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 50fc6b6a87SGabriel Krisman Bertazi struct io_desc { 51fc6b6a87SGabriel Krisman Bertazi char *buffer; 52fc6b6a87SGabriel Krisman Bertazi unsigned long length; 53fc6b6a87SGabriel Krisman Bertazi unsigned long sector_mask; 54fc6b6a87SGabriel Krisman Bertazi unsigned long long cow_offset; 55fc6b6a87SGabriel Krisman Bertazi unsigned long bitmap_words[2]; 56fc6b6a87SGabriel Krisman Bertazi }; 57fc6b6a87SGabriel Krisman Bertazi 581da177e4SLinus Torvalds struct io_thread_req { 5962f96cb0SJeff Dike struct request *req; 601da177e4SLinus Torvalds int fds[2]; 611da177e4SLinus Torvalds unsigned long offsets[2]; 621da177e4SLinus Torvalds unsigned long long offset; 631da177e4SLinus Torvalds int sectorsize; 641da177e4SLinus Torvalds int error; 65fc6b6a87SGabriel Krisman Bertazi 66fc6b6a87SGabriel Krisman Bertazi int desc_cnt; 67fc6b6a87SGabriel Krisman Bertazi /* io_desc has to be the last element of the struct */ 68fc6b6a87SGabriel Krisman Bertazi struct io_desc io_desc[]; 691da177e4SLinus Torvalds }; 701da177e4SLinus Torvalds 71f88f0bdfSAnton Ivanov 72f88f0bdfSAnton Ivanov static struct io_thread_req * (*irq_req_buffer)[]; 73f88f0bdfSAnton Ivanov static struct io_thread_req *irq_remainder; 74f88f0bdfSAnton Ivanov static int irq_remainder_size; 75f88f0bdfSAnton Ivanov 76f88f0bdfSAnton Ivanov static struct io_thread_req * (*io_req_buffer)[]; 77f88f0bdfSAnton Ivanov static struct io_thread_req *io_remainder; 78f88f0bdfSAnton Ivanov static int io_remainder_size; 79f88f0bdfSAnton Ivanov 80f88f0bdfSAnton Ivanov 81f88f0bdfSAnton Ivanov 8291acb21fSJeff Dike static inline int ubd_test_bit(__u64 bit, unsigned char *data) 831da177e4SLinus Torvalds { 841da177e4SLinus Torvalds __u64 n; 851da177e4SLinus Torvalds int bits, off; 861da177e4SLinus Torvalds 8791acb21fSJeff Dike bits = sizeof(data[0]) * 8; 881da177e4SLinus Torvalds n = bit / bits; 891da177e4SLinus Torvalds off = bit % bits; 90dc764e50SJeff Dike return (data[n] & (1 << off)) != 0; 911da177e4SLinus Torvalds } 921da177e4SLinus Torvalds 9391acb21fSJeff Dike static inline void ubd_set_bit(__u64 bit, unsigned char *data) 941da177e4SLinus Torvalds { 951da177e4SLinus Torvalds __u64 n; 961da177e4SLinus Torvalds int bits, off; 971da177e4SLinus Torvalds 9891acb21fSJeff Dike bits = sizeof(data[0]) * 8; 991da177e4SLinus Torvalds n = bit / bits; 1001da177e4SLinus Torvalds off = bit % bits; 10191acb21fSJeff Dike data[n] |= (1 << off); 1021da177e4SLinus Torvalds } 1031da177e4SLinus Torvalds /*End stuff from ubd_user.h*/ 1041da177e4SLinus Torvalds 1051da177e4SLinus Torvalds #define DRIVER_NAME "uml-blkdev" 1061da177e4SLinus Torvalds 107d7fb2c38SPaolo 'Blaisorblade' Giarrusso static DEFINE_MUTEX(ubd_lock); 1089a181c58SArnd Bergmann static DEFINE_MUTEX(ubd_mutex); /* replaces BKL, might not be needed */ 1091da177e4SLinus Torvalds 110a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode); 111db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode); 112a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 1131da177e4SLinus Torvalds unsigned int cmd, unsigned long arg); 114a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); 1151da177e4SLinus Torvalds 11697d88ac8SPaolo 'Blaisorblade' Giarrusso #define MAX_DEV (16) 1171da177e4SLinus Torvalds 11883d5cde4SAlexey Dobriyan static const struct block_device_operations ubd_blops = { 1191da177e4SLinus Torvalds .owner = THIS_MODULE, 120a625c998SAl Viro .open = ubd_open, 121a625c998SAl Viro .release = ubd_release, 122a625c998SAl Viro .ioctl = ubd_ioctl, 123ab0cf1e4SArnd Bergmann .compat_ioctl = blkdev_compat_ptr_ioctl, 124a885c8c4SChristoph Hellwig .getgeo = ubd_getgeo, 1251da177e4SLinus Torvalds }; 1261da177e4SLinus Torvalds 1271da177e4SLinus Torvalds /* Protected by ubd_lock */ 128792dd4fcSChristoph Hellwig static int fake_major = UBD_MAJOR; 1291da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1301da177e4SLinus Torvalds static struct gendisk *fake_gendisk[MAX_DEV]; 1311da177e4SLinus Torvalds 1321da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1331da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1341da177e4SLinus Torvalds .cl = 1 }) 1351da177e4SLinus Torvalds #else 1361da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1371da177e4SLinus Torvalds .cl = 1 }) 1381da177e4SLinus Torvalds #endif 1391da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1401da177e4SLinus Torvalds 1411da177e4SLinus Torvalds struct cow { 1422a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file name */ 1431da177e4SLinus Torvalds char *file; 1442a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file fd */ 1451da177e4SLinus Torvalds int fd; 1461da177e4SLinus Torvalds unsigned long *bitmap; 1471da177e4SLinus Torvalds unsigned long bitmap_len; 1481da177e4SLinus Torvalds int bitmap_offset; 1491da177e4SLinus Torvalds int data_offset; 1501da177e4SLinus Torvalds }; 1511da177e4SLinus Torvalds 152a0044bdfSJeff Dike #define MAX_SG 64 153a0044bdfSJeff Dike 1541da177e4SLinus Torvalds struct ubd { 1552a9d32f6SPaolo 'Blaisorblade' Giarrusso /* name (and fd, below) of the file opened for writing, either the 1562a9d32f6SPaolo 'Blaisorblade' Giarrusso * backing or the cow file. */ 1571da177e4SLinus Torvalds char *file; 158ef3ba87cSChristopher Obbard char *serial; 1591da177e4SLinus Torvalds int count; 1601da177e4SLinus Torvalds int fd; 1611da177e4SLinus Torvalds __u64 size; 1621da177e4SLinus Torvalds struct openflags boot_openflags; 1631da177e4SLinus Torvalds struct openflags openflags; 16484e945e3SPaolo 'Blaisorblade' Giarrusso unsigned shared:1; 16584e945e3SPaolo 'Blaisorblade' Giarrusso unsigned no_cow:1; 16650109b5aSAnton Ivanov unsigned no_trim:1; 1671da177e4SLinus Torvalds struct cow cow; 1681da177e4SLinus Torvalds struct platform_device pdev; 16962f96cb0SJeff Dike struct request_queue *queue; 1704e6da0feSRichard Weinberger struct blk_mq_tag_set tag_set; 17162f96cb0SJeff Dike spinlock_t lock; 1724e6da0feSRichard Weinberger }; 1734e6da0feSRichard Weinberger 1741da177e4SLinus Torvalds #define DEFAULT_COW { \ 1751da177e4SLinus Torvalds .file = NULL, \ 1761da177e4SLinus Torvalds .fd = -1, \ 1771da177e4SLinus Torvalds .bitmap = NULL, \ 1781da177e4SLinus Torvalds .bitmap_offset = 0, \ 1791da177e4SLinus Torvalds .data_offset = 0, \ 1801da177e4SLinus Torvalds } 1811da177e4SLinus Torvalds 1821da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1831da177e4SLinus Torvalds .file = NULL, \ 184ef3ba87cSChristopher Obbard .serial = NULL, \ 1851da177e4SLinus Torvalds .count = 0, \ 1861da177e4SLinus Torvalds .fd = -1, \ 1871da177e4SLinus Torvalds .size = -1, \ 1881da177e4SLinus Torvalds .boot_openflags = OPEN_FLAGS, \ 1891da177e4SLinus Torvalds .openflags = OPEN_FLAGS, \ 1901da177e4SLinus Torvalds .no_cow = 0, \ 19150109b5aSAnton Ivanov .no_trim = 0, \ 1926c29256cSJeff Dike .shared = 0, \ 1931da177e4SLinus Torvalds .cow = DEFAULT_COW, \ 19422e65004SThomas Gleixner .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \ 1951da177e4SLinus Torvalds } 1961da177e4SLinus Torvalds 197b8831a1dSJeff Dike /* Protected by ubd_lock */ 1985dc62b1bSWANG Cong static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; 1991da177e4SLinus Torvalds 2001da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 2011da177e4SLinus Torvalds static int fake_ide = 0; 2021da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 2031da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 2041da177e4SLinus Torvalds 2054e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 2064e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd); 2074e6da0feSRichard Weinberger 2081da177e4SLinus Torvalds static void make_proc_ide(void) 2091da177e4SLinus Torvalds { 2101da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 2111da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 2121da177e4SLinus Torvalds } 2131da177e4SLinus Torvalds 2146613c5e8SAlexey Dobriyan static int fake_ide_media_proc_show(struct seq_file *m, void *v) 2151da177e4SLinus Torvalds { 2166613c5e8SAlexey Dobriyan seq_puts(m, "disk\n"); 2176613c5e8SAlexey Dobriyan return 0; 2186613c5e8SAlexey Dobriyan } 2191da177e4SLinus Torvalds 220c0a9290eSWANG Cong static void make_ide_entries(const char *dev_name) 2211da177e4SLinus Torvalds { 2221da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2231da177e4SLinus Torvalds char name[64]; 2241da177e4SLinus Torvalds 2251da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2261da177e4SLinus Torvalds 2271da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2281da177e4SLinus Torvalds if(!dir) return; 2291da177e4SLinus Torvalds 2303f3942acSChristoph Hellwig ent = proc_create_single("media", S_IRUGO, dir, 2313f3942acSChristoph Hellwig fake_ide_media_proc_show); 2321da177e4SLinus Torvalds if(!ent) return; 233c0a9290eSWANG Cong snprintf(name, sizeof(name), "ide0/%s", dev_name); 2341da177e4SLinus Torvalds proc_symlink(dev_name, proc_ide_root, name); 2351da177e4SLinus Torvalds } 2361da177e4SLinus Torvalds 2371da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2381da177e4SLinus Torvalds { 2391da177e4SLinus Torvalds fake_ide = 1; 240dc764e50SJeff Dike return 1; 2411da177e4SLinus Torvalds } 2421da177e4SLinus Torvalds 2431da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2441da177e4SLinus Torvalds 2451da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2461da177e4SLinus Torvalds "fake_ide\n" 2471da177e4SLinus Torvalds " Create ide0 entries that map onto ubd devices.\n\n" 2481da177e4SLinus Torvalds ); 2491da177e4SLinus Torvalds 2501da177e4SLinus Torvalds static int parse_unit(char **ptr) 2511da177e4SLinus Torvalds { 2521da177e4SLinus Torvalds char *str = *ptr, *end; 2531da177e4SLinus Torvalds int n = -1; 2541da177e4SLinus Torvalds 2551da177e4SLinus Torvalds if(isdigit(*str)) { 2561da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2571da177e4SLinus Torvalds if(end == str) 258dc764e50SJeff Dike return -1; 2591da177e4SLinus Torvalds *ptr = end; 2601da177e4SLinus Torvalds } 26197d88ac8SPaolo 'Blaisorblade' Giarrusso else if (('a' <= *str) && (*str <= 'z')) { 2621da177e4SLinus Torvalds n = *str - 'a'; 2631da177e4SLinus Torvalds str++; 2641da177e4SLinus Torvalds *ptr = str; 2651da177e4SLinus Torvalds } 266dc764e50SJeff Dike return n; 2671da177e4SLinus Torvalds } 2681da177e4SLinus Torvalds 269d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* If *index_out == -1 at exit, the passed option was a general one; 270d8d7c28eSPaolo 'Blaisorblade' Giarrusso * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it 271d8d7c28eSPaolo 'Blaisorblade' Giarrusso * should not be freed on exit. 272d8d7c28eSPaolo 'Blaisorblade' Giarrusso */ 273f28169d2SJeff Dike static int ubd_setup_common(char *str, int *index_out, char **error_out) 2741da177e4SLinus Torvalds { 2757d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 2761da177e4SLinus Torvalds struct openflags flags = global_openflags; 277ef3ba87cSChristopher Obbard char *file, *backing_file, *serial; 278b8831a1dSJeff Dike int n, err = 0, i; 2791da177e4SLinus Torvalds 2801da177e4SLinus Torvalds if(index_out) *index_out = -1; 2811da177e4SLinus Torvalds n = *str; 2821da177e4SLinus Torvalds if(n == '='){ 2831da177e4SLinus Torvalds char *end; 2841da177e4SLinus Torvalds int major; 2851da177e4SLinus Torvalds 2861da177e4SLinus Torvalds str++; 2871da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 2881da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 2899ca55299SDaniel Walter return err; 2901da177e4SLinus Torvalds } 2911da177e4SLinus Torvalds 292f28169d2SJeff Dike err = -EINVAL; 293b8831a1dSJeff Dike major = simple_strtoul(str, &end, 0); 294b8831a1dSJeff Dike if((*end != '\0') || (end == str)){ 295b8831a1dSJeff Dike *error_out = "Didn't parse major number"; 2969ca55299SDaniel Walter return err; 297b8831a1dSJeff Dike } 298b8831a1dSJeff Dike 299d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 300792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 301f28169d2SJeff Dike *error_out = "Can't assign a fake major twice"; 3021da177e4SLinus Torvalds goto out1; 3031da177e4SLinus Torvalds } 3041da177e4SLinus Torvalds 3051da177e4SLinus Torvalds fake_major = major; 3061da177e4SLinus Torvalds 3071da177e4SLinus Torvalds printk(KERN_INFO "Setting extra ubd major number to %d\n", 3081da177e4SLinus Torvalds major); 3091da177e4SLinus Torvalds err = 0; 3101da177e4SLinus Torvalds out1: 311d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 312f28169d2SJeff Dike return err; 3131da177e4SLinus Torvalds } 3141da177e4SLinus Torvalds 3151da177e4SLinus Torvalds n = parse_unit(&str); 3161da177e4SLinus Torvalds if(n < 0){ 317f28169d2SJeff Dike *error_out = "Couldn't parse device number"; 318f28169d2SJeff Dike return -EINVAL; 3191da177e4SLinus Torvalds } 3201da177e4SLinus Torvalds if(n >= MAX_DEV){ 321f28169d2SJeff Dike *error_out = "Device number out of range"; 322f28169d2SJeff Dike return 1; 3231da177e4SLinus Torvalds } 3241da177e4SLinus Torvalds 325f28169d2SJeff Dike err = -EBUSY; 326d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 3271da177e4SLinus Torvalds 3287d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 3297d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file != NULL){ 330f28169d2SJeff Dike *error_out = "Device is already configured"; 3311da177e4SLinus Torvalds goto out; 3321da177e4SLinus Torvalds } 3331da177e4SLinus Torvalds 3341da177e4SLinus Torvalds if (index_out) 3351da177e4SLinus Torvalds *index_out = n; 3361da177e4SLinus Torvalds 337f28169d2SJeff Dike err = -EINVAL; 33850109b5aSAnton Ivanov for (i = 0; i < sizeof("rscdt="); i++) { 3391da177e4SLinus Torvalds switch (*str) { 3401da177e4SLinus Torvalds case 'r': 3411da177e4SLinus Torvalds flags.w = 0; 3421da177e4SLinus Torvalds break; 3431da177e4SLinus Torvalds case 's': 3441da177e4SLinus Torvalds flags.s = 1; 3451da177e4SLinus Torvalds break; 3461da177e4SLinus Torvalds case 'd': 3477d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->no_cow = 1; 3481da177e4SLinus Torvalds break; 3496c29256cSJeff Dike case 'c': 3507d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->shared = 1; 3516c29256cSJeff Dike break; 35250109b5aSAnton Ivanov case 't': 35350109b5aSAnton Ivanov ubd_dev->no_trim = 1; 35450109b5aSAnton Ivanov break; 3551da177e4SLinus Torvalds case '=': 3561da177e4SLinus Torvalds str++; 3571da177e4SLinus Torvalds goto break_loop; 3581da177e4SLinus Torvalds default: 359f28169d2SJeff Dike *error_out = "Expected '=' or flag letter " 36050109b5aSAnton Ivanov "(r, s, c, t or d)"; 3611da177e4SLinus Torvalds goto out; 3621da177e4SLinus Torvalds } 3631da177e4SLinus Torvalds str++; 3641da177e4SLinus Torvalds } 3651da177e4SLinus Torvalds 3661da177e4SLinus Torvalds if (*str == '=') 367f28169d2SJeff Dike *error_out = "Too many flags specified"; 3681da177e4SLinus Torvalds else 369f28169d2SJeff Dike *error_out = "Missing '='"; 3701da177e4SLinus Torvalds goto out; 3711da177e4SLinus Torvalds 3721da177e4SLinus Torvalds break_loop: 373ef3ba87cSChristopher Obbard file = strsep(&str, ",:"); 374ef3ba87cSChristopher Obbard if (*file == '\0') 375ef3ba87cSChristopher Obbard file = NULL; 3761da177e4SLinus Torvalds 377ef3ba87cSChristopher Obbard backing_file = strsep(&str, ",:"); 378*94c41b3aSHajime Tazaki if (backing_file && *backing_file == '\0') 379ef3ba87cSChristopher Obbard backing_file = NULL; 3801da177e4SLinus Torvalds 381ef3ba87cSChristopher Obbard serial = strsep(&str, ",:"); 382*94c41b3aSHajime Tazaki if (serial && *serial == '\0') 383ef3ba87cSChristopher Obbard serial = NULL; 384ef3ba87cSChristopher Obbard 385ef3ba87cSChristopher Obbard if (backing_file && ubd_dev->no_cow) { 386f28169d2SJeff Dike *error_out = "Can't specify both 'd' and a cow file"; 387f28169d2SJeff Dike goto out; 388f28169d2SJeff Dike } 389ef3ba87cSChristopher Obbard 390f28169d2SJeff Dike err = 0; 391ef3ba87cSChristopher Obbard ubd_dev->file = file; 3927d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.file = backing_file; 393ef3ba87cSChristopher Obbard ubd_dev->serial = serial; 3947d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->boot_openflags = flags; 3951da177e4SLinus Torvalds out: 396d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 397f28169d2SJeff Dike return err; 3981da177e4SLinus Torvalds } 3991da177e4SLinus Torvalds 4001da177e4SLinus Torvalds static int ubd_setup(char *str) 4011da177e4SLinus Torvalds { 402f28169d2SJeff Dike char *error; 403f28169d2SJeff Dike int err; 404f28169d2SJeff Dike 405f28169d2SJeff Dike err = ubd_setup_common(str, NULL, &error); 406f28169d2SJeff Dike if(err) 407f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize device with \"%s\" : " 408f28169d2SJeff Dike "%s\n", str, error); 409f28169d2SJeff Dike return 1; 4101da177e4SLinus Torvalds } 4111da177e4SLinus Torvalds 4121da177e4SLinus Torvalds __setup("ubd", ubd_setup); 4131da177e4SLinus Torvalds __uml_help(ubd_setup, 414ef3ba87cSChristopher Obbard "ubd<n><flags>=<filename>[(:|,)<filename2>][(:|,)<serial>]\n" 4151da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 4161da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 4171da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 4181da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 4191da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 4201da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 421f28169d2SJeff Dike " When using only one filename, UML will detect whether to treat it like\n" 4221da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 4231da177e4SLinus Torvalds " flag:\n" 4241da177e4SLinus Torvalds " ubd0d=BackingFile\n" 4251da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 4261da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 4271da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 4281da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 4291da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 4301da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 4311da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 43220ede453SJeff Dike " an 's' will cause data to be written to disk on the host immediately.\n" 43320ede453SJeff Dike " 'c' will cause the device to be treated as being shared between multiple\n" 43420ede453SJeff Dike " UMLs and file locking will be turned off - this is appropriate for a\n" 43520ede453SJeff Dike " cluster filesystem and inappropriate at almost all other times.\n\n" 43650109b5aSAnton Ivanov " 't' will disable trim/discard support on the device (enabled by default).\n\n" 437ef3ba87cSChristopher Obbard " An optional device serial number can be exposed using the serial parameter\n" 438ef3ba87cSChristopher Obbard " on the cmdline which is exposed as a sysfs entry. This is particularly\n" 439ef3ba87cSChristopher Obbard " useful when a unique number should be given to the device. Note when\n" 440ef3ba87cSChristopher Obbard " specifying a label, the filename2 must be also presented. It can be\n" 441ef3ba87cSChristopher Obbard " an empty string, in which case the backing file is not used:\n" 442ef3ba87cSChristopher Obbard " ubd0=File,,Serial\n" 4431da177e4SLinus Torvalds ); 4441da177e4SLinus Torvalds 4458299ca5cSJeff Dike static int udb_setup(char *str) 4461da177e4SLinus Torvalds { 4471da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 4481da177e4SLinus Torvalds "udb TYPO\n", str); 449dc764e50SJeff Dike return 1; 4501da177e4SLinus Torvalds } 4511da177e4SLinus Torvalds 4521da177e4SLinus Torvalds __setup("udb", udb_setup); 4531da177e4SLinus Torvalds __uml_help(udb_setup, 4541da177e4SLinus Torvalds "udb\n" 4550894e27eSJeff Dike " This option is here solely to catch ubd -> udb typos, which can be\n" 4560894e27eSJeff Dike " to impossible to catch visually unless you specifically look for\n" 4570894e27eSJeff Dike " them. The only result of any option starting with 'udb' is an error\n" 4581da177e4SLinus Torvalds " in the boot output.\n\n" 4591da177e4SLinus Torvalds ); 4601da177e4SLinus Torvalds 46191acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 4625dc62b1bSWANG Cong static int thread_fd = -1; 46309ace81cSJeff Dike 464f88f0bdfSAnton Ivanov /* Function to read several request pointers at a time 465f88f0bdfSAnton Ivanov * handling fractional reads if (and as) needed 466f88f0bdfSAnton Ivanov */ 467f88f0bdfSAnton Ivanov 468f88f0bdfSAnton Ivanov static int bulk_req_safe_read( 469f88f0bdfSAnton Ivanov int fd, 470f88f0bdfSAnton Ivanov struct io_thread_req * (*request_buffer)[], 471f88f0bdfSAnton Ivanov struct io_thread_req **remainder, 472f88f0bdfSAnton Ivanov int *remainder_size, 473f88f0bdfSAnton Ivanov int max_recs 474f88f0bdfSAnton Ivanov ) 475f88f0bdfSAnton Ivanov { 476f88f0bdfSAnton Ivanov int n = 0; 477f88f0bdfSAnton Ivanov int res = 0; 478f88f0bdfSAnton Ivanov 479f88f0bdfSAnton Ivanov if (*remainder_size > 0) { 480f88f0bdfSAnton Ivanov memmove( 481f88f0bdfSAnton Ivanov (char *) request_buffer, 482f88f0bdfSAnton Ivanov (char *) remainder, *remainder_size 483f88f0bdfSAnton Ivanov ); 484f88f0bdfSAnton Ivanov n = *remainder_size; 485f88f0bdfSAnton Ivanov } 486f88f0bdfSAnton Ivanov 487f88f0bdfSAnton Ivanov res = os_read_file( 488f88f0bdfSAnton Ivanov fd, 489f88f0bdfSAnton Ivanov ((char *) request_buffer) + *remainder_size, 490f88f0bdfSAnton Ivanov sizeof(struct io_thread_req *)*max_recs 491f88f0bdfSAnton Ivanov - *remainder_size 492f88f0bdfSAnton Ivanov ); 493f88f0bdfSAnton Ivanov if (res > 0) { 494f88f0bdfSAnton Ivanov n += res; 495f88f0bdfSAnton Ivanov if ((n % sizeof(struct io_thread_req *)) > 0) { 496f88f0bdfSAnton Ivanov /* 497f88f0bdfSAnton Ivanov * Read somehow returned not a multiple of dword 498f88f0bdfSAnton Ivanov * theoretically possible, but never observed in the 499f88f0bdfSAnton Ivanov * wild, so read routine must be able to handle it 500f88f0bdfSAnton Ivanov */ 501f88f0bdfSAnton Ivanov *remainder_size = n % sizeof(struct io_thread_req *); 502f88f0bdfSAnton Ivanov WARN(*remainder_size > 0, "UBD IPC read returned a partial result"); 503f88f0bdfSAnton Ivanov memmove( 504f88f0bdfSAnton Ivanov remainder, 505f88f0bdfSAnton Ivanov ((char *) request_buffer) + 506f88f0bdfSAnton Ivanov (n/sizeof(struct io_thread_req *))*sizeof(struct io_thread_req *), 507f88f0bdfSAnton Ivanov *remainder_size 508f88f0bdfSAnton Ivanov ); 509f88f0bdfSAnton Ivanov n = n - *remainder_size; 510f88f0bdfSAnton Ivanov } 511f88f0bdfSAnton Ivanov } else { 512f88f0bdfSAnton Ivanov n = res; 513f88f0bdfSAnton Ivanov } 514f88f0bdfSAnton Ivanov return n; 515f88f0bdfSAnton Ivanov } 516f88f0bdfSAnton Ivanov 51762f96cb0SJeff Dike /* Called without dev->lock held, and only in interrupt context. */ 51891acb21fSJeff Dike static void ubd_handler(void) 51991acb21fSJeff Dike { 52091acb21fSJeff Dike int n; 521f88f0bdfSAnton Ivanov int count; 52209ace81cSJeff Dike 523a0044bdfSJeff Dike while(1){ 524f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 525f88f0bdfSAnton Ivanov thread_fd, 526f88f0bdfSAnton Ivanov irq_req_buffer, 527f88f0bdfSAnton Ivanov &irq_remainder, 528f88f0bdfSAnton Ivanov &irq_remainder_size, 529f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 530f88f0bdfSAnton Ivanov ); 531f88f0bdfSAnton Ivanov if (n < 0) { 532a0044bdfSJeff Dike if(n == -EAGAIN) 533a0044bdfSJeff Dike break; 534a0044bdfSJeff Dike printk(KERN_ERR "spurious interrupt in ubd_handler, " 535a0044bdfSJeff Dike "err = %d\n", -n); 53691acb21fSJeff Dike return; 53791acb21fSJeff Dike } 538f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 5394e6da0feSRichard Weinberger struct io_thread_req *io_req = (*irq_req_buffer)[count]; 540a0044bdfSJeff Dike 54150109b5aSAnton Ivanov if ((io_req->error == BLK_STS_NOTSUPP) && (req_op(io_req->req) == REQ_OP_DISCARD)) { 54250109b5aSAnton Ivanov blk_queue_max_discard_sectors(io_req->req->q, 0); 54350109b5aSAnton Ivanov blk_queue_max_write_zeroes_sectors(io_req->req->q, 0); 54450109b5aSAnton Ivanov blk_queue_flag_clear(QUEUE_FLAG_DISCARD, io_req->req->q); 54550109b5aSAnton Ivanov } 54650109b5aSAnton Ivanov blk_mq_end_request(io_req->req, io_req->error); 5474e6da0feSRichard Weinberger kfree(io_req); 548a0044bdfSJeff Dike } 54991acb21fSJeff Dike } 5504e6da0feSRichard Weinberger } 5514e6da0feSRichard Weinberger 5527bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 5531da177e4SLinus Torvalds { 55491acb21fSJeff Dike ubd_handler(); 555dc764e50SJeff Dike return IRQ_HANDLED; 5561da177e4SLinus Torvalds } 5571da177e4SLinus Torvalds 55891acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 55991acb21fSJeff Dike static int io_pid = -1; 56091acb21fSJeff Dike 5615dc62b1bSWANG Cong static void kill_io_thread(void) 56291acb21fSJeff Dike { 56391acb21fSJeff Dike if(io_pid != -1) 56491acb21fSJeff Dike os_kill_process(io_pid, 1); 56591acb21fSJeff Dike } 56691acb21fSJeff Dike 56791acb21fSJeff Dike __uml_exitcall(kill_io_thread); 56891acb21fSJeff Dike 569d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5701da177e4SLinus Torvalds { 5711da177e4SLinus Torvalds char *file; 57285356398SRichard Weinberger int fd; 57385356398SRichard Weinberger int err; 5741da177e4SLinus Torvalds 57585356398SRichard Weinberger __u32 version; 57685356398SRichard Weinberger __u32 align; 57785356398SRichard Weinberger char *backing_file; 578853bc0abSArnd Bergmann time64_t mtime; 57985356398SRichard Weinberger unsigned long long size; 58085356398SRichard Weinberger int sector_size; 58185356398SRichard Weinberger int bitmap_offset; 58285356398SRichard Weinberger 58385356398SRichard Weinberger if (ubd_dev->file && ubd_dev->cow.file) { 58485356398SRichard Weinberger file = ubd_dev->cow.file; 58585356398SRichard Weinberger 58685356398SRichard Weinberger goto out; 58785356398SRichard Weinberger } 58885356398SRichard Weinberger 589d4afcba9SMartin Pärtel fd = os_open_file(ubd_dev->file, of_read(OPENFLAGS()), 0); 59085356398SRichard Weinberger if (fd < 0) 59185356398SRichard Weinberger return fd; 59285356398SRichard Weinberger 59385356398SRichard Weinberger err = read_cow_header(file_reader, &fd, &version, &backing_file, \ 59485356398SRichard Weinberger &mtime, &size, §or_size, &align, &bitmap_offset); 59585356398SRichard Weinberger os_close_file(fd); 59685356398SRichard Weinberger 59785356398SRichard Weinberger if(err == -EINVAL) 59885356398SRichard Weinberger file = ubd_dev->file; 59985356398SRichard Weinberger else 60085356398SRichard Weinberger file = backing_file; 60185356398SRichard Weinberger 60285356398SRichard Weinberger out: 603dc764e50SJeff Dike return os_file_size(file, size_out); 6041da177e4SLinus Torvalds } 6051da177e4SLinus Torvalds 6065dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 6075dc62b1bSWANG Cong { 6085dc62b1bSWANG Cong int err; 6095dc62b1bSWANG Cong 6108c6157b6SAnton Ivanov err = os_pread_file(fd, buf, len, offset); 6115dc62b1bSWANG Cong if (err < 0) 6125dc62b1bSWANG Cong return err; 6135dc62b1bSWANG Cong 6145dc62b1bSWANG Cong return 0; 6155dc62b1bSWANG Cong } 6165dc62b1bSWANG Cong 617853bc0abSArnd Bergmann static int backing_file_mismatch(char *file, __u64 size, time64_t mtime) 6185dc62b1bSWANG Cong { 619853bc0abSArnd Bergmann time64_t modtime; 6205dc62b1bSWANG Cong unsigned long long actual; 6215dc62b1bSWANG Cong int err; 6225dc62b1bSWANG Cong 6235dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 6245dc62b1bSWANG Cong if (err < 0) { 6255dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 6265dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 6275dc62b1bSWANG Cong return err; 6285dc62b1bSWANG Cong } 6295dc62b1bSWANG Cong 6305dc62b1bSWANG Cong err = os_file_size(file, &actual); 6315dc62b1bSWANG Cong if (err < 0) { 6325dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 6335dc62b1bSWANG Cong "err = %d\n", file, -err); 6345dc62b1bSWANG Cong return err; 6355dc62b1bSWANG Cong } 6365dc62b1bSWANG Cong 6375dc62b1bSWANG Cong if (actual != size) { 6385dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 6395dc62b1bSWANG Cong * the typecast.*/ 6405dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 6415dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 6425dc62b1bSWANG Cong return -EINVAL; 6435dc62b1bSWANG Cong } 6445dc62b1bSWANG Cong if (modtime != mtime) { 645853bc0abSArnd Bergmann printk(KERN_ERR "mtime mismatch (%lld vs %lld) of COW header vs " 6465dc62b1bSWANG Cong "backing file\n", mtime, modtime); 6475dc62b1bSWANG Cong return -EINVAL; 6485dc62b1bSWANG Cong } 6495dc62b1bSWANG Cong return 0; 6505dc62b1bSWANG Cong } 6515dc62b1bSWANG Cong 6525dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 6535dc62b1bSWANG Cong { 6545dc62b1bSWANG Cong struct uml_stat buf1, buf2; 6555dc62b1bSWANG Cong int err; 6565dc62b1bSWANG Cong 6575dc62b1bSWANG Cong if (from_cmdline == NULL) 6585dc62b1bSWANG Cong return 0; 6595dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 6605dc62b1bSWANG Cong return 0; 6615dc62b1bSWANG Cong 6625dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 6635dc62b1bSWANG Cong if (err < 0) { 6645dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 6655dc62b1bSWANG Cong -err); 6665dc62b1bSWANG Cong return 0; 6675dc62b1bSWANG Cong } 6685dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 6695dc62b1bSWANG Cong if (err < 0) { 6705dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 6715dc62b1bSWANG Cong -err); 6725dc62b1bSWANG Cong return 1; 6735dc62b1bSWANG Cong } 6745dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 6755dc62b1bSWANG Cong return 0; 6765dc62b1bSWANG Cong 6775dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 6785dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 6795dc62b1bSWANG Cong from_cmdline, from_cow, cow); 6805dc62b1bSWANG Cong return 1; 6815dc62b1bSWANG Cong } 6825dc62b1bSWANG Cong 6835dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 6845dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 6855dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6865dc62b1bSWANG Cong int *create_cow_out) 6875dc62b1bSWANG Cong { 688853bc0abSArnd Bergmann time64_t mtime; 6895dc62b1bSWANG Cong unsigned long long size; 6905dc62b1bSWANG Cong __u32 version, align; 6915dc62b1bSWANG Cong char *backing_file; 6925dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6935dc62b1bSWANG Cong 6945dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6955dc62b1bSWANG Cong if (fd < 0) { 6965dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6975dc62b1bSWANG Cong *create_cow_out = 1; 6985dc62b1bSWANG Cong if (!openflags->w || 6995dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 7005dc62b1bSWANG Cong return fd; 7015dc62b1bSWANG Cong openflags->w = 0; 7025dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 7035dc62b1bSWANG Cong if (fd < 0) 7045dc62b1bSWANG Cong return fd; 7055dc62b1bSWANG Cong } 7065dc62b1bSWANG Cong 7075dc62b1bSWANG Cong if (shared) 7085dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 7095dc62b1bSWANG Cong else { 7105dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 7115dc62b1bSWANG Cong if (err < 0) { 7125dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 7135dc62b1bSWANG Cong file, -err); 7145dc62b1bSWANG Cong goto out_close; 7155dc62b1bSWANG Cong } 7165dc62b1bSWANG Cong } 7175dc62b1bSWANG Cong 7185dc62b1bSWANG Cong /* Successful return case! */ 7195dc62b1bSWANG Cong if (backing_file_out == NULL) 7205dc62b1bSWANG Cong return fd; 7215dc62b1bSWANG Cong 7225dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 7235dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 7245dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 7255dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 7265dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 7275dc62b1bSWANG Cong goto out_close; 7285dc62b1bSWANG Cong } 7295dc62b1bSWANG Cong if (err) 7305dc62b1bSWANG Cong return fd; 7315dc62b1bSWANG Cong 7325dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 7335dc62b1bSWANG Cong file); 7345dc62b1bSWANG Cong 7355dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 7365dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 7375dc62b1bSWANG Cong mtime)) { 7385dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 7395dc62b1bSWANG Cong *backing_file_out); 7405dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 7415dc62b1bSWANG Cong sectorsize, align, &size); 7425dc62b1bSWANG Cong if (err) { 7435dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 7445dc62b1bSWANG Cong goto out_close; 7455dc62b1bSWANG Cong } 7465dc62b1bSWANG Cong } else { 7475dc62b1bSWANG Cong *backing_file_out = backing_file; 7485dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 7495dc62b1bSWANG Cong if (err) 7505dc62b1bSWANG Cong goto out_close; 7515dc62b1bSWANG Cong } 7525dc62b1bSWANG Cong 7535dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 7545dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 7555dc62b1bSWANG Cong 7565dc62b1bSWANG Cong return fd; 7575dc62b1bSWANG Cong out_close: 7585dc62b1bSWANG Cong os_close_file(fd); 7595dc62b1bSWANG Cong return err; 7605dc62b1bSWANG Cong } 7615dc62b1bSWANG Cong 7625dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 7635dc62b1bSWANG Cong struct openflags flags, 7645dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 7655dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 7665dc62b1bSWANG Cong { 7675dc62b1bSWANG Cong int err, fd; 7685dc62b1bSWANG Cong 7695dc62b1bSWANG Cong flags.c = 1; 7705dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 7715dc62b1bSWANG Cong if (fd < 0) { 7725dc62b1bSWANG Cong err = fd; 7735dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 7745dc62b1bSWANG Cong cow_file, -err); 7755dc62b1bSWANG Cong goto out; 7765dc62b1bSWANG Cong } 7775dc62b1bSWANG Cong 7785dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 7795dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 7805dc62b1bSWANG Cong data_offset_out); 7815dc62b1bSWANG Cong if (!err) 7825dc62b1bSWANG Cong return fd; 7835dc62b1bSWANG Cong os_close_file(fd); 7845dc62b1bSWANG Cong out: 7855dc62b1bSWANG Cong return err; 7865dc62b1bSWANG Cong } 7875dc62b1bSWANG Cong 7885f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7891da177e4SLinus Torvalds { 7907d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7917d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7921da177e4SLinus Torvalds return; 7931da177e4SLinus Torvalds 7947d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7957d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7967d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7971da177e4SLinus Torvalds } 7981da177e4SLinus Torvalds 7997d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 8001da177e4SLinus Torvalds { 8011da177e4SLinus Torvalds struct openflags flags; 8021da177e4SLinus Torvalds char **back_ptr; 8031da177e4SLinus Torvalds int err, create_cow, *create_ptr; 8040bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 8051da177e4SLinus Torvalds 8067d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 8071da177e4SLinus Torvalds create_cow = 0; 8087d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 8097d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 8100bf16bffSPaolo 'Blaisorblade' Giarrusso 8110bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 8127d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 8137d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 8146c29256cSJeff Dike create_ptr); 8151da177e4SLinus Torvalds 8160bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 8170bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 818a43c8316SAnton Ivanov ubd_dev->openflags, SECTOR_SIZE, PAGE_SIZE, 8197d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 8207d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 8217d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 8220bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 8231da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 8247d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 8251da177e4SLinus Torvalds } 8261da177e4SLinus Torvalds } 8271da177e4SLinus Torvalds 8280bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 8297d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 8300bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 8310bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 8321da177e4SLinus Torvalds } 8330bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 8341da177e4SLinus Torvalds 8357d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 836086fa5ffSMartin K. Petersen blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); 837f4768ffdSJeff Dike 8381da177e4SLinus Torvalds err = -ENOMEM; 839da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 8407d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 8411da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 8421da177e4SLinus Torvalds goto error; 8431da177e4SLinus Torvalds } 8441da177e4SLinus Torvalds flush_tlb_kernel_vm(); 8451da177e4SLinus Torvalds 8467d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 8477d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 8487d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 8491da177e4SLinus Torvalds if(err < 0) 8501da177e4SLinus Torvalds goto error; 8511da177e4SLinus Torvalds 8527d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 8531da177e4SLinus Torvalds flags.w = 0; 8547d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 8556c29256cSJeff Dike NULL, NULL, NULL, NULL); 8561da177e4SLinus Torvalds if(err < 0) goto error; 8577d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 8581da177e4SLinus Torvalds } 85950109b5aSAnton Ivanov if (ubd_dev->no_trim == 0) { 86050109b5aSAnton Ivanov ubd_dev->queue->limits.discard_granularity = SECTOR_SIZE; 86150109b5aSAnton Ivanov ubd_dev->queue->limits.discard_alignment = SECTOR_SIZE; 86250109b5aSAnton Ivanov blk_queue_max_discard_sectors(ubd_dev->queue, UBD_MAX_REQUEST); 86350109b5aSAnton Ivanov blk_queue_max_write_zeroes_sectors(ubd_dev->queue, UBD_MAX_REQUEST); 86450109b5aSAnton Ivanov blk_queue_flag_set(QUEUE_FLAG_DISCARD, ubd_dev->queue); 86550109b5aSAnton Ivanov } 866a43c8316SAnton Ivanov blk_queue_flag_set(QUEUE_FLAG_NONROT, ubd_dev->queue); 867dc764e50SJeff Dike return 0; 8681da177e4SLinus Torvalds error: 8697d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 870dc764e50SJeff Dike return err; 8711da177e4SLinus Torvalds } 8721da177e4SLinus Torvalds 8732e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 8742e3f5251SJeff Dike { 8758691b97bSGreg Kroah-Hartman struct ubd *ubd_dev = dev_get_drvdata(dev); 8762e3f5251SJeff Dike 8772e3f5251SJeff Dike blk_cleanup_queue(ubd_dev->queue); 8784e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 8792e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 8802e3f5251SJeff Dike } 8812e3f5251SJeff Dike 882ef3ba87cSChristopher Obbard static ssize_t serial_show(struct device *dev, 883ef3ba87cSChristopher Obbard struct device_attribute *attr, char *buf) 884ef3ba87cSChristopher Obbard { 885ef3ba87cSChristopher Obbard struct gendisk *disk = dev_to_disk(dev); 886ef3ba87cSChristopher Obbard struct ubd *ubd_dev = disk->private_data; 887ef3ba87cSChristopher Obbard 888ef3ba87cSChristopher Obbard if (!ubd_dev) 889ef3ba87cSChristopher Obbard return 0; 890ef3ba87cSChristopher Obbard 891ef3ba87cSChristopher Obbard return sprintf(buf, "%s", ubd_dev->serial); 892ef3ba87cSChristopher Obbard } 893ef3ba87cSChristopher Obbard 894ef3ba87cSChristopher Obbard static DEVICE_ATTR_RO(serial); 895ef3ba87cSChristopher Obbard 896ef3ba87cSChristopher Obbard static struct attribute *ubd_attrs[] = { 897ef3ba87cSChristopher Obbard &dev_attr_serial.attr, 898ef3ba87cSChristopher Obbard NULL, 899ef3ba87cSChristopher Obbard }; 900ef3ba87cSChristopher Obbard 901ef3ba87cSChristopher Obbard static umode_t ubd_attrs_are_visible(struct kobject *kobj, 902ef3ba87cSChristopher Obbard struct attribute *a, int n) 903ef3ba87cSChristopher Obbard { 904ef3ba87cSChristopher Obbard return a->mode; 905ef3ba87cSChristopher Obbard } 906ef3ba87cSChristopher Obbard 907ef3ba87cSChristopher Obbard static const struct attribute_group ubd_attr_group = { 908ef3ba87cSChristopher Obbard .attrs = ubd_attrs, 909ef3ba87cSChristopher Obbard .is_visible = ubd_attrs_are_visible, 910ef3ba87cSChristopher Obbard }; 911ef3ba87cSChristopher Obbard 912ef3ba87cSChristopher Obbard static const struct attribute_group *ubd_attr_groups[] = { 913ef3ba87cSChristopher Obbard &ubd_attr_group, 914ef3ba87cSChristopher Obbard NULL, 915ef3ba87cSChristopher Obbard }; 916ef3ba87cSChristopher Obbard 9175f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 9181da177e4SLinus Torvalds struct gendisk **disk_out) 9191da177e4SLinus Torvalds { 920d72a5783SDan Williams struct device *parent = NULL; 9211da177e4SLinus Torvalds struct gendisk *disk; 9221da177e4SLinus Torvalds 9231da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 9241da177e4SLinus Torvalds if(disk == NULL) 925dc764e50SJeff Dike return -ENOMEM; 9261da177e4SLinus Torvalds 9271da177e4SLinus Torvalds disk->major = major; 9281da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 9291da177e4SLinus Torvalds disk->fops = &ubd_blops; 9301da177e4SLinus Torvalds set_capacity(disk, size / 512); 931792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) 9321da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 933ce7b0f46SGreg Kroah-Hartman else 9341da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 9351da177e4SLinus Torvalds 9361da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 937792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) { 9387d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 9397d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 9402e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 9418691b97bSGreg Kroah-Hartman dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); 9427d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 943d72a5783SDan Williams parent = &ubd_devs[unit].pdev.dev; 9441da177e4SLinus Torvalds } 9451da177e4SLinus Torvalds 9467d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 94762f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 948ef3ba87cSChristopher Obbard device_add_disk(parent, disk, ubd_attr_groups); 9491da177e4SLinus Torvalds 9501da177e4SLinus Torvalds *disk_out = disk; 9511da177e4SLinus Torvalds return 0; 9521da177e4SLinus Torvalds } 9531da177e4SLinus Torvalds 954a43c8316SAnton Ivanov #define ROUND_BLOCK(n) ((n + (SECTOR_SIZE - 1)) & (-SECTOR_SIZE)) 9551da177e4SLinus Torvalds 9564e6da0feSRichard Weinberger static const struct blk_mq_ops ubd_mq_ops = { 9574e6da0feSRichard Weinberger .queue_rq = ubd_queue_rq, 9584e6da0feSRichard Weinberger }; 9594e6da0feSRichard Weinberger 960f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 9611da177e4SLinus Torvalds { 9627d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 963f28169d2SJeff Dike int err = 0; 9641da177e4SLinus Torvalds 9657d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 966ec7cf783SJeff Dike goto out; 9671da177e4SLinus Torvalds 9687d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 969f28169d2SJeff Dike if(err < 0){ 970f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 97180c13749SJeff Dike goto out; 972f28169d2SJeff Dike } 9731da177e4SLinus Torvalds 9747d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 9751da177e4SLinus Torvalds 9764e6da0feSRichard Weinberger ubd_dev->tag_set.ops = &ubd_mq_ops; 9774e6da0feSRichard Weinberger ubd_dev->tag_set.queue_depth = 64; 9784e6da0feSRichard Weinberger ubd_dev->tag_set.numa_node = NUMA_NO_NODE; 9794e6da0feSRichard Weinberger ubd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; 9804e6da0feSRichard Weinberger ubd_dev->tag_set.driver_data = ubd_dev; 9814e6da0feSRichard Weinberger ubd_dev->tag_set.nr_hw_queues = 1; 982a0044bdfSJeff Dike 9834e6da0feSRichard Weinberger err = blk_mq_alloc_tag_set(&ubd_dev->tag_set); 9844e6da0feSRichard Weinberger if (err) 98580c13749SJeff Dike goto out; 9864e6da0feSRichard Weinberger 9874e6da0feSRichard Weinberger ubd_dev->queue = blk_mq_init_queue(&ubd_dev->tag_set); 9884e6da0feSRichard Weinberger if (IS_ERR(ubd_dev->queue)) { 9894e6da0feSRichard Weinberger err = PTR_ERR(ubd_dev->queue); 990aea05eb5SAnton Ivanov goto out_cleanup_tags; 99162f96cb0SJeff Dike } 9924e6da0feSRichard Weinberger 99362f96cb0SJeff Dike ubd_dev->queue->queuedata = ubd_dev; 994f935a8ceSJens Axboe blk_queue_write_cache(ubd_dev->queue, true, false); 99562f96cb0SJeff Dike 9968a78362cSMartin K. Petersen blk_queue_max_segments(ubd_dev->queue, MAX_SG); 997fc6b6a87SGabriel Krisman Bertazi blk_queue_segment_boundary(ubd_dev->queue, PAGE_SIZE - 1); 998792dd4fcSChristoph Hellwig err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); 99962f96cb0SJeff Dike if(err){ 100062f96cb0SJeff Dike *error_out = "Failed to register device"; 10014e6da0feSRichard Weinberger goto out_cleanup_tags; 100262f96cb0SJeff Dike } 10031da177e4SLinus Torvalds 1004792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) 10055f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 10061da177e4SLinus Torvalds &fake_gendisk[n]); 10071da177e4SLinus Torvalds 100883380cc1SJeff Dike /* 100983380cc1SJeff Dike * Perhaps this should also be under the "if (fake_major)" above 101083380cc1SJeff Dike * using the fake_disk->disk_name 101183380cc1SJeff Dike */ 10121da177e4SLinus Torvalds if (fake_ide) 10131da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 10141da177e4SLinus Torvalds 1015ec7cf783SJeff Dike err = 0; 1016ec7cf783SJeff Dike out: 1017ec7cf783SJeff Dike return err; 101862f96cb0SJeff Dike 10194e6da0feSRichard Weinberger out_cleanup_tags: 10204e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 1021aea05eb5SAnton Ivanov if (!(IS_ERR(ubd_dev->queue))) 102262f96cb0SJeff Dike blk_cleanup_queue(ubd_dev->queue); 102362f96cb0SJeff Dike goto out; 10241da177e4SLinus Torvalds } 10251da177e4SLinus Torvalds 1026f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 10271da177e4SLinus Torvalds { 1028e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 10291da177e4SLinus Torvalds 1030f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 1031f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 1032f28169d2SJeff Dike * were set. 1033f28169d2SJeff Dike */ 1034970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 10351da177e4SLinus Torvalds if (str == NULL) { 1036f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 1037f28169d2SJeff Dike return -ENOMEM; 10381da177e4SLinus Torvalds } 1039f28169d2SJeff Dike 1040f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 1041f28169d2SJeff Dike if (ret) 1042e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 1043f28169d2SJeff Dike 1044e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 1045e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 1046d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 1047e7f6552fSPaolo 'Blaisorblade' Giarrusso } 10481da177e4SLinus Torvalds 1049d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 1050f28169d2SJeff Dike ret = ubd_add(n, error_out); 1051e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 10527d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 1053d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 10541da177e4SLinus Torvalds 1055e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 1056e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 1057e7f6552fSPaolo 'Blaisorblade' Giarrusso 1058e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 1059e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 1060e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 10611da177e4SLinus Torvalds } 10621da177e4SLinus Torvalds 10631da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 10641da177e4SLinus Torvalds { 10657d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 10661da177e4SLinus Torvalds int n, len = 0; 10671da177e4SLinus Torvalds 10681da177e4SLinus Torvalds n = parse_unit(&name); 10691da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 10701da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 1071dc764e50SJeff Dike return -1; 10721da177e4SLinus Torvalds } 10731da177e4SLinus Torvalds 10747d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 1075d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10761da177e4SLinus Torvalds 10777d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 10781da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 10791da177e4SLinus Torvalds goto out; 10801da177e4SLinus Torvalds } 10811da177e4SLinus Torvalds 10827d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 10831da177e4SLinus Torvalds 10847d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 10851da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 10867d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 10871da177e4SLinus Torvalds } 10881da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 10891da177e4SLinus Torvalds 10901da177e4SLinus Torvalds out: 1091d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 1092dc764e50SJeff Dike return len; 10931da177e4SLinus Torvalds } 10941da177e4SLinus Torvalds 109529d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 109629d56cfeSJeff Dike { 109729d56cfeSJeff Dike int n; 109829d56cfeSJeff Dike 109929d56cfeSJeff Dike n = parse_unit(str); 110029d56cfeSJeff Dike *start_out = 0; 110129d56cfeSJeff Dike *end_out = MAX_DEV - 1; 110229d56cfeSJeff Dike return n; 110329d56cfeSJeff Dike } 110429d56cfeSJeff Dike 1105f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 11061da177e4SLinus Torvalds { 11072e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 11087d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 110929d56cfeSJeff Dike int err = -ENODEV; 11101da177e4SLinus Torvalds 1111d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 11121da177e4SLinus Torvalds 11137d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 111429d56cfeSJeff Dike 11157d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 111629d56cfeSJeff Dike goto out; 111729d56cfeSJeff Dike 111829d56cfeSJeff Dike /* you cannot remove a open disk */ 111929d56cfeSJeff Dike err = -EBUSY; 11207d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 112129d56cfeSJeff Dike goto out; 112229d56cfeSJeff Dike 11231da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 1124b47d2debSJeff Dike if(disk != NULL){ 1125b47d2debSJeff Dike del_gendisk(disk); 1126b47d2debSJeff Dike put_disk(disk); 1127b47d2debSJeff Dike } 11281da177e4SLinus Torvalds 11291da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 11301da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 11311da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 11321da177e4SLinus Torvalds fake_gendisk[n] = NULL; 11331da177e4SLinus Torvalds } 11341da177e4SLinus Torvalds 11351da177e4SLinus Torvalds err = 0; 11362e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 11371da177e4SLinus Torvalds out: 1138d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 113929d56cfeSJeff Dike return err; 11401da177e4SLinus Torvalds } 11411da177e4SLinus Torvalds 1142f28169d2SJeff Dike /* All these are called by mconsole in process context and without 1143b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 1144f28169d2SJeff Dike */ 11451da177e4SLinus Torvalds static struct mc_device ubd_mc = { 114684f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 11471da177e4SLinus Torvalds .name = "ubd", 11481da177e4SLinus Torvalds .config = ubd_config, 11491da177e4SLinus Torvalds .get_config = ubd_get_config, 115029d56cfeSJeff Dike .id = ubd_id, 11511da177e4SLinus Torvalds .remove = ubd_remove, 11521da177e4SLinus Torvalds }; 11531da177e4SLinus Torvalds 1154d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 11551da177e4SLinus Torvalds { 11561da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 11571da177e4SLinus Torvalds return 0; 11581da177e4SLinus Torvalds } 11591da177e4SLinus Torvalds 11601da177e4SLinus Torvalds __initcall(ubd_mc_init); 11611da177e4SLinus Torvalds 1162d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1163d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1164d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1165d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1166b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1167d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1168d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1169b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1170b8831a1dSJeff Dike 1171dc764e50SJeff Dike return 0; 1172d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1173d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1174d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1175d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1176b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 11773ae5eaecSRussell King static struct platform_driver ubd_driver = { 11783ae5eaecSRussell King .driver = { 11791da177e4SLinus Torvalds .name = DRIVER_NAME, 11803ae5eaecSRussell King }, 11811da177e4SLinus Torvalds }; 11821da177e4SLinus Torvalds 1183d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 11841da177e4SLinus Torvalds { 1185f28169d2SJeff Dike char *error; 1186f28169d2SJeff Dike int i, err; 11871da177e4SLinus Torvalds 1188792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 11891da177e4SLinus Torvalds return -1; 11901da177e4SLinus Torvalds 1191792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 11921da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 11931da177e4SLinus Torvalds 11941da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 11951da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 11961da177e4SLinus Torvalds return -1; 11971da177e4SLinus Torvalds } 1198f88f0bdfSAnton Ivanov 11996da2ec56SKees Cook irq_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 12006da2ec56SKees Cook sizeof(struct io_thread_req *), 1201f88f0bdfSAnton Ivanov GFP_KERNEL 1202f88f0bdfSAnton Ivanov ); 1203f88f0bdfSAnton Ivanov irq_remainder = 0; 1204f88f0bdfSAnton Ivanov 1205f88f0bdfSAnton Ivanov if (irq_req_buffer == NULL) { 1206f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1207f88f0bdfSAnton Ivanov return -1; 1208f88f0bdfSAnton Ivanov } 12096da2ec56SKees Cook io_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 12106da2ec56SKees Cook sizeof(struct io_thread_req *), 1211f88f0bdfSAnton Ivanov GFP_KERNEL 1212f88f0bdfSAnton Ivanov ); 1213f88f0bdfSAnton Ivanov 1214f88f0bdfSAnton Ivanov io_remainder = 0; 1215f88f0bdfSAnton Ivanov 1216f88f0bdfSAnton Ivanov if (io_req_buffer == NULL) { 1217f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1218f88f0bdfSAnton Ivanov return -1; 1219f88f0bdfSAnton Ivanov } 12203ae5eaecSRussell King platform_driver_register(&ubd_driver); 1221b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1222f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1223f28169d2SJeff Dike err = ubd_add(i, &error); 1224f28169d2SJeff Dike if(err) 1225f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1226f28169d2SJeff Dike "%s\n", i, error); 1227f28169d2SJeff Dike } 1228b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 12291da177e4SLinus Torvalds return 0; 12301da177e4SLinus Torvalds } 12311da177e4SLinus Torvalds 12321da177e4SLinus Torvalds late_initcall(ubd_init); 12331da177e4SLinus Torvalds 1234d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 123591acb21fSJeff Dike unsigned long stack; 123691acb21fSJeff Dike int err; 123791acb21fSJeff Dike 123891acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 123991acb21fSJeff Dike if(global_openflags.s){ 124091acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 124191acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 124291acb21fSJeff Dike * enough. So use anyway the io thread. */ 124391acb21fSJeff Dike } 1244ef4459a6SJohannes Berg stack = alloc_stack(0); 124591acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 124691acb21fSJeff Dike &thread_fd); 124791acb21fSJeff Dike if(io_pid < 0){ 124891acb21fSJeff Dike printk(KERN_ERR 124991acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 125091acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 125191acb21fSJeff Dike io_pid = -1; 1252dc764e50SJeff Dike return 0; 125391acb21fSJeff Dike } 125491acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 1255c0b79a90SYong Zhang 0, "ubd", ubd_devs); 125636d46a59SJohannes Berg if(err < 0) 125791acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1258f4c57a78SJeff Dike return 0; 125991acb21fSJeff Dike } 126091acb21fSJeff Dike 126191acb21fSJeff Dike device_initcall(ubd_driver_init); 126291acb21fSJeff Dike 1263a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 12641da177e4SLinus Torvalds { 1265a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 12667d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12671da177e4SLinus Torvalds int err = 0; 12681da177e4SLinus Torvalds 12699a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12707d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 12717d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 12721da177e4SLinus Torvalds if(err){ 12731da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 12747d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 12751da177e4SLinus Torvalds goto out; 12761da177e4SLinus Torvalds } 12771da177e4SLinus Torvalds } 12787d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 12797d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 12802c49be99SPaolo 'Blaisorblade' Giarrusso 12812c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 12822c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1283a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 12845f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 12851da177e4SLinus Torvalds err = -EROFS; 12862c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 12871da177e4SLinus Torvalds out: 12889a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 1289dc764e50SJeff Dike return err; 12901da177e4SLinus Torvalds } 12911da177e4SLinus Torvalds 1292db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode) 12931da177e4SLinus Torvalds { 12947d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12951da177e4SLinus Torvalds 12969a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12977d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 12985f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 12999a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 13001da177e4SLinus Torvalds } 13011da177e4SLinus Torvalds 130291acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 130391acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 130491acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 130591acb21fSJeff Dike __u64 bitmap_len) 13061da177e4SLinus Torvalds { 1307a43c8316SAnton Ivanov __u64 sector = io_offset >> SECTOR_SHIFT; 130891acb21fSJeff Dike int i, update_bitmap = 0; 13091da177e4SLinus Torvalds 1310a43c8316SAnton Ivanov for (i = 0; i < length >> SECTOR_SHIFT; i++) { 131191acb21fSJeff Dike if(cow_mask != NULL) 131291acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 131391acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 131409ace81cSJeff Dike continue; 13151da177e4SLinus Torvalds 131691acb21fSJeff Dike update_bitmap = 1; 131791acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 13181da177e4SLinus Torvalds } 131991acb21fSJeff Dike 132091acb21fSJeff Dike if(!update_bitmap) 132191acb21fSJeff Dike return; 132291acb21fSJeff Dike 132391acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 132491acb21fSJeff Dike 132591acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 132691acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 132791acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 132891acb21fSJeff Dike * for the original diagnosis. 132991acb21fSJeff Dike */ 13306d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 13316d074242SJiri Olsa sizeof(unsigned long)) - 1)) 133291acb21fSJeff Dike (*cow_offset)--; 133391acb21fSJeff Dike 133491acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 133591acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 133691acb21fSJeff Dike 133791acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 133891acb21fSJeff Dike *cow_offset += bitmap_offset; 133991acb21fSJeff Dike } 134091acb21fSJeff Dike 1341fc6b6a87SGabriel Krisman Bertazi static void cowify_req(struct io_thread_req *req, struct io_desc *segment, 1342fc6b6a87SGabriel Krisman Bertazi unsigned long offset, unsigned long *bitmap, 134391acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 134491acb21fSJeff Dike { 1345fc6b6a87SGabriel Krisman Bertazi __u64 sector = offset >> SECTOR_SHIFT; 134691acb21fSJeff Dike int i; 134791acb21fSJeff Dike 1348fc6b6a87SGabriel Krisman Bertazi if (segment->length > (sizeof(segment->sector_mask) * 8) << SECTOR_SHIFT) 134991acb21fSJeff Dike panic("Operation too long"); 135091acb21fSJeff Dike 1351a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_READ) { 1352fc6b6a87SGabriel Krisman Bertazi for (i = 0; i < segment->length >> SECTOR_SHIFT; i++) { 135391acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 135491acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 1355fc6b6a87SGabriel Krisman Bertazi &segment->sector_mask); 135691acb21fSJeff Dike } 1357fc6b6a87SGabriel Krisman Bertazi } else { 1358fc6b6a87SGabriel Krisman Bertazi cowify_bitmap(offset, segment->length, &segment->sector_mask, 1359fc6b6a87SGabriel Krisman Bertazi &segment->cow_offset, bitmap, bitmap_offset, 1360fc6b6a87SGabriel Krisman Bertazi segment->bitmap_words, bitmap_len); 136191acb21fSJeff Dike } 13621da177e4SLinus Torvalds } 13631da177e4SLinus Torvalds 1364fc6b6a87SGabriel Krisman Bertazi static void ubd_map_req(struct ubd *dev, struct io_thread_req *io_req, 1365fc6b6a87SGabriel Krisman Bertazi struct request *req) 13661da177e4SLinus Torvalds { 1367fc6b6a87SGabriel Krisman Bertazi struct bio_vec bvec; 1368fc6b6a87SGabriel Krisman Bertazi struct req_iterator iter; 1369fc6b6a87SGabriel Krisman Bertazi int i = 0; 1370fc6b6a87SGabriel Krisman Bertazi unsigned long byte_offset = io_req->offset; 1371fc6b6a87SGabriel Krisman Bertazi int op = req_op(req); 1372ecb0a83eSChristoph Hellwig 1373fc6b6a87SGabriel Krisman Bertazi if (op == REQ_OP_WRITE_ZEROES || op == REQ_OP_DISCARD) { 1374fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[0].buffer = NULL; 1375fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[0].length = blk_rq_bytes(req); 1376fc6b6a87SGabriel Krisman Bertazi } else { 1377fc6b6a87SGabriel Krisman Bertazi rq_for_each_segment(bvec, req, iter) { 1378fc6b6a87SGabriel Krisman Bertazi BUG_ON(i >= io_req->desc_cnt); 1379fc6b6a87SGabriel Krisman Bertazi 1380fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].buffer = 1381fc6b6a87SGabriel Krisman Bertazi page_address(bvec.bv_page) + bvec.bv_offset; 1382fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].length = bvec.bv_len; 1383fc6b6a87SGabriel Krisman Bertazi i++; 1384fc6b6a87SGabriel Krisman Bertazi } 1385fc6b6a87SGabriel Krisman Bertazi } 1386fc6b6a87SGabriel Krisman Bertazi 1387fc6b6a87SGabriel Krisman Bertazi if (dev->cow.file) { 1388fc6b6a87SGabriel Krisman Bertazi for (i = 0; i < io_req->desc_cnt; i++) { 1389fc6b6a87SGabriel Krisman Bertazi cowify_req(io_req, &io_req->io_desc[i], byte_offset, 1390fc6b6a87SGabriel Krisman Bertazi dev->cow.bitmap, dev->cow.bitmap_offset, 1391fc6b6a87SGabriel Krisman Bertazi dev->cow.bitmap_len); 1392fc6b6a87SGabriel Krisman Bertazi byte_offset += io_req->io_desc[i].length; 1393fc6b6a87SGabriel Krisman Bertazi } 1394fc6b6a87SGabriel Krisman Bertazi 1395fc6b6a87SGabriel Krisman Bertazi } 1396fc6b6a87SGabriel Krisman Bertazi } 1397fc6b6a87SGabriel Krisman Bertazi 1398fc6b6a87SGabriel Krisman Bertazi static struct io_thread_req *ubd_alloc_req(struct ubd *dev, struct request *req, 1399fc6b6a87SGabriel Krisman Bertazi int desc_cnt) 1400fc6b6a87SGabriel Krisman Bertazi { 1401fc6b6a87SGabriel Krisman Bertazi struct io_thread_req *io_req; 1402fc6b6a87SGabriel Krisman Bertazi int i; 1403fc6b6a87SGabriel Krisman Bertazi 1404fc6b6a87SGabriel Krisman Bertazi io_req = kmalloc(sizeof(*io_req) + 1405fc6b6a87SGabriel Krisman Bertazi (desc_cnt * sizeof(struct io_desc)), 1406fc6b6a87SGabriel Krisman Bertazi GFP_ATOMIC); 1407ecb0a83eSChristoph Hellwig if (!io_req) 1408fc6b6a87SGabriel Krisman Bertazi return NULL; 140991acb21fSJeff Dike 141062f96cb0SJeff Dike io_req->req = req; 1411ecb0a83eSChristoph Hellwig if (dev->cow.file) 1412ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->cow.fd; 1413ecb0a83eSChristoph Hellwig else 1414ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->fd; 14150033dfd9SAnton Ivanov io_req->error = 0; 141653766defSAnton Ivanov io_req->sectorsize = SECTOR_SIZE; 1417ecb0a83eSChristoph Hellwig io_req->fds[1] = dev->fd; 1418fc6b6a87SGabriel Krisman Bertazi io_req->offset = (u64) blk_rq_pos(req) << SECTOR_SHIFT; 14191da177e4SLinus Torvalds io_req->offsets[0] = 0; 1420ecb0a83eSChristoph Hellwig io_req->offsets[1] = dev->cow.data_offset; 14211da177e4SLinus Torvalds 1422fc6b6a87SGabriel Krisman Bertazi for (i = 0 ; i < desc_cnt; i++) { 1423fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].sector_mask = 0; 1424fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].cow_offset = -1; 1425fc6b6a87SGabriel Krisman Bertazi } 1426fc6b6a87SGabriel Krisman Bertazi 1427fc6b6a87SGabriel Krisman Bertazi return io_req; 1428fc6b6a87SGabriel Krisman Bertazi } 1429fc6b6a87SGabriel Krisman Bertazi 1430fc6b6a87SGabriel Krisman Bertazi static int ubd_submit_request(struct ubd *dev, struct request *req) 1431fc6b6a87SGabriel Krisman Bertazi { 1432fc6b6a87SGabriel Krisman Bertazi int segs = 0; 1433fc6b6a87SGabriel Krisman Bertazi struct io_thread_req *io_req; 1434fc6b6a87SGabriel Krisman Bertazi int ret; 1435fc6b6a87SGabriel Krisman Bertazi int op = req_op(req); 1436fc6b6a87SGabriel Krisman Bertazi 1437fc6b6a87SGabriel Krisman Bertazi if (op == REQ_OP_FLUSH) 1438fc6b6a87SGabriel Krisman Bertazi segs = 0; 1439fc6b6a87SGabriel Krisman Bertazi else if (op == REQ_OP_WRITE_ZEROES || op == REQ_OP_DISCARD) 1440fc6b6a87SGabriel Krisman Bertazi segs = 1; 1441fc6b6a87SGabriel Krisman Bertazi else 1442fc6b6a87SGabriel Krisman Bertazi segs = blk_rq_nr_phys_segments(req); 1443fc6b6a87SGabriel Krisman Bertazi 1444fc6b6a87SGabriel Krisman Bertazi io_req = ubd_alloc_req(dev, req, segs); 1445fc6b6a87SGabriel Krisman Bertazi if (!io_req) 1446fc6b6a87SGabriel Krisman Bertazi return -ENOMEM; 1447fc6b6a87SGabriel Krisman Bertazi 1448fc6b6a87SGabriel Krisman Bertazi io_req->desc_cnt = segs; 1449fc6b6a87SGabriel Krisman Bertazi if (segs) 1450fc6b6a87SGabriel Krisman Bertazi ubd_map_req(dev, io_req, req); 14511da177e4SLinus Torvalds 1452ecb0a83eSChristoph Hellwig ret = os_write_file(thread_fd, &io_req, sizeof(io_req)); 1453ecb0a83eSChristoph Hellwig if (ret != sizeof(io_req)) { 1454ecb0a83eSChristoph Hellwig if (ret != -EAGAIN) 1455ecb0a83eSChristoph Hellwig pr_err("write to io thread failed: %d\n", -ret); 1456bc1d72e7SRichard Weinberger kfree(io_req); 1457bc1d72e7SRichard Weinberger } 1458ecb0a83eSChristoph Hellwig return ret; 1459bc1d72e7SRichard Weinberger } 1460bc1d72e7SRichard Weinberger 14614e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 14624e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd) 14631da177e4SLinus Torvalds { 14646961cd4dSJens Axboe struct ubd *ubd_dev = hctx->queue->queuedata; 14654e6da0feSRichard Weinberger struct request *req = bd->rq; 146653766defSAnton Ivanov int ret = 0, res = BLK_STS_OK; 14671da177e4SLinus Torvalds 14684e6da0feSRichard Weinberger blk_mq_start_request(req); 1469a0044bdfSJeff Dike 14706961cd4dSJens Axboe spin_lock_irq(&ubd_dev->lock); 14716961cd4dSJens Axboe 147253766defSAnton Ivanov switch (req_op(req)) { 147353766defSAnton Ivanov case REQ_OP_FLUSH: 147453766defSAnton Ivanov case REQ_OP_READ: 147553766defSAnton Ivanov case REQ_OP_WRITE: 147650109b5aSAnton Ivanov case REQ_OP_DISCARD: 147750109b5aSAnton Ivanov case REQ_OP_WRITE_ZEROES: 1478fc6b6a87SGabriel Krisman Bertazi ret = ubd_submit_request(ubd_dev, req); 147950109b5aSAnton Ivanov break; 148053766defSAnton Ivanov default: 148153766defSAnton Ivanov WARN_ON_ONCE(1); 148253766defSAnton Ivanov res = BLK_STS_NOTSUPP; 148353766defSAnton Ivanov } 1484ecb0a83eSChristoph Hellwig 14856961cd4dSJens Axboe spin_unlock_irq(&ubd_dev->lock); 14866961cd4dSJens Axboe 1487d848074bSAnton Ivanov if (ret < 0) { 1488d848074bSAnton Ivanov if (ret == -ENOMEM) 1489d848074bSAnton Ivanov res = BLK_STS_RESOURCE; 1490d848074bSAnton Ivanov else 1491d848074bSAnton Ivanov res = BLK_STS_DEV_RESOURCE; 1492d848074bSAnton Ivanov } 14936961cd4dSJens Axboe 149453766defSAnton Ivanov return res; 149591acb21fSJeff Dike } 14964e6da0feSRichard Weinberger 1497a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1498a885c8c4SChristoph Hellwig { 14997d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1500a885c8c4SChristoph Hellwig 1501a885c8c4SChristoph Hellwig geo->heads = 128; 1502a885c8c4SChristoph Hellwig geo->sectors = 32; 15037d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1504a885c8c4SChristoph Hellwig return 0; 1505a885c8c4SChristoph Hellwig } 1506a885c8c4SChristoph Hellwig 1507a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 15081da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 15091da177e4SLinus Torvalds { 1510a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 151173855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 15121da177e4SLinus Torvalds 15131da177e4SLinus Torvalds switch (cmd) { 15141da177e4SLinus Torvalds struct cdrom_volctrl volume; 15151da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 151673855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 151773855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 151873855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 151973855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 15201da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 15211da177e4SLinus Torvalds sizeof(ubd_id))) 1522dc764e50SJeff Dike return -EFAULT; 1523dc764e50SJeff Dike return 0; 15241da177e4SLinus Torvalds 15251da177e4SLinus Torvalds case CDROMVOLREAD: 15261da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1527dc764e50SJeff Dike return -EFAULT; 15281da177e4SLinus Torvalds volume.channel0 = 255; 15291da177e4SLinus Torvalds volume.channel1 = 255; 15301da177e4SLinus Torvalds volume.channel2 = 255; 15311da177e4SLinus Torvalds volume.channel3 = 255; 15321da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1533dc764e50SJeff Dike return -EFAULT; 1534dc764e50SJeff Dike return 0; 15351da177e4SLinus Torvalds } 1536dc764e50SJeff Dike return -EINVAL; 15371da177e4SLinus Torvalds } 15381da177e4SLinus Torvalds 1539a43c8316SAnton Ivanov static int map_error(int error_code) 1540a43c8316SAnton Ivanov { 1541a43c8316SAnton Ivanov switch (error_code) { 1542a43c8316SAnton Ivanov case 0: 1543a43c8316SAnton Ivanov return BLK_STS_OK; 1544a43c8316SAnton Ivanov case ENOSYS: 1545a43c8316SAnton Ivanov case EOPNOTSUPP: 1546a43c8316SAnton Ivanov return BLK_STS_NOTSUPP; 1547a43c8316SAnton Ivanov case ENOSPC: 1548a43c8316SAnton Ivanov return BLK_STS_NOSPC; 1549a43c8316SAnton Ivanov } 1550a43c8316SAnton Ivanov return BLK_STS_IOERR; 1551a43c8316SAnton Ivanov } 1552a43c8316SAnton Ivanov 1553a41421edSAnton Ivanov /* 1554a41421edSAnton Ivanov * Everything from here onwards *IS NOT PART OF THE KERNEL* 1555a41421edSAnton Ivanov * 1556a41421edSAnton Ivanov * The following functions are part of UML hypervisor code. 1557a41421edSAnton Ivanov * All functions from here onwards are executed as a helper 1558a41421edSAnton Ivanov * thread and are not allowed to execute any kernel functions. 1559a41421edSAnton Ivanov * 1560a41421edSAnton Ivanov * Any communication must occur strictly via shared memory and IPC. 1561a41421edSAnton Ivanov * 1562a41421edSAnton Ivanov * Do not add printks, locks, kernel memory operations, etc - it 1563a41421edSAnton Ivanov * will result in unpredictable behaviour and/or crashes. 1564a41421edSAnton Ivanov */ 1565a41421edSAnton Ivanov 1566fc6b6a87SGabriel Krisman Bertazi static int update_bitmap(struct io_thread_req *req, struct io_desc *segment) 15671da177e4SLinus Torvalds { 156891acb21fSJeff Dike int n; 156991acb21fSJeff Dike 1570fc6b6a87SGabriel Krisman Bertazi if (segment->cow_offset == -1) 1571a43c8316SAnton Ivanov return map_error(0); 157291acb21fSJeff Dike 1573fc6b6a87SGabriel Krisman Bertazi n = os_pwrite_file(req->fds[1], &segment->bitmap_words, 1574fc6b6a87SGabriel Krisman Bertazi sizeof(segment->bitmap_words), segment->cow_offset); 1575fc6b6a87SGabriel Krisman Bertazi if (n != sizeof(segment->bitmap_words)) 1576a43c8316SAnton Ivanov return map_error(-n); 157791acb21fSJeff Dike 1578a43c8316SAnton Ivanov return map_error(0); 157991acb21fSJeff Dike } 158091acb21fSJeff Dike 1581fc6b6a87SGabriel Krisman Bertazi static void do_io(struct io_thread_req *req, struct io_desc *desc) 158291acb21fSJeff Dike { 158350109b5aSAnton Ivanov char *buf = NULL; 158491acb21fSJeff Dike unsigned long len; 158591acb21fSJeff Dike int n, nsectors, start, end, bit; 15861da177e4SLinus Torvalds __u64 off; 15871da177e4SLinus Torvalds 158850109b5aSAnton Ivanov /* FLUSH is really a special case, we cannot "case" it with others */ 158950109b5aSAnton Ivanov 1590a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_FLUSH) { 1591805f11a0SRichard Weinberger /* fds[0] is always either the rw image or our cow file */ 1592a41421edSAnton Ivanov req->error = map_error(-os_sync_file(req->fds[0])); 1593805f11a0SRichard Weinberger return; 1594805f11a0SRichard Weinberger } 1595805f11a0SRichard Weinberger 1596fc6b6a87SGabriel Krisman Bertazi nsectors = desc->length / req->sectorsize; 15971da177e4SLinus Torvalds start = 0; 15981da177e4SLinus Torvalds do { 1599fc6b6a87SGabriel Krisman Bertazi bit = ubd_test_bit(start, (unsigned char *) &desc->sector_mask); 16001da177e4SLinus Torvalds end = start; 16011da177e4SLinus Torvalds while((end < nsectors) && 1602fc6b6a87SGabriel Krisman Bertazi (ubd_test_bit(end, (unsigned char *) &desc->sector_mask) == bit)) 16031da177e4SLinus Torvalds end++; 16041da177e4SLinus Torvalds 160591acb21fSJeff Dike off = req->offset + req->offsets[bit] + 16061da177e4SLinus Torvalds start * req->sectorsize; 16071da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 1608fc6b6a87SGabriel Krisman Bertazi if (desc->buffer != NULL) 1609fc6b6a87SGabriel Krisman Bertazi buf = &desc->buffer[start * req->sectorsize]; 16101da177e4SLinus Torvalds 161150109b5aSAnton Ivanov switch (req_op(req->req)) { 161250109b5aSAnton Ivanov case REQ_OP_READ: 161391acb21fSJeff Dike n = 0; 161491acb21fSJeff Dike do { 161591acb21fSJeff Dike buf = &buf[n]; 161691acb21fSJeff Dike len -= n; 16178c6157b6SAnton Ivanov n = os_pread_file(req->fds[bit], buf, len, off); 161891acb21fSJeff Dike if (n < 0) { 1619a43c8316SAnton Ivanov req->error = map_error(-n); 16201da177e4SLinus Torvalds return; 16211da177e4SLinus Torvalds } 162291acb21fSJeff Dike } while((n < len) && (n != 0)); 162391acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 162450109b5aSAnton Ivanov break; 162550109b5aSAnton Ivanov case REQ_OP_WRITE: 16268c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[bit], buf, len, off); 162791acb21fSJeff Dike if(n != len){ 1628a43c8316SAnton Ivanov req->error = map_error(-n); 162991acb21fSJeff Dike return; 163091acb21fSJeff Dike } 163150109b5aSAnton Ivanov break; 163250109b5aSAnton Ivanov case REQ_OP_DISCARD: 163350109b5aSAnton Ivanov case REQ_OP_WRITE_ZEROES: 163450109b5aSAnton Ivanov n = os_falloc_punch(req->fds[bit], off, len); 163550109b5aSAnton Ivanov if (n) { 163650109b5aSAnton Ivanov req->error = map_error(-n); 163750109b5aSAnton Ivanov return; 163850109b5aSAnton Ivanov } 163950109b5aSAnton Ivanov break; 164050109b5aSAnton Ivanov default: 164150109b5aSAnton Ivanov WARN_ON_ONCE(1); 164250109b5aSAnton Ivanov req->error = BLK_STS_NOTSUPP; 164350109b5aSAnton Ivanov return; 164491acb21fSJeff Dike } 16451da177e4SLinus Torvalds 16461da177e4SLinus Torvalds start = end; 16471da177e4SLinus Torvalds } while(start < nsectors); 164891acb21fSJeff Dike 1649fc6b6a87SGabriel Krisman Bertazi req->offset += len; 1650fc6b6a87SGabriel Krisman Bertazi req->error = update_bitmap(req, desc); 16511da177e4SLinus Torvalds } 165291acb21fSJeff Dike 165391acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 165491acb21fSJeff Dike * from ubd_init, which is an initcall. 165591acb21fSJeff Dike */ 165691acb21fSJeff Dike int kernel_fd = -1; 165791acb21fSJeff Dike 1658d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1659d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 166091acb21fSJeff Dike 166191acb21fSJeff Dike int io_thread(void *arg) 166291acb21fSJeff Dike { 1663f88f0bdfSAnton Ivanov int n, count, written, res; 166491acb21fSJeff Dike 166591d44ff8SRichard Weinberger os_fix_helper_signals(); 166691d44ff8SRichard Weinberger 166791acb21fSJeff Dike while(1){ 1668f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 1669f88f0bdfSAnton Ivanov kernel_fd, 1670f88f0bdfSAnton Ivanov io_req_buffer, 1671f88f0bdfSAnton Ivanov &io_remainder, 1672f88f0bdfSAnton Ivanov &io_remainder_size, 1673f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 1674f88f0bdfSAnton Ivanov ); 1675e355b2f5SGabriel Krisman Bertazi if (n <= 0) { 1676e355b2f5SGabriel Krisman Bertazi if (n == -EAGAIN) 1677f88f0bdfSAnton Ivanov ubd_read_poll(-1); 1678e355b2f5SGabriel Krisman Bertazi 1679f88f0bdfSAnton Ivanov continue; 1680f88f0bdfSAnton Ivanov } 1681f88f0bdfSAnton Ivanov 1682f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 1683fc6b6a87SGabriel Krisman Bertazi struct io_thread_req *req = (*io_req_buffer)[count]; 1684fc6b6a87SGabriel Krisman Bertazi int i; 1685fc6b6a87SGabriel Krisman Bertazi 1686f88f0bdfSAnton Ivanov io_count++; 1687fc6b6a87SGabriel Krisman Bertazi for (i = 0; !req->error && i < req->desc_cnt; i++) 1688fc6b6a87SGabriel Krisman Bertazi do_io(req, &(req->io_desc[i])); 1689fc6b6a87SGabriel Krisman Bertazi 1690f88f0bdfSAnton Ivanov } 1691f88f0bdfSAnton Ivanov 1692f88f0bdfSAnton Ivanov written = 0; 1693f88f0bdfSAnton Ivanov 1694f88f0bdfSAnton Ivanov do { 16956e682d53SGabriel Krisman Bertazi res = os_write_file(kernel_fd, 16966e682d53SGabriel Krisman Bertazi ((char *) io_req_buffer) + written, 16976e682d53SGabriel Krisman Bertazi n - written); 1698ff6a1798SAnton Ivanov if (res >= 0) { 1699f88f0bdfSAnton Ivanov written += res; 170091acb21fSJeff Dike } 1701f88f0bdfSAnton Ivanov if (written < n) { 1702f88f0bdfSAnton Ivanov ubd_write_poll(-1); 1703f88f0bdfSAnton Ivanov } 1704f88f0bdfSAnton Ivanov } while (written < n); 170591acb21fSJeff Dike } 170691acb21fSJeff Dike 17071b57e9c2SJeff Dike return 0; 17081b57e9c2SJeff Dike } 1709