSAnton Ivanov } 504f88f0bdfSAnton Ivanov } else { 505f88f0bdfSAnton Ivanov n = res; 506f88f0bdfSAnton Ivanov } 507f88f0bdfSAnton Ivanov return n; 508f88f0bdfSAnton Ivanov } 509f88f0bdfSAnton Ivanov 51062f96cb0SJeff Dike /* Called without dev->lock held, and only in interrupt context. */ 51191acb21fSJeff Dike static void ubd_handler(void) 51291acb21fSJeff Dike { 513a0044bdfSJeff Dike struct ubd *ubd; 514a0044bdfSJeff Dike struct list_head *list, *next_ele; 515a0044bdfSJeff Dike unsigned long flags; 51691acb21fSJeff Dike int n; 517f88f0bdfSAnton Ivanov int count; 51809ace81cSJeff Dike 519a0044bdfSJeff Dike while(1){ 520f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 521f88f0bdfSAnton Ivanov thread_fd, 522f88f0bdfSAnton Ivanov irq_req_buffer, 523f88f0bdfSAnton Ivanov &irq_remainder, 524f88f0bdfSAnton Ivanov &irq_remainder_size, 525f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 526f88f0bdfSAnton Ivanov ); 527f88f0bdfSAnton Ivanov if (n < 0) { 528a0044bdfSJeff Dike if(n == -EAGAIN) 529a0044bdfSJeff Dike break; 530a0044bdfSJeff Dike printk(KERN_ERR "spurious interrupt in ubd_handler, " 531a0044bdfSJeff Dike "err = %d\n", -n); 53291acb21fSJeff Dike return; 53391acb21fSJeff Dike } 534f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 535f88f0bdfSAnton Ivanov blk_end_request( 536f88f0bdfSAnton Ivanov (*irq_req_buffer)[count]->req, 537f88f0bdfSAnton Ivanov 0, 538f88f0bdfSAnton Ivanov (*irq_req_buffer)[count]->length 539f88f0bdfSAnton Ivanov ); 540f88f0bdfSAnton Ivanov kfree((*irq_req_buffer)[count]); 541f88f0bdfSAnton Ivanov } 542a0044bdfSJeff Dike } 54391acb21fSJeff Dike reactivate_fd(thread_fd, UBD_IRQ); 544a0044bdfSJeff Dike 545a0044bdfSJeff Dike list_for_each_safe(list, next_ele, &restart){ 546a0044bdfSJeff Dike ubd = container_of(list, struct ubd, restart); 547a0044bdfSJeff Dike list_del_init(&ubd->restart); 548a0044bdfSJeff Dike spin_lock_irqsave(&ubd->lock, flags); 549a0044bdfSJeff Dike do_ubd_request(ubd->queue); 550a0044bdfSJeff Dike spin_unlock_irqrestore(&ubd->lock, flags); 551a0044bdfSJeff Dike } 55291acb21fSJeff Dike } 55309ace81cSJeff Dike 5547bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 5551da177e4SLinus Torvalds { 55691acb21fSJeff Dike ubd_handler(); 557dc764e50SJeff Dike return IRQ_HANDLED; 5581da177e4SLinus Torvalds } 5591da177e4SLinus Torvalds 56091acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 56191acb21fSJeff Dike static int io_pid = -1; 56291acb21fSJeff Dike 5635dc62b1bSWANG Cong static void kill_io_thread(void) 56491acb21fSJeff Dike { 56591acb21fSJeff Dike if(io_pid != -1) 56691acb21fSJeff Dike os_kill_process(io_pid, 1); 56791acb21fSJeff Dike } 56891acb21fSJeff Dike 56991acb21fSJeff Dike __uml_exitcall(kill_io_thread); 57091acb21fSJeff Dike 571d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5721da177e4SLinus Torvalds { 5731da177e4SLinus Torvalds char *file; 57485356398SRichard Weinberger int fd; 57585356398SRichard Weinberger int err; 5761da177e4SLinus Torvalds 57785356398SRichard Weinberger __u32 version; 57885356398SRichard Weinberger __u32 align; 57985356398SRichard Weinberger char *backing_file; 58085356398SRichard Weinberger time_t mtime; 58185356398SRichard Weinberger unsigned long long size; 58285356398SRichard Weinberger int sector_size; 58385356398SRichard Weinberger int bitmap_offset; 58485356398SRichard Weinberger 58585356398SRichard Weinberger if (ubd_dev->file && ubd_dev->cow.file) { 58685356398SRichard Weinberger file = ubd_dev->cow.file; 58785356398SRichard Weinberger 58885356398SRichard Weinberger goto out; 58985356398SRichard Weinberger } 59085356398SRichard Weinberger 591d4afcba9SMartin Pärtel fd = os_open_file(ubd_dev->file, of_read(OPENFLAGS()), 0); 59285356398SRichard Weinberger if (fd < 0) 59385356398SRichard Weinberger return fd; 59485356398SRichard Weinberger 59585356398SRichard Weinberger err = read_cow_header(file_reader, &fd, &version, &backing_file, \ 59685356398SRichard Weinberger &mtime, &size, §or_size, &align, &bitmap_offset); 59785356398SRichard Weinberger os_close_file(fd); 59885356398SRichard Weinberger 59985356398SRichard Weinberger if(err == -EINVAL) 60085356398SRichard Weinberger file = ubd_dev->file; 60185356398SRichard Weinberger else 60285356398SRichard Weinberger file = backing_file; 60385356398SRichard Weinberger 60485356398SRichard Weinberger out: 605dc764e50SJeff Dike return os_file_size(file, size_out); 6061da177e4SLinus Torvalds } 6071da177e4SLinus Torvalds 6085dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 6095dc62b1bSWANG Cong { 6105dc62b1bSWANG Cong int err; 6115dc62b1bSWANG Cong 6128c6157b6SAnton Ivanov err = os_pread_file(fd, buf, len, offset); 6135dc62b1bSWANG Cong if (err < 0) 6145dc62b1bSWANG Cong return err; 6155dc62b1bSWANG Cong 6165dc62b1bSWANG Cong return 0; 6175dc62b1bSWANG Cong } 6185dc62b1bSWANG Cong 6195dc62b1bSWANG Cong static int backing_file_mismatch(char *file, __u64 size, time_t mtime) 6205dc62b1bSWANG Cong { 6215dc62b1bSWANG Cong unsigned long modtime; 6225dc62b1bSWANG Cong unsigned long long actual; 6235dc62b1bSWANG Cong int err; 6245dc62b1bSWANG Cong 6255dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 6265dc62b1bSWANG Cong if (err < 0) { 6275dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 6285dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 6295dc62b1bSWANG Cong return err; 6305dc62b1bSWANG Cong } 6315dc62b1bSWANG Cong 6325dc62b1bSWANG Cong err = os_file_size(file, &actual); 6335dc62b1bSWANG Cong if (err < 0) { 6345dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 6355dc62b1bSWANG Cong "err = %d\n", file, -err); 6365dc62b1bSWANG Cong return err; 6375dc62b1bSWANG Cong } 6385dc62b1bSWANG Cong 6395dc62b1bSWANG Cong if (actual != size) { 6405dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 6415dc62b1bSWANG Cong * the typecast.*/ 6425dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 6435dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 6445dc62b1bSWANG Cong return -EINVAL; 6455dc62b1bSWANG Cong } 6465dc62b1bSWANG Cong if (modtime != mtime) { 6475dc62b1bSWANG Cong printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " 6485dc62b1bSWANG Cong "backing file\n", mtime, modtime); 6495dc62b1bSWANG Cong return -EINVAL; 6505dc62b1bSWANG Cong } 6515dc62b1bSWANG Cong return 0; 6525dc62b1bSWANG Cong } 6535dc62b1bSWANG Cong 6545dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 6555dc62b1bSWANG Cong { 6565dc62b1bSWANG Cong struct uml_stat buf1, buf2; 6575dc62b1bSWANG Cong int err; 6585dc62b1bSWANG Cong 6595dc62b1bSWANG Cong if (from_cmdline == NULL) 6605dc62b1bSWANG Cong return 0; 6615dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 6625dc62b1bSWANG Cong return 0; 6635dc62b1bSWANG Cong 6645dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 6655dc62b1bSWANG Cong if (err < 0) { 6665dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 6675dc62b1bSWANG Cong -err); 6685dc62b1bSWANG Cong return 0; 6695dc62b1bSWANG Cong } 6705dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 6715dc62b1bSWANG Cong if (err < 0) { 6725dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 6735dc62b1bSWANG Cong -err); 6745dc62b1bSWANG Cong return 1; 6755dc62b1bSWANG Cong } 6765dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 6775dc62b1bSWANG Cong return 0; 6785dc62b1bSWANG Cong 6795dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 6805dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 6815dc62b1bSWANG Cong from_cmdline, from_cow, cow); 6825dc62b1bSWANG Cong return 1; 6835dc62b1bSWANG Cong } 6845dc62b1bSWANG Cong 6855dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 6865dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 6875dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6885dc62b1bSWANG Cong int *create_cow_out) 6895dc62b1bSWANG Cong { 6905dc62b1bSWANG Cong time_t mtime; 6915dc62b1bSWANG Cong unsigned long long size; 6925dc62b1bSWANG Cong __u32 version, align; 6935dc62b1bSWANG Cong char *backing_file; 6945dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6955dc62b1bSWANG Cong 6965dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6975dc62b1bSWANG Cong if (fd < 0) { 6985dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6995dc62b1bSWANG Cong *create_cow_out = 1; 7005dc62b1bSWANG Cong if (!openflags->w || 7015dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 7025dc62b1bSWANG Cong return fd; 7035dc62b1bSWANG Cong openflags->w = 0; 7045dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 7055dc62b1bSWANG Cong if (fd < 0) 7065dc62b1bSWANG Cong return fd; 7075dc62b1bSWANG Cong } 7085dc62b1bSWANG Cong 7095dc62b1bSWANG Cong if (shared) 7105dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 7115dc62b1bSWANG Cong else { 7125dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 7135dc62b1bSWANG Cong if (err < 0) { 7145dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 7155dc62b1bSWANG Cong file, -err); 7165dc62b1bSWANG Cong goto out_close; 7175dc62b1bSWANG Cong } 7185dc62b1bSWANG Cong } 7195dc62b1bSWANG Cong 7205dc62b1bSWANG Cong /* Successful return case! */ 7215dc62b1bSWANG Cong if (backing_file_out == NULL) 7225dc62b1bSWANG Cong return fd; 7235dc62b1bSWANG Cong 7245dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 7255dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 7265dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 7275dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 7285dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 7295dc62b1bSWANG Cong goto out_close; 7305dc62b1bSWANG Cong } 7315dc62b1bSWANG Cong if (err) 7325dc62b1bSWANG Cong return fd; 7335dc62b1bSWANG Cong 7345dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 7355dc62b1bSWANG Cong file); 7365dc62b1bSWANG Cong 7375dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 7385dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 7395dc62b1bSWANG Cong mtime)) { 7405dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 7415dc62b1bSWANG Cong *backing_file_out); 7425dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 7435dc62b1bSWANG Cong sectorsize, align, &size); 7445dc62b1bSWANG Cong if (err) { 7455dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 7465dc62b1bSWANG Cong goto out_close; 7475dc62b1bSWANG Cong } 7485dc62b1bSWANG Cong } else { 7495dc62b1bSWANG Cong *backing_file_out = backing_file; 7505dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 7515dc62b1bSWANG Cong if (err) 7525dc62b1bSWANG Cong goto out_close; 7535dc62b1bSWANG Cong } 7545dc62b1bSWANG Cong 7555dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 7565dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 7575dc62b1bSWANG Cong 7585dc62b1bSWANG Cong return fd; 7595dc62b1bSWANG Cong out_close: 7605dc62b1bSWANG Cong os_close_file(fd); 7615dc62b1bSWANG Cong return err; 7625dc62b1bSWANG Cong } 7635dc62b1bSWANG Cong 7645dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 7655dc62b1bSWANG Cong struct openflags flags, 7665dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 7675dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 7685dc62b1bSWANG Cong { 7695dc62b1bSWANG Cong int err, fd; 7705dc62b1bSWANG Cong 7715dc62b1bSWANG Cong flags.c = 1; 7725dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 7735dc62b1bSWANG Cong if (fd < 0) { 7745dc62b1bSWANG Cong err = fd; 7755dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 7765dc62b1bSWANG Cong cow_file, -err); 7775dc62b1bSWANG Cong goto out; 7785dc62b1bSWANG Cong } 7795dc62b1bSWANG Cong 7805dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 7815dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 7825dc62b1bSWANG Cong data_offset_out); 7835dc62b1bSWANG Cong if (!err) 7845dc62b1bSWANG Cong return fd; 7855dc62b1bSWANG Cong os_close_file(fd); 7865dc62b1bSWANG Cong out: 7875dc62b1bSWANG Cong return err; 7885dc62b1bSWANG Cong } 7895dc62b1bSWANG Cong 7905f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7911da177e4SLinus Torvalds { 7927d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7937d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7941da177e4SLinus Torvalds return; 7951da177e4SLinus Torvalds 7967d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7977d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7987d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7991da177e4SLinus Torvalds } 8001da177e4SLinus Torvalds 8017d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 8021da177e4SLinus Torvalds { 8031da177e4SLinus Torvalds struct openflags flags; 8041da177e4SLinus Torvalds char **back_ptr; 8051da177e4SLinus Torvalds int err, create_cow, *create_ptr; 8060bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 8071da177e4SLinus Torvalds 8087d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 8091da177e4SLinus Torvalds create_cow = 0; 8107d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 8117d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 8120bf16bffSPaolo 'Blaisorblade' Giarrusso 8130bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 8147d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 8157d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 8166c29256cSJeff Dike create_ptr); 8171da177e4SLinus Torvalds 8180bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 8190bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 8207d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags, 1 << 9, PAGE_SIZE, 8217d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 8227d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 8237d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 8240bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 8251da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 8267d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 8271da177e4SLinus Torvalds } 8281da177e4SLinus Torvalds } 8291da177e4SLinus Torvalds 8300bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 8317d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 8320bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 8330bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 8341da177e4SLinus Torvalds } 8350bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 8361da177e4SLinus Torvalds 8377d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 838086fa5ffSMartin K. Petersen blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); 839f4768ffdSJeff Dike 8401da177e4SLinus Torvalds err = -ENOMEM; 841da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 8427d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 8431da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 8441da177e4SLinus Torvalds goto error; 8451da177e4SLinus Torvalds } 8461da177e4SLinus Torvalds flush_tlb_kernel_vm(); 8471da177e4SLinus Torvalds 8487d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 8497d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 8507d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 8511da177e4SLinus Torvalds if(err < 0) 8521da177e4SLinus Torvalds goto error; 8531da177e4SLinus Torvalds 8547d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 8551da177e4SLinus Torvalds flags.w = 0; 8567d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 8576c29256cSJeff Dike NULL, NULL, NULL, NULL); 8581da177e4SLinus Torvalds if(err < 0) goto error; 8597d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 8601da177e4SLinus Torvalds } 861dc764e50SJeff Dike return 0; 8621da177e4SLinus Torvalds error: 8637d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 864dc764e50SJeff Dike return err; 8651da177e4SLinus Torvalds } 8661da177e4SLinus Torvalds 8672e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 8682e3f5251SJeff Dike { 8698691b97bSGreg Kroah-Hartman struct ubd *ubd_dev = dev_get_drvdata(dev); 8702e3f5251SJeff Dike 8712e3f5251SJeff Dike blk_cleanup_queue(ubd_dev->queue); 8722e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 8732e3f5251SJeff Dike } 8742e3f5251SJeff Dike 8755f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 8761da177e4SLinus Torvalds struct gendisk **disk_out) 8771da177e4SLinus Torvalds { 878d72a5783SDan Williams struct device *parent = NULL; 8791da177e4SLinus Torvalds struct gendisk *disk; 8801da177e4SLinus Torvalds 8811da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 8821da177e4SLinus Torvalds if(disk == NULL) 883dc764e50SJeff Dike return -ENOMEM; 8841da177e4SLinus Torvalds 8851da177e4SLinus Torvalds disk->major = major; 8861da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 8871da177e4SLinus Torvalds disk->fops = &ubd_blops; 8881da177e4SLinus Torvalds set_capacity(disk, size / 512); 889792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) 8901da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 891ce7b0f46SGreg Kroah-Hartman else 8921da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 8931da177e4SLinus Torvalds 8941da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 895792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) { 8967d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 8977d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 8982e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 8998691b97bSGreg Kroah-Hartman dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); 9007d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 901d72a5783SDan Williams parent = &ubd_devs[unit].pdev.dev; 9021da177e4SLinus Torvalds } 9031da177e4SLinus Torvalds 9047d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 90562f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 906d72a5783SDan Williams device_add_disk(parent, disk); 9071da177e4SLinus Torvalds 9081da177e4SLinus Torvalds *disk_out = disk; 9091da177e4SLinus Torvalds return 0; 9101da177e4SLinus Torvalds } 9111da177e4SLinus Torvalds 9121da177e4SLinus Torvalds #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) 9131da177e4SLinus Torvalds 914f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 9151da177e4SLinus Torvalds { 9167d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 917f28169d2SJeff Dike int err = 0; 9181da177e4SLinus Torvalds 9197d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 920ec7cf783SJeff Dike goto out; 9211da177e4SLinus Torvalds 9227d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 923f28169d2SJeff Dike if(err < 0){ 924f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 92580c13749SJeff Dike goto out; 926f28169d2SJeff Dike } 9271da177e4SLinus Torvalds 9287d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 9291da177e4SLinus Torvalds 930a0044bdfSJeff Dike INIT_LIST_HEAD(&ubd_dev->restart); 9314f40c055SWANG Cong sg_init_table(ubd_dev->sg, MAX_SG); 932a0044bdfSJeff Dike 93362f96cb0SJeff Dike err = -ENOMEM; 93462f96cb0SJeff Dike ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); 93562f96cb0SJeff Dike if (ubd_dev->queue == NULL) { 93662f96cb0SJeff Dike *error_out = "Failed to initialize device queue"; 93780c13749SJeff Dike goto out; 93862f96cb0SJeff Dike } 93962f96cb0SJeff Dike ubd_dev->queue->queuedata = ubd_dev; 940f935a8ceSJens Axboe blk_queue_write_cache(ubd_dev->queue, true, false); 94162f96cb0SJeff Dike 9428a78362cSMartin K. Petersen blk_queue_max_segments(ubd_dev->queue, MAX_SG); 943792dd4fcSChristoph Hellwig err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); 94462f96cb0SJeff Dike if(err){ 94562f96cb0SJeff Dike *error_out = "Failed to register device"; 94662f96cb0SJeff Dike goto out_cleanup; 94762f96cb0SJeff Dike } 9481da177e4SLinus Torvalds 949792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) 9505f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 9511da177e4SLinus Torvalds &fake_gendisk[n]); 9521da177e4SLinus Torvalds 95383380cc1SJeff Dike /* 95483380cc1SJeff Dike * Perhaps this should also be under the "if (fake_major)" above 95583380cc1SJeff Dike * using the fake_disk->disk_name 95683380cc1SJeff Dike */ 9571da177e4SLinus Torvalds if (fake_ide) 9581da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 9591da177e4SLinus Torvalds 960ec7cf783SJeff Dike err = 0; 961ec7cf783SJeff Dike out: 962ec7cf783SJeff Dike return err; 96362f96cb0SJeff Dike 96462f96cb0SJeff Dike out_cleanup: 96562f96cb0SJeff Dike blk_cleanup_queue(ubd_dev->queue); 96662f96cb0SJeff Dike goto out; 9671da177e4SLinus Torvalds } 9681da177e4SLinus Torvalds 969f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 9701da177e4SLinus Torvalds { 971e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 9721da177e4SLinus Torvalds 973f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 974f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 975f28169d2SJeff Dike * were set. 976f28169d2SJeff Dike */ 977970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 9781da177e4SLinus Torvalds if (str == NULL) { 979f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 980f28169d2SJeff Dike return -ENOMEM; 9811da177e4SLinus Torvalds } 982f28169d2SJeff Dike 983f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 984f28169d2SJeff Dike if (ret) 985e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 986f28169d2SJeff Dike 987e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 988e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 989d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 990e7f6552fSPaolo 'Blaisorblade' Giarrusso } 9911da177e4SLinus Torvalds 992d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 993f28169d2SJeff Dike ret = ubd_add(n, error_out); 994e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 9957d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 996d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 9971da177e4SLinus Torvalds 998e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 999e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 1000e7f6552fSPaolo 'Blaisorblade' Giarrusso 1001e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 1002e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 1003e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 10041da177e4SLinus Torvalds } 10051da177e4SLinus Torvalds 10061da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 10071da177e4SLinus Torvalds { 10087d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 10091da177e4SLinus Torvalds int n, len = 0; 10101da177e4SLinus Torvalds 10111da177e4SLinus Torvalds n = parse_unit(&name); 10121da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 10131da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 1014dc764e50SJeff Dike return -1; 10151da177e4SLinus Torvalds } 10161da177e4SLinus Torvalds 10177d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 1018d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10191da177e4SLinus Torvalds 10207d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 10211da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 10221da177e4SLinus Torvalds goto out; 10231da177e4SLinus Torvalds } 10241da177e4SLinus Torvalds 10257d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 10261da177e4SLinus Torvalds 10277d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 10281da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 10297d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 10301da177e4SLinus Torvalds } 10311da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 10321da177e4SLinus Torvalds 10331da177e4SLinus Torvalds out: 1034d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 1035dc764e50SJeff Dike return len; 10361da177e4SLinus Torvalds } 10371da177e4SLinus Torvalds 103829d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 103929d56cfeSJeff Dike { 104029d56cfeSJeff Dike int n; 104129d56cfeSJeff Dike 104229d56cfeSJeff Dike n = parse_unit(str); 104329d56cfeSJeff Dike *start_out = 0; 104429d56cfeSJeff Dike *end_out = MAX_DEV - 1; 104529d56cfeSJeff Dike return n; 104629d56cfeSJeff Dike } 104729d56cfeSJeff Dike 1048f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 10491da177e4SLinus Torvalds { 10502e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 10517d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 105229d56cfeSJeff Dike int err = -ENODEV; 10531da177e4SLinus Torvalds 1054d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10551da177e4SLinus Torvalds 10567d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 105729d56cfeSJeff Dike 10587d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 105929d56cfeSJeff Dike goto out; 106029d56cfeSJeff Dike 106129d56cfeSJeff Dike /* you cannot remove a open disk */ 106229d56cfeSJeff Dike err = -EBUSY; 10637d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 106429d56cfeSJeff Dike goto out; 106529d56cfeSJeff Dike 10661da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 1067b47d2debSJeff Dike if(disk != NULL){ 1068b47d2debSJeff Dike del_gendisk(disk); 1069b47d2debSJeff Dike put_disk(disk); 1070b47d2debSJeff Dike } 10711da177e4SLinus Torvalds 10721da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 10731da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 10741da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 10751da177e4SLinus Torvalds fake_gendisk[n] = NULL; 10761da177e4SLinus Torvalds } 10771da177e4SLinus Torvalds 10781da177e4SLinus Torvalds err = 0; 10792e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 10801da177e4SLinus Torvalds out: 1081d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 108229d56cfeSJeff Dike return err; 10831da177e4SLinus Torvalds } 10841da177e4SLinus Torvalds 1085f28169d2SJeff Dike /* All these are called by mconsole in process context and without 1086b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 1087f28169d2SJeff Dike */ 10881da177e4SLinus Torvalds static struct mc_device ubd_mc = { 108984f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 10901da177e4SLinus Torvalds .name = "ubd", 10911da177e4SLinus Torvalds .config = ubd_config, 10921da177e4SLinus Torvalds .get_config = ubd_get_config, 109329d56cfeSJeff Dike .id = ubd_id, 10941da177e4SLinus Torvalds .remove = ubd_remove, 10951da177e4SLinus Torvalds }; 10961da177e4SLinus Torvalds 1097d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 10981da177e4SLinus Torvalds { 10991da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 11001da177e4SLinus Torvalds return 0; 11011da177e4SLinus Torvalds } 11021da177e4SLinus Torvalds 11031da177e4SLinus Torvalds __initcall(ubd_mc_init); 11041da177e4SLinus Torvalds 1105d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1106d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1107d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1108d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1109b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1110d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1111d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1112b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1113b8831a1dSJeff Dike 1114dc764e50SJeff Dike return 0; 1115d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1116d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1117d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1118d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1119b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 11203ae5eaecSRussell King static struct platform_driver ubd_driver = { 11213ae5eaecSRussell King .driver = { 11221da177e4SLinus Torvalds .name = DRIVER_NAME, 11233ae5eaecSRussell King }, 11241da177e4SLinus Torvalds }; 11251da177e4SLinus Torvalds 1126d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 11271da177e4SLinus Torvalds { 1128f28169d2SJeff Dike char *error; 1129f28169d2SJeff Dike int i, err; 11301da177e4SLinus Torvalds 1131792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 11321da177e4SLinus Torvalds return -1; 11331da177e4SLinus Torvalds 1134792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 11351da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 11361da177e4SLinus Torvalds 11371da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 11381da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 11391da177e4SLinus Torvalds return -1; 11401da177e4SLinus Torvalds } 1141f88f0bdfSAnton Ivanov 1142f88f0bdfSAnton Ivanov irq_req_buffer = kmalloc( 1143f88f0bdfSAnton Ivanov sizeof(struct io_thread_req *) * UBD_REQ_BUFFER_SIZE, 1144f88f0bdfSAnton Ivanov GFP_KERNEL 1145f88f0bdfSAnton Ivanov ); 1146f88f0bdfSAnton Ivanov irq_remainder = 0; 1147f88f0bdfSAnton Ivanov 1148f88f0bdfSAnton Ivanov if (irq_req_buffer == NULL) { 1149f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1150f88f0bdfSAnton Ivanov return -1; 1151f88f0bdfSAnton Ivanov } 1152f88f0bdfSAnton Ivanov io_req_buffer = kmalloc( 1153f88f0bdfSAnton Ivanov sizeof(struct io_thread_req *) * UBD_REQ_BUFFER_SIZE, 1154f88f0bdfSAnton Ivanov GFP_KERNEL 1155f88f0bdfSAnton Ivanov ); 1156f88f0bdfSAnton Ivanov 1157f88f0bdfSAnton Ivanov io_remainder = 0; 1158f88f0bdfSAnton Ivanov 1159f88f0bdfSAnton Ivanov if (io_req_buffer == NULL) { 1160f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1161f88f0bdfSAnton Ivanov return -1; 1162f88f0bdfSAnton Ivanov } 11633ae5eaecSRussell King platform_driver_register(&ubd_driver); 1164b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1165f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1166f28169d2SJeff Dike err = ubd_add(i, &error); 1167f28169d2SJeff Dike if(err) 1168f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1169f28169d2SJeff Dike "%s\n", i, error); 1170f28169d2SJeff Dike } 1171b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 11721da177e4SLinus Torvalds return 0; 11731da177e4SLinus Torvalds } 11741da177e4SLinus Torvalds 11751da177e4SLinus Torvalds late_initcall(ubd_init); 11761da177e4SLinus Torvalds 1177d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 117891acb21fSJeff Dike unsigned long stack; 117991acb21fSJeff Dike int err; 118091acb21fSJeff Dike 118191acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 118291acb21fSJeff Dike if(global_openflags.s){ 118391acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 118491acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 118591acb21fSJeff Dike * enough. So use anyway the io thread. */ 118691acb21fSJeff Dike } 118791acb21fSJeff Dike stack = alloc_stack(0, 0); 118891acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 118991acb21fSJeff Dike &thread_fd); 119091acb21fSJeff Dike if(io_pid < 0){ 119191acb21fSJeff Dike printk(KERN_ERR 119291acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 119391acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 119491acb21fSJeff Dike io_pid = -1; 1195dc764e50SJeff Dike return 0; 119691acb21fSJeff Dike } 119791acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 1198c0b79a90SYong Zhang 0, "ubd", ubd_devs); 119991acb21fSJeff Dike if(err != 0) 120091acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1201f4c57a78SJeff Dike return 0; 120291acb21fSJeff Dike } 120391acb21fSJeff Dike 120491acb21fSJeff Dike device_initcall(ubd_driver_init); 120591acb21fSJeff Dike 1206a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 12071da177e4SLinus Torvalds { 1208a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 12097d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12101da177e4SLinus Torvalds int err = 0; 12111da177e4SLinus Torvalds 12129a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12137d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 12147d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 12151da177e4SLinus Torvalds if(err){ 12161da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 12177d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 12181da177e4SLinus Torvalds goto out; 12191da177e4SLinus Torvalds } 12201da177e4SLinus Torvalds } 12217d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 12227d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 12232c49be99SPaolo 'Blaisorblade' Giarrusso 12242c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 12252c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1226a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 12275f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 12281da177e4SLinus Torvalds err = -EROFS; 12292c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 12301da177e4SLinus Torvalds out: 12319a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 1232dc764e50SJeff Dike return err; 12331da177e4SLinus Torvalds } 12341da177e4SLinus Torvalds 1235db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode) 12361da177e4SLinus Torvalds { 12377d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12381da177e4SLinus Torvalds 12399a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12407d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 12415f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 12429a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 12431da177e4SLinus Torvalds } 12441da177e4SLinus Torvalds 124591acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 124691acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 124791acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 124891acb21fSJeff Dike __u64 bitmap_len) 12491da177e4SLinus Torvalds { 125091acb21fSJeff Dike __u64 sector = io_offset >> 9; 125191acb21fSJeff Dike int i, update_bitmap = 0; 12521da177e4SLinus Torvalds 125391acb21fSJeff Dike for(i = 0; i < length >> 9; i++){ 125491acb21fSJeff Dike if(cow_mask != NULL) 125591acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 125691acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 125709ace81cSJeff Dike continue; 12581da177e4SLinus Torvalds 125991acb21fSJeff Dike update_bitmap = 1; 126091acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 12611da177e4SLinus Torvalds } 126291acb21fSJeff Dike 126391acb21fSJeff Dike if(!update_bitmap) 126491acb21fSJeff Dike return; 126591acb21fSJeff Dike 126691acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 126791acb21fSJeff Dike 126891acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 126991acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 127091acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 127191acb21fSJeff Dike * for the original diagnosis. 127291acb21fSJeff Dike */ 12736d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 12746d074242SJiri Olsa sizeof(unsigned long)) - 1)) 127591acb21fSJeff Dike (*cow_offset)--; 127691acb21fSJeff Dike 127791acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 127891acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 127991acb21fSJeff Dike 128091acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 128191acb21fSJeff Dike *cow_offset += bitmap_offset; 128291acb21fSJeff Dike } 128391acb21fSJeff Dike 128491acb21fSJeff Dike static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, 128591acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 128691acb21fSJeff Dike { 128791acb21fSJeff Dike __u64 sector = req->offset >> 9; 128891acb21fSJeff Dike int i; 128991acb21fSJeff Dike 129091acb21fSJeff Dike if(req->length > (sizeof(req->sector_mask) * 8) << 9) 129191acb21fSJeff Dike panic("Operation too long"); 129291acb21fSJeff Dike 129391acb21fSJeff Dike if(req->op == UBD_READ) { 129491acb21fSJeff Dike for(i = 0; i < req->length >> 9; i++){ 129591acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 129691acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 129791acb21fSJeff Dike &req->sector_mask); 129891acb21fSJeff Dike } 129991acb21fSJeff Dike } 130091acb21fSJeff Dike else cowify_bitmap(req->offset, req->length, &req->sector_mask, 130191acb21fSJeff Dike &req->cow_offset, bitmap, bitmap_offset, 130291acb21fSJeff Dike req->bitmap_words, bitmap_len); 13031da177e4SLinus Torvalds } 13041da177e4SLinus Torvalds 130562f96cb0SJeff Dike /* Called with dev->lock held */ 1306a0044bdfSJeff Dike static void prepare_request(struct request *req, struct io_thread_req *io_req, 1307a0044bdfSJeff Dike unsigned long long offset, int page_offset, 1308a0044bdfSJeff Dike int len, struct page *page) 13091da177e4SLinus Torvalds { 13101da177e4SLinus Torvalds struct gendisk *disk = req->rq_disk; 13117d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 131291acb21fSJeff Dike 131362f96cb0SJeff Dike io_req->req = req; 1314a0044bdfSJeff Dike io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : 1315a0044bdfSJeff Dike ubd_dev->fd; 13167d314e34SPaolo 'Blaisorblade' Giarrusso io_req->fds[1] = ubd_dev->fd; 131791acb21fSJeff Dike io_req->cow_offset = -1; 13181da177e4SLinus Torvalds io_req->offset = offset; 13191da177e4SLinus Torvalds io_req->length = len; 13201da177e4SLinus Torvalds io_req->error = 0; 132191acb21fSJeff Dike io_req->sector_mask = 0; 132291acb21fSJeff Dike 132391acb21fSJeff Dike io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; 13241da177e4SLinus Torvalds io_req->offsets[0] = 0; 13257d314e34SPaolo 'Blaisorblade' Giarrusso io_req->offsets[1] = ubd_dev->cow.data_offset; 1326a0044bdfSJeff Dike io_req->buffer = page_address(page) + page_offset; 13271da177e4SLinus Torvalds io_req->sectorsize = 1 << 9; 13281da177e4SLinus Torvalds 13297d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL) 1330a0044bdfSJeff Dike cowify_req(io_req, ubd_dev->cow.bitmap, 1331a0044bdfSJeff Dike ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); 133291acb21fSJeff Dike 13331da177e4SLinus Torvalds } 13341da177e4SLinus Torvalds 133562f96cb0SJeff Dike /* Called with dev->lock held */ 1336805f11a0SRichard Weinberger static void prepare_flush_request(struct request *req, 1337805f11a0SRichard Weinberger struct io_thread_req *io_req) 1338805f11a0SRichard Weinberger { 1339805f11a0SRichard Weinberger struct gendisk *disk = req->rq_disk; 1340805f11a0SRichard Weinberger struct ubd *ubd_dev = disk->private_data; 1341805f11a0SRichard Weinberger 1342805f11a0SRichard Weinberger io_req->req = req; 1343805f11a0SRichard Weinberger io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : 1344805f11a0SRichard Weinberger ubd_dev->fd; 1345805f11a0SRichard Weinberger io_req->op = UBD_FLUSH; 1346805f11a0SRichard Weinberger } 1347805f11a0SRichard Weinberger 1348bc1d72e7SRichard Weinberger static bool submit_request(struct io_thread_req *io_req, struct ubd *dev) 1349bc1d72e7SRichard Weinberger { 1350bc1d72e7SRichard Weinberger int n = os_write_file(thread_fd, &io_req, 1351bc1d72e7SRichard Weinberger sizeof(io_req)); 1352bc1d72e7SRichard Weinberger if (n != sizeof(io_req)) { 1353bc1d72e7SRichard Weinberger if (n != -EAGAIN) 1354bc1d72e7SRichard Weinberger printk("write to io thread failed, " 1355bc1d72e7SRichard Weinberger "errno = %d\n", -n); 1356bc1d72e7SRichard Weinberger else if (list_empty(&dev->restart)) 1357bc1d72e7SRichard Weinberger list_add(&dev->restart, &restart); 1358bc1d72e7SRichard Weinberger 1359bc1d72e7SRichard Weinberger kfree(io_req); 1360bc1d72e7SRichard Weinberger return false; 1361bc1d72e7SRichard Weinberger } 1362bc1d72e7SRichard Weinberger return true; 1363bc1d72e7SRichard Weinberger } 1364bc1d72e7SRichard Weinberger 1365805f11a0SRichard Weinberger /* Called with dev->lock held */ 1366165125e1SJens Axboe static void do_ubd_request(struct request_queue *q) 13671da177e4SLinus Torvalds { 13682adcec21SJeff Dike struct io_thread_req *io_req; 13691da177e4SLinus Torvalds struct request *req; 13701da177e4SLinus Torvalds 1371a0044bdfSJeff Dike while(1){ 13722a9529a0SJeff Dike struct ubd *dev = q->queuedata; 13732a236122SThorsten Knabe if(dev->request == NULL){ 13749934c8c0STejun Heo struct request *req = blk_fetch_request(q); 1375a0044bdfSJeff Dike if(req == NULL) 137691acb21fSJeff Dike return; 1377a0044bdfSJeff Dike 1378a0044bdfSJeff Dike dev->request = req; 137947526903STejun Heo dev->rq_pos = blk_rq_pos(req); 1380a0044bdfSJeff Dike dev->start_sg = 0; 1381a0044bdfSJeff Dike dev->end_sg = blk_rq_map_sg(q, req, dev->sg); 1382a0044bdfSJeff Dike } 1383a0044bdfSJeff Dike 1384a0044bdfSJeff Dike req = dev->request; 1385805f11a0SRichard Weinberger 13863a5e02ceSMike Christie if (req_op(req) == REQ_OP_FLUSH) { 1387805f11a0SRichard Weinberger io_req = kmalloc(sizeof(struct io_thread_req), 1388805f11a0SRichard Weinberger GFP_ATOMIC); 1389805f11a0SRichard Weinberger if (io_req == NULL) { 1390805f11a0SRichard Weinberger if (list_empty(&dev->restart)) 1391805f11a0SRichard Weinberger list_add(&dev->restart, &restart); 1392805f11a0SRichard Weinberger return; 1393805f11a0SRichard Weinberger } 1394805f11a0SRichard Weinberger prepare_flush_request(req, io_req); 13952a236122SThorsten Knabe if (submit_request(io_req, dev) == false) 13962a236122SThorsten Knabe return; 1397805f11a0SRichard Weinberger } 1398805f11a0SRichard Weinberger 1399a0044bdfSJeff Dike while(dev->start_sg < dev->end_sg){ 1400a0044bdfSJeff Dike struct scatterlist *sg = &dev->sg[dev->start_sg]; 1401a0044bdfSJeff Dike 14022adcec21SJeff Dike io_req = kmalloc(sizeof(struct io_thread_req), 1403990c5587SPeter Zijlstra GFP_ATOMIC); 14042adcec21SJeff Dike if(io_req == NULL){ 14052adcec21SJeff Dike if(list_empty(&dev->restart)) 14062adcec21SJeff Dike list_add(&dev->restart, &restart); 14072adcec21SJeff Dike return; 14082adcec21SJeff Dike } 14092adcec21SJeff Dike prepare_request(req, io_req, 141047526903STejun Heo (unsigned long long)dev->rq_pos << 9, 141145711f1aSJens Axboe sg->offset, sg->length, sg_page(sg)); 1412a0044bdfSJeff Dike 1413bc1d72e7SRichard Weinberger if (submit_request(io_req, dev) == false) 1414a0044bdfSJeff Dike return; 1415a0044bdfSJeff Dike 141647526903STejun Heo dev->rq_pos += sg->length >> 9; 1417a0044bdfSJeff Dike dev->start_sg++; 1418a0044bdfSJeff Dike } 1419a0044bdfSJeff Dike dev->end_sg = 0; 1420a0044bdfSJeff Dike dev->request = NULL; 142191acb21fSJeff Dike } 14221da177e4SLinus Torvalds } 14231da177e4SLinus Torvalds 1424a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1425a885c8c4SChristoph Hellwig { 14267d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1427a885c8c4SChristoph Hellwig 1428a885c8c4SChristoph Hellwig geo->heads = 128; 1429a885c8c4SChristoph Hellwig geo->sectors = 32; 14307d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1431a885c8c4SChristoph Hellwig return 0; 1432a885c8c4SChristoph Hellwig } 1433a885c8c4SChristoph Hellwig 1434a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 14351da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 14361da177e4SLinus Torvalds { 1437a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 143873855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 14391da177e4SLinus Torvalds 14401da177e4SLinus Torvalds switch (cmd) { 14411da177e4SLinus Torvalds struct cdrom_volctrl volume; 14421da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 144373855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 144473855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 144573855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 144673855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 14471da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 14481da177e4SLinus Torvalds sizeof(ubd_id))) 1449dc764e50SJeff Dike return -EFAULT; 1450dc764e50SJeff Dike return 0; 14511da177e4SLinus Torvalds 14521da177e4SLinus Torvalds case CDROMVOLREAD: 14531da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1454dc764e50SJeff Dike return -EFAULT; 14551da177e4SLinus Torvalds volume.channel0 = 255; 14561da177e4SLinus Torvalds volume.channel1 = 255; 14571da177e4SLinus Torvalds volume.channel2 = 255; 14581da177e4SLinus Torvalds volume.channel3 = 255; 14591da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1460dc764e50SJeff Dike return -EFAULT; 1461dc764e50SJeff Dike return 0; 14621da177e4SLinus Torvalds } 1463dc764e50SJeff Dike return -EINVAL; 14641da177e4SLinus Torvalds } 14651da177e4SLinus Torvalds 146691acb21fSJeff Dike static int update_bitmap(struct io_thread_req *req) 14671da177e4SLinus Torvalds { 146891acb21fSJeff Dike int n; 146991acb21fSJeff Dike 147091acb21fSJeff Dike if(req->cow_offset == -1) 1471dc764e50SJeff Dike return 0; 147291acb21fSJeff Dike 14738c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[1], &req->bitmap_words, 14748c6157b6SAnton Ivanov sizeof(req->bitmap_words), req->cow_offset); 147591acb21fSJeff Dike if(n != sizeof(req->bitmap_words)){ 147691acb21fSJeff Dike printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, 147791acb21fSJeff Dike req->fds[1]); 1478dc764e50SJeff Dike return 1; 147991acb21fSJeff Dike } 148091acb21fSJeff Dike 1481dc764e50SJeff Dike return 0; 148291acb21fSJeff Dike } 148391acb21fSJeff Dike 14845dc62b1bSWANG Cong static void do_io(struct io_thread_req *req) 148591acb21fSJeff Dike { 14861da177e4SLinus Torvalds char *buf; 148791acb21fSJeff Dike unsigned long len; 148891acb21fSJeff Dike int n, nsectors, start, end, bit; 14891da177e4SLinus Torvalds __u64 off; 14901da177e4SLinus Torvalds 1491805f11a0SRichard Weinberger if (req->op == UBD_FLUSH) { 1492805f11a0SRichard Weinberger /* fds[0] is always either the rw image or our cow file */ 1493805f11a0SRichard Weinberger n = os_sync_file(req->fds[0]); 1494805f11a0SRichard Weinberger if (n != 0) { 1495805f11a0SRichard Weinberger printk("do_io - sync failed err = %d " 1496805f11a0SRichard Weinberger "fd = %d\n", -n, req->fds[0]); 1497805f11a0SRichard Weinberger req->error = 1; 1498805f11a0SRichard Weinberger } 1499805f11a0SRichard Weinberger return; 1500805f11a0SRichard Weinberger } 1501805f11a0SRichard Weinberger 15021da177e4SLinus Torvalds nsectors = req->length / req->sectorsize; 15031da177e4SLinus Torvalds start = 0; 15041da177e4SLinus Torvalds do { 150591acb21fSJeff Dike bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); 15061da177e4SLinus Torvalds end = start; 15071da177e4SLinus Torvalds while((end < nsectors) && 150891acb21fSJeff Dike (ubd_test_bit(end, (unsigned char *) 150991acb21fSJeff Dike &req->sector_mask) == bit)) 15101da177e4SLinus Torvalds end++; 15111da177e4SLinus Torvalds 151291acb21fSJeff Dike off = req->offset + req->offsets[bit] + 15131da177e4SLinus Torvalds start * req->sectorsize; 15141da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 15151da177e4SLinus Torvalds buf = &req->buffer[start * req->sectorsize]; 15161da177e4SLinus Torvalds 151791acb21fSJeff Dike if(req->op == UBD_READ){ 151891acb21fSJeff Dike n = 0; 151991acb21fSJeff Dike do { 152091acb21fSJeff Dike buf = &buf[n]; 152191acb21fSJeff Dike len -= n; 15228c6157b6SAnton Ivanov n = os_pread_file(req->fds[bit], buf, len, off); 152391acb21fSJeff Dike if (n < 0) { 152491acb21fSJeff Dike printk("do_io - read failed, err = %d " 152591acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 15261da177e4SLinus Torvalds req->error = 1; 15271da177e4SLinus Torvalds return; 15281da177e4SLinus Torvalds } 152991acb21fSJeff Dike } while((n < len) && (n != 0)); 153091acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 153191acb21fSJeff Dike } else { 15328c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[bit], buf, len, off); 153391acb21fSJeff Dike if(n != len){ 153491acb21fSJeff Dike printk("do_io - write failed err = %d " 153591acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 153691acb21fSJeff Dike req->error = 1; 153791acb21fSJeff Dike return; 153891acb21fSJeff Dike } 153991acb21fSJeff Dike } 15401da177e4SLinus Torvalds 15411da177e4SLinus Torvalds start = end; 15421da177e4SLinus Torvalds } while(start < nsectors); 154391acb21fSJeff Dike 154491acb21fSJeff Dike req->error = update_bitmap(req); 15451da177e4SLinus Torvalds } 154691acb21fSJeff Dike 154791acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 154891acb21fSJeff Dike * from ubd_init, which is an initcall. 154991acb21fSJeff Dike */ 155091acb21fSJeff Dike int kernel_fd = -1; 155191acb21fSJeff Dike 1552d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1553d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 155491acb21fSJeff Dike 155591acb21fSJeff Dike int io_thread(void *arg) 155691acb21fSJeff Dike { 1557f88f0bdfSAnton Ivanov int n, count, written, res; 155891acb21fSJeff Dike 155991d44ff8SRichard Weinberger os_fix_helper_signals(); 156091d44ff8SRichard Weinberger 156191acb21fSJeff Dike while(1){ 1562f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 1563f88f0bdfSAnton Ivanov kernel_fd, 1564f88f0bdfSAnton Ivanov io_req_buffer, 1565f88f0bdfSAnton Ivanov &io_remainder, 1566f88f0bdfSAnton Ivanov &io_remainder_size, 1567f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 1568f88f0bdfSAnton Ivanov ); 1569f88f0bdfSAnton Ivanov if (n < 0) { 1570f88f0bdfSAnton Ivanov if (n == -EAGAIN) { 1571f88f0bdfSAnton Ivanov ubd_read_poll(-1); 1572f88f0bdfSAnton Ivanov continue; 1573f88f0bdfSAnton Ivanov } else { 1574f88f0bdfSAnton Ivanov printk("io_thread - read failed, fd = %d, " 1575f88f0bdfSAnton Ivanov "err = %d," 1576f88f0bdfSAnton Ivanov "reminder = %d\n", 1577f88f0bdfSAnton Ivanov kernel_fd, -n, io_remainder_size); 1578f88f0bdfSAnton Ivanov } 1579f88f0bdfSAnton Ivanov } 1580f88f0bdfSAnton Ivanov 1581f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 1582f88f0bdfSAnton Ivanov io_count++; 1583f88f0bdfSAnton Ivanov do_io((*io_req_buffer)[count]); 1584f88f0bdfSAnton Ivanov } 1585f88f0bdfSAnton Ivanov 1586f88f0bdfSAnton Ivanov written = 0; 1587f88f0bdfSAnton Ivanov 1588f88f0bdfSAnton Ivanov do { 1589f88f0bdfSAnton Ivanov res = os_write_file(kernel_fd, ((char *) io_req_buffer) + written, n); 1590f88f0bdfSAnton Ivanov if (res > 0) { 1591f88f0bdfSAnton Ivanov written += res; 1592f88f0bdfSAnton Ivanov } else { 1593f88f0bdfSAnton Ivanov if (res != -EAGAIN) { 159491acb21fSJeff Dike printk("io_thread - read failed, fd = %d, " 159591acb21fSJeff Dike "err = %d\n", kernel_fd, -n); 159691acb21fSJeff Dike } 159791acb21fSJeff Dike } 1598f88f0bdfSAnton Ivanov if (written < n) { 1599f88f0bdfSAnton Ivanov ubd_write_poll(-1); 1600f88f0bdfSAnton Ivanov } 1601f88f0bdfSAnton Ivanov } while (written < n); 160291acb21fSJeff Dike } 160391acb21fSJeff Dike 16041b57e9c2SJeff Dike return 0; 16051b57e9c2SJeff Dike } 1606