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 46a43c8316SAnton Ivanov /* Max request size is determined by sector mask - 32K */ 47a43c8316SAnton Ivanov #define UBD_MAX_REQUEST (8 * sizeof(long)) 481da177e4SLinus Torvalds 491da177e4SLinus Torvalds struct io_thread_req { 5062f96cb0SJeff Dike struct request *req; 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]; 514a0044bdfSJeff Dike 515a43c8316SAnton Ivanov if (!blk_update_request(io_req->req, io_req->error, io_req->length)) 516a43c8316SAnton Ivanov __blk_mq_end_request(io_req->req, io_req->error); 5174e6da0feSRichard Weinberger 5184e6da0feSRichard Weinberger kfree(io_req); 519a0044bdfSJeff Dike } 52091acb21fSJeff Dike } 5214e6da0feSRichard Weinberger reactivate_fd(thread_fd, UBD_IRQ); 5224e6da0feSRichard Weinberger } 5234e6da0feSRichard Weinberger 5247bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 5251da177e4SLinus Torvalds { 52691acb21fSJeff Dike ubd_handler(); 527dc764e50SJeff Dike return IRQ_HANDLED; 5281da177e4SLinus Torvalds } 5291da177e4SLinus Torvalds 53091acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 53191acb21fSJeff Dike static int io_pid = -1; 53291acb21fSJeff Dike 5335dc62b1bSWANG Cong static void kill_io_thread(void) 53491acb21fSJeff Dike { 53591acb21fSJeff Dike if(io_pid != -1) 53691acb21fSJeff Dike os_kill_process(io_pid, 1); 53791acb21fSJeff Dike } 53891acb21fSJeff Dike 53991acb21fSJeff Dike __uml_exitcall(kill_io_thread); 54091acb21fSJeff Dike 541d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5421da177e4SLinus Torvalds { 5431da177e4SLinus Torvalds char *file; 54485356398SRichard Weinberger int fd; 54585356398SRichard Weinberger int err; 5461da177e4SLinus Torvalds 54785356398SRichard Weinberger __u32 version; 54885356398SRichard Weinberger __u32 align; 54985356398SRichard Weinberger char *backing_file; 55085356398SRichard Weinberger time_t mtime; 55185356398SRichard Weinberger unsigned long long size; 55285356398SRichard Weinberger int sector_size; 55385356398SRichard Weinberger int bitmap_offset; 55485356398SRichard Weinberger 55585356398SRichard Weinberger if (ubd_dev->file && ubd_dev->cow.file) { 55685356398SRichard Weinberger file = ubd_dev->cow.file; 55785356398SRichard Weinberger 55885356398SRichard Weinberger goto out; 55985356398SRichard Weinberger } 56085356398SRichard Weinberger 561d4afcba9SMartin Pärtel fd = os_open_file(ubd_dev->file, of_read(OPENFLAGS()), 0); 56285356398SRichard Weinberger if (fd < 0) 56385356398SRichard Weinberger return fd; 56485356398SRichard Weinberger 56585356398SRichard Weinberger err = read_cow_header(file_reader, &fd, &version, &backing_file, \ 56685356398SRichard Weinberger &mtime, &size, §or_size, &align, &bitmap_offset); 56785356398SRichard Weinberger os_close_file(fd); 56885356398SRichard Weinberger 56985356398SRichard Weinberger if(err == -EINVAL) 57085356398SRichard Weinberger file = ubd_dev->file; 57185356398SRichard Weinberger else 57285356398SRichard Weinberger file = backing_file; 57385356398SRichard Weinberger 57485356398SRichard Weinberger out: 575dc764e50SJeff Dike return os_file_size(file, size_out); 5761da177e4SLinus Torvalds } 5771da177e4SLinus Torvalds 5785dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 5795dc62b1bSWANG Cong { 5805dc62b1bSWANG Cong int err; 5815dc62b1bSWANG Cong 5828c6157b6SAnton Ivanov err = os_pread_file(fd, buf, len, offset); 5835dc62b1bSWANG Cong if (err < 0) 5845dc62b1bSWANG Cong return err; 5855dc62b1bSWANG Cong 5865dc62b1bSWANG Cong return 0; 5875dc62b1bSWANG Cong } 5885dc62b1bSWANG Cong 5895dc62b1bSWANG Cong static int backing_file_mismatch(char *file, __u64 size, time_t mtime) 5905dc62b1bSWANG Cong { 5915dc62b1bSWANG Cong unsigned long modtime; 5925dc62b1bSWANG Cong unsigned long long actual; 5935dc62b1bSWANG Cong int err; 5945dc62b1bSWANG Cong 5955dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 5965dc62b1bSWANG Cong if (err < 0) { 5975dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 5985dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 5995dc62b1bSWANG Cong return err; 6005dc62b1bSWANG Cong } 6015dc62b1bSWANG Cong 6025dc62b1bSWANG Cong err = os_file_size(file, &actual); 6035dc62b1bSWANG Cong if (err < 0) { 6045dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 6055dc62b1bSWANG Cong "err = %d\n", file, -err); 6065dc62b1bSWANG Cong return err; 6075dc62b1bSWANG Cong } 6085dc62b1bSWANG Cong 6095dc62b1bSWANG Cong if (actual != size) { 6105dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 6115dc62b1bSWANG Cong * the typecast.*/ 6125dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 6135dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 6145dc62b1bSWANG Cong return -EINVAL; 6155dc62b1bSWANG Cong } 6165dc62b1bSWANG Cong if (modtime != mtime) { 6175dc62b1bSWANG Cong printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " 6185dc62b1bSWANG Cong "backing file\n", mtime, modtime); 6195dc62b1bSWANG Cong return -EINVAL; 6205dc62b1bSWANG Cong } 6215dc62b1bSWANG Cong return 0; 6225dc62b1bSWANG Cong } 6235dc62b1bSWANG Cong 6245dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 6255dc62b1bSWANG Cong { 6265dc62b1bSWANG Cong struct uml_stat buf1, buf2; 6275dc62b1bSWANG Cong int err; 6285dc62b1bSWANG Cong 6295dc62b1bSWANG Cong if (from_cmdline == NULL) 6305dc62b1bSWANG Cong return 0; 6315dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 6325dc62b1bSWANG Cong return 0; 6335dc62b1bSWANG Cong 6345dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 6355dc62b1bSWANG Cong if (err < 0) { 6365dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 6375dc62b1bSWANG Cong -err); 6385dc62b1bSWANG Cong return 0; 6395dc62b1bSWANG Cong } 6405dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 6415dc62b1bSWANG Cong if (err < 0) { 6425dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 6435dc62b1bSWANG Cong -err); 6445dc62b1bSWANG Cong return 1; 6455dc62b1bSWANG Cong } 6465dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 6475dc62b1bSWANG Cong return 0; 6485dc62b1bSWANG Cong 6495dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 6505dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 6515dc62b1bSWANG Cong from_cmdline, from_cow, cow); 6525dc62b1bSWANG Cong return 1; 6535dc62b1bSWANG Cong } 6545dc62b1bSWANG Cong 6555dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 6565dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 6575dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6585dc62b1bSWANG Cong int *create_cow_out) 6595dc62b1bSWANG Cong { 6605dc62b1bSWANG Cong time_t mtime; 6615dc62b1bSWANG Cong unsigned long long size; 6625dc62b1bSWANG Cong __u32 version, align; 6635dc62b1bSWANG Cong char *backing_file; 6645dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6655dc62b1bSWANG Cong 6665dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6675dc62b1bSWANG Cong if (fd < 0) { 6685dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6695dc62b1bSWANG Cong *create_cow_out = 1; 6705dc62b1bSWANG Cong if (!openflags->w || 6715dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 6725dc62b1bSWANG Cong return fd; 6735dc62b1bSWANG Cong openflags->w = 0; 6745dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6755dc62b1bSWANG Cong if (fd < 0) 6765dc62b1bSWANG Cong return fd; 6775dc62b1bSWANG Cong } 6785dc62b1bSWANG Cong 6795dc62b1bSWANG Cong if (shared) 6805dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 6815dc62b1bSWANG Cong else { 6825dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 6835dc62b1bSWANG Cong if (err < 0) { 6845dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 6855dc62b1bSWANG Cong file, -err); 6865dc62b1bSWANG Cong goto out_close; 6875dc62b1bSWANG Cong } 6885dc62b1bSWANG Cong } 6895dc62b1bSWANG Cong 6905dc62b1bSWANG Cong /* Successful return case! */ 6915dc62b1bSWANG Cong if (backing_file_out == NULL) 6925dc62b1bSWANG Cong return fd; 6935dc62b1bSWANG Cong 6945dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 6955dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 6965dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 6975dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 6985dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 6995dc62b1bSWANG Cong goto out_close; 7005dc62b1bSWANG Cong } 7015dc62b1bSWANG Cong if (err) 7025dc62b1bSWANG Cong return fd; 7035dc62b1bSWANG Cong 7045dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 7055dc62b1bSWANG Cong file); 7065dc62b1bSWANG Cong 7075dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 7085dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 7095dc62b1bSWANG Cong mtime)) { 7105dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 7115dc62b1bSWANG Cong *backing_file_out); 7125dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 7135dc62b1bSWANG Cong sectorsize, align, &size); 7145dc62b1bSWANG Cong if (err) { 7155dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 7165dc62b1bSWANG Cong goto out_close; 7175dc62b1bSWANG Cong } 7185dc62b1bSWANG Cong } else { 7195dc62b1bSWANG Cong *backing_file_out = backing_file; 7205dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 7215dc62b1bSWANG Cong if (err) 7225dc62b1bSWANG Cong goto out_close; 7235dc62b1bSWANG Cong } 7245dc62b1bSWANG Cong 7255dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 7265dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 7275dc62b1bSWANG Cong 7285dc62b1bSWANG Cong return fd; 7295dc62b1bSWANG Cong out_close: 7305dc62b1bSWANG Cong os_close_file(fd); 7315dc62b1bSWANG Cong return err; 7325dc62b1bSWANG Cong } 7335dc62b1bSWANG Cong 7345dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 7355dc62b1bSWANG Cong struct openflags flags, 7365dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 7375dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 7385dc62b1bSWANG Cong { 7395dc62b1bSWANG Cong int err, fd; 7405dc62b1bSWANG Cong 7415dc62b1bSWANG Cong flags.c = 1; 7425dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 7435dc62b1bSWANG Cong if (fd < 0) { 7445dc62b1bSWANG Cong err = fd; 7455dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 7465dc62b1bSWANG Cong cow_file, -err); 7475dc62b1bSWANG Cong goto out; 7485dc62b1bSWANG Cong } 7495dc62b1bSWANG Cong 7505dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 7515dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 7525dc62b1bSWANG Cong data_offset_out); 7535dc62b1bSWANG Cong if (!err) 7545dc62b1bSWANG Cong return fd; 7555dc62b1bSWANG Cong os_close_file(fd); 7565dc62b1bSWANG Cong out: 7575dc62b1bSWANG Cong return err; 7585dc62b1bSWANG Cong } 7595dc62b1bSWANG Cong 7605f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7611da177e4SLinus Torvalds { 7627d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7637d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7641da177e4SLinus Torvalds return; 7651da177e4SLinus Torvalds 7667d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7677d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7687d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7691da177e4SLinus Torvalds } 7701da177e4SLinus Torvalds 7717d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 7721da177e4SLinus Torvalds { 7731da177e4SLinus Torvalds struct openflags flags; 7741da177e4SLinus Torvalds char **back_ptr; 7751da177e4SLinus Torvalds int err, create_cow, *create_ptr; 7760bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 7771da177e4SLinus Torvalds 7787d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 7791da177e4SLinus Torvalds create_cow = 0; 7807d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 7817d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 7820bf16bffSPaolo 'Blaisorblade' Giarrusso 7830bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 7847d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 7857d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 7866c29256cSJeff Dike create_ptr); 7871da177e4SLinus Torvalds 7880bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 7890bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 790a43c8316SAnton Ivanov ubd_dev->openflags, SECTOR_SIZE, PAGE_SIZE, 7917d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 7927d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 7937d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 7940bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 7951da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 7967d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 7971da177e4SLinus Torvalds } 7981da177e4SLinus Torvalds } 7991da177e4SLinus Torvalds 8000bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 8017d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 8020bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 8030bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 8041da177e4SLinus Torvalds } 8050bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 8061da177e4SLinus Torvalds 8077d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 808086fa5ffSMartin K. Petersen blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); 809f4768ffdSJeff Dike 8101da177e4SLinus Torvalds err = -ENOMEM; 811da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 8127d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 8131da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 8141da177e4SLinus Torvalds goto error; 8151da177e4SLinus Torvalds } 8161da177e4SLinus Torvalds flush_tlb_kernel_vm(); 8171da177e4SLinus Torvalds 8187d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 8197d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 8207d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 8211da177e4SLinus Torvalds if(err < 0) 8221da177e4SLinus Torvalds goto error; 8231da177e4SLinus Torvalds 8247d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 8251da177e4SLinus Torvalds flags.w = 0; 8267d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 8276c29256cSJeff Dike NULL, NULL, NULL, NULL); 8281da177e4SLinus Torvalds if(err < 0) goto error; 8297d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 8301da177e4SLinus Torvalds } 831a43c8316SAnton Ivanov blk_queue_flag_set(QUEUE_FLAG_NONROT, ubd_dev->queue); 832dc764e50SJeff Dike return 0; 8331da177e4SLinus Torvalds error: 8347d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 835dc764e50SJeff Dike return err; 8361da177e4SLinus Torvalds } 8371da177e4SLinus Torvalds 8382e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 8392e3f5251SJeff Dike { 8408691b97bSGreg Kroah-Hartman struct ubd *ubd_dev = dev_get_drvdata(dev); 8412e3f5251SJeff Dike 8422e3f5251SJeff Dike blk_cleanup_queue(ubd_dev->queue); 8434e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 8442e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 8452e3f5251SJeff Dike } 8462e3f5251SJeff Dike 8475f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 8481da177e4SLinus Torvalds struct gendisk **disk_out) 8491da177e4SLinus Torvalds { 850d72a5783SDan Williams struct device *parent = NULL; 8511da177e4SLinus Torvalds struct gendisk *disk; 8521da177e4SLinus Torvalds 8531da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 8541da177e4SLinus Torvalds if(disk == NULL) 855dc764e50SJeff Dike return -ENOMEM; 8561da177e4SLinus Torvalds 8571da177e4SLinus Torvalds disk->major = major; 8581da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 8591da177e4SLinus Torvalds disk->fops = &ubd_blops; 8601da177e4SLinus Torvalds set_capacity(disk, size / 512); 861792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) 8621da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 863ce7b0f46SGreg Kroah-Hartman else 8641da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 8651da177e4SLinus Torvalds 8661da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 867792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) { 8687d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 8697d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 8702e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 8718691b97bSGreg Kroah-Hartman dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); 8727d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 873d72a5783SDan Williams parent = &ubd_devs[unit].pdev.dev; 8741da177e4SLinus Torvalds } 8751da177e4SLinus Torvalds 8767d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 87762f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 878fef912bfSHannes Reinecke device_add_disk(parent, disk, NULL); 8791da177e4SLinus Torvalds 8801da177e4SLinus Torvalds *disk_out = disk; 8811da177e4SLinus Torvalds return 0; 8821da177e4SLinus Torvalds } 8831da177e4SLinus Torvalds 884a43c8316SAnton Ivanov #define ROUND_BLOCK(n) ((n + (SECTOR_SIZE - 1)) & (-SECTOR_SIZE)) 8851da177e4SLinus Torvalds 8864e6da0feSRichard Weinberger static const struct blk_mq_ops ubd_mq_ops = { 8874e6da0feSRichard Weinberger .queue_rq = ubd_queue_rq, 8884e6da0feSRichard Weinberger }; 8894e6da0feSRichard Weinberger 890f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 8911da177e4SLinus Torvalds { 8927d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 893f28169d2SJeff Dike int err = 0; 8941da177e4SLinus Torvalds 8957d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 896ec7cf783SJeff Dike goto out; 8971da177e4SLinus Torvalds 8987d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 899f28169d2SJeff Dike if(err < 0){ 900f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 90180c13749SJeff Dike goto out; 902f28169d2SJeff Dike } 9031da177e4SLinus Torvalds 9047d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 9051da177e4SLinus Torvalds 9064e6da0feSRichard Weinberger ubd_dev->tag_set.ops = &ubd_mq_ops; 9074e6da0feSRichard Weinberger ubd_dev->tag_set.queue_depth = 64; 9084e6da0feSRichard Weinberger ubd_dev->tag_set.numa_node = NUMA_NO_NODE; 9094e6da0feSRichard Weinberger ubd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; 9104e6da0feSRichard Weinberger ubd_dev->tag_set.driver_data = ubd_dev; 9114e6da0feSRichard Weinberger ubd_dev->tag_set.nr_hw_queues = 1; 912a0044bdfSJeff Dike 9134e6da0feSRichard Weinberger err = blk_mq_alloc_tag_set(&ubd_dev->tag_set); 9144e6da0feSRichard Weinberger if (err) 91580c13749SJeff Dike goto out; 9164e6da0feSRichard Weinberger 9174e6da0feSRichard Weinberger ubd_dev->queue = blk_mq_init_queue(&ubd_dev->tag_set); 9184e6da0feSRichard Weinberger if (IS_ERR(ubd_dev->queue)) { 9194e6da0feSRichard Weinberger err = PTR_ERR(ubd_dev->queue); 9204e6da0feSRichard Weinberger goto out_cleanup; 92162f96cb0SJeff Dike } 9224e6da0feSRichard Weinberger 92362f96cb0SJeff Dike ubd_dev->queue->queuedata = ubd_dev; 924f935a8ceSJens Axboe blk_queue_write_cache(ubd_dev->queue, true, false); 92562f96cb0SJeff Dike 9268a78362cSMartin K. Petersen blk_queue_max_segments(ubd_dev->queue, MAX_SG); 927792dd4fcSChristoph Hellwig err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); 92862f96cb0SJeff Dike if(err){ 92962f96cb0SJeff Dike *error_out = "Failed to register device"; 9304e6da0feSRichard Weinberger goto out_cleanup_tags; 93162f96cb0SJeff Dike } 9321da177e4SLinus Torvalds 933792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) 9345f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 9351da177e4SLinus Torvalds &fake_gendisk[n]); 9361da177e4SLinus Torvalds 93783380cc1SJeff Dike /* 93883380cc1SJeff Dike * Perhaps this should also be under the "if (fake_major)" above 93983380cc1SJeff Dike * using the fake_disk->disk_name 94083380cc1SJeff Dike */ 9411da177e4SLinus Torvalds if (fake_ide) 9421da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 9431da177e4SLinus Torvalds 944ec7cf783SJeff Dike err = 0; 945ec7cf783SJeff Dike out: 946ec7cf783SJeff Dike return err; 94762f96cb0SJeff Dike 9484e6da0feSRichard Weinberger out_cleanup_tags: 9494e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 95062f96cb0SJeff Dike out_cleanup: 95162f96cb0SJeff Dike blk_cleanup_queue(ubd_dev->queue); 95262f96cb0SJeff Dike goto out; 9531da177e4SLinus Torvalds } 9541da177e4SLinus Torvalds 955f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 9561da177e4SLinus Torvalds { 957e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 9581da177e4SLinus Torvalds 959f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 960f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 961f28169d2SJeff Dike * were set. 962f28169d2SJeff Dike */ 963970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 9641da177e4SLinus Torvalds if (str == NULL) { 965f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 966f28169d2SJeff Dike return -ENOMEM; 9671da177e4SLinus Torvalds } 968f28169d2SJeff Dike 969f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 970f28169d2SJeff Dike if (ret) 971e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 972f28169d2SJeff Dike 973e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 974e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 975d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 976e7f6552fSPaolo 'Blaisorblade' Giarrusso } 9771da177e4SLinus Torvalds 978d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 979f28169d2SJeff Dike ret = ubd_add(n, error_out); 980e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 9817d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 982d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 9831da177e4SLinus Torvalds 984e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 985e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 986e7f6552fSPaolo 'Blaisorblade' Giarrusso 987e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 988e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 989e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 9901da177e4SLinus Torvalds } 9911da177e4SLinus Torvalds 9921da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 9931da177e4SLinus Torvalds { 9947d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 9951da177e4SLinus Torvalds int n, len = 0; 9961da177e4SLinus Torvalds 9971da177e4SLinus Torvalds n = parse_unit(&name); 9981da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 9991da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 1000dc764e50SJeff Dike return -1; 10011da177e4SLinus Torvalds } 10021da177e4SLinus Torvalds 10037d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 1004d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10051da177e4SLinus Torvalds 10067d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 10071da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 10081da177e4SLinus Torvalds goto out; 10091da177e4SLinus Torvalds } 10101da177e4SLinus Torvalds 10117d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 10121da177e4SLinus Torvalds 10137d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 10141da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 10157d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 10161da177e4SLinus Torvalds } 10171da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 10181da177e4SLinus Torvalds 10191da177e4SLinus Torvalds out: 1020d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 1021dc764e50SJeff Dike return len; 10221da177e4SLinus Torvalds } 10231da177e4SLinus Torvalds 102429d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 102529d56cfeSJeff Dike { 102629d56cfeSJeff Dike int n; 102729d56cfeSJeff Dike 102829d56cfeSJeff Dike n = parse_unit(str); 102929d56cfeSJeff Dike *start_out = 0; 103029d56cfeSJeff Dike *end_out = MAX_DEV - 1; 103129d56cfeSJeff Dike return n; 103229d56cfeSJeff Dike } 103329d56cfeSJeff Dike 1034f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 10351da177e4SLinus Torvalds { 10362e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 10377d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 103829d56cfeSJeff Dike int err = -ENODEV; 10391da177e4SLinus Torvalds 1040d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10411da177e4SLinus Torvalds 10427d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 104329d56cfeSJeff Dike 10447d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 104529d56cfeSJeff Dike goto out; 104629d56cfeSJeff Dike 104729d56cfeSJeff Dike /* you cannot remove a open disk */ 104829d56cfeSJeff Dike err = -EBUSY; 10497d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 105029d56cfeSJeff Dike goto out; 105129d56cfeSJeff Dike 10521da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 1053b47d2debSJeff Dike if(disk != NULL){ 1054b47d2debSJeff Dike del_gendisk(disk); 1055b47d2debSJeff Dike put_disk(disk); 1056b47d2debSJeff Dike } 10571da177e4SLinus Torvalds 10581da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 10591da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 10601da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 10611da177e4SLinus Torvalds fake_gendisk[n] = NULL; 10621da177e4SLinus Torvalds } 10631da177e4SLinus Torvalds 10641da177e4SLinus Torvalds err = 0; 10652e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 10661da177e4SLinus Torvalds out: 1067d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 106829d56cfeSJeff Dike return err; 10691da177e4SLinus Torvalds } 10701da177e4SLinus Torvalds 1071f28169d2SJeff Dike /* All these are called by mconsole in process context and without 1072b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 1073f28169d2SJeff Dike */ 10741da177e4SLinus Torvalds static struct mc_device ubd_mc = { 107584f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 10761da177e4SLinus Torvalds .name = "ubd", 10771da177e4SLinus Torvalds .config = ubd_config, 10781da177e4SLinus Torvalds .get_config = ubd_get_config, 107929d56cfeSJeff Dike .id = ubd_id, 10801da177e4SLinus Torvalds .remove = ubd_remove, 10811da177e4SLinus Torvalds }; 10821da177e4SLinus Torvalds 1083d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 10841da177e4SLinus Torvalds { 10851da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 10861da177e4SLinus Torvalds return 0; 10871da177e4SLinus Torvalds } 10881da177e4SLinus Torvalds 10891da177e4SLinus Torvalds __initcall(ubd_mc_init); 10901da177e4SLinus Torvalds 1091d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1092d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1093d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1094d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1095b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1096d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1097d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1098b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1099b8831a1dSJeff Dike 1100dc764e50SJeff Dike return 0; 1101d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1102d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1103d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1104d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1105b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 11063ae5eaecSRussell King static struct platform_driver ubd_driver = { 11073ae5eaecSRussell King .driver = { 11081da177e4SLinus Torvalds .name = DRIVER_NAME, 11093ae5eaecSRussell King }, 11101da177e4SLinus Torvalds }; 11111da177e4SLinus Torvalds 1112d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 11131da177e4SLinus Torvalds { 1114f28169d2SJeff Dike char *error; 1115f28169d2SJeff Dike int i, err; 11161da177e4SLinus Torvalds 1117792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 11181da177e4SLinus Torvalds return -1; 11191da177e4SLinus Torvalds 1120792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 11211da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 11221da177e4SLinus Torvalds 11231da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 11241da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 11251da177e4SLinus Torvalds return -1; 11261da177e4SLinus Torvalds } 1127f88f0bdfSAnton Ivanov 11286da2ec56SKees Cook irq_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11296da2ec56SKees Cook sizeof(struct io_thread_req *), 1130f88f0bdfSAnton Ivanov GFP_KERNEL 1131f88f0bdfSAnton Ivanov ); 1132f88f0bdfSAnton Ivanov irq_remainder = 0; 1133f88f0bdfSAnton Ivanov 1134f88f0bdfSAnton Ivanov if (irq_req_buffer == NULL) { 1135f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1136f88f0bdfSAnton Ivanov return -1; 1137f88f0bdfSAnton Ivanov } 11386da2ec56SKees Cook io_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11396da2ec56SKees Cook sizeof(struct io_thread_req *), 1140f88f0bdfSAnton Ivanov GFP_KERNEL 1141f88f0bdfSAnton Ivanov ); 1142f88f0bdfSAnton Ivanov 1143f88f0bdfSAnton Ivanov io_remainder = 0; 1144f88f0bdfSAnton Ivanov 1145f88f0bdfSAnton Ivanov if (io_req_buffer == NULL) { 1146f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1147f88f0bdfSAnton Ivanov return -1; 1148f88f0bdfSAnton Ivanov } 11493ae5eaecSRussell King platform_driver_register(&ubd_driver); 1150b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1151f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1152f28169d2SJeff Dike err = ubd_add(i, &error); 1153f28169d2SJeff Dike if(err) 1154f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1155f28169d2SJeff Dike "%s\n", i, error); 1156f28169d2SJeff Dike } 1157b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 11581da177e4SLinus Torvalds return 0; 11591da177e4SLinus Torvalds } 11601da177e4SLinus Torvalds 11611da177e4SLinus Torvalds late_initcall(ubd_init); 11621da177e4SLinus Torvalds 1163d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 116491acb21fSJeff Dike unsigned long stack; 116591acb21fSJeff Dike int err; 116691acb21fSJeff Dike 116791acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 116891acb21fSJeff Dike if(global_openflags.s){ 116991acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 117091acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 117191acb21fSJeff Dike * enough. So use anyway the io thread. */ 117291acb21fSJeff Dike } 117391acb21fSJeff Dike stack = alloc_stack(0, 0); 117491acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 117591acb21fSJeff Dike &thread_fd); 117691acb21fSJeff Dike if(io_pid < 0){ 117791acb21fSJeff Dike printk(KERN_ERR 117891acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 117991acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 118091acb21fSJeff Dike io_pid = -1; 1181dc764e50SJeff Dike return 0; 118291acb21fSJeff Dike } 118391acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 1184c0b79a90SYong Zhang 0, "ubd", ubd_devs); 118591acb21fSJeff Dike if(err != 0) 118691acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1187f4c57a78SJeff Dike return 0; 118891acb21fSJeff Dike } 118991acb21fSJeff Dike 119091acb21fSJeff Dike device_initcall(ubd_driver_init); 119191acb21fSJeff Dike 1192a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 11931da177e4SLinus Torvalds { 1194a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 11957d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 11961da177e4SLinus Torvalds int err = 0; 11971da177e4SLinus Torvalds 11989a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 11997d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 12007d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 12011da177e4SLinus Torvalds if(err){ 12021da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 12037d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 12041da177e4SLinus Torvalds goto out; 12051da177e4SLinus Torvalds } 12061da177e4SLinus Torvalds } 12077d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 12087d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 12092c49be99SPaolo 'Blaisorblade' Giarrusso 12102c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 12112c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1212a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 12135f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 12141da177e4SLinus Torvalds err = -EROFS; 12152c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 12161da177e4SLinus Torvalds out: 12179a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 1218dc764e50SJeff Dike return err; 12191da177e4SLinus Torvalds } 12201da177e4SLinus Torvalds 1221db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode) 12221da177e4SLinus Torvalds { 12237d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12241da177e4SLinus Torvalds 12259a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12267d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 12275f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 12289a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 12291da177e4SLinus Torvalds } 12301da177e4SLinus Torvalds 123191acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 123291acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 123391acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 123491acb21fSJeff Dike __u64 bitmap_len) 12351da177e4SLinus Torvalds { 1236a43c8316SAnton Ivanov __u64 sector = io_offset >> SECTOR_SHIFT; 123791acb21fSJeff Dike int i, update_bitmap = 0; 12381da177e4SLinus Torvalds 1239a43c8316SAnton Ivanov for (i = 0; i < length >> SECTOR_SHIFT; i++) { 124091acb21fSJeff Dike if(cow_mask != NULL) 124191acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 124291acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 124309ace81cSJeff Dike continue; 12441da177e4SLinus Torvalds 124591acb21fSJeff Dike update_bitmap = 1; 124691acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 12471da177e4SLinus Torvalds } 124891acb21fSJeff Dike 124991acb21fSJeff Dike if(!update_bitmap) 125091acb21fSJeff Dike return; 125191acb21fSJeff Dike 125291acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 125391acb21fSJeff Dike 125491acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 125591acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 125691acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 125791acb21fSJeff Dike * for the original diagnosis. 125891acb21fSJeff Dike */ 12596d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 12606d074242SJiri Olsa sizeof(unsigned long)) - 1)) 126191acb21fSJeff Dike (*cow_offset)--; 126291acb21fSJeff Dike 126391acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 126491acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 126591acb21fSJeff Dike 126691acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 126791acb21fSJeff Dike *cow_offset += bitmap_offset; 126891acb21fSJeff Dike } 126991acb21fSJeff Dike 127091acb21fSJeff Dike static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, 127191acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 127291acb21fSJeff Dike { 1273a43c8316SAnton Ivanov __u64 sector = req->offset >> SECTOR_SHIFT; 127491acb21fSJeff Dike int i; 127591acb21fSJeff Dike 1276a43c8316SAnton Ivanov if (req->length > (sizeof(req->sector_mask) * 8) << SECTOR_SHIFT) 127791acb21fSJeff Dike panic("Operation too long"); 127891acb21fSJeff Dike 1279a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_READ) { 1280a43c8316SAnton Ivanov for (i = 0; i < req->length >> SECTOR_SHIFT; i++) { 128191acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 128291acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 128391acb21fSJeff Dike &req->sector_mask); 128491acb21fSJeff Dike } 128591acb21fSJeff Dike } 128691acb21fSJeff Dike else cowify_bitmap(req->offset, req->length, &req->sector_mask, 128791acb21fSJeff Dike &req->cow_offset, bitmap, bitmap_offset, 128891acb21fSJeff Dike req->bitmap_words, bitmap_len); 12891da177e4SLinus Torvalds } 12901da177e4SLinus Torvalds 1291ecb0a83eSChristoph Hellwig static int ubd_queue_one_vec(struct blk_mq_hw_ctx *hctx, struct request *req, 1292ecb0a83eSChristoph Hellwig u64 off, struct bio_vec *bvec) 12931da177e4SLinus Torvalds { 1294ecb0a83eSChristoph Hellwig struct ubd *dev = hctx->queue->queuedata; 1295ecb0a83eSChristoph Hellwig struct io_thread_req *io_req; 1296ecb0a83eSChristoph Hellwig int ret; 1297ecb0a83eSChristoph Hellwig 1298ecb0a83eSChristoph Hellwig io_req = kmalloc(sizeof(struct io_thread_req), GFP_ATOMIC); 1299ecb0a83eSChristoph Hellwig if (!io_req) 1300ecb0a83eSChristoph Hellwig return -ENOMEM; 130191acb21fSJeff Dike 130262f96cb0SJeff Dike io_req->req = req; 1303ecb0a83eSChristoph Hellwig if (dev->cow.file) 1304ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->cow.fd; 1305ecb0a83eSChristoph Hellwig else 1306ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->fd; 13070033dfd9SAnton Ivanov io_req->error = 0; 1308ecb0a83eSChristoph Hellwig 130953766defSAnton Ivanov if (bvec != NULL) { 131053766defSAnton Ivanov io_req->buffer = page_address(bvec->bv_page) + bvec->bv_offset; 131153766defSAnton Ivanov io_req->length = bvec->bv_len; 131253766defSAnton Ivanov } else { 131353766defSAnton Ivanov io_req->buffer = NULL; 131453766defSAnton Ivanov io_req->length = blk_rq_bytes(req); 131553766defSAnton Ivanov } 131653766defSAnton Ivanov 131753766defSAnton Ivanov io_req->sectorsize = SECTOR_SIZE; 1318ecb0a83eSChristoph Hellwig io_req->fds[1] = dev->fd; 131991acb21fSJeff Dike io_req->cow_offset = -1; 1320ecb0a83eSChristoph Hellwig io_req->offset = off; 132191acb21fSJeff Dike io_req->sector_mask = 0; 13221da177e4SLinus Torvalds io_req->offsets[0] = 0; 1323ecb0a83eSChristoph Hellwig io_req->offsets[1] = dev->cow.data_offset; 13241da177e4SLinus Torvalds 132553766defSAnton Ivanov if (dev->cow.file) 1326ecb0a83eSChristoph Hellwig cowify_req(io_req, dev->cow.bitmap, 1327ecb0a83eSChristoph Hellwig dev->cow.bitmap_offset, dev->cow.bitmap_len); 13281da177e4SLinus Torvalds 1329ecb0a83eSChristoph Hellwig ret = os_write_file(thread_fd, &io_req, sizeof(io_req)); 1330ecb0a83eSChristoph Hellwig if (ret != sizeof(io_req)) { 1331ecb0a83eSChristoph Hellwig if (ret != -EAGAIN) 1332ecb0a83eSChristoph Hellwig pr_err("write to io thread failed: %d\n", -ret); 1333bc1d72e7SRichard Weinberger kfree(io_req); 1334bc1d72e7SRichard Weinberger } 1335ecb0a83eSChristoph Hellwig return ret; 1336bc1d72e7SRichard Weinberger } 1337bc1d72e7SRichard Weinberger 133853766defSAnton Ivanov static int queue_rw_req(struct blk_mq_hw_ctx *hctx, struct request *req) 133953766defSAnton Ivanov { 134053766defSAnton Ivanov struct req_iterator iter; 134153766defSAnton Ivanov struct bio_vec bvec; 134253766defSAnton Ivanov int ret; 134353766defSAnton Ivanov u64 off = (u64)blk_rq_pos(req) << SECTOR_SHIFT; 134453766defSAnton Ivanov 134553766defSAnton Ivanov rq_for_each_segment(bvec, req, iter) { 134653766defSAnton Ivanov ret = ubd_queue_one_vec(hctx, req, off, &bvec); 134753766defSAnton Ivanov if (ret < 0) 134853766defSAnton Ivanov return ret; 134953766defSAnton Ivanov off += bvec.bv_len; 135053766defSAnton Ivanov } 135153766defSAnton Ivanov return 0; 135253766defSAnton Ivanov } 135353766defSAnton Ivanov 13544e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 13554e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd) 13561da177e4SLinus Torvalds { 13576961cd4dSJens Axboe struct ubd *ubd_dev = hctx->queue->queuedata; 13584e6da0feSRichard Weinberger struct request *req = bd->rq; 135953766defSAnton Ivanov int ret = 0, res = BLK_STS_OK; 13601da177e4SLinus Torvalds 13614e6da0feSRichard Weinberger blk_mq_start_request(req); 1362a0044bdfSJeff Dike 13636961cd4dSJens Axboe spin_lock_irq(&ubd_dev->lock); 13646961cd4dSJens Axboe 136553766defSAnton Ivanov switch (req_op(req)) { 136653766defSAnton Ivanov /* operations with no lentgth/offset arguments */ 136753766defSAnton Ivanov case REQ_OP_FLUSH: 1368ecb0a83eSChristoph Hellwig ret = ubd_queue_one_vec(hctx, req, 0, NULL); 136953766defSAnton Ivanov break; 137053766defSAnton Ivanov case REQ_OP_READ: 137153766defSAnton Ivanov case REQ_OP_WRITE: 137253766defSAnton Ivanov ret = queue_rw_req(hctx, req); 137353766defSAnton Ivanov break; 137453766defSAnton Ivanov default: 137553766defSAnton Ivanov WARN_ON_ONCE(1); 137653766defSAnton Ivanov res = BLK_STS_NOTSUPP; 137753766defSAnton Ivanov } 1378ecb0a83eSChristoph Hellwig 13796961cd4dSJens Axboe spin_unlock_irq(&ubd_dev->lock); 13806961cd4dSJens Axboe 13816961cd4dSJens Axboe if (ret < 0) 13824e6da0feSRichard Weinberger blk_mq_requeue_request(req, true); 13836961cd4dSJens Axboe 138453766defSAnton Ivanov return res; 138591acb21fSJeff Dike } 13864e6da0feSRichard Weinberger 1387a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1388a885c8c4SChristoph Hellwig { 13897d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1390a885c8c4SChristoph Hellwig 1391a885c8c4SChristoph Hellwig geo->heads = 128; 1392a885c8c4SChristoph Hellwig geo->sectors = 32; 13937d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1394a885c8c4SChristoph Hellwig return 0; 1395a885c8c4SChristoph Hellwig } 1396a885c8c4SChristoph Hellwig 1397a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 13981da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 13991da177e4SLinus Torvalds { 1400a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 140173855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 14021da177e4SLinus Torvalds 14031da177e4SLinus Torvalds switch (cmd) { 14041da177e4SLinus Torvalds struct cdrom_volctrl volume; 14051da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 140673855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 140773855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 140873855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 140973855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 14101da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 14111da177e4SLinus Torvalds sizeof(ubd_id))) 1412dc764e50SJeff Dike return -EFAULT; 1413dc764e50SJeff Dike return 0; 14141da177e4SLinus Torvalds 14151da177e4SLinus Torvalds case CDROMVOLREAD: 14161da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1417dc764e50SJeff Dike return -EFAULT; 14181da177e4SLinus Torvalds volume.channel0 = 255; 14191da177e4SLinus Torvalds volume.channel1 = 255; 14201da177e4SLinus Torvalds volume.channel2 = 255; 14211da177e4SLinus Torvalds volume.channel3 = 255; 14221da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1423dc764e50SJeff Dike return -EFAULT; 1424dc764e50SJeff Dike return 0; 14251da177e4SLinus Torvalds } 1426dc764e50SJeff Dike return -EINVAL; 14271da177e4SLinus Torvalds } 14281da177e4SLinus Torvalds 1429a43c8316SAnton Ivanov static int map_error(int error_code) 1430a43c8316SAnton Ivanov { 1431a43c8316SAnton Ivanov switch (error_code) { 1432a43c8316SAnton Ivanov case 0: 1433a43c8316SAnton Ivanov return BLK_STS_OK; 1434a43c8316SAnton Ivanov case ENOSYS: 1435a43c8316SAnton Ivanov case EOPNOTSUPP: 1436a43c8316SAnton Ivanov return BLK_STS_NOTSUPP; 1437a43c8316SAnton Ivanov case ENOSPC: 1438a43c8316SAnton Ivanov return BLK_STS_NOSPC; 1439a43c8316SAnton Ivanov } 1440a43c8316SAnton Ivanov return BLK_STS_IOERR; 1441a43c8316SAnton Ivanov } 1442a43c8316SAnton Ivanov 144391acb21fSJeff Dike static int update_bitmap(struct io_thread_req *req) 14441da177e4SLinus Torvalds { 144591acb21fSJeff Dike int n; 144691acb21fSJeff Dike 144791acb21fSJeff Dike if(req->cow_offset == -1) 1448a43c8316SAnton Ivanov return map_error(0); 144991acb21fSJeff Dike 14508c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[1], &req->bitmap_words, 14518c6157b6SAnton Ivanov sizeof(req->bitmap_words), req->cow_offset); 145291acb21fSJeff Dike if(n != sizeof(req->bitmap_words)){ 145391acb21fSJeff Dike printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, 145491acb21fSJeff Dike req->fds[1]); 1455a43c8316SAnton Ivanov return map_error(-n); 145691acb21fSJeff Dike } 145791acb21fSJeff Dike 1458a43c8316SAnton Ivanov return map_error(0); 145991acb21fSJeff Dike } 146091acb21fSJeff Dike 14615dc62b1bSWANG Cong static void do_io(struct io_thread_req *req) 146291acb21fSJeff Dike { 14631da177e4SLinus Torvalds char *buf; 146491acb21fSJeff Dike unsigned long len; 146591acb21fSJeff Dike int n, nsectors, start, end, bit; 14661da177e4SLinus Torvalds __u64 off; 14671da177e4SLinus Torvalds 1468a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_FLUSH) { 1469805f11a0SRichard Weinberger /* fds[0] is always either the rw image or our cow file */ 1470805f11a0SRichard Weinberger n = os_sync_file(req->fds[0]); 1471805f11a0SRichard Weinberger if (n != 0) { 1472805f11a0SRichard Weinberger printk("do_io - sync failed err = %d " 1473805f11a0SRichard Weinberger "fd = %d\n", -n, req->fds[0]); 1474a43c8316SAnton Ivanov req->error = map_error(-n); 1475805f11a0SRichard Weinberger } 1476805f11a0SRichard Weinberger return; 1477805f11a0SRichard Weinberger } 1478805f11a0SRichard Weinberger 14791da177e4SLinus Torvalds nsectors = req->length / req->sectorsize; 14801da177e4SLinus Torvalds start = 0; 14811da177e4SLinus Torvalds do { 148291acb21fSJeff Dike bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); 14831da177e4SLinus Torvalds end = start; 14841da177e4SLinus Torvalds while((end < nsectors) && 148591acb21fSJeff Dike (ubd_test_bit(end, (unsigned char *) 148691acb21fSJeff Dike &req->sector_mask) == bit)) 14871da177e4SLinus Torvalds end++; 14881da177e4SLinus Torvalds 148991acb21fSJeff Dike off = req->offset + req->offsets[bit] + 14901da177e4SLinus Torvalds start * req->sectorsize; 14911da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 14921da177e4SLinus Torvalds buf = &req->buffer[start * req->sectorsize]; 14931da177e4SLinus Torvalds 1494a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_READ) { 149591acb21fSJeff Dike n = 0; 149691acb21fSJeff Dike do { 149791acb21fSJeff Dike buf = &buf[n]; 149891acb21fSJeff Dike len -= n; 14998c6157b6SAnton Ivanov n = os_pread_file(req->fds[bit], buf, len, off); 150091acb21fSJeff Dike if (n < 0) { 150191acb21fSJeff Dike printk("do_io - read failed, err = %d " 150291acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 1503a43c8316SAnton Ivanov req->error = map_error(-n); 15041da177e4SLinus Torvalds return; 15051da177e4SLinus Torvalds } 150691acb21fSJeff Dike } while((n < len) && (n != 0)); 150791acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 150891acb21fSJeff Dike } else { 15098c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[bit], buf, len, off); 151091acb21fSJeff Dike if(n != len){ 151191acb21fSJeff Dike printk("do_io - write failed err = %d " 151291acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 1513a43c8316SAnton Ivanov req->error = map_error(-n); 151491acb21fSJeff Dike return; 151591acb21fSJeff Dike } 151691acb21fSJeff Dike } 15171da177e4SLinus Torvalds 15181da177e4SLinus Torvalds start = end; 15191da177e4SLinus Torvalds } while(start < nsectors); 152091acb21fSJeff Dike 152191acb21fSJeff Dike req->error = update_bitmap(req); 15221da177e4SLinus Torvalds } 152391acb21fSJeff Dike 152491acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 152591acb21fSJeff Dike * from ubd_init, which is an initcall. 152691acb21fSJeff Dike */ 152791acb21fSJeff Dike int kernel_fd = -1; 152891acb21fSJeff Dike 1529d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1530d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 153191acb21fSJeff Dike 153291acb21fSJeff Dike int io_thread(void *arg) 153391acb21fSJeff Dike { 1534f88f0bdfSAnton Ivanov int n, count, written, res; 153591acb21fSJeff Dike 153691d44ff8SRichard Weinberger os_fix_helper_signals(); 153791d44ff8SRichard Weinberger 153891acb21fSJeff Dike while(1){ 1539f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 1540f88f0bdfSAnton Ivanov kernel_fd, 1541f88f0bdfSAnton Ivanov io_req_buffer, 1542f88f0bdfSAnton Ivanov &io_remainder, 1543f88f0bdfSAnton Ivanov &io_remainder_size, 1544f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 1545f88f0bdfSAnton Ivanov ); 1546f88f0bdfSAnton Ivanov if (n < 0) { 1547f88f0bdfSAnton Ivanov if (n == -EAGAIN) { 1548f88f0bdfSAnton Ivanov ubd_read_poll(-1); 1549f88f0bdfSAnton Ivanov continue; 1550f88f0bdfSAnton Ivanov } else { 1551f88f0bdfSAnton Ivanov printk("io_thread - read failed, fd = %d, " 1552f88f0bdfSAnton Ivanov "err = %d," 1553f88f0bdfSAnton Ivanov "reminder = %d\n", 1554f88f0bdfSAnton Ivanov kernel_fd, -n, io_remainder_size); 1555f88f0bdfSAnton Ivanov } 1556f88f0bdfSAnton Ivanov } 1557f88f0bdfSAnton Ivanov 1558f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 1559f88f0bdfSAnton Ivanov io_count++; 1560f88f0bdfSAnton Ivanov do_io((*io_req_buffer)[count]); 1561f88f0bdfSAnton Ivanov } 1562f88f0bdfSAnton Ivanov 1563f88f0bdfSAnton Ivanov written = 0; 1564f88f0bdfSAnton Ivanov 1565f88f0bdfSAnton Ivanov do { 1566f88f0bdfSAnton Ivanov res = os_write_file(kernel_fd, ((char *) io_req_buffer) + written, n); 1567ff6a1798SAnton Ivanov if (res >= 0) { 1568f88f0bdfSAnton Ivanov written += res; 1569f88f0bdfSAnton Ivanov } else { 1570f88f0bdfSAnton Ivanov if (res != -EAGAIN) { 1571ff6a1798SAnton Ivanov printk("io_thread - write failed, fd = %d, " 157291acb21fSJeff Dike "err = %d\n", kernel_fd, -n); 157391acb21fSJeff Dike } 157491acb21fSJeff Dike } 1575f88f0bdfSAnton Ivanov if (written < n) { 1576f88f0bdfSAnton Ivanov ubd_write_poll(-1); 1577f88f0bdfSAnton Ivanov } 1578f88f0bdfSAnton Ivanov } while (written < n); 157991acb21fSJeff Dike } 158091acb21fSJeff Dike 15811b57e9c2SJeff Dike return 0; 15821b57e9c2SJeff Dike } 1583