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> 264e6da0feSRichard Weinberger #include <linux/blk-mq.h> 278ea3c06aSAl Viro #include <linux/ata.h> 288ea3c06aSAl Viro #include <linux/hdreg.h> 298ea3c06aSAl Viro #include <linux/cdrom.h> 308ea3c06aSAl Viro #include <linux/proc_fs.h> 318ea3c06aSAl Viro #include <linux/seq_file.h> 328ea3c06aSAl Viro #include <linux/ctype.h> 338ea3c06aSAl Viro #include <linux/slab.h> 348ea3c06aSAl Viro #include <linux/vmalloc.h> 358ea3c06aSAl Viro #include <linux/platform_device.h> 368ea3c06aSAl Viro #include <linux/scatterlist.h> 378ea3c06aSAl Viro #include <asm/tlbflush.h> 3837185b33SAl Viro #include <kern_util.h> 391da177e4SLinus Torvalds #include "mconsole_kern.h" 4037185b33SAl Viro #include <init.h> 4137185b33SAl Viro #include <irq_kern.h> 428ea3c06aSAl Viro #include "ubd.h" 4337185b33SAl Viro #include <os.h> 441da177e4SLinus Torvalds #include "cow.h" 451da177e4SLinus Torvalds 46805f11a0SRichard Weinberger enum ubd_req { UBD_READ, UBD_WRITE, UBD_FLUSH }; 471da177e4SLinus Torvalds 481da177e4SLinus Torvalds struct io_thread_req { 4962f96cb0SJeff Dike struct request *req; 5091acb21fSJeff Dike enum ubd_req op; 511da177e4SLinus Torvalds int fds[2]; 521da177e4SLinus Torvalds unsigned long offsets[2]; 531da177e4SLinus Torvalds unsigned long long offset; 541da177e4SLinus Torvalds unsigned long length; 551da177e4SLinus Torvalds char *buffer; 561da177e4SLinus Torvalds int sectorsize; 5791acb21fSJeff Dike unsigned long sector_mask; 5891acb21fSJeff Dike unsigned long long cow_offset; 5991acb21fSJeff Dike unsigned long bitmap_words[2]; 601da177e4SLinus Torvalds int error; 611da177e4SLinus Torvalds }; 621da177e4SLinus Torvalds 63f88f0bdfSAnton Ivanov 64f88f0bdfSAnton Ivanov static struct io_thread_req * (*irq_req_buffer)[]; 65f88f0bdfSAnton Ivanov static struct io_thread_req *irq_remainder; 66f88f0bdfSAnton Ivanov static int irq_remainder_size; 67f88f0bdfSAnton Ivanov 68f88f0bdfSAnton Ivanov static struct io_thread_req * (*io_req_buffer)[]; 69f88f0bdfSAnton Ivanov static struct io_thread_req *io_remainder; 70f88f0bdfSAnton Ivanov static int io_remainder_size; 71f88f0bdfSAnton Ivanov 72f88f0bdfSAnton Ivanov 73f88f0bdfSAnton Ivanov 7491acb21fSJeff Dike static inline int ubd_test_bit(__u64 bit, unsigned char *data) 751da177e4SLinus Torvalds { 761da177e4SLinus Torvalds __u64 n; 771da177e4SLinus Torvalds int bits, off; 781da177e4SLinus Torvalds 7991acb21fSJeff Dike bits = sizeof(data[0]) * 8; 801da177e4SLinus Torvalds n = bit / bits; 811da177e4SLinus Torvalds off = bit % bits; 82dc764e50SJeff Dike return (data[n] & (1 << off)) != 0; 831da177e4SLinus Torvalds } 841da177e4SLinus Torvalds 8591acb21fSJeff Dike static inline void ubd_set_bit(__u64 bit, unsigned char *data) 861da177e4SLinus Torvalds { 871da177e4SLinus Torvalds __u64 n; 881da177e4SLinus Torvalds int bits, off; 891da177e4SLinus Torvalds 9091acb21fSJeff Dike bits = sizeof(data[0]) * 8; 911da177e4SLinus Torvalds n = bit / bits; 921da177e4SLinus Torvalds off = bit % bits; 9391acb21fSJeff Dike data[n] |= (1 << off); 941da177e4SLinus Torvalds } 951da177e4SLinus Torvalds /*End stuff from ubd_user.h*/ 961da177e4SLinus Torvalds 971da177e4SLinus Torvalds #define DRIVER_NAME "uml-blkdev" 981da177e4SLinus Torvalds 99d7fb2c38SPaolo 'Blaisorblade' Giarrusso static DEFINE_MUTEX(ubd_lock); 1009a181c58SArnd Bergmann static DEFINE_MUTEX(ubd_mutex); /* replaces BKL, might not be needed */ 1011da177e4SLinus Torvalds 102a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode); 103db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode); 104a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 1051da177e4SLinus Torvalds unsigned int cmd, unsigned long arg); 106a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); 1071da177e4SLinus Torvalds 10897d88ac8SPaolo 'Blaisorblade' Giarrusso #define MAX_DEV (16) 1091da177e4SLinus Torvalds 11083d5cde4SAlexey Dobriyan static const struct block_device_operations ubd_blops = { 1111da177e4SLinus Torvalds .owner = THIS_MODULE, 112a625c998SAl Viro .open = ubd_open, 113a625c998SAl Viro .release = ubd_release, 114a625c998SAl Viro .ioctl = ubd_ioctl, 115a885c8c4SChristoph Hellwig .getgeo = ubd_getgeo, 1161da177e4SLinus Torvalds }; 1171da177e4SLinus Torvalds 1181da177e4SLinus Torvalds /* Protected by ubd_lock */ 119792dd4fcSChristoph Hellwig static int fake_major = UBD_MAJOR; 1201da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1211da177e4SLinus Torvalds static struct gendisk *fake_gendisk[MAX_DEV]; 1221da177e4SLinus Torvalds 1231da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1241da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1251da177e4SLinus Torvalds .cl = 1 }) 1261da177e4SLinus Torvalds #else 1271da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1281da177e4SLinus Torvalds .cl = 1 }) 1291da177e4SLinus Torvalds #endif 1301da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1311da177e4SLinus Torvalds 1321da177e4SLinus Torvalds struct cow { 1332a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file name */ 1341da177e4SLinus Torvalds char *file; 1352a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file fd */ 1361da177e4SLinus Torvalds int fd; 1371da177e4SLinus Torvalds unsigned long *bitmap; 1381da177e4SLinus Torvalds unsigned long bitmap_len; 1391da177e4SLinus Torvalds int bitmap_offset; 1401da177e4SLinus Torvalds int data_offset; 1411da177e4SLinus Torvalds }; 1421da177e4SLinus Torvalds 143a0044bdfSJeff Dike #define MAX_SG 64 144a0044bdfSJeff Dike 1451da177e4SLinus Torvalds struct ubd { 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; 1594e6da0feSRichard Weinberger struct blk_mq_tag_set tag_set; 16062f96cb0SJeff Dike spinlock_t lock; 1614e6da0feSRichard Weinberger }; 1624e6da0feSRichard Weinberger 1631da177e4SLinus Torvalds #define DEFAULT_COW { \ 1641da177e4SLinus Torvalds .file = NULL, \ 1651da177e4SLinus Torvalds .fd = -1, \ 1661da177e4SLinus Torvalds .bitmap = NULL, \ 1671da177e4SLinus Torvalds .bitmap_offset = 0, \ 1681da177e4SLinus Torvalds .data_offset = 0, \ 1691da177e4SLinus Torvalds } 1701da177e4SLinus Torvalds 1711da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1721da177e4SLinus Torvalds .file = NULL, \ 1731da177e4SLinus Torvalds .count = 0, \ 1741da177e4SLinus Torvalds .fd = -1, \ 1751da177e4SLinus Torvalds .size = -1, \ 1761da177e4SLinus Torvalds .boot_openflags = OPEN_FLAGS, \ 1771da177e4SLinus Torvalds .openflags = OPEN_FLAGS, \ 1781da177e4SLinus Torvalds .no_cow = 0, \ 1796c29256cSJeff Dike .shared = 0, \ 1801da177e4SLinus Torvalds .cow = DEFAULT_COW, \ 18122e65004SThomas Gleixner .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \ 1821da177e4SLinus Torvalds } 1831da177e4SLinus Torvalds 184b8831a1dSJeff Dike /* Protected by ubd_lock */ 1855dc62b1bSWANG Cong static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; 1861da177e4SLinus Torvalds 1871da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 1881da177e4SLinus Torvalds static int fake_ide = 0; 1891da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 1901da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 1911da177e4SLinus Torvalds 1924e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 1934e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd); 1944e6da0feSRichard Weinberger 1951da177e4SLinus Torvalds static void make_proc_ide(void) 1961da177e4SLinus Torvalds { 1971da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 1981da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 1991da177e4SLinus Torvalds } 2001da177e4SLinus Torvalds 2016613c5e8SAlexey Dobriyan static int fake_ide_media_proc_show(struct seq_file *m, void *v) 2021da177e4SLinus Torvalds { 2036613c5e8SAlexey Dobriyan seq_puts(m, "disk\n"); 2046613c5e8SAlexey Dobriyan return 0; 2056613c5e8SAlexey Dobriyan } 2061da177e4SLinus Torvalds 207c0a9290eSWANG Cong static void make_ide_entries(const char *dev_name) 2081da177e4SLinus Torvalds { 2091da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2101da177e4SLinus Torvalds char name[64]; 2111da177e4SLinus Torvalds 2121da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2131da177e4SLinus Torvalds 2141da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2151da177e4SLinus Torvalds if(!dir) return; 2161da177e4SLinus Torvalds 2173f3942acSChristoph Hellwig ent = proc_create_single("media", S_IRUGO, dir, 2183f3942acSChristoph Hellwig fake_ide_media_proc_show); 2191da177e4SLinus Torvalds if(!ent) return; 220c0a9290eSWANG Cong snprintf(name, sizeof(name), "ide0/%s", dev_name); 2211da177e4SLinus Torvalds proc_symlink(dev_name, proc_ide_root, name); 2221da177e4SLinus Torvalds } 2231da177e4SLinus Torvalds 2241da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2251da177e4SLinus Torvalds { 2261da177e4SLinus Torvalds fake_ide = 1; 227dc764e50SJeff Dike return 1; 2281da177e4SLinus Torvalds } 2291da177e4SLinus Torvalds 2301da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2311da177e4SLinus Torvalds 2321da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2331da177e4SLinus Torvalds "fake_ide\n" 2341da177e4SLinus Torvalds " Create ide0 entries that map onto ubd devices.\n\n" 2351da177e4SLinus Torvalds ); 2361da177e4SLinus Torvalds 2371da177e4SLinus Torvalds static int parse_unit(char **ptr) 2381da177e4SLinus Torvalds { 2391da177e4SLinus Torvalds char *str = *ptr, *end; 2401da177e4SLinus Torvalds int n = -1; 2411da177e4SLinus Torvalds 2421da177e4SLinus Torvalds if(isdigit(*str)) { 2431da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2441da177e4SLinus Torvalds if(end == str) 245dc764e50SJeff Dike return -1; 2461da177e4SLinus Torvalds *ptr = end; 2471da177e4SLinus Torvalds } 24897d88ac8SPaolo 'Blaisorblade' Giarrusso else if (('a' <= *str) && (*str <= 'z')) { 2491da177e4SLinus Torvalds n = *str - 'a'; 2501da177e4SLinus Torvalds str++; 2511da177e4SLinus Torvalds *ptr = str; 2521da177e4SLinus Torvalds } 253dc764e50SJeff Dike return n; 2541da177e4SLinus Torvalds } 2551da177e4SLinus Torvalds 256d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* If *index_out == -1 at exit, the passed option was a general one; 257d8d7c28eSPaolo 'Blaisorblade' Giarrusso * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it 258d8d7c28eSPaolo 'Blaisorblade' Giarrusso * should not be freed on exit. 259d8d7c28eSPaolo 'Blaisorblade' Giarrusso */ 260f28169d2SJeff Dike static int ubd_setup_common(char *str, int *index_out, char **error_out) 2611da177e4SLinus Torvalds { 2627d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 2631da177e4SLinus Torvalds struct openflags flags = global_openflags; 2641da177e4SLinus Torvalds char *backing_file; 265b8831a1dSJeff Dike int n, err = 0, i; 2661da177e4SLinus Torvalds 2671da177e4SLinus Torvalds if(index_out) *index_out = -1; 2681da177e4SLinus Torvalds n = *str; 2691da177e4SLinus Torvalds if(n == '='){ 2701da177e4SLinus Torvalds char *end; 2711da177e4SLinus Torvalds int major; 2721da177e4SLinus Torvalds 2731da177e4SLinus Torvalds str++; 2741da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 2751da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 276b8831a1dSJeff Dike goto out1; 2771da177e4SLinus Torvalds } 2781da177e4SLinus Torvalds 279f28169d2SJeff Dike err = -EINVAL; 280b8831a1dSJeff Dike major = simple_strtoul(str, &end, 0); 281b8831a1dSJeff Dike if((*end != '\0') || (end == str)){ 282b8831a1dSJeff Dike *error_out = "Didn't parse major number"; 283b8831a1dSJeff Dike goto out1; 284b8831a1dSJeff Dike } 285b8831a1dSJeff Dike 286d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 287792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 288f28169d2SJeff Dike *error_out = "Can't assign a fake major twice"; 2891da177e4SLinus Torvalds goto out1; 2901da177e4SLinus Torvalds } 2911da177e4SLinus Torvalds 2921da177e4SLinus Torvalds fake_major = major; 2931da177e4SLinus Torvalds 2941da177e4SLinus Torvalds printk(KERN_INFO "Setting extra ubd major number to %d\n", 2951da177e4SLinus Torvalds major); 2961da177e4SLinus Torvalds err = 0; 2971da177e4SLinus Torvalds out1: 298d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 299f28169d2SJeff Dike return err; 3001da177e4SLinus Torvalds } 3011da177e4SLinus Torvalds 3021da177e4SLinus Torvalds n = parse_unit(&str); 3031da177e4SLinus Torvalds if(n < 0){ 304f28169d2SJeff Dike *error_out = "Couldn't parse device number"; 305f28169d2SJeff Dike return -EINVAL; 3061da177e4SLinus Torvalds } 3071da177e4SLinus Torvalds if(n >= MAX_DEV){ 308f28169d2SJeff Dike *error_out = "Device number out of range"; 309f28169d2SJeff Dike return 1; 3101da177e4SLinus Torvalds } 3111da177e4SLinus Torvalds 312f28169d2SJeff Dike err = -EBUSY; 313d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 3141da177e4SLinus Torvalds 3157d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 3167d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file != NULL){ 317f28169d2SJeff Dike *error_out = "Device is already configured"; 3181da177e4SLinus Torvalds goto out; 3191da177e4SLinus Torvalds } 3201da177e4SLinus Torvalds 3211da177e4SLinus Torvalds if (index_out) 3221da177e4SLinus Torvalds *index_out = n; 3231da177e4SLinus Torvalds 324f28169d2SJeff Dike err = -EINVAL; 3256c29256cSJeff Dike for (i = 0; i < sizeof("rscd="); i++) { 3261da177e4SLinus Torvalds switch (*str) { 3271da177e4SLinus Torvalds case 'r': 3281da177e4SLinus Torvalds flags.w = 0; 3291da177e4SLinus Torvalds break; 3301da177e4SLinus Torvalds case 's': 3311da177e4SLinus Torvalds flags.s = 1; 3321da177e4SLinus Torvalds break; 3331da177e4SLinus Torvalds case 'd': 3347d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->no_cow = 1; 3351da177e4SLinus Torvalds break; 3366c29256cSJeff Dike case 'c': 3377d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->shared = 1; 3386c29256cSJeff Dike break; 3391da177e4SLinus Torvalds case '=': 3401da177e4SLinus Torvalds str++; 3411da177e4SLinus Torvalds goto break_loop; 3421da177e4SLinus Torvalds default: 343f28169d2SJeff Dike *error_out = "Expected '=' or flag letter " 344f28169d2SJeff Dike "(r, s, c, or d)"; 3451da177e4SLinus Torvalds goto out; 3461da177e4SLinus Torvalds } 3471da177e4SLinus Torvalds str++; 3481da177e4SLinus Torvalds } 3491da177e4SLinus Torvalds 3501da177e4SLinus Torvalds if (*str == '=') 351f28169d2SJeff Dike *error_out = "Too many flags specified"; 3521da177e4SLinus Torvalds else 353f28169d2SJeff Dike *error_out = "Missing '='"; 3541da177e4SLinus Torvalds goto out; 3551da177e4SLinus Torvalds 3561da177e4SLinus Torvalds break_loop: 3571da177e4SLinus Torvalds backing_file = strchr(str, ','); 3581da177e4SLinus Torvalds 359f28169d2SJeff Dike if (backing_file == NULL) 3601da177e4SLinus Torvalds backing_file = strchr(str, ':'); 3611da177e4SLinus Torvalds 362f28169d2SJeff Dike if(backing_file != NULL){ 363f28169d2SJeff Dike if(ubd_dev->no_cow){ 364f28169d2SJeff Dike *error_out = "Can't specify both 'd' and a cow file"; 365f28169d2SJeff Dike goto out; 366f28169d2SJeff Dike } 3671da177e4SLinus Torvalds else { 3681da177e4SLinus Torvalds *backing_file = '\0'; 3691da177e4SLinus Torvalds backing_file++; 3701da177e4SLinus Torvalds } 3711da177e4SLinus Torvalds } 372f28169d2SJeff Dike err = 0; 3737d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->file = str; 3747d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.file = backing_file; 3757d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->boot_openflags = flags; 3761da177e4SLinus Torvalds out: 377d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 378f28169d2SJeff Dike return err; 3791da177e4SLinus Torvalds } 3801da177e4SLinus Torvalds 3811da177e4SLinus Torvalds static int ubd_setup(char *str) 3821da177e4SLinus Torvalds { 383f28169d2SJeff Dike char *error; 384f28169d2SJeff Dike int err; 385f28169d2SJeff Dike 386f28169d2SJeff Dike err = ubd_setup_common(str, NULL, &error); 387f28169d2SJeff Dike if(err) 388f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize device with \"%s\" : " 389f28169d2SJeff Dike "%s\n", str, error); 390f28169d2SJeff Dike return 1; 3911da177e4SLinus Torvalds } 3921da177e4SLinus Torvalds 3931da177e4SLinus Torvalds __setup("ubd", ubd_setup); 3941da177e4SLinus Torvalds __uml_help(ubd_setup, 3951da177e4SLinus Torvalds "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" 3961da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 3971da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 3981da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 3991da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 4001da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 4011da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 402f28169d2SJeff Dike " When using only one filename, UML will detect whether to treat it like\n" 4031da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 4041da177e4SLinus Torvalds " flag:\n" 4051da177e4SLinus Torvalds " ubd0d=BackingFile\n" 4061da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 4071da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 4081da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 4091da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 4101da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 4111da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 4121da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 41320ede453SJeff Dike " an 's' will cause data to be written to disk on the host immediately.\n" 41420ede453SJeff Dike " 'c' will cause the device to be treated as being shared between multiple\n" 41520ede453SJeff Dike " UMLs and file locking will be turned off - this is appropriate for a\n" 41620ede453SJeff Dike " cluster filesystem and inappropriate at almost all other times.\n\n" 4171da177e4SLinus Torvalds ); 4181da177e4SLinus Torvalds 4198299ca5cSJeff Dike static int udb_setup(char *str) 4201da177e4SLinus Torvalds { 4211da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 4221da177e4SLinus Torvalds "udb TYPO\n", str); 423dc764e50SJeff Dike return 1; 4241da177e4SLinus Torvalds } 4251da177e4SLinus Torvalds 4261da177e4SLinus Torvalds __setup("udb", udb_setup); 4271da177e4SLinus Torvalds __uml_help(udb_setup, 4281da177e4SLinus Torvalds "udb\n" 4290894e27eSJeff Dike " This option is here solely to catch ubd -> udb typos, which can be\n" 4300894e27eSJeff Dike " to impossible to catch visually unless you specifically look for\n" 4310894e27eSJeff Dike " them. The only result of any option starting with 'udb' is an error\n" 4321da177e4SLinus Torvalds " in the boot output.\n\n" 4331da177e4SLinus Torvalds ); 4341da177e4SLinus Torvalds 43591acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 4365dc62b1bSWANG Cong static int thread_fd = -1; 43709ace81cSJeff Dike 438f88f0bdfSAnton Ivanov /* Function to read several request pointers at a time 439f88f0bdfSAnton Ivanov * handling fractional reads if (and as) needed 440f88f0bdfSAnton Ivanov */ 441f88f0bdfSAnton Ivanov 442f88f0bdfSAnton Ivanov static int bulk_req_safe_read( 443f88f0bdfSAnton Ivanov int fd, 444f88f0bdfSAnton Ivanov struct io_thread_req * (*request_buffer)[], 445f88f0bdfSAnton Ivanov struct io_thread_req **remainder, 446f88f0bdfSAnton Ivanov int *remainder_size, 447f88f0bdfSAnton Ivanov int max_recs 448f88f0bdfSAnton Ivanov ) 449f88f0bdfSAnton Ivanov { 450f88f0bdfSAnton Ivanov int n = 0; 451f88f0bdfSAnton Ivanov int res = 0; 452f88f0bdfSAnton Ivanov 453f88f0bdfSAnton Ivanov if (*remainder_size > 0) { 454f88f0bdfSAnton Ivanov memmove( 455f88f0bdfSAnton Ivanov (char *) request_buffer, 456f88f0bdfSAnton Ivanov (char *) remainder, *remainder_size 457f88f0bdfSAnton Ivanov ); 458f88f0bdfSAnton Ivanov n = *remainder_size; 459f88f0bdfSAnton Ivanov } 460f88f0bdfSAnton Ivanov 461f88f0bdfSAnton Ivanov res = os_read_file( 462f88f0bdfSAnton Ivanov fd, 463f88f0bdfSAnton Ivanov ((char *) request_buffer) + *remainder_size, 464f88f0bdfSAnton Ivanov sizeof(struct io_thread_req *)*max_recs 465f88f0bdfSAnton Ivanov - *remainder_size 466f88f0bdfSAnton Ivanov ); 467f88f0bdfSAnton Ivanov if (res > 0) { 468f88f0bdfSAnton Ivanov n += res; 469f88f0bdfSAnton Ivanov if ((n % sizeof(struct io_thread_req *)) > 0) { 470f88f0bdfSAnton Ivanov /* 471f88f0bdfSAnton Ivanov * Read somehow returned not a multiple of dword 472f88f0bdfSAnton Ivanov * theoretically possible, but never observed in the 473f88f0bdfSAnton Ivanov * wild, so read routine must be able to handle it 474f88f0bdfSAnton Ivanov */ 475f88f0bdfSAnton Ivanov *remainder_size = n % sizeof(struct io_thread_req *); 476f88f0bdfSAnton Ivanov WARN(*remainder_size > 0, "UBD IPC read returned a partial result"); 477f88f0bdfSAnton Ivanov memmove( 478f88f0bdfSAnton Ivanov remainder, 479f88f0bdfSAnton Ivanov ((char *) request_buffer) + 480f88f0bdfSAnton Ivanov (n/sizeof(struct io_thread_req *))*sizeof(struct io_thread_req *), 481f88f0bdfSAnton Ivanov *remainder_size 482f88f0bdfSAnton Ivanov ); 483f88f0bdfSAnton Ivanov n = n - *remainder_size; 484f88f0bdfSAnton Ivanov } 485f88f0bdfSAnton Ivanov } else { 486f88f0bdfSAnton Ivanov n = res; 487f88f0bdfSAnton Ivanov } 488f88f0bdfSAnton Ivanov return n; 489f88f0bdfSAnton Ivanov } 490f88f0bdfSAnton Ivanov 49162f96cb0SJeff Dike /* Called without dev->lock held, and only in interrupt context. */ 49291acb21fSJeff Dike static void ubd_handler(void) 49391acb21fSJeff Dike { 49491acb21fSJeff Dike int n; 495f88f0bdfSAnton Ivanov int count; 49609ace81cSJeff Dike 497a0044bdfSJeff Dike while(1){ 498f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 499f88f0bdfSAnton Ivanov thread_fd, 500f88f0bdfSAnton Ivanov irq_req_buffer, 501f88f0bdfSAnton Ivanov &irq_remainder, 502f88f0bdfSAnton Ivanov &irq_remainder_size, 503f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 504f88f0bdfSAnton Ivanov ); 505f88f0bdfSAnton Ivanov if (n < 0) { 506a0044bdfSJeff Dike if(n == -EAGAIN) 507a0044bdfSJeff Dike break; 508a0044bdfSJeff Dike printk(KERN_ERR "spurious interrupt in ubd_handler, " 509a0044bdfSJeff Dike "err = %d\n", -n); 51091acb21fSJeff Dike return; 51191acb21fSJeff Dike } 512f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 5134e6da0feSRichard Weinberger struct io_thread_req *io_req = (*irq_req_buffer)[count]; 5144e6da0feSRichard Weinberger int err = io_req->error ? BLK_STS_IOERR : BLK_STS_OK; 515a0044bdfSJeff Dike 5164e6da0feSRichard Weinberger if (!blk_update_request(io_req->req, err, io_req->length)) 5174e6da0feSRichard Weinberger __blk_mq_end_request(io_req->req, err); 5184e6da0feSRichard Weinberger 5194e6da0feSRichard Weinberger kfree(io_req); 520a0044bdfSJeff Dike } 52191acb21fSJeff Dike } 52209ace81cSJeff Dike 5234e6da0feSRichard Weinberger reactivate_fd(thread_fd, UBD_IRQ); 5244e6da0feSRichard Weinberger } 5254e6da0feSRichard Weinberger 5267bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 5271da177e4SLinus Torvalds { 52891acb21fSJeff Dike ubd_handler(); 529dc764e50SJeff Dike return IRQ_HANDLED; 5301da177e4SLinus Torvalds } 5311da177e4SLinus Torvalds 53291acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 53391acb21fSJeff Dike static int io_pid = -1; 53491acb21fSJeff Dike 5355dc62b1bSWANG Cong static void kill_io_thread(void) 53691acb21fSJeff Dike { 53791acb21fSJeff Dike if(io_pid != -1) 53891acb21fSJeff Dike os_kill_process(io_pid, 1); 53991acb21fSJeff Dike } 54091acb21fSJeff Dike 54191acb21fSJeff Dike __uml_exitcall(kill_io_thread); 54291acb21fSJeff Dike 543d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5441da177e4SLinus Torvalds { 5451da177e4SLinus Torvalds char *file; 54685356398SRichard Weinberger int fd; 54785356398SRichard Weinberger int err; 5481da177e4SLinus Torvalds 54985356398SRichard Weinberger __u32 version; 55085356398SRichard Weinberger __u32 align; 55185356398SRichard Weinberger char *backing_file; 55285356398SRichard Weinberger time_t mtime; 55385356398SRichard Weinberger unsigned long long size; 55485356398SRichard Weinberger int sector_size; 55585356398SRichard Weinberger int bitmap_offset; 55685356398SRichard Weinberger 55785356398SRichard Weinberger if (ubd_dev->file && ubd_dev->cow.file) { 55885356398SRichard Weinberger file = ubd_dev->cow.file; 55985356398SRichard Weinberger 56085356398SRichard Weinberger goto out; 56185356398SRichard Weinberger } 56285356398SRichard Weinberger 563d4afcba9SMartin Pärtel fd = os_open_file(ubd_dev->file, of_read(OPENFLAGS()), 0); 56485356398SRichard Weinberger if (fd < 0) 56585356398SRichard Weinberger return fd; 56685356398SRichard Weinberger 56785356398SRichard Weinberger err = read_cow_header(file_reader, &fd, &version, &backing_file, \ 56885356398SRichard Weinberger &mtime, &size, §or_size, &align, &bitmap_offset); 56985356398SRichard Weinberger os_close_file(fd); 57085356398SRichard Weinberger 57185356398SRichard Weinberger if(err == -EINVAL) 57285356398SRichard Weinberger file = ubd_dev->file; 57385356398SRichard Weinberger else 57485356398SRichard Weinberger file = backing_file; 57585356398SRichard Weinberger 57685356398SRichard Weinberger out: 577dc764e50SJeff Dike return os_file_size(file, size_out); 5781da177e4SLinus Torvalds } 5791da177e4SLinus Torvalds 5805dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 5815dc62b1bSWANG Cong { 5825dc62b1bSWANG Cong int err; 5835dc62b1bSWANG Cong 5848c6157b6SAnton Ivanov err = os_pread_file(fd, buf, len, offset); 5855dc62b1bSWANG Cong if (err < 0) 5865dc62b1bSWANG Cong return err; 5875dc62b1bSWANG Cong 5885dc62b1bSWANG Cong return 0; 5895dc62b1bSWANG Cong } 5905dc62b1bSWANG Cong 5915dc62b1bSWANG Cong static int backing_file_mismatch(char *file, __u64 size, time_t mtime) 5925dc62b1bSWANG Cong { 5935dc62b1bSWANG Cong unsigned long modtime; 5945dc62b1bSWANG Cong unsigned long long actual; 5955dc62b1bSWANG Cong int err; 5965dc62b1bSWANG Cong 5975dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 5985dc62b1bSWANG Cong if (err < 0) { 5995dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 6005dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 6015dc62b1bSWANG Cong return err; 6025dc62b1bSWANG Cong } 6035dc62b1bSWANG Cong 6045dc62b1bSWANG Cong err = os_file_size(file, &actual); 6055dc62b1bSWANG Cong if (err < 0) { 6065dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 6075dc62b1bSWANG Cong "err = %d\n", file, -err); 6085dc62b1bSWANG Cong return err; 6095dc62b1bSWANG Cong } 6105dc62b1bSWANG Cong 6115dc62b1bSWANG Cong if (actual != size) { 6125dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 6135dc62b1bSWANG Cong * the typecast.*/ 6145dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 6155dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 6165dc62b1bSWANG Cong return -EINVAL; 6175dc62b1bSWANG Cong } 6185dc62b1bSWANG Cong if (modtime != mtime) { 6195dc62b1bSWANG Cong printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " 6205dc62b1bSWANG Cong "backing file\n", mtime, modtime); 6215dc62b1bSWANG Cong return -EINVAL; 6225dc62b1bSWANG Cong } 6235dc62b1bSWANG Cong return 0; 6245dc62b1bSWANG Cong } 6255dc62b1bSWANG Cong 6265dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 6275dc62b1bSWANG Cong { 6285dc62b1bSWANG Cong struct uml_stat buf1, buf2; 6295dc62b1bSWANG Cong int err; 6305dc62b1bSWANG Cong 6315dc62b1bSWANG Cong if (from_cmdline == NULL) 6325dc62b1bSWANG Cong return 0; 6335dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 6345dc62b1bSWANG Cong return 0; 6355dc62b1bSWANG Cong 6365dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 6375dc62b1bSWANG Cong if (err < 0) { 6385dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 6395dc62b1bSWANG Cong -err); 6405dc62b1bSWANG Cong return 0; 6415dc62b1bSWANG Cong } 6425dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 6435dc62b1bSWANG Cong if (err < 0) { 6445dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 6455dc62b1bSWANG Cong -err); 6465dc62b1bSWANG Cong return 1; 6475dc62b1bSWANG Cong } 6485dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 6495dc62b1bSWANG Cong return 0; 6505dc62b1bSWANG Cong 6515dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 6525dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 6535dc62b1bSWANG Cong from_cmdline, from_cow, cow); 6545dc62b1bSWANG Cong return 1; 6555dc62b1bSWANG Cong } 6565dc62b1bSWANG Cong 6575dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 6585dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 6595dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6605dc62b1bSWANG Cong int *create_cow_out) 6615dc62b1bSWANG Cong { 6625dc62b1bSWANG Cong time_t mtime; 6635dc62b1bSWANG Cong unsigned long long size; 6645dc62b1bSWANG Cong __u32 version, align; 6655dc62b1bSWANG Cong char *backing_file; 6665dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6675dc62b1bSWANG Cong 6685dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6695dc62b1bSWANG Cong if (fd < 0) { 6705dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6715dc62b1bSWANG Cong *create_cow_out = 1; 6725dc62b1bSWANG Cong if (!openflags->w || 6735dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 6745dc62b1bSWANG Cong return fd; 6755dc62b1bSWANG Cong openflags->w = 0; 6765dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6775dc62b1bSWANG Cong if (fd < 0) 6785dc62b1bSWANG Cong return fd; 6795dc62b1bSWANG Cong } 6805dc62b1bSWANG Cong 6815dc62b1bSWANG Cong if (shared) 6825dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 6835dc62b1bSWANG Cong else { 6845dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 6855dc62b1bSWANG Cong if (err < 0) { 6865dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 6875dc62b1bSWANG Cong file, -err); 6885dc62b1bSWANG Cong goto out_close; 6895dc62b1bSWANG Cong } 6905dc62b1bSWANG Cong } 6915dc62b1bSWANG Cong 6925dc62b1bSWANG Cong /* Successful return case! */ 6935dc62b1bSWANG Cong if (backing_file_out == NULL) 6945dc62b1bSWANG Cong return fd; 6955dc62b1bSWANG Cong 6965dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 6975dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 6985dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 6995dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 7005dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 7015dc62b1bSWANG Cong goto out_close; 7025dc62b1bSWANG Cong } 7035dc62b1bSWANG Cong if (err) 7045dc62b1bSWANG Cong return fd; 7055dc62b1bSWANG Cong 7065dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 7075dc62b1bSWANG Cong file); 7085dc62b1bSWANG Cong 7095dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 7105dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 7115dc62b1bSWANG Cong mtime)) { 7125dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 7135dc62b1bSWANG Cong *backing_file_out); 7145dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 7155dc62b1bSWANG Cong sectorsize, align, &size); 7165dc62b1bSWANG Cong if (err) { 7175dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 7185dc62b1bSWANG Cong goto out_close; 7195dc62b1bSWANG Cong } 7205dc62b1bSWANG Cong } else { 7215dc62b1bSWANG Cong *backing_file_out = backing_file; 7225dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 7235dc62b1bSWANG Cong if (err) 7245dc62b1bSWANG Cong goto out_close; 7255dc62b1bSWANG Cong } 7265dc62b1bSWANG Cong 7275dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 7285dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 7295dc62b1bSWANG Cong 7305dc62b1bSWANG Cong return fd; 7315dc62b1bSWANG Cong out_close: 7325dc62b1bSWANG Cong os_close_file(fd); 7335dc62b1bSWANG Cong return err; 7345dc62b1bSWANG Cong } 7355dc62b1bSWANG Cong 7365dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 7375dc62b1bSWANG Cong struct openflags flags, 7385dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 7395dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 7405dc62b1bSWANG Cong { 7415dc62b1bSWANG Cong int err, fd; 7425dc62b1bSWANG Cong 7435dc62b1bSWANG Cong flags.c = 1; 7445dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 7455dc62b1bSWANG Cong if (fd < 0) { 7465dc62b1bSWANG Cong err = fd; 7475dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 7485dc62b1bSWANG Cong cow_file, -err); 7495dc62b1bSWANG Cong goto out; 7505dc62b1bSWANG Cong } 7515dc62b1bSWANG Cong 7525dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 7535dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 7545dc62b1bSWANG Cong data_offset_out); 7555dc62b1bSWANG Cong if (!err) 7565dc62b1bSWANG Cong return fd; 7575dc62b1bSWANG Cong os_close_file(fd); 7585dc62b1bSWANG Cong out: 7595dc62b1bSWANG Cong return err; 7605dc62b1bSWANG Cong } 7615dc62b1bSWANG Cong 7625f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7631da177e4SLinus Torvalds { 7647d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7657d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7661da177e4SLinus Torvalds return; 7671da177e4SLinus Torvalds 7687d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7697d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7707d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7711da177e4SLinus Torvalds } 7721da177e4SLinus Torvalds 7737d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 7741da177e4SLinus Torvalds { 7751da177e4SLinus Torvalds struct openflags flags; 7761da177e4SLinus Torvalds char **back_ptr; 7771da177e4SLinus Torvalds int err, create_cow, *create_ptr; 7780bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 7791da177e4SLinus Torvalds 7807d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 7811da177e4SLinus Torvalds create_cow = 0; 7827d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 7837d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 7840bf16bffSPaolo 'Blaisorblade' Giarrusso 7850bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 7867d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 7877d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 7886c29256cSJeff Dike create_ptr); 7891da177e4SLinus Torvalds 7900bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 7910bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 7927d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags, 1 << 9, PAGE_SIZE, 7937d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 7947d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 7957d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 7960bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 7971da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 7987d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 7991da177e4SLinus Torvalds } 8001da177e4SLinus Torvalds } 8011da177e4SLinus Torvalds 8020bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 8037d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 8040bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 8050bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 8061da177e4SLinus Torvalds } 8070bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 8081da177e4SLinus Torvalds 8097d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 810086fa5ffSMartin K. Petersen blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); 811f4768ffdSJeff Dike 8121da177e4SLinus Torvalds err = -ENOMEM; 813da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 8147d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 8151da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 8161da177e4SLinus Torvalds goto error; 8171da177e4SLinus Torvalds } 8181da177e4SLinus Torvalds flush_tlb_kernel_vm(); 8191da177e4SLinus Torvalds 8207d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 8217d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 8227d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 8231da177e4SLinus Torvalds if(err < 0) 8241da177e4SLinus Torvalds goto error; 8251da177e4SLinus Torvalds 8267d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 8271da177e4SLinus Torvalds flags.w = 0; 8287d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 8296c29256cSJeff Dike NULL, NULL, NULL, NULL); 8301da177e4SLinus Torvalds if(err < 0) goto error; 8317d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 8321da177e4SLinus Torvalds } 833dc764e50SJeff Dike return 0; 8341da177e4SLinus Torvalds error: 8357d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 836dc764e50SJeff Dike return err; 8371da177e4SLinus Torvalds } 8381da177e4SLinus Torvalds 8392e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 8402e3f5251SJeff Dike { 8418691b97bSGreg Kroah-Hartman struct ubd *ubd_dev = dev_get_drvdata(dev); 8422e3f5251SJeff Dike 8432e3f5251SJeff Dike blk_cleanup_queue(ubd_dev->queue); 8444e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 8452e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 8462e3f5251SJeff Dike } 8472e3f5251SJeff Dike 8485f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 8491da177e4SLinus Torvalds struct gendisk **disk_out) 8501da177e4SLinus Torvalds { 851d72a5783SDan Williams struct device *parent = NULL; 8521da177e4SLinus Torvalds struct gendisk *disk; 8531da177e4SLinus Torvalds 8541da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 8551da177e4SLinus Torvalds if(disk == NULL) 856dc764e50SJeff Dike return -ENOMEM; 8571da177e4SLinus Torvalds 8581da177e4SLinus Torvalds disk->major = major; 8591da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 8601da177e4SLinus Torvalds disk->fops = &ubd_blops; 8611da177e4SLinus Torvalds set_capacity(disk, size / 512); 862792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) 8631da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 864ce7b0f46SGreg Kroah-Hartman else 8651da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 8661da177e4SLinus Torvalds 8671da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 868792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) { 8697d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 8707d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 8712e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 8728691b97bSGreg Kroah-Hartman dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); 8737d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 874d72a5783SDan Williams parent = &ubd_devs[unit].pdev.dev; 8751da177e4SLinus Torvalds } 8761da177e4SLinus Torvalds 8777d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 87862f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 879fef912bfSHannes Reinecke device_add_disk(parent, disk, NULL); 8801da177e4SLinus Torvalds 8811da177e4SLinus Torvalds *disk_out = disk; 8821da177e4SLinus Torvalds return 0; 8831da177e4SLinus Torvalds } 8841da177e4SLinus Torvalds 8851da177e4SLinus Torvalds #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) 8861da177e4SLinus Torvalds 8874e6da0feSRichard Weinberger static const struct blk_mq_ops ubd_mq_ops = { 8884e6da0feSRichard Weinberger .queue_rq = ubd_queue_rq, 8894e6da0feSRichard Weinberger }; 8904e6da0feSRichard Weinberger 891f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 8921da177e4SLinus Torvalds { 8937d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 894f28169d2SJeff Dike int err = 0; 8951da177e4SLinus Torvalds 8967d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 897ec7cf783SJeff Dike goto out; 8981da177e4SLinus Torvalds 8997d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 900f28169d2SJeff Dike if(err < 0){ 901f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 90280c13749SJeff Dike goto out; 903f28169d2SJeff Dike } 9041da177e4SLinus Torvalds 9057d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 9061da177e4SLinus Torvalds 9074e6da0feSRichard Weinberger ubd_dev->tag_set.ops = &ubd_mq_ops; 9084e6da0feSRichard Weinberger ubd_dev->tag_set.queue_depth = 64; 9094e6da0feSRichard Weinberger ubd_dev->tag_set.numa_node = NUMA_NO_NODE; 9104e6da0feSRichard Weinberger ubd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; 9114e6da0feSRichard Weinberger ubd_dev->tag_set.driver_data = ubd_dev; 9124e6da0feSRichard Weinberger ubd_dev->tag_set.nr_hw_queues = 1; 913a0044bdfSJeff Dike 9144e6da0feSRichard Weinberger err = blk_mq_alloc_tag_set(&ubd_dev->tag_set); 9154e6da0feSRichard Weinberger if (err) 91680c13749SJeff Dike goto out; 9174e6da0feSRichard Weinberger 9184e6da0feSRichard Weinberger ubd_dev->queue = blk_mq_init_queue(&ubd_dev->tag_set); 9194e6da0feSRichard Weinberger if (IS_ERR(ubd_dev->queue)) { 9204e6da0feSRichard Weinberger err = PTR_ERR(ubd_dev->queue); 9214e6da0feSRichard Weinberger goto out_cleanup; 92262f96cb0SJeff Dike } 9234e6da0feSRichard Weinberger 92462f96cb0SJeff Dike ubd_dev->queue->queuedata = ubd_dev; 925f935a8ceSJens Axboe blk_queue_write_cache(ubd_dev->queue, true, false); 92662f96cb0SJeff Dike 9278a78362cSMartin K. Petersen blk_queue_max_segments(ubd_dev->queue, MAX_SG); 928792dd4fcSChristoph Hellwig err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); 92962f96cb0SJeff Dike if(err){ 93062f96cb0SJeff Dike *error_out = "Failed to register device"; 9314e6da0feSRichard Weinberger goto out_cleanup_tags; 93262f96cb0SJeff Dike } 9331da177e4SLinus Torvalds 934792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) 9355f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 9361da177e4SLinus Torvalds &fake_gendisk[n]); 9371da177e4SLinus Torvalds 93883380cc1SJeff Dike /* 93983380cc1SJeff Dike * Perhaps this should also be under the "if (fake_major)" above 94083380cc1SJeff Dike * using the fake_disk->disk_name 94183380cc1SJeff Dike */ 9421da177e4SLinus Torvalds if (fake_ide) 9431da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 9441da177e4SLinus Torvalds 945ec7cf783SJeff Dike err = 0; 946ec7cf783SJeff Dike out: 947ec7cf783SJeff Dike return err; 94862f96cb0SJeff Dike 9494e6da0feSRichard Weinberger out_cleanup_tags: 9504e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 95162f96cb0SJeff Dike out_cleanup: 95262f96cb0SJeff Dike blk_cleanup_queue(ubd_dev->queue); 95362f96cb0SJeff Dike goto out; 9541da177e4SLinus Torvalds } 9551da177e4SLinus Torvalds 956f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 9571da177e4SLinus Torvalds { 958e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 9591da177e4SLinus Torvalds 960f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 961f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 962f28169d2SJeff Dike * were set. 963f28169d2SJeff Dike */ 964970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 9651da177e4SLinus Torvalds if (str == NULL) { 966f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 967f28169d2SJeff Dike return -ENOMEM; 9681da177e4SLinus Torvalds } 969f28169d2SJeff Dike 970f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 971f28169d2SJeff Dike if (ret) 972e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 973f28169d2SJeff Dike 974e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 975e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 976d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 977e7f6552fSPaolo 'Blaisorblade' Giarrusso } 9781da177e4SLinus Torvalds 979d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 980f28169d2SJeff Dike ret = ubd_add(n, error_out); 981e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 9827d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 983d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 9841da177e4SLinus Torvalds 985e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 986e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 987e7f6552fSPaolo 'Blaisorblade' Giarrusso 988e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 989e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 990e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 9911da177e4SLinus Torvalds } 9921da177e4SLinus Torvalds 9931da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 9941da177e4SLinus Torvalds { 9957d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 9961da177e4SLinus Torvalds int n, len = 0; 9971da177e4SLinus Torvalds 9981da177e4SLinus Torvalds n = parse_unit(&name); 9991da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 10001da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 1001dc764e50SJeff Dike return -1; 10021da177e4SLinus Torvalds } 10031da177e4SLinus Torvalds 10047d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 1005d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10061da177e4SLinus Torvalds 10077d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 10081da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 10091da177e4SLinus Torvalds goto out; 10101da177e4SLinus Torvalds } 10111da177e4SLinus Torvalds 10127d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 10131da177e4SLinus Torvalds 10147d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 10151da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 10167d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 10171da177e4SLinus Torvalds } 10181da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 10191da177e4SLinus Torvalds 10201da177e4SLinus Torvalds out: 1021d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 1022dc764e50SJeff Dike return len; 10231da177e4SLinus Torvalds } 10241da177e4SLinus Torvalds 102529d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 102629d56cfeSJeff Dike { 102729d56cfeSJeff Dike int n; 102829d56cfeSJeff Dike 102929d56cfeSJeff Dike n = parse_unit(str); 103029d56cfeSJeff Dike *start_out = 0; 103129d56cfeSJeff Dike *end_out = MAX_DEV - 1; 103229d56cfeSJeff Dike return n; 103329d56cfeSJeff Dike } 103429d56cfeSJeff Dike 1035f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 10361da177e4SLinus Torvalds { 10372e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 10387d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 103929d56cfeSJeff Dike int err = -ENODEV; 10401da177e4SLinus Torvalds 1041d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10421da177e4SLinus Torvalds 10437d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 104429d56cfeSJeff Dike 10457d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 104629d56cfeSJeff Dike goto out; 104729d56cfeSJeff Dike 104829d56cfeSJeff Dike /* you cannot remove a open disk */ 104929d56cfeSJeff Dike err = -EBUSY; 10507d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 105129d56cfeSJeff Dike goto out; 105229d56cfeSJeff Dike 10531da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 1054b47d2debSJeff Dike if(disk != NULL){ 1055b47d2debSJeff Dike del_gendisk(disk); 1056b47d2debSJeff Dike put_disk(disk); 1057b47d2debSJeff Dike } 10581da177e4SLinus Torvalds 10591da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 10601da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 10611da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 10621da177e4SLinus Torvalds fake_gendisk[n] = NULL; 10631da177e4SLinus Torvalds } 10641da177e4SLinus Torvalds 10651da177e4SLinus Torvalds err = 0; 10662e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 10671da177e4SLinus Torvalds out: 1068d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 106929d56cfeSJeff Dike return err; 10701da177e4SLinus Torvalds } 10711da177e4SLinus Torvalds 1072f28169d2SJeff Dike /* All these are called by mconsole in process context and without 1073b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 1074f28169d2SJeff Dike */ 10751da177e4SLinus Torvalds static struct mc_device ubd_mc = { 107684f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 10771da177e4SLinus Torvalds .name = "ubd", 10781da177e4SLinus Torvalds .config = ubd_config, 10791da177e4SLinus Torvalds .get_config = ubd_get_config, 108029d56cfeSJeff Dike .id = ubd_id, 10811da177e4SLinus Torvalds .remove = ubd_remove, 10821da177e4SLinus Torvalds }; 10831da177e4SLinus Torvalds 1084d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 10851da177e4SLinus Torvalds { 10861da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 10871da177e4SLinus Torvalds return 0; 10881da177e4SLinus Torvalds } 10891da177e4SLinus Torvalds 10901da177e4SLinus Torvalds __initcall(ubd_mc_init); 10911da177e4SLinus Torvalds 1092d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1093d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1094d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1095d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1096b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1097d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1098d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1099b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1100b8831a1dSJeff Dike 1101dc764e50SJeff Dike return 0; 1102d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1103d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1104d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1105d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1106b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 11073ae5eaecSRussell King static struct platform_driver ubd_driver = { 11083ae5eaecSRussell King .driver = { 11091da177e4SLinus Torvalds .name = DRIVER_NAME, 11103ae5eaecSRussell King }, 11111da177e4SLinus Torvalds }; 11121da177e4SLinus Torvalds 1113d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 11141da177e4SLinus Torvalds { 1115f28169d2SJeff Dike char *error; 1116f28169d2SJeff Dike int i, err; 11171da177e4SLinus Torvalds 1118792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 11191da177e4SLinus Torvalds return -1; 11201da177e4SLinus Torvalds 1121792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 11221da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 11231da177e4SLinus Torvalds 11241da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 11251da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 11261da177e4SLinus Torvalds return -1; 11271da177e4SLinus Torvalds } 1128f88f0bdfSAnton Ivanov 11296da2ec56SKees Cook irq_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11306da2ec56SKees Cook sizeof(struct io_thread_req *), 1131f88f0bdfSAnton Ivanov GFP_KERNEL 1132f88f0bdfSAnton Ivanov ); 1133f88f0bdfSAnton Ivanov irq_remainder = 0; 1134f88f0bdfSAnton Ivanov 1135f88f0bdfSAnton Ivanov if (irq_req_buffer == NULL) { 1136f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1137f88f0bdfSAnton Ivanov return -1; 1138f88f0bdfSAnton Ivanov } 11396da2ec56SKees Cook io_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11406da2ec56SKees Cook sizeof(struct io_thread_req *), 1141f88f0bdfSAnton Ivanov GFP_KERNEL 1142f88f0bdfSAnton Ivanov ); 1143f88f0bdfSAnton Ivanov 1144f88f0bdfSAnton Ivanov io_remainder = 0; 1145f88f0bdfSAnton Ivanov 1146f88f0bdfSAnton Ivanov if (io_req_buffer == NULL) { 1147f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1148f88f0bdfSAnton Ivanov return -1; 1149f88f0bdfSAnton Ivanov } 11503ae5eaecSRussell King platform_driver_register(&ubd_driver); 1151b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1152f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1153f28169d2SJeff Dike err = ubd_add(i, &error); 1154f28169d2SJeff Dike if(err) 1155f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1156f28169d2SJeff Dike "%s\n", i, error); 1157f28169d2SJeff Dike } 1158b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 11591da177e4SLinus Torvalds return 0; 11601da177e4SLinus Torvalds } 11611da177e4SLinus Torvalds 11621da177e4SLinus Torvalds late_initcall(ubd_init); 11631da177e4SLinus Torvalds 1164d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 116591acb21fSJeff Dike unsigned long stack; 116691acb21fSJeff Dike int err; 116791acb21fSJeff Dike 116891acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 116991acb21fSJeff Dike if(global_openflags.s){ 117091acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 117191acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 117291acb21fSJeff Dike * enough. So use anyway the io thread. */ 117391acb21fSJeff Dike } 117491acb21fSJeff Dike stack = alloc_stack(0, 0); 117591acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 117691acb21fSJeff Dike &thread_fd); 117791acb21fSJeff Dike if(io_pid < 0){ 117891acb21fSJeff Dike printk(KERN_ERR 117991acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 118091acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 118191acb21fSJeff Dike io_pid = -1; 1182dc764e50SJeff Dike return 0; 118391acb21fSJeff Dike } 118491acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 1185c0b79a90SYong Zhang 0, "ubd", ubd_devs); 118691acb21fSJeff Dike if(err != 0) 118791acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1188f4c57a78SJeff Dike return 0; 118991acb21fSJeff Dike } 119091acb21fSJeff Dike 119191acb21fSJeff Dike device_initcall(ubd_driver_init); 119291acb21fSJeff Dike 1193a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 11941da177e4SLinus Torvalds { 1195a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 11967d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 11971da177e4SLinus Torvalds int err = 0; 11981da177e4SLinus Torvalds 11999a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12007d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 12017d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 12021da177e4SLinus Torvalds if(err){ 12031da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 12047d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 12051da177e4SLinus Torvalds goto out; 12061da177e4SLinus Torvalds } 12071da177e4SLinus Torvalds } 12087d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 12097d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 12102c49be99SPaolo 'Blaisorblade' Giarrusso 12112c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 12122c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1213a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 12145f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 12151da177e4SLinus Torvalds err = -EROFS; 12162c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 12171da177e4SLinus Torvalds out: 12189a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 1219dc764e50SJeff Dike return err; 12201da177e4SLinus Torvalds } 12211da177e4SLinus Torvalds 1222db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode) 12231da177e4SLinus Torvalds { 12247d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12251da177e4SLinus Torvalds 12269a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12277d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 12285f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 12299a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 12301da177e4SLinus Torvalds } 12311da177e4SLinus Torvalds 123291acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 123391acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 123491acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 123591acb21fSJeff Dike __u64 bitmap_len) 12361da177e4SLinus Torvalds { 123791acb21fSJeff Dike __u64 sector = io_offset >> 9; 123891acb21fSJeff Dike int i, update_bitmap = 0; 12391da177e4SLinus Torvalds 124091acb21fSJeff Dike for(i = 0; i < length >> 9; i++){ 124191acb21fSJeff Dike if(cow_mask != NULL) 124291acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 124391acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 124409ace81cSJeff Dike continue; 12451da177e4SLinus Torvalds 124691acb21fSJeff Dike update_bitmap = 1; 124791acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 12481da177e4SLinus Torvalds } 124991acb21fSJeff Dike 125091acb21fSJeff Dike if(!update_bitmap) 125191acb21fSJeff Dike return; 125291acb21fSJeff Dike 125391acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 125491acb21fSJeff Dike 125591acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 125691acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 125791acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 125891acb21fSJeff Dike * for the original diagnosis. 125991acb21fSJeff Dike */ 12606d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 12616d074242SJiri Olsa sizeof(unsigned long)) - 1)) 126291acb21fSJeff Dike (*cow_offset)--; 126391acb21fSJeff Dike 126491acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 126591acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 126691acb21fSJeff Dike 126791acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 126891acb21fSJeff Dike *cow_offset += bitmap_offset; 126991acb21fSJeff Dike } 127091acb21fSJeff Dike 127191acb21fSJeff Dike static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, 127291acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 127391acb21fSJeff Dike { 127491acb21fSJeff Dike __u64 sector = req->offset >> 9; 127591acb21fSJeff Dike int i; 127691acb21fSJeff Dike 127791acb21fSJeff Dike if(req->length > (sizeof(req->sector_mask) * 8) << 9) 127891acb21fSJeff Dike panic("Operation too long"); 127991acb21fSJeff Dike 128091acb21fSJeff Dike if(req->op == UBD_READ) { 128191acb21fSJeff Dike for(i = 0; i < req->length >> 9; i++){ 128291acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 128391acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 128491acb21fSJeff Dike &req->sector_mask); 128591acb21fSJeff Dike } 128691acb21fSJeff Dike } 128791acb21fSJeff Dike else cowify_bitmap(req->offset, req->length, &req->sector_mask, 128891acb21fSJeff Dike &req->cow_offset, bitmap, bitmap_offset, 128991acb21fSJeff Dike req->bitmap_words, bitmap_len); 12901da177e4SLinus Torvalds } 12911da177e4SLinus Torvalds 1292ecb0a83eSChristoph Hellwig static int ubd_queue_one_vec(struct blk_mq_hw_ctx *hctx, struct request *req, 1293ecb0a83eSChristoph Hellwig u64 off, struct bio_vec *bvec) 12941da177e4SLinus Torvalds { 1295ecb0a83eSChristoph Hellwig struct ubd *dev = hctx->queue->queuedata; 1296ecb0a83eSChristoph Hellwig struct io_thread_req *io_req; 1297ecb0a83eSChristoph Hellwig int ret; 1298ecb0a83eSChristoph Hellwig 1299ecb0a83eSChristoph Hellwig io_req = kmalloc(sizeof(struct io_thread_req), GFP_ATOMIC); 1300ecb0a83eSChristoph Hellwig if (!io_req) 1301ecb0a83eSChristoph Hellwig return -ENOMEM; 130291acb21fSJeff Dike 130362f96cb0SJeff Dike io_req->req = req; 1304ecb0a83eSChristoph Hellwig if (dev->cow.file) 1305ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->cow.fd; 1306ecb0a83eSChristoph Hellwig else 1307ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->fd; 13080033dfd9SAnton Ivanov io_req->error = 0; 1309ecb0a83eSChristoph Hellwig 1310ecb0a83eSChristoph Hellwig if (req_op(req) == REQ_OP_FLUSH) { 1311ecb0a83eSChristoph Hellwig io_req->op = UBD_FLUSH; 1312ecb0a83eSChristoph Hellwig } else { 1313ecb0a83eSChristoph Hellwig io_req->fds[1] = dev->fd; 131491acb21fSJeff Dike io_req->cow_offset = -1; 1315ecb0a83eSChristoph Hellwig io_req->offset = off; 1316ecb0a83eSChristoph Hellwig io_req->length = bvec->bv_len; 131791acb21fSJeff Dike io_req->sector_mask = 0; 1318ecb0a83eSChristoph Hellwig io_req->op = rq_data_dir(req) == READ ? UBD_READ : UBD_WRITE; 13191da177e4SLinus Torvalds io_req->offsets[0] = 0; 1320ecb0a83eSChristoph Hellwig io_req->offsets[1] = dev->cow.data_offset; 1321ecb0a83eSChristoph Hellwig io_req->buffer = page_address(bvec->bv_page) + bvec->bv_offset; 13221da177e4SLinus Torvalds io_req->sectorsize = 1 << 9; 13231da177e4SLinus Torvalds 1324ecb0a83eSChristoph Hellwig if (dev->cow.file) { 1325ecb0a83eSChristoph Hellwig cowify_req(io_req, dev->cow.bitmap, 1326ecb0a83eSChristoph Hellwig dev->cow.bitmap_offset, dev->cow.bitmap_len); 1327ecb0a83eSChristoph Hellwig } 13281da177e4SLinus Torvalds } 13291da177e4SLinus Torvalds 1330ecb0a83eSChristoph Hellwig ret = os_write_file(thread_fd, &io_req, sizeof(io_req)); 1331ecb0a83eSChristoph Hellwig if (ret != sizeof(io_req)) { 1332ecb0a83eSChristoph Hellwig if (ret != -EAGAIN) 1333ecb0a83eSChristoph Hellwig pr_err("write to io thread failed: %d\n", -ret); 1334bc1d72e7SRichard Weinberger kfree(io_req); 1335bc1d72e7SRichard Weinberger } 1336ecb0a83eSChristoph Hellwig 1337ecb0a83eSChristoph Hellwig return ret; 1338bc1d72e7SRichard Weinberger } 1339bc1d72e7SRichard Weinberger 13404e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 13414e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd) 13421da177e4SLinus Torvalds { 13436961cd4dSJens Axboe struct ubd *ubd_dev = hctx->queue->queuedata; 13444e6da0feSRichard Weinberger struct request *req = bd->rq; 1345ecb0a83eSChristoph Hellwig int ret = 0; 13461da177e4SLinus Torvalds 13474e6da0feSRichard Weinberger blk_mq_start_request(req); 1348a0044bdfSJeff Dike 13496961cd4dSJens Axboe spin_lock_irq(&ubd_dev->lock); 13506961cd4dSJens Axboe 13513a5e02ceSMike Christie if (req_op(req) == REQ_OP_FLUSH) { 1352ecb0a83eSChristoph Hellwig ret = ubd_queue_one_vec(hctx, req, 0, NULL); 1353ecb0a83eSChristoph Hellwig } else { 1354ecb0a83eSChristoph Hellwig struct req_iterator iter; 1355ecb0a83eSChristoph Hellwig struct bio_vec bvec; 1356ecb0a83eSChristoph Hellwig u64 off = (u64)blk_rq_pos(req) << 9; 1357ecb0a83eSChristoph Hellwig 1358ecb0a83eSChristoph Hellwig rq_for_each_segment(bvec, req, iter) { 1359ecb0a83eSChristoph Hellwig ret = ubd_queue_one_vec(hctx, req, off, &bvec); 1360ecb0a83eSChristoph Hellwig if (ret < 0) 1361ecb0a83eSChristoph Hellwig goto out; 1362ecb0a83eSChristoph Hellwig off += bvec.bv_len; 1363ecb0a83eSChristoph Hellwig } 1364ecb0a83eSChristoph Hellwig } 1365ecb0a83eSChristoph Hellwig out: 13666961cd4dSJens Axboe spin_unlock_irq(&ubd_dev->lock); 13676961cd4dSJens Axboe 13686961cd4dSJens Axboe if (ret < 0) 13694e6da0feSRichard Weinberger blk_mq_requeue_request(req, true); 13706961cd4dSJens Axboe 13714e6da0feSRichard Weinberger return BLK_STS_OK; 137291acb21fSJeff Dike } 13734e6da0feSRichard Weinberger 1374a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1375a885c8c4SChristoph Hellwig { 13767d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1377a885c8c4SChristoph Hellwig 1378a885c8c4SChristoph Hellwig geo->heads = 128; 1379a885c8c4SChristoph Hellwig geo->sectors = 32; 13807d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1381a885c8c4SChristoph Hellwig return 0; 1382a885c8c4SChristoph Hellwig } 1383a885c8c4SChristoph Hellwig 1384a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 13851da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 13861da177e4SLinus Torvalds { 1387a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 138873855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 13891da177e4SLinus Torvalds 13901da177e4SLinus Torvalds switch (cmd) { 13911da177e4SLinus Torvalds struct cdrom_volctrl volume; 13921da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 139373855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 139473855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 139573855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 139673855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 13971da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 13981da177e4SLinus Torvalds sizeof(ubd_id))) 1399dc764e50SJeff Dike return -EFAULT; 1400dc764e50SJeff Dike return 0; 14011da177e4SLinus Torvalds 14021da177e4SLinus Torvalds case CDROMVOLREAD: 14031da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1404dc764e50SJeff Dike return -EFAULT; 14051da177e4SLinus Torvalds volume.channel0 = 255; 14061da177e4SLinus Torvalds volume.channel1 = 255; 14071da177e4SLinus Torvalds volume.channel2 = 255; 14081da177e4SLinus Torvalds volume.channel3 = 255; 14091da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1410dc764e50SJeff Dike return -EFAULT; 1411dc764e50SJeff Dike return 0; 14121da177e4SLinus Torvalds } 1413dc764e50SJeff Dike return -EINVAL; 14141da177e4SLinus Torvalds } 14151da177e4SLinus Torvalds 141691acb21fSJeff Dike static int update_bitmap(struct io_thread_req *req) 14171da177e4SLinus Torvalds { 141891acb21fSJeff Dike int n; 141991acb21fSJeff Dike 142091acb21fSJeff Dike if(req->cow_offset == -1) 1421dc764e50SJeff Dike return 0; 142291acb21fSJeff Dike 14238c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[1], &req->bitmap_words, 14248c6157b6SAnton Ivanov sizeof(req->bitmap_words), req->cow_offset); 142591acb21fSJeff Dike if(n != sizeof(req->bitmap_words)){ 142691acb21fSJeff Dike printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, 142791acb21fSJeff Dike req->fds[1]); 1428dc764e50SJeff Dike return 1; 142991acb21fSJeff Dike } 143091acb21fSJeff Dike 1431dc764e50SJeff Dike return 0; 143291acb21fSJeff Dike } 143391acb21fSJeff Dike 14345dc62b1bSWANG Cong static void do_io(struct io_thread_req *req) 143591acb21fSJeff Dike { 14361da177e4SLinus Torvalds char *buf; 143791acb21fSJeff Dike unsigned long len; 143891acb21fSJeff Dike int n, nsectors, start, end, bit; 14391da177e4SLinus Torvalds __u64 off; 14401da177e4SLinus Torvalds 1441805f11a0SRichard Weinberger if (req->op == UBD_FLUSH) { 1442805f11a0SRichard Weinberger /* fds[0] is always either the rw image or our cow file */ 1443805f11a0SRichard Weinberger n = os_sync_file(req->fds[0]); 1444805f11a0SRichard Weinberger if (n != 0) { 1445805f11a0SRichard Weinberger printk("do_io - sync failed err = %d " 1446805f11a0SRichard Weinberger "fd = %d\n", -n, req->fds[0]); 1447805f11a0SRichard Weinberger req->error = 1; 1448805f11a0SRichard Weinberger } 1449805f11a0SRichard Weinberger return; 1450805f11a0SRichard Weinberger } 1451805f11a0SRichard Weinberger 14521da177e4SLinus Torvalds nsectors = req->length / req->sectorsize; 14531da177e4SLinus Torvalds start = 0; 14541da177e4SLinus Torvalds do { 145591acb21fSJeff Dike bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); 14561da177e4SLinus Torvalds end = start; 14571da177e4SLinus Torvalds while((end < nsectors) && 145891acb21fSJeff Dike (ubd_test_bit(end, (unsigned char *) 145991acb21fSJeff Dike &req->sector_mask) == bit)) 14601da177e4SLinus Torvalds end++; 14611da177e4SLinus Torvalds 146291acb21fSJeff Dike off = req->offset + req->offsets[bit] + 14631da177e4SLinus Torvalds start * req->sectorsize; 14641da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 14651da177e4SLinus Torvalds buf = &req->buffer[start * req->sectorsize]; 14661da177e4SLinus Torvalds 146791acb21fSJeff Dike if(req->op == UBD_READ){ 146891acb21fSJeff Dike n = 0; 146991acb21fSJeff Dike do { 147091acb21fSJeff Dike buf = &buf[n]; 147191acb21fSJeff Dike len -= n; 14728c6157b6SAnton Ivanov n = os_pread_file(req->fds[bit], buf, len, off); 147391acb21fSJeff Dike if (n < 0) { 147491acb21fSJeff Dike printk("do_io - read failed, err = %d " 147591acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 14761da177e4SLinus Torvalds req->error = 1; 14771da177e4SLinus Torvalds return; 14781da177e4SLinus Torvalds } 147991acb21fSJeff Dike } while((n < len) && (n != 0)); 148091acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 148191acb21fSJeff Dike } else { 14828c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[bit], buf, len, off); 148391acb21fSJeff Dike if(n != len){ 148491acb21fSJeff Dike printk("do_io - write failed err = %d " 148591acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 148691acb21fSJeff Dike req->error = 1; 148791acb21fSJeff Dike return; 148891acb21fSJeff Dike } 148991acb21fSJeff Dike } 14901da177e4SLinus Torvalds 14911da177e4SLinus Torvalds start = end; 14921da177e4SLinus Torvalds } while(start < nsectors); 149391acb21fSJeff Dike 149491acb21fSJeff Dike req->error = update_bitmap(req); 14951da177e4SLinus Torvalds } 149691acb21fSJeff Dike 149791acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 149891acb21fSJeff Dike * from ubd_init, which is an initcall. 149991acb21fSJeff Dike */ 150091acb21fSJeff Dike int kernel_fd = -1; 150191acb21fSJeff Dike 1502d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1503d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 150491acb21fSJeff Dike 150591acb21fSJeff Dike int io_thread(void *arg) 150691acb21fSJeff Dike { 1507f88f0bdfSAnton Ivanov int n, count, written, res; 150891acb21fSJeff Dike 150991d44ff8SRichard Weinberger os_fix_helper_signals(); 151091d44ff8SRichard Weinberger 151191acb21fSJeff Dike while(1){ 1512f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 1513f88f0bdfSAnton Ivanov kernel_fd, 1514f88f0bdfSAnton Ivanov io_req_buffer, 1515f88f0bdfSAnton Ivanov &io_remainder, 1516f88f0bdfSAnton Ivanov &io_remainder_size, 1517f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 1518f88f0bdfSAnton Ivanov ); 1519f88f0bdfSAnton Ivanov if (n < 0) { 1520f88f0bdfSAnton Ivanov if (n == -EAGAIN) { 1521f88f0bdfSAnton Ivanov ubd_read_poll(-1); 1522f88f0bdfSAnton Ivanov continue; 1523f88f0bdfSAnton Ivanov } else { 1524f88f0bdfSAnton Ivanov printk("io_thread - read failed, fd = %d, " 1525f88f0bdfSAnton Ivanov "err = %d," 1526f88f0bdfSAnton Ivanov "reminder = %d\n", 1527f88f0bdfSAnton Ivanov kernel_fd, -n, io_remainder_size); 1528f88f0bdfSAnton Ivanov } 1529f88f0bdfSAnton Ivanov } 1530f88f0bdfSAnton Ivanov 1531f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 1532f88f0bdfSAnton Ivanov io_count++; 1533f88f0bdfSAnton Ivanov do_io((*io_req_buffer)[count]); 1534f88f0bdfSAnton Ivanov } 1535f88f0bdfSAnton Ivanov 1536f88f0bdfSAnton Ivanov written = 0; 1537f88f0bdfSAnton Ivanov 1538f88f0bdfSAnton Ivanov do { 1539f88f0bdfSAnton Ivanov res = os_write_file(kernel_fd, ((char *) io_req_buffer) + written, n); 1540ff6a1798SAnton Ivanov if (res >= 0) { 1541f88f0bdfSAnton Ivanov written += res; 1542f88f0bdfSAnton Ivanov } else { 1543f88f0bdfSAnton Ivanov if (res != -EAGAIN) { 1544ff6a1798SAnton Ivanov printk("io_thread - write failed, fd = %d, " 154591acb21fSJeff Dike "err = %d\n", kernel_fd, -n); 154691acb21fSJeff Dike } 154791acb21fSJeff Dike } 1548f88f0bdfSAnton Ivanov if (written < n) { 1549f88f0bdfSAnton Ivanov ubd_write_poll(-1); 1550f88f0bdfSAnton Ivanov } 1551f88f0bdfSAnton Ivanov } while (written < n); 155291acb21fSJeff Dike } 155391acb21fSJeff Dike 15541b57e9c2SJeff Dike return 0; 15551b57e9c2SJeff Dike } 1556