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 50*fc6b6a87SGabriel Krisman Bertazi struct io_desc { 51*fc6b6a87SGabriel Krisman Bertazi char *buffer; 52*fc6b6a87SGabriel Krisman Bertazi unsigned long length; 53*fc6b6a87SGabriel Krisman Bertazi unsigned long sector_mask; 54*fc6b6a87SGabriel Krisman Bertazi unsigned long long cow_offset; 55*fc6b6a87SGabriel Krisman Bertazi unsigned long bitmap_words[2]; 56*fc6b6a87SGabriel Krisman Bertazi }; 57*fc6b6a87SGabriel 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; 65*fc6b6a87SGabriel Krisman Bertazi 66*fc6b6a87SGabriel Krisman Bertazi int desc_cnt; 67*fc6b6a87SGabriel Krisman Bertazi /* io_desc has to be the last element of the struct */ 68*fc6b6a87SGabriel 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; 1581da177e4SLinus Torvalds int count; 1591da177e4SLinus Torvalds int fd; 1601da177e4SLinus Torvalds __u64 size; 1611da177e4SLinus Torvalds struct openflags boot_openflags; 1621da177e4SLinus Torvalds struct openflags openflags; 16384e945e3SPaolo 'Blaisorblade' Giarrusso unsigned shared:1; 16484e945e3SPaolo 'Blaisorblade' Giarrusso unsigned no_cow:1; 16550109b5aSAnton Ivanov unsigned no_trim:1; 1661da177e4SLinus Torvalds struct cow cow; 1671da177e4SLinus Torvalds struct platform_device pdev; 16862f96cb0SJeff Dike struct request_queue *queue; 1694e6da0feSRichard Weinberger struct blk_mq_tag_set tag_set; 17062f96cb0SJeff Dike spinlock_t lock; 1714e6da0feSRichard Weinberger }; 1724e6da0feSRichard Weinberger 1731da177e4SLinus Torvalds #define DEFAULT_COW { \ 1741da177e4SLinus Torvalds .file = NULL, \ 1751da177e4SLinus Torvalds .fd = -1, \ 1761da177e4SLinus Torvalds .bitmap = NULL, \ 1771da177e4SLinus Torvalds .bitmap_offset = 0, \ 1781da177e4SLinus Torvalds .data_offset = 0, \ 1791da177e4SLinus Torvalds } 1801da177e4SLinus Torvalds 1811da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1821da177e4SLinus Torvalds .file = NULL, \ 1831da177e4SLinus Torvalds .count = 0, \ 1841da177e4SLinus Torvalds .fd = -1, \ 1851da177e4SLinus Torvalds .size = -1, \ 1861da177e4SLinus Torvalds .boot_openflags = OPEN_FLAGS, \ 1871da177e4SLinus Torvalds .openflags = OPEN_FLAGS, \ 1881da177e4SLinus Torvalds .no_cow = 0, \ 18950109b5aSAnton Ivanov .no_trim = 0, \ 1906c29256cSJeff Dike .shared = 0, \ 1911da177e4SLinus Torvalds .cow = DEFAULT_COW, \ 19222e65004SThomas Gleixner .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \ 1931da177e4SLinus Torvalds } 1941da177e4SLinus Torvalds 195b8831a1dSJeff Dike /* Protected by ubd_lock */ 1965dc62b1bSWANG Cong static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; 1971da177e4SLinus Torvalds 1981da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 1991da177e4SLinus Torvalds static int fake_ide = 0; 2001da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 2011da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 2021da177e4SLinus Torvalds 2034e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 2044e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd); 2054e6da0feSRichard Weinberger 2061da177e4SLinus Torvalds static void make_proc_ide(void) 2071da177e4SLinus Torvalds { 2081da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 2091da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 2101da177e4SLinus Torvalds } 2111da177e4SLinus Torvalds 2126613c5e8SAlexey Dobriyan static int fake_ide_media_proc_show(struct seq_file *m, void *v) 2131da177e4SLinus Torvalds { 2146613c5e8SAlexey Dobriyan seq_puts(m, "disk\n"); 2156613c5e8SAlexey Dobriyan return 0; 2166613c5e8SAlexey Dobriyan } 2171da177e4SLinus Torvalds 218c0a9290eSWANG Cong static void make_ide_entries(const char *dev_name) 2191da177e4SLinus Torvalds { 2201da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2211da177e4SLinus Torvalds char name[64]; 2221da177e4SLinus Torvalds 2231da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2241da177e4SLinus Torvalds 2251da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2261da177e4SLinus Torvalds if(!dir) return; 2271da177e4SLinus Torvalds 2283f3942acSChristoph Hellwig ent = proc_create_single("media", S_IRUGO, dir, 2293f3942acSChristoph Hellwig fake_ide_media_proc_show); 2301da177e4SLinus Torvalds if(!ent) return; 231c0a9290eSWANG Cong snprintf(name, sizeof(name), "ide0/%s", dev_name); 2321da177e4SLinus Torvalds proc_symlink(dev_name, proc_ide_root, name); 2331da177e4SLinus Torvalds } 2341da177e4SLinus Torvalds 2351da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2361da177e4SLinus Torvalds { 2371da177e4SLinus Torvalds fake_ide = 1; 238dc764e50SJeff Dike return 1; 2391da177e4SLinus Torvalds } 2401da177e4SLinus Torvalds 2411da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2421da177e4SLinus Torvalds 2431da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2441da177e4SLinus Torvalds "fake_ide\n" 2451da177e4SLinus Torvalds " Create ide0 entries that map onto ubd devices.\n\n" 2461da177e4SLinus Torvalds ); 2471da177e4SLinus Torvalds 2481da177e4SLinus Torvalds static int parse_unit(char **ptr) 2491da177e4SLinus Torvalds { 2501da177e4SLinus Torvalds char *str = *ptr, *end; 2511da177e4SLinus Torvalds int n = -1; 2521da177e4SLinus Torvalds 2531da177e4SLinus Torvalds if(isdigit(*str)) { 2541da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2551da177e4SLinus Torvalds if(end == str) 256dc764e50SJeff Dike return -1; 2571da177e4SLinus Torvalds *ptr = end; 2581da177e4SLinus Torvalds } 25997d88ac8SPaolo 'Blaisorblade' Giarrusso else if (('a' <= *str) && (*str <= 'z')) { 2601da177e4SLinus Torvalds n = *str - 'a'; 2611da177e4SLinus Torvalds str++; 2621da177e4SLinus Torvalds *ptr = str; 2631da177e4SLinus Torvalds } 264dc764e50SJeff Dike return n; 2651da177e4SLinus Torvalds } 2661da177e4SLinus Torvalds 267d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* If *index_out == -1 at exit, the passed option was a general one; 268d8d7c28eSPaolo 'Blaisorblade' Giarrusso * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it 269d8d7c28eSPaolo 'Blaisorblade' Giarrusso * should not be freed on exit. 270d8d7c28eSPaolo 'Blaisorblade' Giarrusso */ 271f28169d2SJeff Dike static int ubd_setup_common(char *str, int *index_out, char **error_out) 2721da177e4SLinus Torvalds { 2737d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 2741da177e4SLinus Torvalds struct openflags flags = global_openflags; 2751da177e4SLinus Torvalds char *backing_file; 276b8831a1dSJeff Dike int n, err = 0, i; 2771da177e4SLinus Torvalds 2781da177e4SLinus Torvalds if(index_out) *index_out = -1; 2791da177e4SLinus Torvalds n = *str; 2801da177e4SLinus Torvalds if(n == '='){ 2811da177e4SLinus Torvalds char *end; 2821da177e4SLinus Torvalds int major; 2831da177e4SLinus Torvalds 2841da177e4SLinus Torvalds str++; 2851da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 2861da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 2879ca55299SDaniel Walter return err; 2881da177e4SLinus Torvalds } 2891da177e4SLinus Torvalds 290f28169d2SJeff Dike err = -EINVAL; 291b8831a1dSJeff Dike major = simple_strtoul(str, &end, 0); 292b8831a1dSJeff Dike if((*end != '\0') || (end == str)){ 293b8831a1dSJeff Dike *error_out = "Didn't parse major number"; 2949ca55299SDaniel Walter return err; 295b8831a1dSJeff Dike } 296b8831a1dSJeff Dike 297d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 298792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 299f28169d2SJeff Dike *error_out = "Can't assign a fake major twice"; 3001da177e4SLinus Torvalds goto out1; 3011da177e4SLinus Torvalds } 3021da177e4SLinus Torvalds 3031da177e4SLinus Torvalds fake_major = major; 3041da177e4SLinus Torvalds 3051da177e4SLinus Torvalds printk(KERN_INFO "Setting extra ubd major number to %d\n", 3061da177e4SLinus Torvalds major); 3071da177e4SLinus Torvalds err = 0; 3081da177e4SLinus Torvalds out1: 309d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 310f28169d2SJeff Dike return err; 3111da177e4SLinus Torvalds } 3121da177e4SLinus Torvalds 3131da177e4SLinus Torvalds n = parse_unit(&str); 3141da177e4SLinus Torvalds if(n < 0){ 315f28169d2SJeff Dike *error_out = "Couldn't parse device number"; 316f28169d2SJeff Dike return -EINVAL; 3171da177e4SLinus Torvalds } 3181da177e4SLinus Torvalds if(n >= MAX_DEV){ 319f28169d2SJeff Dike *error_out = "Device number out of range"; 320f28169d2SJeff Dike return 1; 3211da177e4SLinus Torvalds } 3221da177e4SLinus Torvalds 323f28169d2SJeff Dike err = -EBUSY; 324d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 3251da177e4SLinus Torvalds 3267d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 3277d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file != NULL){ 328f28169d2SJeff Dike *error_out = "Device is already configured"; 3291da177e4SLinus Torvalds goto out; 3301da177e4SLinus Torvalds } 3311da177e4SLinus Torvalds 3321da177e4SLinus Torvalds if (index_out) 3331da177e4SLinus Torvalds *index_out = n; 3341da177e4SLinus Torvalds 335f28169d2SJeff Dike err = -EINVAL; 33650109b5aSAnton Ivanov for (i = 0; i < sizeof("rscdt="); i++) { 3371da177e4SLinus Torvalds switch (*str) { 3381da177e4SLinus Torvalds case 'r': 3391da177e4SLinus Torvalds flags.w = 0; 3401da177e4SLinus Torvalds break; 3411da177e4SLinus Torvalds case 's': 3421da177e4SLinus Torvalds flags.s = 1; 3431da177e4SLinus Torvalds break; 3441da177e4SLinus Torvalds case 'd': 3457d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->no_cow = 1; 3461da177e4SLinus Torvalds break; 3476c29256cSJeff Dike case 'c': 3487d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->shared = 1; 3496c29256cSJeff Dike break; 35050109b5aSAnton Ivanov case 't': 35150109b5aSAnton Ivanov ubd_dev->no_trim = 1; 35250109b5aSAnton Ivanov break; 3531da177e4SLinus Torvalds case '=': 3541da177e4SLinus Torvalds str++; 3551da177e4SLinus Torvalds goto break_loop; 3561da177e4SLinus Torvalds default: 357f28169d2SJeff Dike *error_out = "Expected '=' or flag letter " 35850109b5aSAnton Ivanov "(r, s, c, t or d)"; 3591da177e4SLinus Torvalds goto out; 3601da177e4SLinus Torvalds } 3611da177e4SLinus Torvalds str++; 3621da177e4SLinus Torvalds } 3631da177e4SLinus Torvalds 3641da177e4SLinus Torvalds if (*str == '=') 365f28169d2SJeff Dike *error_out = "Too many flags specified"; 3661da177e4SLinus Torvalds else 367f28169d2SJeff Dike *error_out = "Missing '='"; 3681da177e4SLinus Torvalds goto out; 3691da177e4SLinus Torvalds 3701da177e4SLinus Torvalds break_loop: 3711da177e4SLinus Torvalds backing_file = strchr(str, ','); 3721da177e4SLinus Torvalds 373f28169d2SJeff Dike if (backing_file == NULL) 3741da177e4SLinus Torvalds backing_file = strchr(str, ':'); 3751da177e4SLinus Torvalds 376f28169d2SJeff Dike if(backing_file != NULL){ 377f28169d2SJeff Dike if(ubd_dev->no_cow){ 378f28169d2SJeff Dike *error_out = "Can't specify both 'd' and a cow file"; 379f28169d2SJeff Dike goto out; 380f28169d2SJeff Dike } 3811da177e4SLinus Torvalds else { 3821da177e4SLinus Torvalds *backing_file = '\0'; 3831da177e4SLinus Torvalds backing_file++; 3841da177e4SLinus Torvalds } 3851da177e4SLinus Torvalds } 386f28169d2SJeff Dike err = 0; 3877d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->file = str; 3887d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.file = backing_file; 3897d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->boot_openflags = flags; 3901da177e4SLinus Torvalds out: 391d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 392f28169d2SJeff Dike return err; 3931da177e4SLinus Torvalds } 3941da177e4SLinus Torvalds 3951da177e4SLinus Torvalds static int ubd_setup(char *str) 3961da177e4SLinus Torvalds { 397f28169d2SJeff Dike char *error; 398f28169d2SJeff Dike int err; 399f28169d2SJeff Dike 400f28169d2SJeff Dike err = ubd_setup_common(str, NULL, &error); 401f28169d2SJeff Dike if(err) 402f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize device with \"%s\" : " 403f28169d2SJeff Dike "%s\n", str, error); 404f28169d2SJeff Dike return 1; 4051da177e4SLinus Torvalds } 4061da177e4SLinus Torvalds 4071da177e4SLinus Torvalds __setup("ubd", ubd_setup); 4081da177e4SLinus Torvalds __uml_help(ubd_setup, 4091da177e4SLinus Torvalds "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" 4101da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 4111da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 4121da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 4131da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 4141da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 4151da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 416f28169d2SJeff Dike " When using only one filename, UML will detect whether to treat it like\n" 4171da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 4181da177e4SLinus Torvalds " flag:\n" 4191da177e4SLinus Torvalds " ubd0d=BackingFile\n" 4201da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 4211da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 4221da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 4231da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 4241da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 4251da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 4261da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 42720ede453SJeff Dike " an 's' will cause data to be written to disk on the host immediately.\n" 42820ede453SJeff Dike " 'c' will cause the device to be treated as being shared between multiple\n" 42920ede453SJeff Dike " UMLs and file locking will be turned off - this is appropriate for a\n" 43020ede453SJeff Dike " cluster filesystem and inappropriate at almost all other times.\n\n" 43150109b5aSAnton Ivanov " 't' will disable trim/discard support on the device (enabled by default).\n\n" 4321da177e4SLinus Torvalds ); 4331da177e4SLinus Torvalds 4348299ca5cSJeff Dike static int udb_setup(char *str) 4351da177e4SLinus Torvalds { 4361da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 4371da177e4SLinus Torvalds "udb TYPO\n", str); 438dc764e50SJeff Dike return 1; 4391da177e4SLinus Torvalds } 4401da177e4SLinus Torvalds 4411da177e4SLinus Torvalds __setup("udb", udb_setup); 4421da177e4SLinus Torvalds __uml_help(udb_setup, 4431da177e4SLinus Torvalds "udb\n" 4440894e27eSJeff Dike " This option is here solely to catch ubd -> udb typos, which can be\n" 4450894e27eSJeff Dike " to impossible to catch visually unless you specifically look for\n" 4460894e27eSJeff Dike " them. The only result of any option starting with 'udb' is an error\n" 4471da177e4SLinus Torvalds " in the boot output.\n\n" 4481da177e4SLinus Torvalds ); 4491da177e4SLinus Torvalds 45091acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 4515dc62b1bSWANG Cong static int thread_fd = -1; 45209ace81cSJeff Dike 453f88f0bdfSAnton Ivanov /* Function to read several request pointers at a time 454f88f0bdfSAnton Ivanov * handling fractional reads if (and as) needed 455f88f0bdfSAnton Ivanov */ 456f88f0bdfSAnton Ivanov 457f88f0bdfSAnton Ivanov static int bulk_req_safe_read( 458f88f0bdfSAnton Ivanov int fd, 459f88f0bdfSAnton Ivanov struct io_thread_req * (*request_buffer)[], 460f88f0bdfSAnton Ivanov struct io_thread_req **remainder, 461f88f0bdfSAnton Ivanov int *remainder_size, 462f88f0bdfSAnton Ivanov int max_recs 463f88f0bdfSAnton Ivanov ) 464f88f0bdfSAnton Ivanov { 465f88f0bdfSAnton Ivanov int n = 0; 466f88f0bdfSAnton Ivanov int res = 0; 467f88f0bdfSAnton Ivanov 468f88f0bdfSAnton Ivanov if (*remainder_size > 0) { 469f88f0bdfSAnton Ivanov memmove( 470f88f0bdfSAnton Ivanov (char *) request_buffer, 471f88f0bdfSAnton Ivanov (char *) remainder, *remainder_size 472f88f0bdfSAnton Ivanov ); 473f88f0bdfSAnton Ivanov n = *remainder_size; 474f88f0bdfSAnton Ivanov } 475f88f0bdfSAnton Ivanov 476f88f0bdfSAnton Ivanov res = os_read_file( 477f88f0bdfSAnton Ivanov fd, 478f88f0bdfSAnton Ivanov ((char *) request_buffer) + *remainder_size, 479f88f0bdfSAnton Ivanov sizeof(struct io_thread_req *)*max_recs 480f88f0bdfSAnton Ivanov - *remainder_size 481f88f0bdfSAnton Ivanov ); 482f88f0bdfSAnton Ivanov if (res > 0) { 483f88f0bdfSAnton Ivanov n += res; 484f88f0bdfSAnton Ivanov if ((n % sizeof(struct io_thread_req *)) > 0) { 485f88f0bdfSAnton Ivanov /* 486f88f0bdfSAnton Ivanov * Read somehow returned not a multiple of dword 487f88f0bdfSAnton Ivanov * theoretically possible, but never observed in the 488f88f0bdfSAnton Ivanov * wild, so read routine must be able to handle it 489f88f0bdfSAnton Ivanov */ 490f88f0bdfSAnton Ivanov *remainder_size = n % sizeof(struct io_thread_req *); 491f88f0bdfSAnton Ivanov WARN(*remainder_size > 0, "UBD IPC read returned a partial result"); 492f88f0bdfSAnton Ivanov memmove( 493f88f0bdfSAnton Ivanov remainder, 494f88f0bdfSAnton Ivanov ((char *) request_buffer) + 495f88f0bdfSAnton Ivanov (n/sizeof(struct io_thread_req *))*sizeof(struct io_thread_req *), 496f88f0bdfSAnton Ivanov *remainder_size 497f88f0bdfSAnton Ivanov ); 498f88f0bdfSAnton Ivanov n = n - *remainder_size; 499f88f0bdfSAnton Ivanov } 500f88f0bdfSAnton Ivanov } else { 501f88f0bdfSAnton Ivanov n = res; 502f88f0bdfSAnton Ivanov } 503f88f0bdfSAnton Ivanov return n; 504f88f0bdfSAnton Ivanov } 505f88f0bdfSAnton Ivanov 50662f96cb0SJeff Dike /* Called without dev->lock held, and only in interrupt context. */ 50791acb21fSJeff Dike static void ubd_handler(void) 50891acb21fSJeff Dike { 50991acb21fSJeff Dike int n; 510f88f0bdfSAnton Ivanov int count; 51109ace81cSJeff Dike 512a0044bdfSJeff Dike while(1){ 513f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 514f88f0bdfSAnton Ivanov thread_fd, 515f88f0bdfSAnton Ivanov irq_req_buffer, 516f88f0bdfSAnton Ivanov &irq_remainder, 517f88f0bdfSAnton Ivanov &irq_remainder_size, 518f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 519f88f0bdfSAnton Ivanov ); 520f88f0bdfSAnton Ivanov if (n < 0) { 521a0044bdfSJeff Dike if(n == -EAGAIN) 522a0044bdfSJeff Dike break; 523a0044bdfSJeff Dike printk(KERN_ERR "spurious interrupt in ubd_handler, " 524a0044bdfSJeff Dike "err = %d\n", -n); 52591acb21fSJeff Dike return; 52691acb21fSJeff Dike } 527f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 5284e6da0feSRichard Weinberger struct io_thread_req *io_req = (*irq_req_buffer)[count]; 529a0044bdfSJeff Dike 53050109b5aSAnton Ivanov if ((io_req->error == BLK_STS_NOTSUPP) && (req_op(io_req->req) == REQ_OP_DISCARD)) { 53150109b5aSAnton Ivanov blk_queue_max_discard_sectors(io_req->req->q, 0); 53250109b5aSAnton Ivanov blk_queue_max_write_zeroes_sectors(io_req->req->q, 0); 53350109b5aSAnton Ivanov blk_queue_flag_clear(QUEUE_FLAG_DISCARD, io_req->req->q); 53450109b5aSAnton Ivanov } 53550109b5aSAnton Ivanov blk_mq_end_request(io_req->req, io_req->error); 5364e6da0feSRichard Weinberger kfree(io_req); 537a0044bdfSJeff Dike } 53891acb21fSJeff Dike } 5394e6da0feSRichard Weinberger } 5404e6da0feSRichard Weinberger 5417bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 5421da177e4SLinus Torvalds { 54391acb21fSJeff Dike ubd_handler(); 544dc764e50SJeff Dike return IRQ_HANDLED; 5451da177e4SLinus Torvalds } 5461da177e4SLinus Torvalds 54791acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 54891acb21fSJeff Dike static int io_pid = -1; 54991acb21fSJeff Dike 5505dc62b1bSWANG Cong static void kill_io_thread(void) 55191acb21fSJeff Dike { 55291acb21fSJeff Dike if(io_pid != -1) 55391acb21fSJeff Dike os_kill_process(io_pid, 1); 55491acb21fSJeff Dike } 55591acb21fSJeff Dike 55691acb21fSJeff Dike __uml_exitcall(kill_io_thread); 55791acb21fSJeff Dike 558d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5591da177e4SLinus Torvalds { 5601da177e4SLinus Torvalds char *file; 56185356398SRichard Weinberger int fd; 56285356398SRichard Weinberger int err; 5631da177e4SLinus Torvalds 56485356398SRichard Weinberger __u32 version; 56585356398SRichard Weinberger __u32 align; 56685356398SRichard Weinberger char *backing_file; 567853bc0abSArnd Bergmann time64_t mtime; 56885356398SRichard Weinberger unsigned long long size; 56985356398SRichard Weinberger int sector_size; 57085356398SRichard Weinberger int bitmap_offset; 57185356398SRichard Weinberger 57285356398SRichard Weinberger if (ubd_dev->file && ubd_dev->cow.file) { 57385356398SRichard Weinberger file = ubd_dev->cow.file; 57485356398SRichard Weinberger 57585356398SRichard Weinberger goto out; 57685356398SRichard Weinberger } 57785356398SRichard Weinberger 578d4afcba9SMartin Pärtel fd = os_open_file(ubd_dev->file, of_read(OPENFLAGS()), 0); 57985356398SRichard Weinberger if (fd < 0) 58085356398SRichard Weinberger return fd; 58185356398SRichard Weinberger 58285356398SRichard Weinberger err = read_cow_header(file_reader, &fd, &version, &backing_file, \ 58385356398SRichard Weinberger &mtime, &size, §or_size, &align, &bitmap_offset); 58485356398SRichard Weinberger os_close_file(fd); 58585356398SRichard Weinberger 58685356398SRichard Weinberger if(err == -EINVAL) 58785356398SRichard Weinberger file = ubd_dev->file; 58885356398SRichard Weinberger else 58985356398SRichard Weinberger file = backing_file; 59085356398SRichard Weinberger 59185356398SRichard Weinberger out: 592dc764e50SJeff Dike return os_file_size(file, size_out); 5931da177e4SLinus Torvalds } 5941da177e4SLinus Torvalds 5955dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 5965dc62b1bSWANG Cong { 5975dc62b1bSWANG Cong int err; 5985dc62b1bSWANG Cong 5998c6157b6SAnton Ivanov err = os_pread_file(fd, buf, len, offset); 6005dc62b1bSWANG Cong if (err < 0) 6015dc62b1bSWANG Cong return err; 6025dc62b1bSWANG Cong 6035dc62b1bSWANG Cong return 0; 6045dc62b1bSWANG Cong } 6055dc62b1bSWANG Cong 606853bc0abSArnd Bergmann static int backing_file_mismatch(char *file, __u64 size, time64_t mtime) 6075dc62b1bSWANG Cong { 608853bc0abSArnd Bergmann time64_t modtime; 6095dc62b1bSWANG Cong unsigned long long actual; 6105dc62b1bSWANG Cong int err; 6115dc62b1bSWANG Cong 6125dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 6135dc62b1bSWANG Cong if (err < 0) { 6145dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 6155dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 6165dc62b1bSWANG Cong return err; 6175dc62b1bSWANG Cong } 6185dc62b1bSWANG Cong 6195dc62b1bSWANG Cong err = os_file_size(file, &actual); 6205dc62b1bSWANG Cong if (err < 0) { 6215dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 6225dc62b1bSWANG Cong "err = %d\n", file, -err); 6235dc62b1bSWANG Cong return err; 6245dc62b1bSWANG Cong } 6255dc62b1bSWANG Cong 6265dc62b1bSWANG Cong if (actual != size) { 6275dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 6285dc62b1bSWANG Cong * the typecast.*/ 6295dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 6305dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 6315dc62b1bSWANG Cong return -EINVAL; 6325dc62b1bSWANG Cong } 6335dc62b1bSWANG Cong if (modtime != mtime) { 634853bc0abSArnd Bergmann printk(KERN_ERR "mtime mismatch (%lld vs %lld) of COW header vs " 6355dc62b1bSWANG Cong "backing file\n", mtime, modtime); 6365dc62b1bSWANG Cong return -EINVAL; 6375dc62b1bSWANG Cong } 6385dc62b1bSWANG Cong return 0; 6395dc62b1bSWANG Cong } 6405dc62b1bSWANG Cong 6415dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 6425dc62b1bSWANG Cong { 6435dc62b1bSWANG Cong struct uml_stat buf1, buf2; 6445dc62b1bSWANG Cong int err; 6455dc62b1bSWANG Cong 6465dc62b1bSWANG Cong if (from_cmdline == NULL) 6475dc62b1bSWANG Cong return 0; 6485dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 6495dc62b1bSWANG Cong return 0; 6505dc62b1bSWANG Cong 6515dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 6525dc62b1bSWANG Cong if (err < 0) { 6535dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 6545dc62b1bSWANG Cong -err); 6555dc62b1bSWANG Cong return 0; 6565dc62b1bSWANG Cong } 6575dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 6585dc62b1bSWANG Cong if (err < 0) { 6595dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 6605dc62b1bSWANG Cong -err); 6615dc62b1bSWANG Cong return 1; 6625dc62b1bSWANG Cong } 6635dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 6645dc62b1bSWANG Cong return 0; 6655dc62b1bSWANG Cong 6665dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 6675dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 6685dc62b1bSWANG Cong from_cmdline, from_cow, cow); 6695dc62b1bSWANG Cong return 1; 6705dc62b1bSWANG Cong } 6715dc62b1bSWANG Cong 6725dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 6735dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 6745dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6755dc62b1bSWANG Cong int *create_cow_out) 6765dc62b1bSWANG Cong { 677853bc0abSArnd Bergmann time64_t mtime; 6785dc62b1bSWANG Cong unsigned long long size; 6795dc62b1bSWANG Cong __u32 version, align; 6805dc62b1bSWANG Cong char *backing_file; 6815dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6825dc62b1bSWANG Cong 6835dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6845dc62b1bSWANG Cong if (fd < 0) { 6855dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6865dc62b1bSWANG Cong *create_cow_out = 1; 6875dc62b1bSWANG Cong if (!openflags->w || 6885dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 6895dc62b1bSWANG Cong return fd; 6905dc62b1bSWANG Cong openflags->w = 0; 6915dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6925dc62b1bSWANG Cong if (fd < 0) 6935dc62b1bSWANG Cong return fd; 6945dc62b1bSWANG Cong } 6955dc62b1bSWANG Cong 6965dc62b1bSWANG Cong if (shared) 6975dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 6985dc62b1bSWANG Cong else { 6995dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 7005dc62b1bSWANG Cong if (err < 0) { 7015dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 7025dc62b1bSWANG Cong file, -err); 7035dc62b1bSWANG Cong goto out_close; 7045dc62b1bSWANG Cong } 7055dc62b1bSWANG Cong } 7065dc62b1bSWANG Cong 7075dc62b1bSWANG Cong /* Successful return case! */ 7085dc62b1bSWANG Cong if (backing_file_out == NULL) 7095dc62b1bSWANG Cong return fd; 7105dc62b1bSWANG Cong 7115dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 7125dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 7135dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 7145dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 7155dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 7165dc62b1bSWANG Cong goto out_close; 7175dc62b1bSWANG Cong } 7185dc62b1bSWANG Cong if (err) 7195dc62b1bSWANG Cong return fd; 7205dc62b1bSWANG Cong 7215dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 7225dc62b1bSWANG Cong file); 7235dc62b1bSWANG Cong 7245dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 7255dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 7265dc62b1bSWANG Cong mtime)) { 7275dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 7285dc62b1bSWANG Cong *backing_file_out); 7295dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 7305dc62b1bSWANG Cong sectorsize, align, &size); 7315dc62b1bSWANG Cong if (err) { 7325dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 7335dc62b1bSWANG Cong goto out_close; 7345dc62b1bSWANG Cong } 7355dc62b1bSWANG Cong } else { 7365dc62b1bSWANG Cong *backing_file_out = backing_file; 7375dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 7385dc62b1bSWANG Cong if (err) 7395dc62b1bSWANG Cong goto out_close; 7405dc62b1bSWANG Cong } 7415dc62b1bSWANG Cong 7425dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 7435dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 7445dc62b1bSWANG Cong 7455dc62b1bSWANG Cong return fd; 7465dc62b1bSWANG Cong out_close: 7475dc62b1bSWANG Cong os_close_file(fd); 7485dc62b1bSWANG Cong return err; 7495dc62b1bSWANG Cong } 7505dc62b1bSWANG Cong 7515dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 7525dc62b1bSWANG Cong struct openflags flags, 7535dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 7545dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 7555dc62b1bSWANG Cong { 7565dc62b1bSWANG Cong int err, fd; 7575dc62b1bSWANG Cong 7585dc62b1bSWANG Cong flags.c = 1; 7595dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 7605dc62b1bSWANG Cong if (fd < 0) { 7615dc62b1bSWANG Cong err = fd; 7625dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 7635dc62b1bSWANG Cong cow_file, -err); 7645dc62b1bSWANG Cong goto out; 7655dc62b1bSWANG Cong } 7665dc62b1bSWANG Cong 7675dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 7685dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 7695dc62b1bSWANG Cong data_offset_out); 7705dc62b1bSWANG Cong if (!err) 7715dc62b1bSWANG Cong return fd; 7725dc62b1bSWANG Cong os_close_file(fd); 7735dc62b1bSWANG Cong out: 7745dc62b1bSWANG Cong return err; 7755dc62b1bSWANG Cong } 7765dc62b1bSWANG Cong 7775f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7781da177e4SLinus Torvalds { 7797d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7807d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7811da177e4SLinus Torvalds return; 7821da177e4SLinus Torvalds 7837d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7847d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7857d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7861da177e4SLinus Torvalds } 7871da177e4SLinus Torvalds 7887d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 7891da177e4SLinus Torvalds { 7901da177e4SLinus Torvalds struct openflags flags; 7911da177e4SLinus Torvalds char **back_ptr; 7921da177e4SLinus Torvalds int err, create_cow, *create_ptr; 7930bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 7941da177e4SLinus Torvalds 7957d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 7961da177e4SLinus Torvalds create_cow = 0; 7977d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 7987d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 7990bf16bffSPaolo 'Blaisorblade' Giarrusso 8000bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 8017d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 8027d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 8036c29256cSJeff Dike create_ptr); 8041da177e4SLinus Torvalds 8050bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 8060bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 807a43c8316SAnton Ivanov ubd_dev->openflags, SECTOR_SIZE, PAGE_SIZE, 8087d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 8097d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 8107d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 8110bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 8121da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 8137d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 8141da177e4SLinus Torvalds } 8151da177e4SLinus Torvalds } 8161da177e4SLinus Torvalds 8170bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 8187d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 8190bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 8200bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 8211da177e4SLinus Torvalds } 8220bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 8231da177e4SLinus Torvalds 8247d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 825086fa5ffSMartin K. Petersen blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); 826f4768ffdSJeff Dike 8271da177e4SLinus Torvalds err = -ENOMEM; 828da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 8297d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 8301da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 8311da177e4SLinus Torvalds goto error; 8321da177e4SLinus Torvalds } 8331da177e4SLinus Torvalds flush_tlb_kernel_vm(); 8341da177e4SLinus Torvalds 8357d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 8367d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 8377d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 8381da177e4SLinus Torvalds if(err < 0) 8391da177e4SLinus Torvalds goto error; 8401da177e4SLinus Torvalds 8417d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 8421da177e4SLinus Torvalds flags.w = 0; 8437d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 8446c29256cSJeff Dike NULL, NULL, NULL, NULL); 8451da177e4SLinus Torvalds if(err < 0) goto error; 8467d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 8471da177e4SLinus Torvalds } 84850109b5aSAnton Ivanov if (ubd_dev->no_trim == 0) { 84950109b5aSAnton Ivanov ubd_dev->queue->limits.discard_granularity = SECTOR_SIZE; 85050109b5aSAnton Ivanov ubd_dev->queue->limits.discard_alignment = SECTOR_SIZE; 85150109b5aSAnton Ivanov blk_queue_max_discard_sectors(ubd_dev->queue, UBD_MAX_REQUEST); 85250109b5aSAnton Ivanov blk_queue_max_write_zeroes_sectors(ubd_dev->queue, UBD_MAX_REQUEST); 85350109b5aSAnton Ivanov blk_queue_flag_set(QUEUE_FLAG_DISCARD, ubd_dev->queue); 85450109b5aSAnton Ivanov } 855a43c8316SAnton Ivanov blk_queue_flag_set(QUEUE_FLAG_NONROT, ubd_dev->queue); 856dc764e50SJeff Dike return 0; 8571da177e4SLinus Torvalds error: 8587d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 859dc764e50SJeff Dike return err; 8601da177e4SLinus Torvalds } 8611da177e4SLinus Torvalds 8622e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 8632e3f5251SJeff Dike { 8648691b97bSGreg Kroah-Hartman struct ubd *ubd_dev = dev_get_drvdata(dev); 8652e3f5251SJeff Dike 8662e3f5251SJeff Dike blk_cleanup_queue(ubd_dev->queue); 8674e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 8682e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 8692e3f5251SJeff Dike } 8702e3f5251SJeff Dike 8715f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 8721da177e4SLinus Torvalds struct gendisk **disk_out) 8731da177e4SLinus Torvalds { 874d72a5783SDan Williams struct device *parent = NULL; 8751da177e4SLinus Torvalds struct gendisk *disk; 8761da177e4SLinus Torvalds 8771da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 8781da177e4SLinus Torvalds if(disk == NULL) 879dc764e50SJeff Dike return -ENOMEM; 8801da177e4SLinus Torvalds 8811da177e4SLinus Torvalds disk->major = major; 8821da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 8831da177e4SLinus Torvalds disk->fops = &ubd_blops; 8841da177e4SLinus Torvalds set_capacity(disk, size / 512); 885792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) 8861da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 887ce7b0f46SGreg Kroah-Hartman else 8881da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 8891da177e4SLinus Torvalds 8901da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 891792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) { 8927d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 8937d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 8942e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 8958691b97bSGreg Kroah-Hartman dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); 8967d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 897d72a5783SDan Williams parent = &ubd_devs[unit].pdev.dev; 8981da177e4SLinus Torvalds } 8991da177e4SLinus Torvalds 9007d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 90162f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 902fef912bfSHannes Reinecke device_add_disk(parent, disk, NULL); 9031da177e4SLinus Torvalds 9041da177e4SLinus Torvalds *disk_out = disk; 9051da177e4SLinus Torvalds return 0; 9061da177e4SLinus Torvalds } 9071da177e4SLinus Torvalds 908a43c8316SAnton Ivanov #define ROUND_BLOCK(n) ((n + (SECTOR_SIZE - 1)) & (-SECTOR_SIZE)) 9091da177e4SLinus Torvalds 9104e6da0feSRichard Weinberger static const struct blk_mq_ops ubd_mq_ops = { 9114e6da0feSRichard Weinberger .queue_rq = ubd_queue_rq, 9124e6da0feSRichard Weinberger }; 9134e6da0feSRichard Weinberger 914f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 9151da177e4SLinus Torvalds { 9167d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 917f28169d2SJeff Dike int err = 0; 9181da177e4SLinus Torvalds 9197d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 920ec7cf783SJeff Dike goto out; 9211da177e4SLinus Torvalds 9227d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 923f28169d2SJeff Dike if(err < 0){ 924f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 92580c13749SJeff Dike goto out; 926f28169d2SJeff Dike } 9271da177e4SLinus Torvalds 9287d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 9291da177e4SLinus Torvalds 9304e6da0feSRichard Weinberger ubd_dev->tag_set.ops = &ubd_mq_ops; 9314e6da0feSRichard Weinberger ubd_dev->tag_set.queue_depth = 64; 9324e6da0feSRichard Weinberger ubd_dev->tag_set.numa_node = NUMA_NO_NODE; 9334e6da0feSRichard Weinberger ubd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; 9344e6da0feSRichard Weinberger ubd_dev->tag_set.driver_data = ubd_dev; 9354e6da0feSRichard Weinberger ubd_dev->tag_set.nr_hw_queues = 1; 936a0044bdfSJeff Dike 9374e6da0feSRichard Weinberger err = blk_mq_alloc_tag_set(&ubd_dev->tag_set); 9384e6da0feSRichard Weinberger if (err) 93980c13749SJeff Dike goto out; 9404e6da0feSRichard Weinberger 9414e6da0feSRichard Weinberger ubd_dev->queue = blk_mq_init_queue(&ubd_dev->tag_set); 9424e6da0feSRichard Weinberger if (IS_ERR(ubd_dev->queue)) { 9434e6da0feSRichard Weinberger err = PTR_ERR(ubd_dev->queue); 944aea05eb5SAnton Ivanov goto out_cleanup_tags; 94562f96cb0SJeff Dike } 9464e6da0feSRichard Weinberger 94762f96cb0SJeff Dike ubd_dev->queue->queuedata = ubd_dev; 948f935a8ceSJens Axboe blk_queue_write_cache(ubd_dev->queue, true, false); 94962f96cb0SJeff Dike 9508a78362cSMartin K. Petersen blk_queue_max_segments(ubd_dev->queue, MAX_SG); 951*fc6b6a87SGabriel Krisman Bertazi blk_queue_segment_boundary(ubd_dev->queue, PAGE_SIZE - 1); 952792dd4fcSChristoph Hellwig err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); 95362f96cb0SJeff Dike if(err){ 95462f96cb0SJeff Dike *error_out = "Failed to register device"; 9554e6da0feSRichard Weinberger goto out_cleanup_tags; 95662f96cb0SJeff Dike } 9571da177e4SLinus Torvalds 958792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) 9595f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 9601da177e4SLinus Torvalds &fake_gendisk[n]); 9611da177e4SLinus Torvalds 96283380cc1SJeff Dike /* 96383380cc1SJeff Dike * Perhaps this should also be under the "if (fake_major)" above 96483380cc1SJeff Dike * using the fake_disk->disk_name 96583380cc1SJeff Dike */ 9661da177e4SLinus Torvalds if (fake_ide) 9671da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 9681da177e4SLinus Torvalds 969ec7cf783SJeff Dike err = 0; 970ec7cf783SJeff Dike out: 971ec7cf783SJeff Dike return err; 97262f96cb0SJeff Dike 9734e6da0feSRichard Weinberger out_cleanup_tags: 9744e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 975aea05eb5SAnton Ivanov if (!(IS_ERR(ubd_dev->queue))) 97662f96cb0SJeff Dike blk_cleanup_queue(ubd_dev->queue); 97762f96cb0SJeff Dike goto out; 9781da177e4SLinus Torvalds } 9791da177e4SLinus Torvalds 980f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 9811da177e4SLinus Torvalds { 982e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 9831da177e4SLinus Torvalds 984f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 985f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 986f28169d2SJeff Dike * were set. 987f28169d2SJeff Dike */ 988970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 9891da177e4SLinus Torvalds if (str == NULL) { 990f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 991f28169d2SJeff Dike return -ENOMEM; 9921da177e4SLinus Torvalds } 993f28169d2SJeff Dike 994f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 995f28169d2SJeff Dike if (ret) 996e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 997f28169d2SJeff Dike 998e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 999e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 1000d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 1001e7f6552fSPaolo 'Blaisorblade' Giarrusso } 10021da177e4SLinus Torvalds 1003d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 1004f28169d2SJeff Dike ret = ubd_add(n, error_out); 1005e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 10067d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 1007d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 10081da177e4SLinus Torvalds 1009e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 1010e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 1011e7f6552fSPaolo 'Blaisorblade' Giarrusso 1012e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 1013e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 1014e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 10151da177e4SLinus Torvalds } 10161da177e4SLinus Torvalds 10171da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 10181da177e4SLinus Torvalds { 10197d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 10201da177e4SLinus Torvalds int n, len = 0; 10211da177e4SLinus Torvalds 10221da177e4SLinus Torvalds n = parse_unit(&name); 10231da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 10241da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 1025dc764e50SJeff Dike return -1; 10261da177e4SLinus Torvalds } 10271da177e4SLinus Torvalds 10287d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 1029d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10301da177e4SLinus Torvalds 10317d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 10321da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 10331da177e4SLinus Torvalds goto out; 10341da177e4SLinus Torvalds } 10351da177e4SLinus Torvalds 10367d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 10371da177e4SLinus Torvalds 10387d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 10391da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 10407d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 10411da177e4SLinus Torvalds } 10421da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 10431da177e4SLinus Torvalds 10441da177e4SLinus Torvalds out: 1045d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 1046dc764e50SJeff Dike return len; 10471da177e4SLinus Torvalds } 10481da177e4SLinus Torvalds 104929d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 105029d56cfeSJeff Dike { 105129d56cfeSJeff Dike int n; 105229d56cfeSJeff Dike 105329d56cfeSJeff Dike n = parse_unit(str); 105429d56cfeSJeff Dike *start_out = 0; 105529d56cfeSJeff Dike *end_out = MAX_DEV - 1; 105629d56cfeSJeff Dike return n; 105729d56cfeSJeff Dike } 105829d56cfeSJeff Dike 1059f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 10601da177e4SLinus Torvalds { 10612e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 10627d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 106329d56cfeSJeff Dike int err = -ENODEV; 10641da177e4SLinus Torvalds 1065d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10661da177e4SLinus Torvalds 10677d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 106829d56cfeSJeff Dike 10697d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 107029d56cfeSJeff Dike goto out; 107129d56cfeSJeff Dike 107229d56cfeSJeff Dike /* you cannot remove a open disk */ 107329d56cfeSJeff Dike err = -EBUSY; 10747d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 107529d56cfeSJeff Dike goto out; 107629d56cfeSJeff Dike 10771da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 1078b47d2debSJeff Dike if(disk != NULL){ 1079b47d2debSJeff Dike del_gendisk(disk); 1080b47d2debSJeff Dike put_disk(disk); 1081b47d2debSJeff Dike } 10821da177e4SLinus Torvalds 10831da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 10841da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 10851da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 10861da177e4SLinus Torvalds fake_gendisk[n] = NULL; 10871da177e4SLinus Torvalds } 10881da177e4SLinus Torvalds 10891da177e4SLinus Torvalds err = 0; 10902e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 10911da177e4SLinus Torvalds out: 1092d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 109329d56cfeSJeff Dike return err; 10941da177e4SLinus Torvalds } 10951da177e4SLinus Torvalds 1096f28169d2SJeff Dike /* All these are called by mconsole in process context and without 1097b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 1098f28169d2SJeff Dike */ 10991da177e4SLinus Torvalds static struct mc_device ubd_mc = { 110084f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 11011da177e4SLinus Torvalds .name = "ubd", 11021da177e4SLinus Torvalds .config = ubd_config, 11031da177e4SLinus Torvalds .get_config = ubd_get_config, 110429d56cfeSJeff Dike .id = ubd_id, 11051da177e4SLinus Torvalds .remove = ubd_remove, 11061da177e4SLinus Torvalds }; 11071da177e4SLinus Torvalds 1108d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 11091da177e4SLinus Torvalds { 11101da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 11111da177e4SLinus Torvalds return 0; 11121da177e4SLinus Torvalds } 11131da177e4SLinus Torvalds 11141da177e4SLinus Torvalds __initcall(ubd_mc_init); 11151da177e4SLinus Torvalds 1116d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1117d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1118d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1119d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1120b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1121d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1122d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1123b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1124b8831a1dSJeff Dike 1125dc764e50SJeff Dike return 0; 1126d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1127d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1128d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1129d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1130b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 11313ae5eaecSRussell King static struct platform_driver ubd_driver = { 11323ae5eaecSRussell King .driver = { 11331da177e4SLinus Torvalds .name = DRIVER_NAME, 11343ae5eaecSRussell King }, 11351da177e4SLinus Torvalds }; 11361da177e4SLinus Torvalds 1137d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 11381da177e4SLinus Torvalds { 1139f28169d2SJeff Dike char *error; 1140f28169d2SJeff Dike int i, err; 11411da177e4SLinus Torvalds 1142792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 11431da177e4SLinus Torvalds return -1; 11441da177e4SLinus Torvalds 1145792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 11461da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 11471da177e4SLinus Torvalds 11481da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 11491da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 11501da177e4SLinus Torvalds return -1; 11511da177e4SLinus Torvalds } 1152f88f0bdfSAnton Ivanov 11536da2ec56SKees Cook irq_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11546da2ec56SKees Cook sizeof(struct io_thread_req *), 1155f88f0bdfSAnton Ivanov GFP_KERNEL 1156f88f0bdfSAnton Ivanov ); 1157f88f0bdfSAnton Ivanov irq_remainder = 0; 1158f88f0bdfSAnton Ivanov 1159f88f0bdfSAnton Ivanov if (irq_req_buffer == NULL) { 1160f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1161f88f0bdfSAnton Ivanov return -1; 1162f88f0bdfSAnton Ivanov } 11636da2ec56SKees Cook io_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11646da2ec56SKees Cook sizeof(struct io_thread_req *), 1165f88f0bdfSAnton Ivanov GFP_KERNEL 1166f88f0bdfSAnton Ivanov ); 1167f88f0bdfSAnton Ivanov 1168f88f0bdfSAnton Ivanov io_remainder = 0; 1169f88f0bdfSAnton Ivanov 1170f88f0bdfSAnton Ivanov if (io_req_buffer == NULL) { 1171f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1172f88f0bdfSAnton Ivanov return -1; 1173f88f0bdfSAnton Ivanov } 11743ae5eaecSRussell King platform_driver_register(&ubd_driver); 1175b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1176f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1177f28169d2SJeff Dike err = ubd_add(i, &error); 1178f28169d2SJeff Dike if(err) 1179f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1180f28169d2SJeff Dike "%s\n", i, error); 1181f28169d2SJeff Dike } 1182b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 11831da177e4SLinus Torvalds return 0; 11841da177e4SLinus Torvalds } 11851da177e4SLinus Torvalds 11861da177e4SLinus Torvalds late_initcall(ubd_init); 11871da177e4SLinus Torvalds 1188d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 118991acb21fSJeff Dike unsigned long stack; 119091acb21fSJeff Dike int err; 119191acb21fSJeff Dike 119291acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 119391acb21fSJeff Dike if(global_openflags.s){ 119491acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 119591acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 119691acb21fSJeff Dike * enough. So use anyway the io thread. */ 119791acb21fSJeff Dike } 119891acb21fSJeff Dike stack = alloc_stack(0, 0); 119991acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 120091acb21fSJeff Dike &thread_fd); 120191acb21fSJeff Dike if(io_pid < 0){ 120291acb21fSJeff Dike printk(KERN_ERR 120391acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 120491acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 120591acb21fSJeff Dike io_pid = -1; 1206dc764e50SJeff Dike return 0; 120791acb21fSJeff Dike } 120891acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 1209c0b79a90SYong Zhang 0, "ubd", ubd_devs); 121091acb21fSJeff Dike if(err != 0) 121191acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1212f4c57a78SJeff Dike return 0; 121391acb21fSJeff Dike } 121491acb21fSJeff Dike 121591acb21fSJeff Dike device_initcall(ubd_driver_init); 121691acb21fSJeff Dike 1217a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 12181da177e4SLinus Torvalds { 1219a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 12207d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12211da177e4SLinus Torvalds int err = 0; 12221da177e4SLinus Torvalds 12239a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12247d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 12257d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 12261da177e4SLinus Torvalds if(err){ 12271da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 12287d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 12291da177e4SLinus Torvalds goto out; 12301da177e4SLinus Torvalds } 12311da177e4SLinus Torvalds } 12327d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 12337d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 12342c49be99SPaolo 'Blaisorblade' Giarrusso 12352c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 12362c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1237a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 12385f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 12391da177e4SLinus Torvalds err = -EROFS; 12402c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 12411da177e4SLinus Torvalds out: 12429a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 1243dc764e50SJeff Dike return err; 12441da177e4SLinus Torvalds } 12451da177e4SLinus Torvalds 1246db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode) 12471da177e4SLinus Torvalds { 12487d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12491da177e4SLinus Torvalds 12509a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12517d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 12525f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 12539a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 12541da177e4SLinus Torvalds } 12551da177e4SLinus Torvalds 125691acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 125791acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 125891acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 125991acb21fSJeff Dike __u64 bitmap_len) 12601da177e4SLinus Torvalds { 1261a43c8316SAnton Ivanov __u64 sector = io_offset >> SECTOR_SHIFT; 126291acb21fSJeff Dike int i, update_bitmap = 0; 12631da177e4SLinus Torvalds 1264a43c8316SAnton Ivanov for (i = 0; i < length >> SECTOR_SHIFT; i++) { 126591acb21fSJeff Dike if(cow_mask != NULL) 126691acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 126791acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 126809ace81cSJeff Dike continue; 12691da177e4SLinus Torvalds 127091acb21fSJeff Dike update_bitmap = 1; 127191acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 12721da177e4SLinus Torvalds } 127391acb21fSJeff Dike 127491acb21fSJeff Dike if(!update_bitmap) 127591acb21fSJeff Dike return; 127691acb21fSJeff Dike 127791acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 127891acb21fSJeff Dike 127991acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 128091acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 128191acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 128291acb21fSJeff Dike * for the original diagnosis. 128391acb21fSJeff Dike */ 12846d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 12856d074242SJiri Olsa sizeof(unsigned long)) - 1)) 128691acb21fSJeff Dike (*cow_offset)--; 128791acb21fSJeff Dike 128891acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 128991acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 129091acb21fSJeff Dike 129191acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 129291acb21fSJeff Dike *cow_offset += bitmap_offset; 129391acb21fSJeff Dike } 129491acb21fSJeff Dike 1295*fc6b6a87SGabriel Krisman Bertazi static void cowify_req(struct io_thread_req *req, struct io_desc *segment, 1296*fc6b6a87SGabriel Krisman Bertazi unsigned long offset, unsigned long *bitmap, 129791acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 129891acb21fSJeff Dike { 1299*fc6b6a87SGabriel Krisman Bertazi __u64 sector = offset >> SECTOR_SHIFT; 130091acb21fSJeff Dike int i; 130191acb21fSJeff Dike 1302*fc6b6a87SGabriel Krisman Bertazi if (segment->length > (sizeof(segment->sector_mask) * 8) << SECTOR_SHIFT) 130391acb21fSJeff Dike panic("Operation too long"); 130491acb21fSJeff Dike 1305a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_READ) { 1306*fc6b6a87SGabriel Krisman Bertazi for (i = 0; i < segment->length >> SECTOR_SHIFT; i++) { 130791acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 130891acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 1309*fc6b6a87SGabriel Krisman Bertazi &segment->sector_mask); 131091acb21fSJeff Dike } 1311*fc6b6a87SGabriel Krisman Bertazi } else { 1312*fc6b6a87SGabriel Krisman Bertazi cowify_bitmap(offset, segment->length, &segment->sector_mask, 1313*fc6b6a87SGabriel Krisman Bertazi &segment->cow_offset, bitmap, bitmap_offset, 1314*fc6b6a87SGabriel Krisman Bertazi segment->bitmap_words, bitmap_len); 131591acb21fSJeff Dike } 13161da177e4SLinus Torvalds } 13171da177e4SLinus Torvalds 1318*fc6b6a87SGabriel Krisman Bertazi static void ubd_map_req(struct ubd *dev, struct io_thread_req *io_req, 1319*fc6b6a87SGabriel Krisman Bertazi struct request *req) 13201da177e4SLinus Torvalds { 1321*fc6b6a87SGabriel Krisman Bertazi struct bio_vec bvec; 1322*fc6b6a87SGabriel Krisman Bertazi struct req_iterator iter; 1323*fc6b6a87SGabriel Krisman Bertazi int i = 0; 1324*fc6b6a87SGabriel Krisman Bertazi unsigned long byte_offset = io_req->offset; 1325*fc6b6a87SGabriel Krisman Bertazi int op = req_op(req); 1326ecb0a83eSChristoph Hellwig 1327*fc6b6a87SGabriel Krisman Bertazi if (op == REQ_OP_WRITE_ZEROES || op == REQ_OP_DISCARD) { 1328*fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[0].buffer = NULL; 1329*fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[0].length = blk_rq_bytes(req); 1330*fc6b6a87SGabriel Krisman Bertazi } else { 1331*fc6b6a87SGabriel Krisman Bertazi rq_for_each_segment(bvec, req, iter) { 1332*fc6b6a87SGabriel Krisman Bertazi BUG_ON(i >= io_req->desc_cnt); 1333*fc6b6a87SGabriel Krisman Bertazi 1334*fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].buffer = 1335*fc6b6a87SGabriel Krisman Bertazi page_address(bvec.bv_page) + bvec.bv_offset; 1336*fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].length = bvec.bv_len; 1337*fc6b6a87SGabriel Krisman Bertazi i++; 1338*fc6b6a87SGabriel Krisman Bertazi } 1339*fc6b6a87SGabriel Krisman Bertazi } 1340*fc6b6a87SGabriel Krisman Bertazi 1341*fc6b6a87SGabriel Krisman Bertazi if (dev->cow.file) { 1342*fc6b6a87SGabriel Krisman Bertazi for (i = 0; i < io_req->desc_cnt; i++) { 1343*fc6b6a87SGabriel Krisman Bertazi cowify_req(io_req, &io_req->io_desc[i], byte_offset, 1344*fc6b6a87SGabriel Krisman Bertazi dev->cow.bitmap, dev->cow.bitmap_offset, 1345*fc6b6a87SGabriel Krisman Bertazi dev->cow.bitmap_len); 1346*fc6b6a87SGabriel Krisman Bertazi byte_offset += io_req->io_desc[i].length; 1347*fc6b6a87SGabriel Krisman Bertazi } 1348*fc6b6a87SGabriel Krisman Bertazi 1349*fc6b6a87SGabriel Krisman Bertazi } 1350*fc6b6a87SGabriel Krisman Bertazi } 1351*fc6b6a87SGabriel Krisman Bertazi 1352*fc6b6a87SGabriel Krisman Bertazi static struct io_thread_req *ubd_alloc_req(struct ubd *dev, struct request *req, 1353*fc6b6a87SGabriel Krisman Bertazi int desc_cnt) 1354*fc6b6a87SGabriel Krisman Bertazi { 1355*fc6b6a87SGabriel Krisman Bertazi struct io_thread_req *io_req; 1356*fc6b6a87SGabriel Krisman Bertazi int i; 1357*fc6b6a87SGabriel Krisman Bertazi 1358*fc6b6a87SGabriel Krisman Bertazi io_req = kmalloc(sizeof(*io_req) + 1359*fc6b6a87SGabriel Krisman Bertazi (desc_cnt * sizeof(struct io_desc)), 1360*fc6b6a87SGabriel Krisman Bertazi GFP_ATOMIC); 1361ecb0a83eSChristoph Hellwig if (!io_req) 1362*fc6b6a87SGabriel Krisman Bertazi return NULL; 136391acb21fSJeff Dike 136462f96cb0SJeff Dike io_req->req = req; 1365ecb0a83eSChristoph Hellwig if (dev->cow.file) 1366ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->cow.fd; 1367ecb0a83eSChristoph Hellwig else 1368ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->fd; 13690033dfd9SAnton Ivanov io_req->error = 0; 137053766defSAnton Ivanov io_req->sectorsize = SECTOR_SIZE; 1371ecb0a83eSChristoph Hellwig io_req->fds[1] = dev->fd; 1372*fc6b6a87SGabriel Krisman Bertazi io_req->offset = (u64) blk_rq_pos(req) << SECTOR_SHIFT; 13731da177e4SLinus Torvalds io_req->offsets[0] = 0; 1374ecb0a83eSChristoph Hellwig io_req->offsets[1] = dev->cow.data_offset; 13751da177e4SLinus Torvalds 1376*fc6b6a87SGabriel Krisman Bertazi for (i = 0 ; i < desc_cnt; i++) { 1377*fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].sector_mask = 0; 1378*fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].cow_offset = -1; 1379*fc6b6a87SGabriel Krisman Bertazi } 1380*fc6b6a87SGabriel Krisman Bertazi 1381*fc6b6a87SGabriel Krisman Bertazi return io_req; 1382*fc6b6a87SGabriel Krisman Bertazi } 1383*fc6b6a87SGabriel Krisman Bertazi 1384*fc6b6a87SGabriel Krisman Bertazi static int ubd_submit_request(struct ubd *dev, struct request *req) 1385*fc6b6a87SGabriel Krisman Bertazi { 1386*fc6b6a87SGabriel Krisman Bertazi int segs = 0; 1387*fc6b6a87SGabriel Krisman Bertazi struct io_thread_req *io_req; 1388*fc6b6a87SGabriel Krisman Bertazi int ret; 1389*fc6b6a87SGabriel Krisman Bertazi int op = req_op(req); 1390*fc6b6a87SGabriel Krisman Bertazi 1391*fc6b6a87SGabriel Krisman Bertazi if (op == REQ_OP_FLUSH) 1392*fc6b6a87SGabriel Krisman Bertazi segs = 0; 1393*fc6b6a87SGabriel Krisman Bertazi else if (op == REQ_OP_WRITE_ZEROES || op == REQ_OP_DISCARD) 1394*fc6b6a87SGabriel Krisman Bertazi segs = 1; 1395*fc6b6a87SGabriel Krisman Bertazi else 1396*fc6b6a87SGabriel Krisman Bertazi segs = blk_rq_nr_phys_segments(req); 1397*fc6b6a87SGabriel Krisman Bertazi 1398*fc6b6a87SGabriel Krisman Bertazi io_req = ubd_alloc_req(dev, req, segs); 1399*fc6b6a87SGabriel Krisman Bertazi if (!io_req) 1400*fc6b6a87SGabriel Krisman Bertazi return -ENOMEM; 1401*fc6b6a87SGabriel Krisman Bertazi 1402*fc6b6a87SGabriel Krisman Bertazi io_req->desc_cnt = segs; 1403*fc6b6a87SGabriel Krisman Bertazi if (segs) 1404*fc6b6a87SGabriel Krisman Bertazi ubd_map_req(dev, io_req, req); 14051da177e4SLinus Torvalds 1406ecb0a83eSChristoph Hellwig ret = os_write_file(thread_fd, &io_req, sizeof(io_req)); 1407ecb0a83eSChristoph Hellwig if (ret != sizeof(io_req)) { 1408ecb0a83eSChristoph Hellwig if (ret != -EAGAIN) 1409ecb0a83eSChristoph Hellwig pr_err("write to io thread failed: %d\n", -ret); 1410bc1d72e7SRichard Weinberger kfree(io_req); 1411bc1d72e7SRichard Weinberger } 1412ecb0a83eSChristoph Hellwig return ret; 1413bc1d72e7SRichard Weinberger } 1414bc1d72e7SRichard Weinberger 14154e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 14164e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd) 14171da177e4SLinus Torvalds { 14186961cd4dSJens Axboe struct ubd *ubd_dev = hctx->queue->queuedata; 14194e6da0feSRichard Weinberger struct request *req = bd->rq; 142053766defSAnton Ivanov int ret = 0, res = BLK_STS_OK; 14211da177e4SLinus Torvalds 14224e6da0feSRichard Weinberger blk_mq_start_request(req); 1423a0044bdfSJeff Dike 14246961cd4dSJens Axboe spin_lock_irq(&ubd_dev->lock); 14256961cd4dSJens Axboe 142653766defSAnton Ivanov switch (req_op(req)) { 142753766defSAnton Ivanov case REQ_OP_FLUSH: 142853766defSAnton Ivanov case REQ_OP_READ: 142953766defSAnton Ivanov case REQ_OP_WRITE: 143050109b5aSAnton Ivanov case REQ_OP_DISCARD: 143150109b5aSAnton Ivanov case REQ_OP_WRITE_ZEROES: 1432*fc6b6a87SGabriel Krisman Bertazi ret = ubd_submit_request(ubd_dev, req); 143350109b5aSAnton Ivanov break; 143453766defSAnton Ivanov default: 143553766defSAnton Ivanov WARN_ON_ONCE(1); 143653766defSAnton Ivanov res = BLK_STS_NOTSUPP; 143753766defSAnton Ivanov } 1438ecb0a83eSChristoph Hellwig 14396961cd4dSJens Axboe spin_unlock_irq(&ubd_dev->lock); 14406961cd4dSJens Axboe 1441d848074bSAnton Ivanov if (ret < 0) { 1442d848074bSAnton Ivanov if (ret == -ENOMEM) 1443d848074bSAnton Ivanov res = BLK_STS_RESOURCE; 1444d848074bSAnton Ivanov else 1445d848074bSAnton Ivanov res = BLK_STS_DEV_RESOURCE; 1446d848074bSAnton Ivanov } 14476961cd4dSJens Axboe 144853766defSAnton Ivanov return res; 144991acb21fSJeff Dike } 14504e6da0feSRichard Weinberger 1451a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1452a885c8c4SChristoph Hellwig { 14537d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1454a885c8c4SChristoph Hellwig 1455a885c8c4SChristoph Hellwig geo->heads = 128; 1456a885c8c4SChristoph Hellwig geo->sectors = 32; 14577d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1458a885c8c4SChristoph Hellwig return 0; 1459a885c8c4SChristoph Hellwig } 1460a885c8c4SChristoph Hellwig 1461a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 14621da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 14631da177e4SLinus Torvalds { 1464a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 146573855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 14661da177e4SLinus Torvalds 14671da177e4SLinus Torvalds switch (cmd) { 14681da177e4SLinus Torvalds struct cdrom_volctrl volume; 14691da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 147073855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 147173855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 147273855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 147373855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 14741da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 14751da177e4SLinus Torvalds sizeof(ubd_id))) 1476dc764e50SJeff Dike return -EFAULT; 1477dc764e50SJeff Dike return 0; 14781da177e4SLinus Torvalds 14791da177e4SLinus Torvalds case CDROMVOLREAD: 14801da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1481dc764e50SJeff Dike return -EFAULT; 14821da177e4SLinus Torvalds volume.channel0 = 255; 14831da177e4SLinus Torvalds volume.channel1 = 255; 14841da177e4SLinus Torvalds volume.channel2 = 255; 14851da177e4SLinus Torvalds volume.channel3 = 255; 14861da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1487dc764e50SJeff Dike return -EFAULT; 1488dc764e50SJeff Dike return 0; 14891da177e4SLinus Torvalds } 1490dc764e50SJeff Dike return -EINVAL; 14911da177e4SLinus Torvalds } 14921da177e4SLinus Torvalds 1493a43c8316SAnton Ivanov static int map_error(int error_code) 1494a43c8316SAnton Ivanov { 1495a43c8316SAnton Ivanov switch (error_code) { 1496a43c8316SAnton Ivanov case 0: 1497a43c8316SAnton Ivanov return BLK_STS_OK; 1498a43c8316SAnton Ivanov case ENOSYS: 1499a43c8316SAnton Ivanov case EOPNOTSUPP: 1500a43c8316SAnton Ivanov return BLK_STS_NOTSUPP; 1501a43c8316SAnton Ivanov case ENOSPC: 1502a43c8316SAnton Ivanov return BLK_STS_NOSPC; 1503a43c8316SAnton Ivanov } 1504a43c8316SAnton Ivanov return BLK_STS_IOERR; 1505a43c8316SAnton Ivanov } 1506a43c8316SAnton Ivanov 1507a41421edSAnton Ivanov /* 1508a41421edSAnton Ivanov * Everything from here onwards *IS NOT PART OF THE KERNEL* 1509a41421edSAnton Ivanov * 1510a41421edSAnton Ivanov * The following functions are part of UML hypervisor code. 1511a41421edSAnton Ivanov * All functions from here onwards are executed as a helper 1512a41421edSAnton Ivanov * thread and are not allowed to execute any kernel functions. 1513a41421edSAnton Ivanov * 1514a41421edSAnton Ivanov * Any communication must occur strictly via shared memory and IPC. 1515a41421edSAnton Ivanov * 1516a41421edSAnton Ivanov * Do not add printks, locks, kernel memory operations, etc - it 1517a41421edSAnton Ivanov * will result in unpredictable behaviour and/or crashes. 1518a41421edSAnton Ivanov */ 1519a41421edSAnton Ivanov 1520*fc6b6a87SGabriel Krisman Bertazi static int update_bitmap(struct io_thread_req *req, struct io_desc *segment) 15211da177e4SLinus Torvalds { 152291acb21fSJeff Dike int n; 152391acb21fSJeff Dike 1524*fc6b6a87SGabriel Krisman Bertazi if (segment->cow_offset == -1) 1525a43c8316SAnton Ivanov return map_error(0); 152691acb21fSJeff Dike 1527*fc6b6a87SGabriel Krisman Bertazi n = os_pwrite_file(req->fds[1], &segment->bitmap_words, 1528*fc6b6a87SGabriel Krisman Bertazi sizeof(segment->bitmap_words), segment->cow_offset); 1529*fc6b6a87SGabriel Krisman Bertazi if (n != sizeof(segment->bitmap_words)) 1530a43c8316SAnton Ivanov return map_error(-n); 153191acb21fSJeff Dike 1532a43c8316SAnton Ivanov return map_error(0); 153391acb21fSJeff Dike } 153491acb21fSJeff Dike 1535*fc6b6a87SGabriel Krisman Bertazi static void do_io(struct io_thread_req *req, struct io_desc *desc) 153691acb21fSJeff Dike { 153750109b5aSAnton Ivanov char *buf = NULL; 153891acb21fSJeff Dike unsigned long len; 153991acb21fSJeff Dike int n, nsectors, start, end, bit; 15401da177e4SLinus Torvalds __u64 off; 15411da177e4SLinus Torvalds 154250109b5aSAnton Ivanov /* FLUSH is really a special case, we cannot "case" it with others */ 154350109b5aSAnton Ivanov 1544a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_FLUSH) { 1545805f11a0SRichard Weinberger /* fds[0] is always either the rw image or our cow file */ 1546a41421edSAnton Ivanov req->error = map_error(-os_sync_file(req->fds[0])); 1547805f11a0SRichard Weinberger return; 1548805f11a0SRichard Weinberger } 1549805f11a0SRichard Weinberger 1550*fc6b6a87SGabriel Krisman Bertazi nsectors = desc->length / req->sectorsize; 15511da177e4SLinus Torvalds start = 0; 15521da177e4SLinus Torvalds do { 1553*fc6b6a87SGabriel Krisman Bertazi bit = ubd_test_bit(start, (unsigned char *) &desc->sector_mask); 15541da177e4SLinus Torvalds end = start; 15551da177e4SLinus Torvalds while((end < nsectors) && 1556*fc6b6a87SGabriel Krisman Bertazi (ubd_test_bit(end, (unsigned char *) &desc->sector_mask) == bit)) 15571da177e4SLinus Torvalds end++; 15581da177e4SLinus Torvalds 155991acb21fSJeff Dike off = req->offset + req->offsets[bit] + 15601da177e4SLinus Torvalds start * req->sectorsize; 15611da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 1562*fc6b6a87SGabriel Krisman Bertazi if (desc->buffer != NULL) 1563*fc6b6a87SGabriel Krisman Bertazi buf = &desc->buffer[start * req->sectorsize]; 15641da177e4SLinus Torvalds 156550109b5aSAnton Ivanov switch (req_op(req->req)) { 156650109b5aSAnton Ivanov case REQ_OP_READ: 156791acb21fSJeff Dike n = 0; 156891acb21fSJeff Dike do { 156991acb21fSJeff Dike buf = &buf[n]; 157091acb21fSJeff Dike len -= n; 15718c6157b6SAnton Ivanov n = os_pread_file(req->fds[bit], buf, len, off); 157291acb21fSJeff Dike if (n < 0) { 1573a43c8316SAnton Ivanov req->error = map_error(-n); 15741da177e4SLinus Torvalds return; 15751da177e4SLinus Torvalds } 157691acb21fSJeff Dike } while((n < len) && (n != 0)); 157791acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 157850109b5aSAnton Ivanov break; 157950109b5aSAnton Ivanov case REQ_OP_WRITE: 15808c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[bit], buf, len, off); 158191acb21fSJeff Dike if(n != len){ 1582a43c8316SAnton Ivanov req->error = map_error(-n); 158391acb21fSJeff Dike return; 158491acb21fSJeff Dike } 158550109b5aSAnton Ivanov break; 158650109b5aSAnton Ivanov case REQ_OP_DISCARD: 158750109b5aSAnton Ivanov case REQ_OP_WRITE_ZEROES: 158850109b5aSAnton Ivanov n = os_falloc_punch(req->fds[bit], off, len); 158950109b5aSAnton Ivanov if (n) { 159050109b5aSAnton Ivanov req->error = map_error(-n); 159150109b5aSAnton Ivanov return; 159250109b5aSAnton Ivanov } 159350109b5aSAnton Ivanov break; 159450109b5aSAnton Ivanov default: 159550109b5aSAnton Ivanov WARN_ON_ONCE(1); 159650109b5aSAnton Ivanov req->error = BLK_STS_NOTSUPP; 159750109b5aSAnton Ivanov return; 159891acb21fSJeff Dike } 15991da177e4SLinus Torvalds 16001da177e4SLinus Torvalds start = end; 16011da177e4SLinus Torvalds } while(start < nsectors); 160291acb21fSJeff Dike 1603*fc6b6a87SGabriel Krisman Bertazi req->offset += len; 1604*fc6b6a87SGabriel Krisman Bertazi req->error = update_bitmap(req, desc); 16051da177e4SLinus Torvalds } 160691acb21fSJeff Dike 160791acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 160891acb21fSJeff Dike * from ubd_init, which is an initcall. 160991acb21fSJeff Dike */ 161091acb21fSJeff Dike int kernel_fd = -1; 161191acb21fSJeff Dike 1612d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1613d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 161491acb21fSJeff Dike 161591acb21fSJeff Dike int io_thread(void *arg) 161691acb21fSJeff Dike { 1617f88f0bdfSAnton Ivanov int n, count, written, res; 161891acb21fSJeff Dike 161991d44ff8SRichard Weinberger os_fix_helper_signals(); 162091d44ff8SRichard Weinberger 162191acb21fSJeff Dike while(1){ 1622f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 1623f88f0bdfSAnton Ivanov kernel_fd, 1624f88f0bdfSAnton Ivanov io_req_buffer, 1625f88f0bdfSAnton Ivanov &io_remainder, 1626f88f0bdfSAnton Ivanov &io_remainder_size, 1627f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 1628f88f0bdfSAnton Ivanov ); 1629e355b2f5SGabriel Krisman Bertazi if (n <= 0) { 1630e355b2f5SGabriel Krisman Bertazi if (n == -EAGAIN) 1631f88f0bdfSAnton Ivanov ubd_read_poll(-1); 1632e355b2f5SGabriel Krisman Bertazi 1633f88f0bdfSAnton Ivanov continue; 1634f88f0bdfSAnton Ivanov } 1635f88f0bdfSAnton Ivanov 1636f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 1637*fc6b6a87SGabriel Krisman Bertazi struct io_thread_req *req = (*io_req_buffer)[count]; 1638*fc6b6a87SGabriel Krisman Bertazi int i; 1639*fc6b6a87SGabriel Krisman Bertazi 1640f88f0bdfSAnton Ivanov io_count++; 1641*fc6b6a87SGabriel Krisman Bertazi for (i = 0; !req->error && i < req->desc_cnt; i++) 1642*fc6b6a87SGabriel Krisman Bertazi do_io(req, &(req->io_desc[i])); 1643*fc6b6a87SGabriel Krisman Bertazi 1644f88f0bdfSAnton Ivanov } 1645f88f0bdfSAnton Ivanov 1646f88f0bdfSAnton Ivanov written = 0; 1647f88f0bdfSAnton Ivanov 1648f88f0bdfSAnton Ivanov do { 16496e682d53SGabriel Krisman Bertazi res = os_write_file(kernel_fd, 16506e682d53SGabriel Krisman Bertazi ((char *) io_req_buffer) + written, 16516e682d53SGabriel Krisman Bertazi n - written); 1652ff6a1798SAnton Ivanov if (res >= 0) { 1653f88f0bdfSAnton Ivanov written += res; 165491acb21fSJeff Dike } 1655f88f0bdfSAnton Ivanov if (written < n) { 1656f88f0bdfSAnton Ivanov ubd_write_poll(-1); 1657f88f0bdfSAnton Ivanov } 1658f88f0bdfSAnton Ivanov } while (written < n); 165991acb21fSJeff Dike } 166091acb21fSJeff Dike 16611b57e9c2SJeff Dike return 0; 16621b57e9c2SJeff Dike } 1663