1dbddf429SAlex Dewar // SPDX-License-Identifier: GPL-2.0 21da177e4SLinus Torvalds /* 3a41421edSAnton Ivanov * Copyright (C) 2018 Cambridge Greys Ltd 4f88f0bdfSAnton Ivanov * Copyright (C) 2015-2016 Anton Ivanov (aivanov@brocade.com) 51da177e4SLinus Torvalds * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) 61da177e4SLinus Torvalds */ 71da177e4SLinus Torvalds 81da177e4SLinus Torvalds /* 2001-09-28...2002-04-17 91da177e4SLinus Torvalds * Partition stuff by James_McMechan@hotmail.com 101da177e4SLinus Torvalds * old style ubd by setting UBD_SHIFT to 0 111da177e4SLinus Torvalds * 2002-09-27...2002-10-18 massive tinkering for 2.5 121da177e4SLinus Torvalds * partitions have changed in 2.5 131da177e4SLinus Torvalds * 2003-01-29 more tinkering for 2.5.59-1 141da177e4SLinus Torvalds * This should now address the sysfs problems and has 151da177e4SLinus Torvalds * the symlink for devfs to allow for booting with 161da177e4SLinus Torvalds * the common /dev/ubd/discX/... names rather than 171da177e4SLinus Torvalds * only /dev/ubdN/discN this version also has lots of 181da177e4SLinus Torvalds * clean ups preparing for ubd-many. 191da177e4SLinus Torvalds * James McMechan 201da177e4SLinus Torvalds */ 211da177e4SLinus Torvalds 221da177e4SLinus Torvalds #define UBD_SHIFT 4 231da177e4SLinus Torvalds 248ea3c06aSAl Viro #include <linux/module.h> 258ea3c06aSAl Viro #include <linux/init.h> 268ea3c06aSAl Viro #include <linux/blkdev.h> 274e6da0feSRichard Weinberger #include <linux/blk-mq.h> 288ea3c06aSAl Viro #include <linux/ata.h> 298ea3c06aSAl Viro #include <linux/hdreg.h> 308ea3c06aSAl Viro #include <linux/cdrom.h> 318ea3c06aSAl Viro #include <linux/proc_fs.h> 328ea3c06aSAl Viro #include <linux/seq_file.h> 338ea3c06aSAl Viro #include <linux/ctype.h> 348ea3c06aSAl Viro #include <linux/slab.h> 358ea3c06aSAl Viro #include <linux/vmalloc.h> 368ea3c06aSAl Viro #include <linux/platform_device.h> 378ea3c06aSAl Viro #include <linux/scatterlist.h> 388ea3c06aSAl Viro #include <asm/tlbflush.h> 3937185b33SAl Viro #include <kern_util.h> 401da177e4SLinus Torvalds #include "mconsole_kern.h" 4137185b33SAl Viro #include <init.h> 4237185b33SAl Viro #include <irq_kern.h> 438ea3c06aSAl Viro #include "ubd.h" 4437185b33SAl Viro #include <os.h> 451da177e4SLinus Torvalds #include "cow.h" 461da177e4SLinus Torvalds 47a43c8316SAnton Ivanov /* Max request size is determined by sector mask - 32K */ 48a43c8316SAnton Ivanov #define UBD_MAX_REQUEST (8 * sizeof(long)) 491da177e4SLinus Torvalds 501da177e4SLinus Torvalds struct io_thread_req { 5162f96cb0SJeff Dike struct request *req; 521da177e4SLinus Torvalds int fds[2]; 531da177e4SLinus Torvalds unsigned long offsets[2]; 541da177e4SLinus Torvalds unsigned long long offset; 551da177e4SLinus Torvalds unsigned long length; 561da177e4SLinus Torvalds char *buffer; 571da177e4SLinus Torvalds int sectorsize; 5891acb21fSJeff Dike unsigned long sector_mask; 5991acb21fSJeff Dike unsigned long long cow_offset; 6091acb21fSJeff Dike unsigned long bitmap_words[2]; 611da177e4SLinus Torvalds int error; 621da177e4SLinus Torvalds }; 631da177e4SLinus Torvalds 64f88f0bdfSAnton Ivanov 65f88f0bdfSAnton Ivanov static struct io_thread_req * (*irq_req_buffer)[]; 66f88f0bdfSAnton Ivanov static struct io_thread_req *irq_remainder; 67f88f0bdfSAnton Ivanov static int irq_remainder_size; 68f88f0bdfSAnton Ivanov 69f88f0bdfSAnton Ivanov static struct io_thread_req * (*io_req_buffer)[]; 70f88f0bdfSAnton Ivanov static struct io_thread_req *io_remainder; 71f88f0bdfSAnton Ivanov static int io_remainder_size; 72f88f0bdfSAnton Ivanov 73f88f0bdfSAnton Ivanov 74f88f0bdfSAnton Ivanov 7591acb21fSJeff Dike static inline int ubd_test_bit(__u64 bit, unsigned char *data) 761da177e4SLinus Torvalds { 771da177e4SLinus Torvalds __u64 n; 781da177e4SLinus Torvalds int bits, off; 791da177e4SLinus Torvalds 8091acb21fSJeff Dike bits = sizeof(data[0]) * 8; 811da177e4SLinus Torvalds n = bit / bits; 821da177e4SLinus Torvalds off = bit % bits; 83dc764e50SJeff Dike return (data[n] & (1 << off)) != 0; 841da177e4SLinus Torvalds } 851da177e4SLinus Torvalds 8691acb21fSJeff Dike static inline void ubd_set_bit(__u64 bit, unsigned char *data) 871da177e4SLinus Torvalds { 881da177e4SLinus Torvalds __u64 n; 891da177e4SLinus Torvalds int bits, off; 901da177e4SLinus Torvalds 9191acb21fSJeff Dike bits = sizeof(data[0]) * 8; 921da177e4SLinus Torvalds n = bit / bits; 931da177e4SLinus Torvalds off = bit % bits; 9491acb21fSJeff Dike data[n] |= (1 << off); 951da177e4SLinus Torvalds } 961da177e4SLinus Torvalds /*End stuff from ubd_user.h*/ 971da177e4SLinus Torvalds 981da177e4SLinus Torvalds #define DRIVER_NAME "uml-blkdev" 991da177e4SLinus Torvalds 100d7fb2c38SPaolo 'Blaisorblade' Giarrusso static DEFINE_MUTEX(ubd_lock); 1019a181c58SArnd Bergmann static DEFINE_MUTEX(ubd_mutex); /* replaces BKL, might not be needed */ 1021da177e4SLinus Torvalds 103a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode); 104db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode); 105a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 1061da177e4SLinus Torvalds unsigned int cmd, unsigned long arg); 107a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); 1081da177e4SLinus Torvalds 10997d88ac8SPaolo 'Blaisorblade' Giarrusso #define MAX_DEV (16) 1101da177e4SLinus Torvalds 11183d5cde4SAlexey Dobriyan static const struct block_device_operations ubd_blops = { 1121da177e4SLinus Torvalds .owner = THIS_MODULE, 113a625c998SAl Viro .open = ubd_open, 114a625c998SAl Viro .release = ubd_release, 115a625c998SAl Viro .ioctl = ubd_ioctl, 116ab0cf1e4SArnd Bergmann .compat_ioctl = blkdev_compat_ptr_ioctl, 117a885c8c4SChristoph Hellwig .getgeo = ubd_getgeo, 1181da177e4SLinus Torvalds }; 1191da177e4SLinus Torvalds 1201da177e4SLinus Torvalds /* Protected by ubd_lock */ 121792dd4fcSChristoph Hellwig static int fake_major = UBD_MAJOR; 1221da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1231da177e4SLinus Torvalds static struct gendisk *fake_gendisk[MAX_DEV]; 1241da177e4SLinus Torvalds 1251da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1261da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1271da177e4SLinus Torvalds .cl = 1 }) 1281da177e4SLinus Torvalds #else 1291da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1301da177e4SLinus Torvalds .cl = 1 }) 1311da177e4SLinus Torvalds #endif 1321da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1331da177e4SLinus Torvalds 1341da177e4SLinus Torvalds struct cow { 1352a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file name */ 1361da177e4SLinus Torvalds char *file; 1372a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file fd */ 1381da177e4SLinus Torvalds int fd; 1391da177e4SLinus Torvalds unsigned long *bitmap; 1401da177e4SLinus Torvalds unsigned long bitmap_len; 1411da177e4SLinus Torvalds int bitmap_offset; 1421da177e4SLinus Torvalds int data_offset; 1431da177e4SLinus Torvalds }; 1441da177e4SLinus Torvalds 145a0044bdfSJeff Dike #define MAX_SG 64 146a0044bdfSJeff Dike 1471da177e4SLinus Torvalds struct ubd { 1482a9d32f6SPaolo 'Blaisorblade' Giarrusso /* name (and fd, below) of the file opened for writing, either the 1492a9d32f6SPaolo 'Blaisorblade' Giarrusso * backing or the cow file. */ 1501da177e4SLinus Torvalds char *file; 1511da177e4SLinus Torvalds int count; 1521da177e4SLinus Torvalds int fd; 1531da177e4SLinus Torvalds __u64 size; 1541da177e4SLinus Torvalds struct openflags boot_openflags; 1551da177e4SLinus Torvalds struct openflags openflags; 15684e945e3SPaolo 'Blaisorblade' Giarrusso unsigned shared:1; 15784e945e3SPaolo 'Blaisorblade' Giarrusso unsigned no_cow:1; 15850109b5aSAnton Ivanov unsigned no_trim:1; 1591da177e4SLinus Torvalds struct cow cow; 1601da177e4SLinus Torvalds struct platform_device pdev; 16162f96cb0SJeff Dike struct request_queue *queue; 1624e6da0feSRichard Weinberger struct blk_mq_tag_set tag_set; 16362f96cb0SJeff Dike spinlock_t lock; 1644e6da0feSRichard Weinberger }; 1654e6da0feSRichard Weinberger 1661da177e4SLinus Torvalds #define DEFAULT_COW { \ 1671da177e4SLinus Torvalds .file = NULL, \ 1681da177e4SLinus Torvalds .fd = -1, \ 1691da177e4SLinus Torvalds .bitmap = NULL, \ 1701da177e4SLinus Torvalds .bitmap_offset = 0, \ 1711da177e4SLinus Torvalds .data_offset = 0, \ 1721da177e4SLinus Torvalds } 1731da177e4SLinus Torvalds 1741da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1751da177e4SLinus Torvalds .file = NULL, \ 1761da177e4SLinus Torvalds .count = 0, \ 1771da177e4SLinus Torvalds .fd = -1, \ 1781da177e4SLinus Torvalds .size = -1, \ 1791da177e4SLinus Torvalds .boot_openflags = OPEN_FLAGS, \ 1801da177e4SLinus Torvalds .openflags = OPEN_FLAGS, \ 1811da177e4SLinus Torvalds .no_cow = 0, \ 18250109b5aSAnton Ivanov .no_trim = 0, \ 1836c29256cSJeff Dike .shared = 0, \ 1841da177e4SLinus Torvalds .cow = DEFAULT_COW, \ 18522e65004SThomas Gleixner .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \ 1861da177e4SLinus Torvalds } 1871da177e4SLinus Torvalds 188b8831a1dSJeff Dike /* Protected by ubd_lock */ 1895dc62b1bSWANG Cong static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; 1901da177e4SLinus Torvalds 1911da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 1921da177e4SLinus Torvalds static int fake_ide = 0; 1931da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 1941da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 1951da177e4SLinus Torvalds 1964e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 1974e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd); 1984e6da0feSRichard Weinberger 1991da177e4SLinus Torvalds static void make_proc_ide(void) 2001da177e4SLinus Torvalds { 2011da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 2021da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 2031da177e4SLinus Torvalds } 2041da177e4SLinus Torvalds 2056613c5e8SAlexey Dobriyan static int fake_ide_media_proc_show(struct seq_file *m, void *v) 2061da177e4SLinus Torvalds { 2076613c5e8SAlexey Dobriyan seq_puts(m, "disk\n"); 2086613c5e8SAlexey Dobriyan return 0; 2096613c5e8SAlexey Dobriyan } 2101da177e4SLinus Torvalds 211c0a9290eSWANG Cong static void make_ide_entries(const char *dev_name) 2121da177e4SLinus Torvalds { 2131da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2141da177e4SLinus Torvalds char name[64]; 2151da177e4SLinus Torvalds 2161da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2171da177e4SLinus Torvalds 2181da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2191da177e4SLinus Torvalds if(!dir) return; 2201da177e4SLinus Torvalds 2213f3942acSChristoph Hellwig ent = proc_create_single("media", S_IRUGO, dir, 2223f3942acSChristoph Hellwig fake_ide_media_proc_show); 2231da177e4SLinus Torvalds if(!ent) return; 224c0a9290eSWANG Cong snprintf(name, sizeof(name), "ide0/%s", dev_name); 2251da177e4SLinus Torvalds proc_symlink(dev_name, proc_ide_root, name); 2261da177e4SLinus Torvalds } 2271da177e4SLinus Torvalds 2281da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2291da177e4SLinus Torvalds { 2301da177e4SLinus Torvalds fake_ide = 1; 231dc764e50SJeff Dike return 1; 2321da177e4SLinus Torvalds } 2331da177e4SLinus Torvalds 2341da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2351da177e4SLinus Torvalds 2361da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2371da177e4SLinus Torvalds "fake_ide\n" 2381da177e4SLinus Torvalds " Create ide0 entries that map onto ubd devices.\n\n" 2391da177e4SLinus Torvalds ); 2401da177e4SLinus Torvalds 2411da177e4SLinus Torvalds static int parse_unit(char **ptr) 2421da177e4SLinus Torvalds { 2431da177e4SLinus Torvalds char *str = *ptr, *end; 2441da177e4SLinus Torvalds int n = -1; 2451da177e4SLinus Torvalds 2461da177e4SLinus Torvalds if(isdigit(*str)) { 2471da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2481da177e4SLinus Torvalds if(end == str) 249dc764e50SJeff Dike return -1; 2501da177e4SLinus Torvalds *ptr = end; 2511da177e4SLinus Torvalds } 25297d88ac8SPaolo 'Blaisorblade' Giarrusso else if (('a' <= *str) && (*str <= 'z')) { 2531da177e4SLinus Torvalds n = *str - 'a'; 2541da177e4SLinus Torvalds str++; 2551da177e4SLinus Torvalds *ptr = str; 2561da177e4SLinus Torvalds } 257dc764e50SJeff Dike return n; 2581da177e4SLinus Torvalds } 2591da177e4SLinus Torvalds 260d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* If *index_out == -1 at exit, the passed option was a general one; 261d8d7c28eSPaolo 'Blaisorblade' Giarrusso * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it 262d8d7c28eSPaolo 'Blaisorblade' Giarrusso * should not be freed on exit. 263d8d7c28eSPaolo 'Blaisorblade' Giarrusso */ 264f28169d2SJeff Dike static int ubd_setup_common(char *str, int *index_out, char **error_out) 2651da177e4SLinus Torvalds { 2667d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 2671da177e4SLinus Torvalds struct openflags flags = global_openflags; 2681da177e4SLinus Torvalds char *backing_file; 269b8831a1dSJeff Dike int n, err = 0, i; 2701da177e4SLinus Torvalds 2711da177e4SLinus Torvalds if(index_out) *index_out = -1; 2721da177e4SLinus Torvalds n = *str; 2731da177e4SLinus Torvalds if(n == '='){ 2741da177e4SLinus Torvalds char *end; 2751da177e4SLinus Torvalds int major; 2761da177e4SLinus Torvalds 2771da177e4SLinus Torvalds str++; 2781da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 2791da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 2809ca55299SDaniel Walter return err; 2811da177e4SLinus Torvalds } 2821da177e4SLinus Torvalds 283f28169d2SJeff Dike err = -EINVAL; 284b8831a1dSJeff Dike major = simple_strtoul(str, &end, 0); 285b8831a1dSJeff Dike if((*end != '\0') || (end == str)){ 286b8831a1dSJeff Dike *error_out = "Didn't parse major number"; 2879ca55299SDaniel Walter return err; 288b8831a1dSJeff Dike } 289b8831a1dSJeff Dike 290d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 291792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 292f28169d2SJeff Dike *error_out = "Can't assign a fake major twice"; 2931da177e4SLinus Torvalds goto out1; 2941da177e4SLinus Torvalds } 2951da177e4SLinus Torvalds 2961da177e4SLinus Torvalds fake_major = major; 2971da177e4SLinus Torvalds 2981da177e4SLinus Torvalds printk(KERN_INFO "Setting extra ubd major number to %d\n", 2991da177e4SLinus Torvalds major); 3001da177e4SLinus Torvalds err = 0; 3011da177e4SLinus Torvalds out1: 302d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 303f28169d2SJeff Dike return err; 3041da177e4SLinus Torvalds } 3051da177e4SLinus Torvalds 3061da177e4SLinus Torvalds n = parse_unit(&str); 3071da177e4SLinus Torvalds if(n < 0){ 308f28169d2SJeff Dike *error_out = "Couldn't parse device number"; 309f28169d2SJeff Dike return -EINVAL; 3101da177e4SLinus Torvalds } 3111da177e4SLinus Torvalds if(n >= MAX_DEV){ 312f28169d2SJeff Dike *error_out = "Device number out of range"; 313f28169d2SJeff Dike return 1; 3141da177e4SLinus Torvalds } 3151da177e4SLinus Torvalds 316f28169d2SJeff Dike err = -EBUSY; 317d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 3181da177e4SLinus Torvalds 3197d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 3207d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file != NULL){ 321f28169d2SJeff Dike *error_out = "Device is already configured"; 3221da177e4SLinus Torvalds goto out; 3231da177e4SLinus Torvalds } 3241da177e4SLinus Torvalds 3251da177e4SLinus Torvalds if (index_out) 3261da177e4SLinus Torvalds *index_out = n; 3271da177e4SLinus Torvalds 328f28169d2SJeff Dike err = -EINVAL; 32950109b5aSAnton Ivanov for (i = 0; i < sizeof("rscdt="); i++) { 3301da177e4SLinus Torvalds switch (*str) { 3311da177e4SLinus Torvalds case 'r': 3321da177e4SLinus Torvalds flags.w = 0; 3331da177e4SLinus Torvalds break; 3341da177e4SLinus Torvalds case 's': 3351da177e4SLinus Torvalds flags.s = 1; 3361da177e4SLinus Torvalds break; 3371da177e4SLinus Torvalds case 'd': 3387d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->no_cow = 1; 3391da177e4SLinus Torvalds break; 3406c29256cSJeff Dike case 'c': 3417d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->shared = 1; 3426c29256cSJeff Dike break; 34350109b5aSAnton Ivanov case 't': 34450109b5aSAnton Ivanov ubd_dev->no_trim = 1; 34550109b5aSAnton Ivanov break; 3461da177e4SLinus Torvalds case '=': 3471da177e4SLinus Torvalds str++; 3481da177e4SLinus Torvalds goto break_loop; 3491da177e4SLinus Torvalds default: 350f28169d2SJeff Dike *error_out = "Expected '=' or flag letter " 35150109b5aSAnton Ivanov "(r, s, c, t or d)"; 3521da177e4SLinus Torvalds goto out; 3531da177e4SLinus Torvalds } 3541da177e4SLinus Torvalds str++; 3551da177e4SLinus Torvalds } 3561da177e4SLinus Torvalds 3571da177e4SLinus Torvalds if (*str == '=') 358f28169d2SJeff Dike *error_out = "Too many flags specified"; 3591da177e4SLinus Torvalds else 360f28169d2SJeff Dike *error_out = "Missing '='"; 3611da177e4SLinus Torvalds goto out; 3621da177e4SLinus Torvalds 3631da177e4SLinus Torvalds break_loop: 3641da177e4SLinus Torvalds backing_file = strchr(str, ','); 3651da177e4SLinus Torvalds 366f28169d2SJeff Dike if (backing_file == NULL) 3671da177e4SLinus Torvalds backing_file = strchr(str, ':'); 3681da177e4SLinus Torvalds 369f28169d2SJeff Dike if(backing_file != NULL){ 370f28169d2SJeff Dike if(ubd_dev->no_cow){ 371f28169d2SJeff Dike *error_out = "Can't specify both 'd' and a cow file"; 372f28169d2SJeff Dike goto out; 373f28169d2SJeff Dike } 3741da177e4SLinus Torvalds else { 3751da177e4SLinus Torvalds *backing_file = '\0'; 3761da177e4SLinus Torvalds backing_file++; 3771da177e4SLinus Torvalds } 3781da177e4SLinus Torvalds } 379f28169d2SJeff Dike err = 0; 3807d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->file = str; 3817d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.file = backing_file; 3827d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->boot_openflags = flags; 3831da177e4SLinus Torvalds out: 384d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 385f28169d2SJeff Dike return err; 3861da177e4SLinus Torvalds } 3871da177e4SLinus Torvalds 3881da177e4SLinus Torvalds static int ubd_setup(char *str) 3891da177e4SLinus Torvalds { 390f28169d2SJeff Dike char *error; 391f28169d2SJeff Dike int err; 392f28169d2SJeff Dike 393f28169d2SJeff Dike err = ubd_setup_common(str, NULL, &error); 394f28169d2SJeff Dike if(err) 395f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize device with \"%s\" : " 396f28169d2SJeff Dike "%s\n", str, error); 397f28169d2SJeff Dike return 1; 3981da177e4SLinus Torvalds } 3991da177e4SLinus Torvalds 4001da177e4SLinus Torvalds __setup("ubd", ubd_setup); 4011da177e4SLinus Torvalds __uml_help(ubd_setup, 4021da177e4SLinus Torvalds "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" 4031da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 4041da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 4051da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 4061da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 4071da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 4081da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 409f28169d2SJeff Dike " When using only one filename, UML will detect whether to treat it like\n" 4101da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 4111da177e4SLinus Torvalds " flag:\n" 4121da177e4SLinus Torvalds " ubd0d=BackingFile\n" 4131da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 4141da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 4151da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 4161da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 4171da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 4181da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 4191da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 42020ede453SJeff Dike " an 's' will cause data to be written to disk on the host immediately.\n" 42120ede453SJeff Dike " 'c' will cause the device to be treated as being shared between multiple\n" 42220ede453SJeff Dike " UMLs and file locking will be turned off - this is appropriate for a\n" 42320ede453SJeff Dike " cluster filesystem and inappropriate at almost all other times.\n\n" 42450109b5aSAnton Ivanov " 't' will disable trim/discard support on the device (enabled by default).\n\n" 4251da177e4SLinus Torvalds ); 4261da177e4SLinus Torvalds 4278299ca5cSJeff Dike static int udb_setup(char *str) 4281da177e4SLinus Torvalds { 4291da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 4301da177e4SLinus Torvalds "udb TYPO\n", str); 431dc764e50SJeff Dike return 1; 4321da177e4SLinus Torvalds } 4331da177e4SLinus Torvalds 4341da177e4SLinus Torvalds __setup("udb", udb_setup); 4351da177e4SLinus Torvalds __uml_help(udb_setup, 4361da177e4SLinus Torvalds "udb\n" 4370894e27eSJeff Dike " This option is here solely to catch ubd -> udb typos, which can be\n" 4380894e27eSJeff Dike " to impossible to catch visually unless you specifically look for\n" 4390894e27eSJeff Dike " them. The only result of any option starting with 'udb' is an error\n" 4401da177e4SLinus Torvalds " in the boot output.\n\n" 4411da177e4SLinus Torvalds ); 4421da177e4SLinus Torvalds 44391acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 4445dc62b1bSWANG Cong static int thread_fd = -1; 44509ace81cSJeff Dike 446f88f0bdfSAnton Ivanov /* Function to read several request pointers at a time 447f88f0bdfSAnton Ivanov * handling fractional reads if (and as) needed 448f88f0bdfSAnton Ivanov */ 449f88f0bdfSAnton Ivanov 450f88f0bdfSAnton Ivanov static int bulk_req_safe_read( 451f88f0bdfSAnton Ivanov int fd, 452f88f0bdfSAnton Ivanov struct io_thread_req * (*request_buffer)[], 453f88f0bdfSAnton Ivanov struct io_thread_req **remainder, 454f88f0bdfSAnton Ivanov int *remainder_size, 455f88f0bdfSAnton Ivanov int max_recs 456f88f0bdfSAnton Ivanov ) 457f88f0bdfSAnton Ivanov { 458f88f0bdfSAnton Ivanov int n = 0; 459f88f0bdfSAnton Ivanov int res = 0; 460f88f0bdfSAnton Ivanov 461f88f0bdfSAnton Ivanov if (*remainder_size > 0) { 462f88f0bdfSAnton Ivanov memmove( 463f88f0bdfSAnton Ivanov (char *) request_buffer, 464f88f0bdfSAnton Ivanov (char *) remainder, *remainder_size 465f88f0bdfSAnton Ivanov ); 466f88f0bdfSAnton Ivanov n = *remainder_size; 467f88f0bdfSAnton Ivanov } 468f88f0bdfSAnton Ivanov 469f88f0bdfSAnton Ivanov res = os_read_file( 470f88f0bdfSAnton Ivanov fd, 471f88f0bdfSAnton Ivanov ((char *) request_buffer) + *remainder_size, 472f88f0bdfSAnton Ivanov sizeof(struct io_thread_req *)*max_recs 473f88f0bdfSAnton Ivanov - *remainder_size 474f88f0bdfSAnton Ivanov ); 475f88f0bdfSAnton Ivanov if (res > 0) { 476f88f0bdfSAnton Ivanov n += res; 477f88f0bdfSAnton Ivanov if ((n % sizeof(struct io_thread_req *)) > 0) { 478f88f0bdfSAnton Ivanov /* 479f88f0bdfSAnton Ivanov * Read somehow returned not a multiple of dword 480f88f0bdfSAnton Ivanov * theoretically possible, but never observed in the 481f88f0bdfSAnton Ivanov * wild, so read routine must be able to handle it 482f88f0bdfSAnton Ivanov */ 483f88f0bdfSAnton Ivanov *remainder_size = n % sizeof(struct io_thread_req *); 484f88f0bdfSAnton Ivanov WARN(*remainder_size > 0, "UBD IPC read returned a partial result"); 485f88f0bdfSAnton Ivanov memmove( 486f88f0bdfSAnton Ivanov remainder, 487f88f0bdfSAnton Ivanov ((char *) request_buffer) + 488f88f0bdfSAnton Ivanov (n/sizeof(struct io_thread_req *))*sizeof(struct io_thread_req *), 489f88f0bdfSAnton Ivanov *remainder_size 490f88f0bdfSAnton Ivanov ); 491f88f0bdfSAnton Ivanov n = n - *remainder_size; 492f88f0bdfSAnton Ivanov } 493f88f0bdfSAnton Ivanov } else { 494f88f0bdfSAnton Ivanov n = res; 495f88f0bdfSAnton Ivanov } 496f88f0bdfSAnton Ivanov return n; 497f88f0bdfSAnton Ivanov } 498f88f0bdfSAnton Ivanov 49962f96cb0SJeff Dike /* Called without dev->lock held, and only in interrupt context. */ 50091acb21fSJeff Dike static void ubd_handler(void) 50191acb21fSJeff Dike { 50291acb21fSJeff Dike int n; 503f88f0bdfSAnton Ivanov int count; 50409ace81cSJeff Dike 505a0044bdfSJeff Dike while(1){ 506f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 507f88f0bdfSAnton Ivanov thread_fd, 508f88f0bdfSAnton Ivanov irq_req_buffer, 509f88f0bdfSAnton Ivanov &irq_remainder, 510f88f0bdfSAnton Ivanov &irq_remainder_size, 511f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 512f88f0bdfSAnton Ivanov ); 513f88f0bdfSAnton Ivanov if (n < 0) { 514a0044bdfSJeff Dike if(n == -EAGAIN) 515a0044bdfSJeff Dike break; 516a0044bdfSJeff Dike printk(KERN_ERR "spurious interrupt in ubd_handler, " 517a0044bdfSJeff Dike "err = %d\n", -n); 51891acb21fSJeff Dike return; 51991acb21fSJeff Dike } 520f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 5214e6da0feSRichard Weinberger struct io_thread_req *io_req = (*irq_req_buffer)[count]; 522a0044bdfSJeff Dike 52350109b5aSAnton Ivanov if ((io_req->error == BLK_STS_NOTSUPP) && (req_op(io_req->req) == REQ_OP_DISCARD)) { 52450109b5aSAnton Ivanov blk_queue_max_discard_sectors(io_req->req->q, 0); 52550109b5aSAnton Ivanov blk_queue_max_write_zeroes_sectors(io_req->req->q, 0); 52650109b5aSAnton Ivanov blk_queue_flag_clear(QUEUE_FLAG_DISCARD, io_req->req->q); 52750109b5aSAnton Ivanov } 52850109b5aSAnton Ivanov if ((io_req->error) || (io_req->buffer == NULL)) 52950109b5aSAnton Ivanov blk_mq_end_request(io_req->req, io_req->error); 53050109b5aSAnton Ivanov else { 531a43c8316SAnton Ivanov if (!blk_update_request(io_req->req, io_req->error, io_req->length)) 532a43c8316SAnton Ivanov __blk_mq_end_request(io_req->req, io_req->error); 53350109b5aSAnton Ivanov } 5344e6da0feSRichard Weinberger kfree(io_req); 535a0044bdfSJeff Dike } 53691acb21fSJeff Dike } 5374e6da0feSRichard Weinberger } 5384e6da0feSRichard Weinberger 5397bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 5401da177e4SLinus Torvalds { 54191acb21fSJeff Dike ubd_handler(); 542dc764e50SJeff Dike return IRQ_HANDLED; 5431da177e4SLinus Torvalds } 5441da177e4SLinus Torvalds 54591acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 54691acb21fSJeff Dike static int io_pid = -1; 54791acb21fSJeff Dike 5485dc62b1bSWANG Cong static void kill_io_thread(void) 54991acb21fSJeff Dike { 55091acb21fSJeff Dike if(io_pid != -1) 55191acb21fSJeff Dike os_kill_process(io_pid, 1); 55291acb21fSJeff Dike } 55391acb21fSJeff Dike 55491acb21fSJeff Dike __uml_exitcall(kill_io_thread); 55591acb21fSJeff Dike 556d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5571da177e4SLinus Torvalds { 5581da177e4SLinus Torvalds char *file; 55985356398SRichard Weinberger int fd; 56085356398SRichard Weinberger int err; 5611da177e4SLinus Torvalds 56285356398SRichard Weinberger __u32 version; 56385356398SRichard Weinberger __u32 align; 56485356398SRichard Weinberger char *backing_file; 56585356398SRichard Weinberger time_t mtime; 56685356398SRichard Weinberger unsigned long long size; 56785356398SRichard Weinberger int sector_size; 56885356398SRichard Weinberger int bitmap_offset; 56985356398SRichard Weinberger 57085356398SRichard Weinberger if (ubd_dev->file && ubd_dev->cow.file) { 57185356398SRichard Weinberger file = ubd_dev->cow.file; 57285356398SRichard Weinberger 57385356398SRichard Weinberger goto out; 57485356398SRichard Weinberger } 57585356398SRichard Weinberger 576d4afcba9SMartin Pärtel fd = os_open_file(ubd_dev->file, of_read(OPENFLAGS()), 0); 57785356398SRichard Weinberger if (fd < 0) 57885356398SRichard Weinberger return fd; 57985356398SRichard Weinberger 58085356398SRichard Weinberger err = read_cow_header(file_reader, &fd, &version, &backing_file, \ 58185356398SRichard Weinberger &mtime, &size, §or_size, &align, &bitmap_offset); 58285356398SRichard Weinberger os_close_file(fd); 58385356398SRichard Weinberger 58485356398SRichard Weinberger if(err == -EINVAL) 58585356398SRichard Weinberger file = ubd_dev->file; 58685356398SRichard Weinberger else 58785356398SRichard Weinberger file = backing_file; 58885356398SRichard Weinberger 58985356398SRichard Weinberger out: 590dc764e50SJeff Dike return os_file_size(file, size_out); 5911da177e4SLinus Torvalds } 5921da177e4SLinus Torvalds 5935dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 5945dc62b1bSWANG Cong { 5955dc62b1bSWANG Cong int err; 5965dc62b1bSWANG Cong 5978c6157b6SAnton Ivanov err = os_pread_file(fd, buf, len, offset); 5985dc62b1bSWANG Cong if (err < 0) 5995dc62b1bSWANG Cong return err; 6005dc62b1bSWANG Cong 6015dc62b1bSWANG Cong return 0; 6025dc62b1bSWANG Cong } 6035dc62b1bSWANG Cong 6045dc62b1bSWANG Cong static int backing_file_mismatch(char *file, __u64 size, time_t mtime) 6055dc62b1bSWANG Cong { 6065dc62b1bSWANG Cong unsigned long modtime; 6075dc62b1bSWANG Cong unsigned long long actual; 6085dc62b1bSWANG Cong int err; 6095dc62b1bSWANG Cong 6105dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 6115dc62b1bSWANG Cong if (err < 0) { 6125dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 6135dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 6145dc62b1bSWANG Cong return err; 6155dc62b1bSWANG Cong } 6165dc62b1bSWANG Cong 6175dc62b1bSWANG Cong err = os_file_size(file, &actual); 6185dc62b1bSWANG Cong if (err < 0) { 6195dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 6205dc62b1bSWANG Cong "err = %d\n", file, -err); 6215dc62b1bSWANG Cong return err; 6225dc62b1bSWANG Cong } 6235dc62b1bSWANG Cong 6245dc62b1bSWANG Cong if (actual != size) { 6255dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 6265dc62b1bSWANG Cong * the typecast.*/ 6275dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 6285dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 6295dc62b1bSWANG Cong return -EINVAL; 6305dc62b1bSWANG Cong } 6315dc62b1bSWANG Cong if (modtime != mtime) { 6325dc62b1bSWANG Cong printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " 6335dc62b1bSWANG Cong "backing file\n", mtime, modtime); 6345dc62b1bSWANG Cong return -EINVAL; 6355dc62b1bSWANG Cong } 6365dc62b1bSWANG Cong return 0; 6375dc62b1bSWANG Cong } 6385dc62b1bSWANG Cong 6395dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 6405dc62b1bSWANG Cong { 6415dc62b1bSWANG Cong struct uml_stat buf1, buf2; 6425dc62b1bSWANG Cong int err; 6435dc62b1bSWANG Cong 6445dc62b1bSWANG Cong if (from_cmdline == NULL) 6455dc62b1bSWANG Cong return 0; 6465dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 6475dc62b1bSWANG Cong return 0; 6485dc62b1bSWANG Cong 6495dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 6505dc62b1bSWANG Cong if (err < 0) { 6515dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 6525dc62b1bSWANG Cong -err); 6535dc62b1bSWANG Cong return 0; 6545dc62b1bSWANG Cong } 6555dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 6565dc62b1bSWANG Cong if (err < 0) { 6575dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 6585dc62b1bSWANG Cong -err); 6595dc62b1bSWANG Cong return 1; 6605dc62b1bSWANG Cong } 6615dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 6625dc62b1bSWANG Cong return 0; 6635dc62b1bSWANG Cong 6645dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 6655dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 6665dc62b1bSWANG Cong from_cmdline, from_cow, cow); 6675dc62b1bSWANG Cong return 1; 6685dc62b1bSWANG Cong } 6695dc62b1bSWANG Cong 6705dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 6715dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 6725dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6735dc62b1bSWANG Cong int *create_cow_out) 6745dc62b1bSWANG Cong { 6755dc62b1bSWANG Cong time_t mtime; 6765dc62b1bSWANG Cong unsigned long long size; 6775dc62b1bSWANG Cong __u32 version, align; 6785dc62b1bSWANG Cong char *backing_file; 6795dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6805dc62b1bSWANG Cong 6815dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6825dc62b1bSWANG Cong if (fd < 0) { 6835dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6845dc62b1bSWANG Cong *create_cow_out = 1; 6855dc62b1bSWANG Cong if (!openflags->w || 6865dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 6875dc62b1bSWANG Cong return fd; 6885dc62b1bSWANG Cong openflags->w = 0; 6895dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6905dc62b1bSWANG Cong if (fd < 0) 6915dc62b1bSWANG Cong return fd; 6925dc62b1bSWANG Cong } 6935dc62b1bSWANG Cong 6945dc62b1bSWANG Cong if (shared) 6955dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 6965dc62b1bSWANG Cong else { 6975dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 6985dc62b1bSWANG Cong if (err < 0) { 6995dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 7005dc62b1bSWANG Cong file, -err); 7015dc62b1bSWANG Cong goto out_close; 7025dc62b1bSWANG Cong } 7035dc62b1bSWANG Cong } 7045dc62b1bSWANG Cong 7055dc62b1bSWANG Cong /* Successful return case! */ 7065dc62b1bSWANG Cong if (backing_file_out == NULL) 7075dc62b1bSWANG Cong return fd; 7085dc62b1bSWANG Cong 7095dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 7105dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 7115dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 7125dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 7135dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 7145dc62b1bSWANG Cong goto out_close; 7155dc62b1bSWANG Cong } 7165dc62b1bSWANG Cong if (err) 7175dc62b1bSWANG Cong return fd; 7185dc62b1bSWANG Cong 7195dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 7205dc62b1bSWANG Cong file); 7215dc62b1bSWANG Cong 7225dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 7235dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 7245dc62b1bSWANG Cong mtime)) { 7255dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 7265dc62b1bSWANG Cong *backing_file_out); 7275dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 7285dc62b1bSWANG Cong sectorsize, align, &size); 7295dc62b1bSWANG Cong if (err) { 7305dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 7315dc62b1bSWANG Cong goto out_close; 7325dc62b1bSWANG Cong } 7335dc62b1bSWANG Cong } else { 7345dc62b1bSWANG Cong *backing_file_out = backing_file; 7355dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 7365dc62b1bSWANG Cong if (err) 7375dc62b1bSWANG Cong goto out_close; 7385dc62b1bSWANG Cong } 7395dc62b1bSWANG Cong 7405dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 7415dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 7425dc62b1bSWANG Cong 7435dc62b1bSWANG Cong return fd; 7445dc62b1bSWANG Cong out_close: 7455dc62b1bSWANG Cong os_close_file(fd); 7465dc62b1bSWANG Cong return err; 7475dc62b1bSWANG Cong } 7485dc62b1bSWANG Cong 7495dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 7505dc62b1bSWANG Cong struct openflags flags, 7515dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 7525dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 7535dc62b1bSWANG Cong { 7545dc62b1bSWANG Cong int err, fd; 7555dc62b1bSWANG Cong 7565dc62b1bSWANG Cong flags.c = 1; 7575dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 7585dc62b1bSWANG Cong if (fd < 0) { 7595dc62b1bSWANG Cong err = fd; 7605dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 7615dc62b1bSWANG Cong cow_file, -err); 7625dc62b1bSWANG Cong goto out; 7635dc62b1bSWANG Cong } 7645dc62b1bSWANG Cong 7655dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 7665dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 7675dc62b1bSWANG Cong data_offset_out); 7685dc62b1bSWANG Cong if (!err) 7695dc62b1bSWANG Cong return fd; 7705dc62b1bSWANG Cong os_close_file(fd); 7715dc62b1bSWANG Cong out: 7725dc62b1bSWANG Cong return err; 7735dc62b1bSWANG Cong } 7745dc62b1bSWANG Cong 7755f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7761da177e4SLinus Torvalds { 7777d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7787d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7791da177e4SLinus Torvalds return; 7801da177e4SLinus Torvalds 7817d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7827d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7837d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7841da177e4SLinus Torvalds } 7851da177e4SLinus Torvalds 7867d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 7871da177e4SLinus Torvalds { 7881da177e4SLinus Torvalds struct openflags flags; 7891da177e4SLinus Torvalds char **back_ptr; 7901da177e4SLinus Torvalds int err, create_cow, *create_ptr; 7910bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 7921da177e4SLinus Torvalds 7937d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 7941da177e4SLinus Torvalds create_cow = 0; 7957d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 7967d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 7970bf16bffSPaolo 'Blaisorblade' Giarrusso 7980bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 7997d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 8007d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 8016c29256cSJeff Dike create_ptr); 8021da177e4SLinus Torvalds 8030bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 8040bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 805a43c8316SAnton Ivanov ubd_dev->openflags, SECTOR_SIZE, PAGE_SIZE, 8067d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 8077d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 8087d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 8090bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 8101da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 8117d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 8121da177e4SLinus Torvalds } 8131da177e4SLinus Torvalds } 8141da177e4SLinus Torvalds 8150bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 8167d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 8170bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 8180bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 8191da177e4SLinus Torvalds } 8200bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 8211da177e4SLinus Torvalds 8227d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 823086fa5ffSMartin K. Petersen blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); 824f4768ffdSJeff Dike 8251da177e4SLinus Torvalds err = -ENOMEM; 826da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 8277d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 8281da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 8291da177e4SLinus Torvalds goto error; 8301da177e4SLinus Torvalds } 8311da177e4SLinus Torvalds flush_tlb_kernel_vm(); 8321da177e4SLinus Torvalds 8337d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 8347d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 8357d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 8361da177e4SLinus Torvalds if(err < 0) 8371da177e4SLinus Torvalds goto error; 8381da177e4SLinus Torvalds 8397d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 8401da177e4SLinus Torvalds flags.w = 0; 8417d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 8426c29256cSJeff Dike NULL, NULL, NULL, NULL); 8431da177e4SLinus Torvalds if(err < 0) goto error; 8447d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 8451da177e4SLinus Torvalds } 84650109b5aSAnton Ivanov if (ubd_dev->no_trim == 0) { 84750109b5aSAnton Ivanov ubd_dev->queue->limits.discard_granularity = SECTOR_SIZE; 84850109b5aSAnton Ivanov ubd_dev->queue->limits.discard_alignment = SECTOR_SIZE; 84950109b5aSAnton Ivanov blk_queue_max_discard_sectors(ubd_dev->queue, UBD_MAX_REQUEST); 85050109b5aSAnton Ivanov blk_queue_max_write_zeroes_sectors(ubd_dev->queue, UBD_MAX_REQUEST); 85150109b5aSAnton Ivanov blk_queue_flag_set(QUEUE_FLAG_DISCARD, ubd_dev->queue); 85250109b5aSAnton Ivanov } 853a43c8316SAnton Ivanov blk_queue_flag_set(QUEUE_FLAG_NONROT, ubd_dev->queue); 854dc764e50SJeff Dike return 0; 8551da177e4SLinus Torvalds error: 8567d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 857dc764e50SJeff Dike return err; 8581da177e4SLinus Torvalds } 8591da177e4SLinus Torvalds 8602e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 8612e3f5251SJeff Dike { 8628691b97bSGreg Kroah-Hartman struct ubd *ubd_dev = dev_get_drvdata(dev); 8632e3f5251SJeff Dike 8642e3f5251SJeff Dike blk_cleanup_queue(ubd_dev->queue); 8654e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 8662e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 8672e3f5251SJeff Dike } 8682e3f5251SJeff Dike 8695f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 8701da177e4SLinus Torvalds struct gendisk **disk_out) 8711da177e4SLinus Torvalds { 872d72a5783SDan Williams struct device *parent = NULL; 8731da177e4SLinus Torvalds struct gendisk *disk; 8741da177e4SLinus Torvalds 8751da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 8761da177e4SLinus Torvalds if(disk == NULL) 877dc764e50SJeff Dike return -ENOMEM; 8781da177e4SLinus Torvalds 8791da177e4SLinus Torvalds disk->major = major; 8801da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 8811da177e4SLinus Torvalds disk->fops = &ubd_blops; 8821da177e4SLinus Torvalds set_capacity(disk, size / 512); 883792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) 8841da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 885ce7b0f46SGreg Kroah-Hartman else 8861da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 8871da177e4SLinus Torvalds 8881da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 889792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) { 8907d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 8917d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 8922e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 8938691b97bSGreg Kroah-Hartman dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); 8947d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 895d72a5783SDan Williams parent = &ubd_devs[unit].pdev.dev; 8961da177e4SLinus Torvalds } 8971da177e4SLinus Torvalds 8987d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 89962f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 900fef912bfSHannes Reinecke device_add_disk(parent, disk, NULL); 9011da177e4SLinus Torvalds 9021da177e4SLinus Torvalds *disk_out = disk; 9031da177e4SLinus Torvalds return 0; 9041da177e4SLinus Torvalds } 9051da177e4SLinus Torvalds 906a43c8316SAnton Ivanov #define ROUND_BLOCK(n) ((n + (SECTOR_SIZE - 1)) & (-SECTOR_SIZE)) 9071da177e4SLinus Torvalds 9084e6da0feSRichard Weinberger static const struct blk_mq_ops ubd_mq_ops = { 9094e6da0feSRichard Weinberger .queue_rq = ubd_queue_rq, 9104e6da0feSRichard Weinberger }; 9114e6da0feSRichard Weinberger 912f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 9131da177e4SLinus Torvalds { 9147d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 915f28169d2SJeff Dike int err = 0; 9161da177e4SLinus Torvalds 9177d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 918ec7cf783SJeff Dike goto out; 9191da177e4SLinus Torvalds 9207d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 921f28169d2SJeff Dike if(err < 0){ 922f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 92380c13749SJeff Dike goto out; 924f28169d2SJeff Dike } 9251da177e4SLinus Torvalds 9267d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 9271da177e4SLinus Torvalds 9284e6da0feSRichard Weinberger ubd_dev->tag_set.ops = &ubd_mq_ops; 9294e6da0feSRichard Weinberger ubd_dev->tag_set.queue_depth = 64; 9304e6da0feSRichard Weinberger ubd_dev->tag_set.numa_node = NUMA_NO_NODE; 9314e6da0feSRichard Weinberger ubd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; 9324e6da0feSRichard Weinberger ubd_dev->tag_set.driver_data = ubd_dev; 9334e6da0feSRichard Weinberger ubd_dev->tag_set.nr_hw_queues = 1; 934a0044bdfSJeff Dike 9354e6da0feSRichard Weinberger err = blk_mq_alloc_tag_set(&ubd_dev->tag_set); 9364e6da0feSRichard Weinberger if (err) 93780c13749SJeff Dike goto out; 9384e6da0feSRichard Weinberger 9394e6da0feSRichard Weinberger ubd_dev->queue = blk_mq_init_queue(&ubd_dev->tag_set); 9404e6da0feSRichard Weinberger if (IS_ERR(ubd_dev->queue)) { 9414e6da0feSRichard Weinberger err = PTR_ERR(ubd_dev->queue); 942aea05eb5SAnton Ivanov goto out_cleanup_tags; 94362f96cb0SJeff Dike } 9444e6da0feSRichard Weinberger 94562f96cb0SJeff Dike ubd_dev->queue->queuedata = ubd_dev; 946f935a8ceSJens Axboe blk_queue_write_cache(ubd_dev->queue, true, false); 94762f96cb0SJeff Dike 9488a78362cSMartin K. Petersen blk_queue_max_segments(ubd_dev->queue, MAX_SG); 949792dd4fcSChristoph Hellwig err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); 95062f96cb0SJeff Dike if(err){ 95162f96cb0SJeff Dike *error_out = "Failed to register device"; 9524e6da0feSRichard Weinberger goto out_cleanup_tags; 95362f96cb0SJeff Dike } 9541da177e4SLinus Torvalds 955792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) 9565f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 9571da177e4SLinus Torvalds &fake_gendisk[n]); 9581da177e4SLinus Torvalds 95983380cc1SJeff Dike /* 96083380cc1SJeff Dike * Perhaps this should also be under the "if (fake_major)" above 96183380cc1SJeff Dike * using the fake_disk->disk_name 96283380cc1SJeff Dike */ 9631da177e4SLinus Torvalds if (fake_ide) 9641da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 9651da177e4SLinus Torvalds 966ec7cf783SJeff Dike err = 0; 967ec7cf783SJeff Dike out: 968ec7cf783SJeff Dike return err; 96962f96cb0SJeff Dike 9704e6da0feSRichard Weinberger out_cleanup_tags: 9714e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 972aea05eb5SAnton Ivanov if (!(IS_ERR(ubd_dev->queue))) 97362f96cb0SJeff Dike blk_cleanup_queue(ubd_dev->queue); 97462f96cb0SJeff Dike goto out; 9751da177e4SLinus Torvalds } 9761da177e4SLinus Torvalds 977f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 9781da177e4SLinus Torvalds { 979e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 9801da177e4SLinus Torvalds 981f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 982f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 983f28169d2SJeff Dike * were set. 984f28169d2SJeff Dike */ 985970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 9861da177e4SLinus Torvalds if (str == NULL) { 987f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 988f28169d2SJeff Dike return -ENOMEM; 9891da177e4SLinus Torvalds } 990f28169d2SJeff Dike 991f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 992f28169d2SJeff Dike if (ret) 993e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 994f28169d2SJeff Dike 995e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 996e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 997d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 998e7f6552fSPaolo 'Blaisorblade' Giarrusso } 9991da177e4SLinus Torvalds 1000d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 1001f28169d2SJeff Dike ret = ubd_add(n, error_out); 1002e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 10037d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 1004d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 10051da177e4SLinus Torvalds 1006e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 1007e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 1008e7f6552fSPaolo 'Blaisorblade' Giarrusso 1009e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 1010e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 1011e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 10121da177e4SLinus Torvalds } 10131da177e4SLinus Torvalds 10141da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 10151da177e4SLinus Torvalds { 10167d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 10171da177e4SLinus Torvalds int n, len = 0; 10181da177e4SLinus Torvalds 10191da177e4SLinus Torvalds n = parse_unit(&name); 10201da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 10211da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 1022dc764e50SJeff Dike return -1; 10231da177e4SLinus Torvalds } 10241da177e4SLinus Torvalds 10257d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 1026d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10271da177e4SLinus Torvalds 10287d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 10291da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 10301da177e4SLinus Torvalds goto out; 10311da177e4SLinus Torvalds } 10321da177e4SLinus Torvalds 10337d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 10341da177e4SLinus Torvalds 10357d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 10361da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 10377d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 10381da177e4SLinus Torvalds } 10391da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 10401da177e4SLinus Torvalds 10411da177e4SLinus Torvalds out: 1042d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 1043dc764e50SJeff Dike return len; 10441da177e4SLinus Torvalds } 10451da177e4SLinus Torvalds 104629d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 104729d56cfeSJeff Dike { 104829d56cfeSJeff Dike int n; 104929d56cfeSJeff Dike 105029d56cfeSJeff Dike n = parse_unit(str); 105129d56cfeSJeff Dike *start_out = 0; 105229d56cfeSJeff Dike *end_out = MAX_DEV - 1; 105329d56cfeSJeff Dike return n; 105429d56cfeSJeff Dike } 105529d56cfeSJeff Dike 1056f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 10571da177e4SLinus Torvalds { 10582e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 10597d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 106029d56cfeSJeff Dike int err = -ENODEV; 10611da177e4SLinus Torvalds 1062d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10631da177e4SLinus Torvalds 10647d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 106529d56cfeSJeff Dike 10667d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 106729d56cfeSJeff Dike goto out; 106829d56cfeSJeff Dike 106929d56cfeSJeff Dike /* you cannot remove a open disk */ 107029d56cfeSJeff Dike err = -EBUSY; 10717d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 107229d56cfeSJeff Dike goto out; 107329d56cfeSJeff Dike 10741da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 1075b47d2debSJeff Dike if(disk != NULL){ 1076b47d2debSJeff Dike del_gendisk(disk); 1077b47d2debSJeff Dike put_disk(disk); 1078b47d2debSJeff Dike } 10791da177e4SLinus Torvalds 10801da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 10811da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 10821da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 10831da177e4SLinus Torvalds fake_gendisk[n] = NULL; 10841da177e4SLinus Torvalds } 10851da177e4SLinus Torvalds 10861da177e4SLinus Torvalds err = 0; 10872e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 10881da177e4SLinus Torvalds out: 1089d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 109029d56cfeSJeff Dike return err; 10911da177e4SLinus Torvalds } 10921da177e4SLinus Torvalds 1093f28169d2SJeff Dike /* All these are called by mconsole in process context and without 1094b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 1095f28169d2SJeff Dike */ 10961da177e4SLinus Torvalds static struct mc_device ubd_mc = { 109784f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 10981da177e4SLinus Torvalds .name = "ubd", 10991da177e4SLinus Torvalds .config = ubd_config, 11001da177e4SLinus Torvalds .get_config = ubd_get_config, 110129d56cfeSJeff Dike .id = ubd_id, 11021da177e4SLinus Torvalds .remove = ubd_remove, 11031da177e4SLinus Torvalds }; 11041da177e4SLinus Torvalds 1105d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 11061da177e4SLinus Torvalds { 11071da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 11081da177e4SLinus Torvalds return 0; 11091da177e4SLinus Torvalds } 11101da177e4SLinus Torvalds 11111da177e4SLinus Torvalds __initcall(ubd_mc_init); 11121da177e4SLinus Torvalds 1113d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1114d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1115d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1116d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1117b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1118d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1119d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1120b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1121b8831a1dSJeff Dike 1122dc764e50SJeff Dike return 0; 1123d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1124d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1125d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1126d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1127b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 11283ae5eaecSRussell King static struct platform_driver ubd_driver = { 11293ae5eaecSRussell King .driver = { 11301da177e4SLinus Torvalds .name = DRIVER_NAME, 11313ae5eaecSRussell King }, 11321da177e4SLinus Torvalds }; 11331da177e4SLinus Torvalds 1134d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 11351da177e4SLinus Torvalds { 1136f28169d2SJeff Dike char *error; 1137f28169d2SJeff Dike int i, err; 11381da177e4SLinus Torvalds 1139792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 11401da177e4SLinus Torvalds return -1; 11411da177e4SLinus Torvalds 1142792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 11431da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 11441da177e4SLinus Torvalds 11451da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 11461da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 11471da177e4SLinus Torvalds return -1; 11481da177e4SLinus Torvalds } 1149f88f0bdfSAnton Ivanov 11506da2ec56SKees Cook irq_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11516da2ec56SKees Cook sizeof(struct io_thread_req *), 1152f88f0bdfSAnton Ivanov GFP_KERNEL 1153f88f0bdfSAnton Ivanov ); 1154f88f0bdfSAnton Ivanov irq_remainder = 0; 1155f88f0bdfSAnton Ivanov 1156f88f0bdfSAnton Ivanov if (irq_req_buffer == NULL) { 1157f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1158f88f0bdfSAnton Ivanov return -1; 1159f88f0bdfSAnton Ivanov } 11606da2ec56SKees Cook io_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11616da2ec56SKees Cook sizeof(struct io_thread_req *), 1162f88f0bdfSAnton Ivanov GFP_KERNEL 1163f88f0bdfSAnton Ivanov ); 1164f88f0bdfSAnton Ivanov 1165f88f0bdfSAnton Ivanov io_remainder = 0; 1166f88f0bdfSAnton Ivanov 1167f88f0bdfSAnton Ivanov if (io_req_buffer == NULL) { 1168f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1169f88f0bdfSAnton Ivanov return -1; 1170f88f0bdfSAnton Ivanov } 11713ae5eaecSRussell King platform_driver_register(&ubd_driver); 1172b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1173f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1174f28169d2SJeff Dike err = ubd_add(i, &error); 1175f28169d2SJeff Dike if(err) 1176f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1177f28169d2SJeff Dike "%s\n", i, error); 1178f28169d2SJeff Dike } 1179b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 11801da177e4SLinus Torvalds return 0; 11811da177e4SLinus Torvalds } 11821da177e4SLinus Torvalds 11831da177e4SLinus Torvalds late_initcall(ubd_init); 11841da177e4SLinus Torvalds 1185d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 118691acb21fSJeff Dike unsigned long stack; 118791acb21fSJeff Dike int err; 118891acb21fSJeff Dike 118991acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 119091acb21fSJeff Dike if(global_openflags.s){ 119191acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 119291acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 119391acb21fSJeff Dike * enough. So use anyway the io thread. */ 119491acb21fSJeff Dike } 119591acb21fSJeff Dike stack = alloc_stack(0, 0); 119691acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 119791acb21fSJeff Dike &thread_fd); 119891acb21fSJeff Dike if(io_pid < 0){ 119991acb21fSJeff Dike printk(KERN_ERR 120091acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 120191acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 120291acb21fSJeff Dike io_pid = -1; 1203dc764e50SJeff Dike return 0; 120491acb21fSJeff Dike } 120591acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 1206c0b79a90SYong Zhang 0, "ubd", ubd_devs); 120791acb21fSJeff Dike if(err != 0) 120891acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1209f4c57a78SJeff Dike return 0; 121091acb21fSJeff Dike } 121191acb21fSJeff Dike 121291acb21fSJeff Dike device_initcall(ubd_driver_init); 121391acb21fSJeff Dike 1214a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 12151da177e4SLinus Torvalds { 1216a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 12177d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12181da177e4SLinus Torvalds int err = 0; 12191da177e4SLinus Torvalds 12209a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12217d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 12227d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 12231da177e4SLinus Torvalds if(err){ 12241da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 12257d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 12261da177e4SLinus Torvalds goto out; 12271da177e4SLinus Torvalds } 12281da177e4SLinus Torvalds } 12297d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 12307d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 12312c49be99SPaolo 'Blaisorblade' Giarrusso 12322c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 12332c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1234a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 12355f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 12361da177e4SLinus Torvalds err = -EROFS; 12372c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 12381da177e4SLinus Torvalds out: 12399a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 1240dc764e50SJeff Dike return err; 12411da177e4SLinus Torvalds } 12421da177e4SLinus Torvalds 1243db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode) 12441da177e4SLinus Torvalds { 12457d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12461da177e4SLinus Torvalds 12479a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12487d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 12495f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 12509a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 12511da177e4SLinus Torvalds } 12521da177e4SLinus Torvalds 125391acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 125491acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 125591acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 125691acb21fSJeff Dike __u64 bitmap_len) 12571da177e4SLinus Torvalds { 1258a43c8316SAnton Ivanov __u64 sector = io_offset >> SECTOR_SHIFT; 125991acb21fSJeff Dike int i, update_bitmap = 0; 12601da177e4SLinus Torvalds 1261a43c8316SAnton Ivanov for (i = 0; i < length >> SECTOR_SHIFT; i++) { 126291acb21fSJeff Dike if(cow_mask != NULL) 126391acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 126491acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 126509ace81cSJeff Dike continue; 12661da177e4SLinus Torvalds 126791acb21fSJeff Dike update_bitmap = 1; 126891acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 12691da177e4SLinus Torvalds } 127091acb21fSJeff Dike 127191acb21fSJeff Dike if(!update_bitmap) 127291acb21fSJeff Dike return; 127391acb21fSJeff Dike 127491acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 127591acb21fSJeff Dike 127691acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 127791acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 127891acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 127991acb21fSJeff Dike * for the original diagnosis. 128091acb21fSJeff Dike */ 12816d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 12826d074242SJiri Olsa sizeof(unsigned long)) - 1)) 128391acb21fSJeff Dike (*cow_offset)--; 128491acb21fSJeff Dike 128591acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 128691acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 128791acb21fSJeff Dike 128891acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 128991acb21fSJeff Dike *cow_offset += bitmap_offset; 129091acb21fSJeff Dike } 129191acb21fSJeff Dike 129291acb21fSJeff Dike static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, 129391acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 129491acb21fSJeff Dike { 1295a43c8316SAnton Ivanov __u64 sector = req->offset >> SECTOR_SHIFT; 129691acb21fSJeff Dike int i; 129791acb21fSJeff Dike 1298a43c8316SAnton Ivanov if (req->length > (sizeof(req->sector_mask) * 8) << SECTOR_SHIFT) 129991acb21fSJeff Dike panic("Operation too long"); 130091acb21fSJeff Dike 1301a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_READ) { 1302a43c8316SAnton Ivanov for (i = 0; i < req->length >> SECTOR_SHIFT; i++) { 130391acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 130491acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 130591acb21fSJeff Dike &req->sector_mask); 130691acb21fSJeff Dike } 130791acb21fSJeff Dike } 130891acb21fSJeff Dike else cowify_bitmap(req->offset, req->length, &req->sector_mask, 130991acb21fSJeff Dike &req->cow_offset, bitmap, bitmap_offset, 131091acb21fSJeff Dike req->bitmap_words, bitmap_len); 13111da177e4SLinus Torvalds } 13121da177e4SLinus Torvalds 1313ecb0a83eSChristoph Hellwig static int ubd_queue_one_vec(struct blk_mq_hw_ctx *hctx, struct request *req, 1314ecb0a83eSChristoph Hellwig u64 off, struct bio_vec *bvec) 13151da177e4SLinus Torvalds { 1316ecb0a83eSChristoph Hellwig struct ubd *dev = hctx->queue->queuedata; 1317ecb0a83eSChristoph Hellwig struct io_thread_req *io_req; 1318ecb0a83eSChristoph Hellwig int ret; 1319ecb0a83eSChristoph Hellwig 1320ecb0a83eSChristoph Hellwig io_req = kmalloc(sizeof(struct io_thread_req), GFP_ATOMIC); 1321ecb0a83eSChristoph Hellwig if (!io_req) 1322ecb0a83eSChristoph Hellwig return -ENOMEM; 132391acb21fSJeff Dike 132462f96cb0SJeff Dike io_req->req = req; 1325ecb0a83eSChristoph Hellwig if (dev->cow.file) 1326ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->cow.fd; 1327ecb0a83eSChristoph Hellwig else 1328ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->fd; 13290033dfd9SAnton Ivanov io_req->error = 0; 1330ecb0a83eSChristoph Hellwig 133153766defSAnton Ivanov if (bvec != NULL) { 133253766defSAnton Ivanov io_req->buffer = page_address(bvec->bv_page) + bvec->bv_offset; 133353766defSAnton Ivanov io_req->length = bvec->bv_len; 133453766defSAnton Ivanov } else { 133553766defSAnton Ivanov io_req->buffer = NULL; 133653766defSAnton Ivanov io_req->length = blk_rq_bytes(req); 133753766defSAnton Ivanov } 133853766defSAnton Ivanov 133953766defSAnton Ivanov io_req->sectorsize = SECTOR_SIZE; 1340ecb0a83eSChristoph Hellwig io_req->fds[1] = dev->fd; 134191acb21fSJeff Dike io_req->cow_offset = -1; 1342ecb0a83eSChristoph Hellwig io_req->offset = off; 134391acb21fSJeff Dike io_req->sector_mask = 0; 13441da177e4SLinus Torvalds io_req->offsets[0] = 0; 1345ecb0a83eSChristoph Hellwig io_req->offsets[1] = dev->cow.data_offset; 13461da177e4SLinus Torvalds 134753766defSAnton Ivanov if (dev->cow.file) 1348ecb0a83eSChristoph Hellwig cowify_req(io_req, dev->cow.bitmap, 1349ecb0a83eSChristoph Hellwig dev->cow.bitmap_offset, dev->cow.bitmap_len); 13501da177e4SLinus Torvalds 1351ecb0a83eSChristoph Hellwig ret = os_write_file(thread_fd, &io_req, sizeof(io_req)); 1352ecb0a83eSChristoph Hellwig if (ret != sizeof(io_req)) { 1353ecb0a83eSChristoph Hellwig if (ret != -EAGAIN) 1354ecb0a83eSChristoph Hellwig pr_err("write to io thread failed: %d\n", -ret); 1355bc1d72e7SRichard Weinberger kfree(io_req); 1356bc1d72e7SRichard Weinberger } 1357ecb0a83eSChristoph Hellwig return ret; 1358bc1d72e7SRichard Weinberger } 1359bc1d72e7SRichard Weinberger 136053766defSAnton Ivanov static int queue_rw_req(struct blk_mq_hw_ctx *hctx, struct request *req) 136153766defSAnton Ivanov { 136253766defSAnton Ivanov struct req_iterator iter; 136353766defSAnton Ivanov struct bio_vec bvec; 136453766defSAnton Ivanov int ret; 136553766defSAnton Ivanov u64 off = (u64)blk_rq_pos(req) << SECTOR_SHIFT; 136653766defSAnton Ivanov 136753766defSAnton Ivanov rq_for_each_segment(bvec, req, iter) { 136853766defSAnton Ivanov ret = ubd_queue_one_vec(hctx, req, off, &bvec); 136953766defSAnton Ivanov if (ret < 0) 137053766defSAnton Ivanov return ret; 137153766defSAnton Ivanov off += bvec.bv_len; 137253766defSAnton Ivanov } 137353766defSAnton Ivanov return 0; 137453766defSAnton Ivanov } 137553766defSAnton Ivanov 13764e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 13774e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd) 13781da177e4SLinus Torvalds { 13796961cd4dSJens Axboe struct ubd *ubd_dev = hctx->queue->queuedata; 13804e6da0feSRichard Weinberger struct request *req = bd->rq; 138153766defSAnton Ivanov int ret = 0, res = BLK_STS_OK; 13821da177e4SLinus Torvalds 13834e6da0feSRichard Weinberger blk_mq_start_request(req); 1384a0044bdfSJeff Dike 13856961cd4dSJens Axboe spin_lock_irq(&ubd_dev->lock); 13866961cd4dSJens Axboe 138753766defSAnton Ivanov switch (req_op(req)) { 138853766defSAnton Ivanov /* operations with no lentgth/offset arguments */ 138953766defSAnton Ivanov case REQ_OP_FLUSH: 1390ecb0a83eSChristoph Hellwig ret = ubd_queue_one_vec(hctx, req, 0, NULL); 139153766defSAnton Ivanov break; 139253766defSAnton Ivanov case REQ_OP_READ: 139353766defSAnton Ivanov case REQ_OP_WRITE: 139453766defSAnton Ivanov ret = queue_rw_req(hctx, req); 139553766defSAnton Ivanov break; 139650109b5aSAnton Ivanov case REQ_OP_DISCARD: 139750109b5aSAnton Ivanov case REQ_OP_WRITE_ZEROES: 139850109b5aSAnton Ivanov ret = ubd_queue_one_vec(hctx, req, (u64)blk_rq_pos(req) << 9, NULL); 139950109b5aSAnton Ivanov break; 140053766defSAnton Ivanov default: 140153766defSAnton Ivanov WARN_ON_ONCE(1); 140253766defSAnton Ivanov res = BLK_STS_NOTSUPP; 140353766defSAnton Ivanov } 1404ecb0a83eSChristoph Hellwig 14056961cd4dSJens Axboe spin_unlock_irq(&ubd_dev->lock); 14066961cd4dSJens Axboe 1407d848074bSAnton Ivanov if (ret < 0) { 1408d848074bSAnton Ivanov if (ret == -ENOMEM) 1409d848074bSAnton Ivanov res = BLK_STS_RESOURCE; 1410d848074bSAnton Ivanov else 1411d848074bSAnton Ivanov res = BLK_STS_DEV_RESOURCE; 1412d848074bSAnton Ivanov } 14136961cd4dSJens Axboe 141453766defSAnton Ivanov return res; 141591acb21fSJeff Dike } 14164e6da0feSRichard Weinberger 1417a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1418a885c8c4SChristoph Hellwig { 14197d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1420a885c8c4SChristoph Hellwig 1421a885c8c4SChristoph Hellwig geo->heads = 128; 1422a885c8c4SChristoph Hellwig geo->sectors = 32; 14237d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1424a885c8c4SChristoph Hellwig return 0; 1425a885c8c4SChristoph Hellwig } 1426a885c8c4SChristoph Hellwig 1427a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 14281da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 14291da177e4SLinus Torvalds { 1430a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 143173855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 14321da177e4SLinus Torvalds 14331da177e4SLinus Torvalds switch (cmd) { 14341da177e4SLinus Torvalds struct cdrom_volctrl volume; 14351da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 143673855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 143773855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 143873855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 143973855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 14401da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 14411da177e4SLinus Torvalds sizeof(ubd_id))) 1442dc764e50SJeff Dike return -EFAULT; 1443dc764e50SJeff Dike return 0; 14441da177e4SLinus Torvalds 14451da177e4SLinus Torvalds case CDROMVOLREAD: 14461da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1447dc764e50SJeff Dike return -EFAULT; 14481da177e4SLinus Torvalds volume.channel0 = 255; 14491da177e4SLinus Torvalds volume.channel1 = 255; 14501da177e4SLinus Torvalds volume.channel2 = 255; 14511da177e4SLinus Torvalds volume.channel3 = 255; 14521da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1453dc764e50SJeff Dike return -EFAULT; 1454dc764e50SJeff Dike return 0; 14551da177e4SLinus Torvalds } 1456dc764e50SJeff Dike return -EINVAL; 14571da177e4SLinus Torvalds } 14581da177e4SLinus Torvalds 1459a43c8316SAnton Ivanov static int map_error(int error_code) 1460a43c8316SAnton Ivanov { 1461a43c8316SAnton Ivanov switch (error_code) { 1462a43c8316SAnton Ivanov case 0: 1463a43c8316SAnton Ivanov return BLK_STS_OK; 1464a43c8316SAnton Ivanov case ENOSYS: 1465a43c8316SAnton Ivanov case EOPNOTSUPP: 1466a43c8316SAnton Ivanov return BLK_STS_NOTSUPP; 1467a43c8316SAnton Ivanov case ENOSPC: 1468a43c8316SAnton Ivanov return BLK_STS_NOSPC; 1469a43c8316SAnton Ivanov } 1470a43c8316SAnton Ivanov return BLK_STS_IOERR; 1471a43c8316SAnton Ivanov } 1472a43c8316SAnton Ivanov 1473a41421edSAnton Ivanov /* 1474a41421edSAnton Ivanov * Everything from here onwards *IS NOT PART OF THE KERNEL* 1475a41421edSAnton Ivanov * 1476a41421edSAnton Ivanov * The following functions are part of UML hypervisor code. 1477a41421edSAnton Ivanov * All functions from here onwards are executed as a helper 1478a41421edSAnton Ivanov * thread and are not allowed to execute any kernel functions. 1479a41421edSAnton Ivanov * 1480a41421edSAnton Ivanov * Any communication must occur strictly via shared memory and IPC. 1481a41421edSAnton Ivanov * 1482a41421edSAnton Ivanov * Do not add printks, locks, kernel memory operations, etc - it 1483a41421edSAnton Ivanov * will result in unpredictable behaviour and/or crashes. 1484a41421edSAnton Ivanov */ 1485a41421edSAnton Ivanov 148691acb21fSJeff Dike static int update_bitmap(struct io_thread_req *req) 14871da177e4SLinus Torvalds { 148891acb21fSJeff Dike int n; 148991acb21fSJeff Dike 149091acb21fSJeff Dike if(req->cow_offset == -1) 1491a43c8316SAnton Ivanov return map_error(0); 149291acb21fSJeff Dike 14938c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[1], &req->bitmap_words, 14948c6157b6SAnton Ivanov sizeof(req->bitmap_words), req->cow_offset); 1495a41421edSAnton Ivanov if (n != sizeof(req->bitmap_words)) 1496a43c8316SAnton Ivanov return map_error(-n); 149791acb21fSJeff Dike 1498a43c8316SAnton Ivanov return map_error(0); 149991acb21fSJeff Dike } 150091acb21fSJeff Dike 15015dc62b1bSWANG Cong static void do_io(struct io_thread_req *req) 150291acb21fSJeff Dike { 150350109b5aSAnton Ivanov char *buf = NULL; 150491acb21fSJeff Dike unsigned long len; 150591acb21fSJeff Dike int n, nsectors, start, end, bit; 15061da177e4SLinus Torvalds __u64 off; 15071da177e4SLinus Torvalds 150850109b5aSAnton Ivanov /* FLUSH is really a special case, we cannot "case" it with others */ 150950109b5aSAnton Ivanov 1510a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_FLUSH) { 1511805f11a0SRichard Weinberger /* fds[0] is always either the rw image or our cow file */ 1512a41421edSAnton Ivanov req->error = map_error(-os_sync_file(req->fds[0])); 1513805f11a0SRichard Weinberger return; 1514805f11a0SRichard Weinberger } 1515805f11a0SRichard Weinberger 15161da177e4SLinus Torvalds nsectors = req->length / req->sectorsize; 15171da177e4SLinus Torvalds start = 0; 15181da177e4SLinus Torvalds do { 151991acb21fSJeff Dike bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); 15201da177e4SLinus Torvalds end = start; 15211da177e4SLinus Torvalds while((end < nsectors) && 152291acb21fSJeff Dike (ubd_test_bit(end, (unsigned char *) 152391acb21fSJeff Dike &req->sector_mask) == bit)) 15241da177e4SLinus Torvalds end++; 15251da177e4SLinus Torvalds 152691acb21fSJeff Dike off = req->offset + req->offsets[bit] + 15271da177e4SLinus Torvalds start * req->sectorsize; 15281da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 152950109b5aSAnton Ivanov if (req->buffer != NULL) 15301da177e4SLinus Torvalds buf = &req->buffer[start * req->sectorsize]; 15311da177e4SLinus Torvalds 153250109b5aSAnton Ivanov switch (req_op(req->req)) { 153350109b5aSAnton Ivanov case REQ_OP_READ: 153491acb21fSJeff Dike n = 0; 153591acb21fSJeff Dike do { 153691acb21fSJeff Dike buf = &buf[n]; 153791acb21fSJeff Dike len -= n; 15388c6157b6SAnton Ivanov n = os_pread_file(req->fds[bit], buf, len, off); 153991acb21fSJeff Dike if (n < 0) { 1540a43c8316SAnton Ivanov req->error = map_error(-n); 15411da177e4SLinus Torvalds return; 15421da177e4SLinus Torvalds } 154391acb21fSJeff Dike } while((n < len) && (n != 0)); 154491acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 154550109b5aSAnton Ivanov break; 154650109b5aSAnton Ivanov case REQ_OP_WRITE: 15478c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[bit], buf, len, off); 154891acb21fSJeff Dike if(n != len){ 1549a43c8316SAnton Ivanov req->error = map_error(-n); 155091acb21fSJeff Dike return; 155191acb21fSJeff Dike } 155250109b5aSAnton Ivanov break; 155350109b5aSAnton Ivanov case REQ_OP_DISCARD: 155450109b5aSAnton Ivanov case REQ_OP_WRITE_ZEROES: 155550109b5aSAnton Ivanov n = os_falloc_punch(req->fds[bit], off, len); 155650109b5aSAnton Ivanov if (n) { 155750109b5aSAnton Ivanov req->error = map_error(-n); 155850109b5aSAnton Ivanov return; 155950109b5aSAnton Ivanov } 156050109b5aSAnton Ivanov break; 156150109b5aSAnton Ivanov default: 156250109b5aSAnton Ivanov WARN_ON_ONCE(1); 156350109b5aSAnton Ivanov req->error = BLK_STS_NOTSUPP; 156450109b5aSAnton Ivanov return; 156591acb21fSJeff Dike } 15661da177e4SLinus Torvalds 15671da177e4SLinus Torvalds start = end; 15681da177e4SLinus Torvalds } while(start < nsectors); 156991acb21fSJeff Dike 157091acb21fSJeff Dike req->error = update_bitmap(req); 15711da177e4SLinus Torvalds } 157291acb21fSJeff Dike 157391acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 157491acb21fSJeff Dike * from ubd_init, which is an initcall. 157591acb21fSJeff Dike */ 157691acb21fSJeff Dike int kernel_fd = -1; 157791acb21fSJeff Dike 1578d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1579d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 158091acb21fSJeff Dike 158191acb21fSJeff Dike int io_thread(void *arg) 158291acb21fSJeff Dike { 1583f88f0bdfSAnton Ivanov int n, count, written, res; 158491acb21fSJeff Dike 158591d44ff8SRichard Weinberger os_fix_helper_signals(); 158691d44ff8SRichard Weinberger 158791acb21fSJeff Dike while(1){ 1588f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 1589f88f0bdfSAnton Ivanov kernel_fd, 1590f88f0bdfSAnton Ivanov io_req_buffer, 1591f88f0bdfSAnton Ivanov &io_remainder, 1592f88f0bdfSAnton Ivanov &io_remainder_size, 1593f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 1594f88f0bdfSAnton Ivanov ); 1595f88f0bdfSAnton Ivanov if (n < 0) { 1596f88f0bdfSAnton Ivanov if (n == -EAGAIN) { 1597f88f0bdfSAnton Ivanov ubd_read_poll(-1); 1598f88f0bdfSAnton Ivanov continue; 1599f88f0bdfSAnton Ivanov } 1600f88f0bdfSAnton Ivanov } 1601f88f0bdfSAnton Ivanov 1602f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 1603f88f0bdfSAnton Ivanov io_count++; 1604f88f0bdfSAnton Ivanov do_io((*io_req_buffer)[count]); 1605f88f0bdfSAnton Ivanov } 1606f88f0bdfSAnton Ivanov 1607f88f0bdfSAnton Ivanov written = 0; 1608f88f0bdfSAnton Ivanov 1609f88f0bdfSAnton Ivanov do { 1610f88f0bdfSAnton Ivanov res = os_write_file(kernel_fd, ((char *) io_req_buffer) + written, n); 1611ff6a1798SAnton Ivanov if (res >= 0) { 1612f88f0bdfSAnton Ivanov written += res; 161391acb21fSJeff Dike } 1614f88f0bdfSAnton Ivanov if (written < n) { 1615f88f0bdfSAnton Ivanov ubd_write_poll(-1); 1616f88f0bdfSAnton Ivanov } 1617f88f0bdfSAnton Ivanov } while (written < n); 161891acb21fSJeff Dike } 161991acb21fSJeff Dike 16201b57e9c2SJeff Dike return 0; 16211b57e9c2SJeff Dike } 1622