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 */ 1281da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1291da177e4SLinus Torvalds 1301da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1311da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1321da177e4SLinus Torvalds .cl = 1 }) 1331da177e4SLinus Torvalds #else 1341da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1351da177e4SLinus Torvalds .cl = 1 }) 1361da177e4SLinus Torvalds #endif 1371da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1381da177e4SLinus Torvalds 1391da177e4SLinus Torvalds struct cow { 1402a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file name */ 1411da177e4SLinus Torvalds char *file; 1422a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file fd */ 1431da177e4SLinus Torvalds int fd; 1441da177e4SLinus Torvalds unsigned long *bitmap; 1451da177e4SLinus Torvalds unsigned long bitmap_len; 1461da177e4SLinus Torvalds int bitmap_offset; 1471da177e4SLinus Torvalds int data_offset; 1481da177e4SLinus Torvalds }; 1491da177e4SLinus Torvalds 150a0044bdfSJeff Dike #define MAX_SG 64 151a0044bdfSJeff Dike 1521da177e4SLinus Torvalds struct ubd { 1532a9d32f6SPaolo 'Blaisorblade' Giarrusso /* name (and fd, below) of the file opened for writing, either the 1542a9d32f6SPaolo 'Blaisorblade' Giarrusso * backing or the cow file. */ 1551da177e4SLinus Torvalds char *file; 156ef3ba87cSChristopher Obbard char *serial; 1571da177e4SLinus Torvalds int count; 1581da177e4SLinus Torvalds int fd; 1591da177e4SLinus Torvalds __u64 size; 1601da177e4SLinus Torvalds struct openflags boot_openflags; 1611da177e4SLinus Torvalds struct openflags openflags; 16284e945e3SPaolo 'Blaisorblade' Giarrusso unsigned shared:1; 16384e945e3SPaolo 'Blaisorblade' Giarrusso unsigned no_cow:1; 16450109b5aSAnton Ivanov unsigned no_trim:1; 1651da177e4SLinus Torvalds struct cow cow; 1661da177e4SLinus Torvalds struct platform_device pdev; 16762f96cb0SJeff Dike struct request_queue *queue; 1684e6da0feSRichard Weinberger struct blk_mq_tag_set tag_set; 16962f96cb0SJeff Dike spinlock_t lock; 1704e6da0feSRichard Weinberger }; 1714e6da0feSRichard Weinberger 1721da177e4SLinus Torvalds #define DEFAULT_COW { \ 1731da177e4SLinus Torvalds .file = NULL, \ 1741da177e4SLinus Torvalds .fd = -1, \ 1751da177e4SLinus Torvalds .bitmap = NULL, \ 1761da177e4SLinus Torvalds .bitmap_offset = 0, \ 1771da177e4SLinus Torvalds .data_offset = 0, \ 1781da177e4SLinus Torvalds } 1791da177e4SLinus Torvalds 1801da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1811da177e4SLinus Torvalds .file = NULL, \ 182ef3ba87cSChristopher Obbard .serial = 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 1984e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 1994e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd); 2004e6da0feSRichard Weinberger 2011da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2021da177e4SLinus Torvalds { 2037eb90f7eSChristoph Hellwig pr_warn("The fake_ide option has been removed\n"); 204dc764e50SJeff Dike return 1; 2051da177e4SLinus Torvalds } 2061da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2071da177e4SLinus Torvalds 2081da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2091da177e4SLinus Torvalds "fake_ide\n" 2107eb90f7eSChristoph Hellwig " Obsolete stub.\n\n" 2111da177e4SLinus Torvalds ); 2121da177e4SLinus Torvalds 2131da177e4SLinus Torvalds static int parse_unit(char **ptr) 2141da177e4SLinus Torvalds { 2151da177e4SLinus Torvalds char *str = *ptr, *end; 2161da177e4SLinus Torvalds int n = -1; 2171da177e4SLinus Torvalds 2181da177e4SLinus Torvalds if(isdigit(*str)) { 2191da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2201da177e4SLinus Torvalds if(end == str) 221dc764e50SJeff Dike return -1; 2221da177e4SLinus Torvalds *ptr = end; 2231da177e4SLinus Torvalds } 22497d88ac8SPaolo 'Blaisorblade' Giarrusso else if (('a' <= *str) && (*str <= 'z')) { 2251da177e4SLinus Torvalds n = *str - 'a'; 2261da177e4SLinus Torvalds str++; 2271da177e4SLinus Torvalds *ptr = str; 2281da177e4SLinus Torvalds } 229dc764e50SJeff Dike return n; 2301da177e4SLinus Torvalds } 2311da177e4SLinus Torvalds 232d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* If *index_out == -1 at exit, the passed option was a general one; 233d8d7c28eSPaolo 'Blaisorblade' Giarrusso * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it 234d8d7c28eSPaolo 'Blaisorblade' Giarrusso * should not be freed on exit. 235d8d7c28eSPaolo 'Blaisorblade' Giarrusso */ 236f28169d2SJeff Dike static int ubd_setup_common(char *str, int *index_out, char **error_out) 2371da177e4SLinus Torvalds { 2387d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 2391da177e4SLinus Torvalds struct openflags flags = global_openflags; 240ef3ba87cSChristopher Obbard char *file, *backing_file, *serial; 241b8831a1dSJeff Dike int n, err = 0, i; 2421da177e4SLinus Torvalds 2431da177e4SLinus Torvalds if(index_out) *index_out = -1; 2441da177e4SLinus Torvalds n = *str; 2451da177e4SLinus Torvalds if(n == '='){ 2461da177e4SLinus Torvalds char *end; 2471da177e4SLinus Torvalds int major; 2481da177e4SLinus Torvalds 2491da177e4SLinus Torvalds str++; 2501da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 2511da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 2529ca55299SDaniel Walter return err; 2531da177e4SLinus Torvalds } 2541da177e4SLinus Torvalds 255f28169d2SJeff Dike err = -EINVAL; 256b8831a1dSJeff Dike major = simple_strtoul(str, &end, 0); 257b8831a1dSJeff Dike if((*end != '\0') || (end == str)){ 258b8831a1dSJeff Dike *error_out = "Didn't parse major number"; 2599ca55299SDaniel Walter return err; 260b8831a1dSJeff Dike } 261b8831a1dSJeff Dike 2627eb90f7eSChristoph Hellwig pr_warn("fake major not supported any more\n"); 2637eb90f7eSChristoph Hellwig return 0; 2641da177e4SLinus Torvalds } 2651da177e4SLinus Torvalds 2661da177e4SLinus Torvalds n = parse_unit(&str); 2671da177e4SLinus Torvalds if(n < 0){ 268f28169d2SJeff Dike *error_out = "Couldn't parse device number"; 269f28169d2SJeff Dike return -EINVAL; 2701da177e4SLinus Torvalds } 2711da177e4SLinus Torvalds if(n >= MAX_DEV){ 272f28169d2SJeff Dike *error_out = "Device number out of range"; 273f28169d2SJeff Dike return 1; 2741da177e4SLinus Torvalds } 2751da177e4SLinus Torvalds 276f28169d2SJeff Dike err = -EBUSY; 277d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 2781da177e4SLinus Torvalds 2797d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 2807d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file != NULL){ 281f28169d2SJeff Dike *error_out = "Device is already configured"; 2821da177e4SLinus Torvalds goto out; 2831da177e4SLinus Torvalds } 2841da177e4SLinus Torvalds 2851da177e4SLinus Torvalds if (index_out) 2861da177e4SLinus Torvalds *index_out = n; 2871da177e4SLinus Torvalds 288f28169d2SJeff Dike err = -EINVAL; 28950109b5aSAnton Ivanov for (i = 0; i < sizeof("rscdt="); i++) { 2901da177e4SLinus Torvalds switch (*str) { 2911da177e4SLinus Torvalds case 'r': 2921da177e4SLinus Torvalds flags.w = 0; 2931da177e4SLinus Torvalds break; 2941da177e4SLinus Torvalds case 's': 2951da177e4SLinus Torvalds flags.s = 1; 2961da177e4SLinus Torvalds break; 2971da177e4SLinus Torvalds case 'd': 2987d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->no_cow = 1; 2991da177e4SLinus Torvalds break; 3006c29256cSJeff Dike case 'c': 3017d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->shared = 1; 3026c29256cSJeff Dike break; 30350109b5aSAnton Ivanov case 't': 30450109b5aSAnton Ivanov ubd_dev->no_trim = 1; 30550109b5aSAnton Ivanov break; 3061da177e4SLinus Torvalds case '=': 3071da177e4SLinus Torvalds str++; 3081da177e4SLinus Torvalds goto break_loop; 3091da177e4SLinus Torvalds default: 310f28169d2SJeff Dike *error_out = "Expected '=' or flag letter " 31150109b5aSAnton Ivanov "(r, s, c, t or d)"; 3121da177e4SLinus Torvalds goto out; 3131da177e4SLinus Torvalds } 3141da177e4SLinus Torvalds str++; 3151da177e4SLinus Torvalds } 3161da177e4SLinus Torvalds 3171da177e4SLinus Torvalds if (*str == '=') 318f28169d2SJeff Dike *error_out = "Too many flags specified"; 3191da177e4SLinus Torvalds else 320f28169d2SJeff Dike *error_out = "Missing '='"; 3211da177e4SLinus Torvalds goto out; 3221da177e4SLinus Torvalds 3231da177e4SLinus Torvalds break_loop: 324ef3ba87cSChristopher Obbard file = strsep(&str, ",:"); 325ef3ba87cSChristopher Obbard if (*file == '\0') 326ef3ba87cSChristopher Obbard file = NULL; 3271da177e4SLinus Torvalds 328ef3ba87cSChristopher Obbard backing_file = strsep(&str, ",:"); 32994c41b3aSHajime Tazaki if (backing_file && *backing_file == '\0') 330ef3ba87cSChristopher Obbard backing_file = NULL; 3311da177e4SLinus Torvalds 332ef3ba87cSChristopher Obbard serial = strsep(&str, ",:"); 33394c41b3aSHajime Tazaki if (serial && *serial == '\0') 334ef3ba87cSChristopher Obbard serial = NULL; 335ef3ba87cSChristopher Obbard 336ef3ba87cSChristopher Obbard if (backing_file && ubd_dev->no_cow) { 337f28169d2SJeff Dike *error_out = "Can't specify both 'd' and a cow file"; 338f28169d2SJeff Dike goto out; 339f28169d2SJeff Dike } 340ef3ba87cSChristopher Obbard 341f28169d2SJeff Dike err = 0; 342ef3ba87cSChristopher Obbard ubd_dev->file = file; 3437d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.file = backing_file; 344ef3ba87cSChristopher Obbard ubd_dev->serial = serial; 3457d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->boot_openflags = flags; 3461da177e4SLinus Torvalds out: 347d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 348f28169d2SJeff Dike return err; 3491da177e4SLinus Torvalds } 3501da177e4SLinus Torvalds 3511da177e4SLinus Torvalds static int ubd_setup(char *str) 3521da177e4SLinus Torvalds { 353f28169d2SJeff Dike char *error; 354f28169d2SJeff Dike int err; 355f28169d2SJeff Dike 356f28169d2SJeff Dike err = ubd_setup_common(str, NULL, &error); 357f28169d2SJeff Dike if(err) 358f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize device with \"%s\" : " 359f28169d2SJeff Dike "%s\n", str, error); 360f28169d2SJeff Dike return 1; 3611da177e4SLinus Torvalds } 3621da177e4SLinus Torvalds 3631da177e4SLinus Torvalds __setup("ubd", ubd_setup); 3641da177e4SLinus Torvalds __uml_help(ubd_setup, 365ef3ba87cSChristopher Obbard "ubd<n><flags>=<filename>[(:|,)<filename2>][(:|,)<serial>]\n" 3661da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 3671da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 3681da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 3691da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 3701da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 3711da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 372f28169d2SJeff Dike " When using only one filename, UML will detect whether to treat it like\n" 3731da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 3741da177e4SLinus Torvalds " flag:\n" 3751da177e4SLinus Torvalds " ubd0d=BackingFile\n" 3761da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 3771da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 3781da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 3791da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 3801da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 3811da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 3821da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 38320ede453SJeff Dike " an 's' will cause data to be written to disk on the host immediately.\n" 38420ede453SJeff Dike " 'c' will cause the device to be treated as being shared between multiple\n" 38520ede453SJeff Dike " UMLs and file locking will be turned off - this is appropriate for a\n" 38620ede453SJeff Dike " cluster filesystem and inappropriate at almost all other times.\n\n" 38750109b5aSAnton Ivanov " 't' will disable trim/discard support on the device (enabled by default).\n\n" 388ef3ba87cSChristopher Obbard " An optional device serial number can be exposed using the serial parameter\n" 389ef3ba87cSChristopher Obbard " on the cmdline which is exposed as a sysfs entry. This is particularly\n" 390ef3ba87cSChristopher Obbard " useful when a unique number should be given to the device. Note when\n" 391ef3ba87cSChristopher Obbard " specifying a label, the filename2 must be also presented. It can be\n" 392ef3ba87cSChristopher Obbard " an empty string, in which case the backing file is not used:\n" 393ef3ba87cSChristopher Obbard " ubd0=File,,Serial\n" 3941da177e4SLinus Torvalds ); 3951da177e4SLinus Torvalds 3968299ca5cSJeff Dike static int udb_setup(char *str) 3971da177e4SLinus Torvalds { 3981da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 3991da177e4SLinus Torvalds "udb TYPO\n", str); 400dc764e50SJeff Dike return 1; 4011da177e4SLinus Torvalds } 4021da177e4SLinus Torvalds 4031da177e4SLinus Torvalds __setup("udb", udb_setup); 4041da177e4SLinus Torvalds __uml_help(udb_setup, 4051da177e4SLinus Torvalds "udb\n" 4060894e27eSJeff Dike " This option is here solely to catch ubd -> udb typos, which can be\n" 4070894e27eSJeff Dike " to impossible to catch visually unless you specifically look for\n" 4080894e27eSJeff Dike " them. The only result of any option starting with 'udb' is an error\n" 4091da177e4SLinus Torvalds " in the boot output.\n\n" 4101da177e4SLinus Torvalds ); 4111da177e4SLinus Torvalds 41291acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 4135dc62b1bSWANG Cong static int thread_fd = -1; 41409ace81cSJeff Dike 415f88f0bdfSAnton Ivanov /* Function to read several request pointers at a time 416f88f0bdfSAnton Ivanov * handling fractional reads if (and as) needed 417f88f0bdfSAnton Ivanov */ 418f88f0bdfSAnton Ivanov 419f88f0bdfSAnton Ivanov static int bulk_req_safe_read( 420f88f0bdfSAnton Ivanov int fd, 421f88f0bdfSAnton Ivanov struct io_thread_req * (*request_buffer)[], 422f88f0bdfSAnton Ivanov struct io_thread_req **remainder, 423f88f0bdfSAnton Ivanov int *remainder_size, 424f88f0bdfSAnton Ivanov int max_recs 425f88f0bdfSAnton Ivanov ) 426f88f0bdfSAnton Ivanov { 427f88f0bdfSAnton Ivanov int n = 0; 428f88f0bdfSAnton Ivanov int res = 0; 429f88f0bdfSAnton Ivanov 430f88f0bdfSAnton Ivanov if (*remainder_size > 0) { 431f88f0bdfSAnton Ivanov memmove( 432f88f0bdfSAnton Ivanov (char *) request_buffer, 433f88f0bdfSAnton Ivanov (char *) remainder, *remainder_size 434f88f0bdfSAnton Ivanov ); 435f88f0bdfSAnton Ivanov n = *remainder_size; 436f88f0bdfSAnton Ivanov } 437f88f0bdfSAnton Ivanov 438f88f0bdfSAnton Ivanov res = os_read_file( 439f88f0bdfSAnton Ivanov fd, 440f88f0bdfSAnton Ivanov ((char *) request_buffer) + *remainder_size, 441f88f0bdfSAnton Ivanov sizeof(struct io_thread_req *)*max_recs 442f88f0bdfSAnton Ivanov - *remainder_size 443f88f0bdfSAnton Ivanov ); 444f88f0bdfSAnton Ivanov if (res > 0) { 445f88f0bdfSAnton Ivanov n += res; 446f88f0bdfSAnton Ivanov if ((n % sizeof(struct io_thread_req *)) > 0) { 447f88f0bdfSAnton Ivanov /* 448f88f0bdfSAnton Ivanov * Read somehow returned not a multiple of dword 449f88f0bdfSAnton Ivanov * theoretically possible, but never observed in the 450f88f0bdfSAnton Ivanov * wild, so read routine must be able to handle it 451f88f0bdfSAnton Ivanov */ 452f88f0bdfSAnton Ivanov *remainder_size = n % sizeof(struct io_thread_req *); 453f88f0bdfSAnton Ivanov WARN(*remainder_size > 0, "UBD IPC read returned a partial result"); 454f88f0bdfSAnton Ivanov memmove( 455f88f0bdfSAnton Ivanov remainder, 456f88f0bdfSAnton Ivanov ((char *) request_buffer) + 457f88f0bdfSAnton Ivanov (n/sizeof(struct io_thread_req *))*sizeof(struct io_thread_req *), 458f88f0bdfSAnton Ivanov *remainder_size 459f88f0bdfSAnton Ivanov ); 460f88f0bdfSAnton Ivanov n = n - *remainder_size; 461f88f0bdfSAnton Ivanov } 462f88f0bdfSAnton Ivanov } else { 463f88f0bdfSAnton Ivanov n = res; 464f88f0bdfSAnton Ivanov } 465f88f0bdfSAnton Ivanov return n; 466f88f0bdfSAnton Ivanov } 467f88f0bdfSAnton Ivanov 46862f96cb0SJeff Dike /* Called without dev->lock held, and only in interrupt context. */ 46991acb21fSJeff Dike static void ubd_handler(void) 47091acb21fSJeff Dike { 47191acb21fSJeff Dike int n; 472f88f0bdfSAnton Ivanov int count; 47309ace81cSJeff Dike 474a0044bdfSJeff Dike while(1){ 475f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 476f88f0bdfSAnton Ivanov thread_fd, 477f88f0bdfSAnton Ivanov irq_req_buffer, 478f88f0bdfSAnton Ivanov &irq_remainder, 479f88f0bdfSAnton Ivanov &irq_remainder_size, 480f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 481f88f0bdfSAnton Ivanov ); 482f88f0bdfSAnton Ivanov if (n < 0) { 483a0044bdfSJeff Dike if(n == -EAGAIN) 484a0044bdfSJeff Dike break; 485a0044bdfSJeff Dike printk(KERN_ERR "spurious interrupt in ubd_handler, " 486a0044bdfSJeff Dike "err = %d\n", -n); 48791acb21fSJeff Dike return; 48891acb21fSJeff Dike } 489f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 4904e6da0feSRichard Weinberger struct io_thread_req *io_req = (*irq_req_buffer)[count]; 491a0044bdfSJeff Dike 49250109b5aSAnton Ivanov if ((io_req->error == BLK_STS_NOTSUPP) && (req_op(io_req->req) == REQ_OP_DISCARD)) { 49350109b5aSAnton Ivanov blk_queue_max_discard_sectors(io_req->req->q, 0); 49450109b5aSAnton Ivanov blk_queue_max_write_zeroes_sectors(io_req->req->q, 0); 49550109b5aSAnton Ivanov blk_queue_flag_clear(QUEUE_FLAG_DISCARD, io_req->req->q); 49650109b5aSAnton Ivanov } 49750109b5aSAnton Ivanov blk_mq_end_request(io_req->req, io_req->error); 4984e6da0feSRichard Weinberger kfree(io_req); 499a0044bdfSJeff Dike } 50091acb21fSJeff Dike } 5014e6da0feSRichard Weinberger } 5024e6da0feSRichard Weinberger 5037bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 5041da177e4SLinus Torvalds { 50591acb21fSJeff Dike ubd_handler(); 506dc764e50SJeff Dike return IRQ_HANDLED; 5071da177e4SLinus Torvalds } 5081da177e4SLinus Torvalds 50991acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 51091acb21fSJeff Dike static int io_pid = -1; 51191acb21fSJeff Dike 5125dc62b1bSWANG Cong static void kill_io_thread(void) 51391acb21fSJeff Dike { 51491acb21fSJeff Dike if(io_pid != -1) 51591acb21fSJeff Dike os_kill_process(io_pid, 1); 51691acb21fSJeff Dike } 51791acb21fSJeff Dike 51891acb21fSJeff Dike __uml_exitcall(kill_io_thread); 51991acb21fSJeff Dike 520d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5211da177e4SLinus Torvalds { 5221da177e4SLinus Torvalds char *file; 52385356398SRichard Weinberger int fd; 52485356398SRichard Weinberger int err; 5251da177e4SLinus Torvalds 52685356398SRichard Weinberger __u32 version; 52785356398SRichard Weinberger __u32 align; 52885356398SRichard Weinberger char *backing_file; 529853bc0abSArnd Bergmann time64_t mtime; 53085356398SRichard Weinberger unsigned long long size; 53185356398SRichard Weinberger int sector_size; 53285356398SRichard Weinberger int bitmap_offset; 53385356398SRichard Weinberger 53485356398SRichard Weinberger if (ubd_dev->file && ubd_dev->cow.file) { 53585356398SRichard Weinberger file = ubd_dev->cow.file; 53685356398SRichard Weinberger 53785356398SRichard Weinberger goto out; 53885356398SRichard Weinberger } 53985356398SRichard Weinberger 540d4afcba9SMartin Pärtel fd = os_open_file(ubd_dev->file, of_read(OPENFLAGS()), 0); 54185356398SRichard Weinberger if (fd < 0) 54285356398SRichard Weinberger return fd; 54385356398SRichard Weinberger 54485356398SRichard Weinberger err = read_cow_header(file_reader, &fd, &version, &backing_file, \ 54585356398SRichard Weinberger &mtime, &size, §or_size, &align, &bitmap_offset); 54685356398SRichard Weinberger os_close_file(fd); 54785356398SRichard Weinberger 54885356398SRichard Weinberger if(err == -EINVAL) 54985356398SRichard Weinberger file = ubd_dev->file; 55085356398SRichard Weinberger else 55185356398SRichard Weinberger file = backing_file; 55285356398SRichard Weinberger 55385356398SRichard Weinberger out: 554dc764e50SJeff Dike return os_file_size(file, size_out); 5551da177e4SLinus Torvalds } 5561da177e4SLinus Torvalds 5575dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 5585dc62b1bSWANG Cong { 5595dc62b1bSWANG Cong int err; 5605dc62b1bSWANG Cong 5618c6157b6SAnton Ivanov err = os_pread_file(fd, buf, len, offset); 5625dc62b1bSWANG Cong if (err < 0) 5635dc62b1bSWANG Cong return err; 5645dc62b1bSWANG Cong 5655dc62b1bSWANG Cong return 0; 5665dc62b1bSWANG Cong } 5675dc62b1bSWANG Cong 568853bc0abSArnd Bergmann static int backing_file_mismatch(char *file, __u64 size, time64_t mtime) 5695dc62b1bSWANG Cong { 570853bc0abSArnd Bergmann time64_t modtime; 5715dc62b1bSWANG Cong unsigned long long actual; 5725dc62b1bSWANG Cong int err; 5735dc62b1bSWANG Cong 5745dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 5755dc62b1bSWANG Cong if (err < 0) { 5765dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 5775dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 5785dc62b1bSWANG Cong return err; 5795dc62b1bSWANG Cong } 5805dc62b1bSWANG Cong 5815dc62b1bSWANG Cong err = os_file_size(file, &actual); 5825dc62b1bSWANG Cong if (err < 0) { 5835dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 5845dc62b1bSWANG Cong "err = %d\n", file, -err); 5855dc62b1bSWANG Cong return err; 5865dc62b1bSWANG Cong } 5875dc62b1bSWANG Cong 5885dc62b1bSWANG Cong if (actual != size) { 5895dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 5905dc62b1bSWANG Cong * the typecast.*/ 5915dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 5925dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 5935dc62b1bSWANG Cong return -EINVAL; 5945dc62b1bSWANG Cong } 5955dc62b1bSWANG Cong if (modtime != mtime) { 596853bc0abSArnd Bergmann printk(KERN_ERR "mtime mismatch (%lld vs %lld) of COW header vs " 5975dc62b1bSWANG Cong "backing file\n", mtime, modtime); 5985dc62b1bSWANG Cong return -EINVAL; 5995dc62b1bSWANG Cong } 6005dc62b1bSWANG Cong return 0; 6015dc62b1bSWANG Cong } 6025dc62b1bSWANG Cong 6035dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 6045dc62b1bSWANG Cong { 6055dc62b1bSWANG Cong struct uml_stat buf1, buf2; 6065dc62b1bSWANG Cong int err; 6075dc62b1bSWANG Cong 6085dc62b1bSWANG Cong if (from_cmdline == NULL) 6095dc62b1bSWANG Cong return 0; 6105dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 6115dc62b1bSWANG Cong return 0; 6125dc62b1bSWANG Cong 6135dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 6145dc62b1bSWANG Cong if (err < 0) { 6155dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 6165dc62b1bSWANG Cong -err); 6175dc62b1bSWANG Cong return 0; 6185dc62b1bSWANG Cong } 6195dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 6205dc62b1bSWANG Cong if (err < 0) { 6215dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 6225dc62b1bSWANG Cong -err); 6235dc62b1bSWANG Cong return 1; 6245dc62b1bSWANG Cong } 6255dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 6265dc62b1bSWANG Cong return 0; 6275dc62b1bSWANG Cong 6285dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 6295dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 6305dc62b1bSWANG Cong from_cmdline, from_cow, cow); 6315dc62b1bSWANG Cong return 1; 6325dc62b1bSWANG Cong } 6335dc62b1bSWANG Cong 6345dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 6355dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 6365dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6375dc62b1bSWANG Cong int *create_cow_out) 6385dc62b1bSWANG Cong { 639853bc0abSArnd Bergmann time64_t mtime; 6405dc62b1bSWANG Cong unsigned long long size; 6415dc62b1bSWANG Cong __u32 version, align; 6425dc62b1bSWANG Cong char *backing_file; 6435dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6445dc62b1bSWANG Cong 6455dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6465dc62b1bSWANG Cong if (fd < 0) { 6475dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6485dc62b1bSWANG Cong *create_cow_out = 1; 6495dc62b1bSWANG Cong if (!openflags->w || 6505dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 6515dc62b1bSWANG Cong return fd; 6525dc62b1bSWANG Cong openflags->w = 0; 6535dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6545dc62b1bSWANG Cong if (fd < 0) 6555dc62b1bSWANG Cong return fd; 6565dc62b1bSWANG Cong } 6575dc62b1bSWANG Cong 6585dc62b1bSWANG Cong if (shared) 6595dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 6605dc62b1bSWANG Cong else { 6615dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 6625dc62b1bSWANG Cong if (err < 0) { 6635dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 6645dc62b1bSWANG Cong file, -err); 6655dc62b1bSWANG Cong goto out_close; 6665dc62b1bSWANG Cong } 6675dc62b1bSWANG Cong } 6685dc62b1bSWANG Cong 6695dc62b1bSWANG Cong /* Successful return case! */ 6705dc62b1bSWANG Cong if (backing_file_out == NULL) 6715dc62b1bSWANG Cong return fd; 6725dc62b1bSWANG Cong 6735dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 6745dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 6755dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 6765dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 6775dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 6785dc62b1bSWANG Cong goto out_close; 6795dc62b1bSWANG Cong } 6805dc62b1bSWANG Cong if (err) 6815dc62b1bSWANG Cong return fd; 6825dc62b1bSWANG Cong 6835dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 6845dc62b1bSWANG Cong file); 6855dc62b1bSWANG Cong 6865dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 6875dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 6885dc62b1bSWANG Cong mtime)) { 6895dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 6905dc62b1bSWANG Cong *backing_file_out); 6915dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 6925dc62b1bSWANG Cong sectorsize, align, &size); 6935dc62b1bSWANG Cong if (err) { 6945dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 6955dc62b1bSWANG Cong goto out_close; 6965dc62b1bSWANG Cong } 6975dc62b1bSWANG Cong } else { 6985dc62b1bSWANG Cong *backing_file_out = backing_file; 6995dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 7005dc62b1bSWANG Cong if (err) 7015dc62b1bSWANG Cong goto out_close; 7025dc62b1bSWANG Cong } 7035dc62b1bSWANG Cong 7045dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 7055dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 7065dc62b1bSWANG Cong 7075dc62b1bSWANG Cong return fd; 7085dc62b1bSWANG Cong out_close: 7095dc62b1bSWANG Cong os_close_file(fd); 7105dc62b1bSWANG Cong return err; 7115dc62b1bSWANG Cong } 7125dc62b1bSWANG Cong 7135dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 7145dc62b1bSWANG Cong struct openflags flags, 7155dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 7165dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 7175dc62b1bSWANG Cong { 7185dc62b1bSWANG Cong int err, fd; 7195dc62b1bSWANG Cong 7205dc62b1bSWANG Cong flags.c = 1; 7215dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 7225dc62b1bSWANG Cong if (fd < 0) { 7235dc62b1bSWANG Cong err = fd; 7245dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 7255dc62b1bSWANG Cong cow_file, -err); 7265dc62b1bSWANG Cong goto out; 7275dc62b1bSWANG Cong } 7285dc62b1bSWANG Cong 7295dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 7305dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 7315dc62b1bSWANG Cong data_offset_out); 7325dc62b1bSWANG Cong if (!err) 7335dc62b1bSWANG Cong return fd; 7345dc62b1bSWANG Cong os_close_file(fd); 7355dc62b1bSWANG Cong out: 7365dc62b1bSWANG Cong return err; 7375dc62b1bSWANG Cong } 7385dc62b1bSWANG Cong 7395f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7401da177e4SLinus Torvalds { 7417d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7427d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7431da177e4SLinus Torvalds return; 7441da177e4SLinus Torvalds 7457d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7467d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7477d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7481da177e4SLinus Torvalds } 7491da177e4SLinus Torvalds 7507d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 7511da177e4SLinus Torvalds { 7521da177e4SLinus Torvalds struct openflags flags; 7531da177e4SLinus Torvalds char **back_ptr; 7541da177e4SLinus Torvalds int err, create_cow, *create_ptr; 7550bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 7561da177e4SLinus Torvalds 7577d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 7581da177e4SLinus Torvalds create_cow = 0; 7597d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 7607d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 7610bf16bffSPaolo 'Blaisorblade' Giarrusso 7620bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 7637d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 7647d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 7656c29256cSJeff Dike create_ptr); 7661da177e4SLinus Torvalds 7670bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 7680bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 769a43c8316SAnton Ivanov ubd_dev->openflags, SECTOR_SIZE, PAGE_SIZE, 7707d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 7717d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 7727d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 7730bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 7741da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 7757d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 7761da177e4SLinus Torvalds } 7771da177e4SLinus Torvalds } 7781da177e4SLinus Torvalds 7790bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 7807d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 7810bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 7820bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 7831da177e4SLinus Torvalds } 7840bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 7851da177e4SLinus Torvalds 7867d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 787086fa5ffSMartin K. Petersen blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); 788f4768ffdSJeff Dike 7891da177e4SLinus Torvalds err = -ENOMEM; 790da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 7917d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 7921da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 7931da177e4SLinus Torvalds goto error; 7941da177e4SLinus Torvalds } 7951da177e4SLinus Torvalds flush_tlb_kernel_vm(); 7961da177e4SLinus Torvalds 7977d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 7987d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 7997d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 8001da177e4SLinus Torvalds if(err < 0) 8011da177e4SLinus Torvalds goto error; 8021da177e4SLinus Torvalds 8037d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 8041da177e4SLinus Torvalds flags.w = 0; 8057d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 8066c29256cSJeff Dike NULL, NULL, NULL, NULL); 8071da177e4SLinus Torvalds if(err < 0) goto error; 8087d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 8091da177e4SLinus Torvalds } 81050109b5aSAnton Ivanov if (ubd_dev->no_trim == 0) { 81150109b5aSAnton Ivanov ubd_dev->queue->limits.discard_granularity = SECTOR_SIZE; 81250109b5aSAnton Ivanov ubd_dev->queue->limits.discard_alignment = SECTOR_SIZE; 81350109b5aSAnton Ivanov blk_queue_max_discard_sectors(ubd_dev->queue, UBD_MAX_REQUEST); 81450109b5aSAnton Ivanov blk_queue_max_write_zeroes_sectors(ubd_dev->queue, UBD_MAX_REQUEST); 81550109b5aSAnton Ivanov blk_queue_flag_set(QUEUE_FLAG_DISCARD, ubd_dev->queue); 81650109b5aSAnton Ivanov } 817a43c8316SAnton Ivanov blk_queue_flag_set(QUEUE_FLAG_NONROT, ubd_dev->queue); 818dc764e50SJeff Dike return 0; 8191da177e4SLinus Torvalds error: 8207d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 821dc764e50SJeff Dike return err; 8221da177e4SLinus Torvalds } 8231da177e4SLinus Torvalds 8242e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 8252e3f5251SJeff Dike { 8268691b97bSGreg Kroah-Hartman struct ubd *ubd_dev = dev_get_drvdata(dev); 8272e3f5251SJeff Dike 8284e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 8292e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 8302e3f5251SJeff Dike } 8312e3f5251SJeff Dike 832ef3ba87cSChristopher Obbard static ssize_t serial_show(struct device *dev, 833ef3ba87cSChristopher Obbard struct device_attribute *attr, char *buf) 834ef3ba87cSChristopher Obbard { 835ef3ba87cSChristopher Obbard struct gendisk *disk = dev_to_disk(dev); 836ef3ba87cSChristopher Obbard struct ubd *ubd_dev = disk->private_data; 837ef3ba87cSChristopher Obbard 838ef3ba87cSChristopher Obbard if (!ubd_dev) 839ef3ba87cSChristopher Obbard return 0; 840ef3ba87cSChristopher Obbard 841ef3ba87cSChristopher Obbard return sprintf(buf, "%s", ubd_dev->serial); 842ef3ba87cSChristopher Obbard } 843ef3ba87cSChristopher Obbard 844ef3ba87cSChristopher Obbard static DEVICE_ATTR_RO(serial); 845ef3ba87cSChristopher Obbard 846ef3ba87cSChristopher Obbard static struct attribute *ubd_attrs[] = { 847ef3ba87cSChristopher Obbard &dev_attr_serial.attr, 848ef3ba87cSChristopher Obbard NULL, 849ef3ba87cSChristopher Obbard }; 850ef3ba87cSChristopher Obbard 851ef3ba87cSChristopher Obbard static umode_t ubd_attrs_are_visible(struct kobject *kobj, 852ef3ba87cSChristopher Obbard struct attribute *a, int n) 853ef3ba87cSChristopher Obbard { 854ef3ba87cSChristopher Obbard return a->mode; 855ef3ba87cSChristopher Obbard } 856ef3ba87cSChristopher Obbard 857ef3ba87cSChristopher Obbard static const struct attribute_group ubd_attr_group = { 858ef3ba87cSChristopher Obbard .attrs = ubd_attrs, 859ef3ba87cSChristopher Obbard .is_visible = ubd_attrs_are_visible, 860ef3ba87cSChristopher Obbard }; 861ef3ba87cSChristopher Obbard 862ef3ba87cSChristopher Obbard static const struct attribute_group *ubd_attr_groups[] = { 863ef3ba87cSChristopher Obbard &ubd_attr_group, 864ef3ba87cSChristopher Obbard NULL, 865ef3ba87cSChristopher Obbard }; 866ef3ba87cSChristopher Obbard 867*35efb594SChristoph Hellwig static void ubd_disk_register(int major, u64 size, int unit, 868*35efb594SChristoph Hellwig struct gendisk *disk) 8691da177e4SLinus Torvalds { 8701da177e4SLinus Torvalds disk->major = major; 8711da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 872*35efb594SChristoph Hellwig disk->minors = 1 << UBD_SHIFT; 8731da177e4SLinus Torvalds disk->fops = &ubd_blops; 8741da177e4SLinus Torvalds set_capacity(disk, size / 512); 8751da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 8761da177e4SLinus Torvalds 8777d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 8787d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 8792e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 8808691b97bSGreg Kroah-Hartman dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); 8817d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 8821da177e4SLinus Torvalds 8837d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 88462f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 8857eb90f7eSChristoph Hellwig device_add_disk(&ubd_devs[unit].pdev.dev, disk, ubd_attr_groups); 8861da177e4SLinus Torvalds } 8871da177e4SLinus Torvalds 888a43c8316SAnton Ivanov #define ROUND_BLOCK(n) ((n + (SECTOR_SIZE - 1)) & (-SECTOR_SIZE)) 8891da177e4SLinus Torvalds 8904e6da0feSRichard Weinberger static const struct blk_mq_ops ubd_mq_ops = { 8914e6da0feSRichard Weinberger .queue_rq = ubd_queue_rq, 8924e6da0feSRichard Weinberger }; 8934e6da0feSRichard Weinberger 894f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 8951da177e4SLinus Torvalds { 8967d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 897*35efb594SChristoph Hellwig struct gendisk *disk; 898f28169d2SJeff Dike int err = 0; 8991da177e4SLinus Torvalds 9007d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 901ec7cf783SJeff Dike goto out; 9021da177e4SLinus Torvalds 9037d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 904f28169d2SJeff Dike if(err < 0){ 905f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 90680c13749SJeff Dike goto out; 907f28169d2SJeff Dike } 9081da177e4SLinus Torvalds 9097d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 9101da177e4SLinus Torvalds 9114e6da0feSRichard Weinberger ubd_dev->tag_set.ops = &ubd_mq_ops; 9124e6da0feSRichard Weinberger ubd_dev->tag_set.queue_depth = 64; 9134e6da0feSRichard Weinberger ubd_dev->tag_set.numa_node = NUMA_NO_NODE; 9144e6da0feSRichard Weinberger ubd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; 9154e6da0feSRichard Weinberger ubd_dev->tag_set.driver_data = ubd_dev; 9164e6da0feSRichard Weinberger ubd_dev->tag_set.nr_hw_queues = 1; 917a0044bdfSJeff Dike 9184e6da0feSRichard Weinberger err = blk_mq_alloc_tag_set(&ubd_dev->tag_set); 9194e6da0feSRichard Weinberger if (err) 92080c13749SJeff Dike goto out; 9214e6da0feSRichard Weinberger 922*35efb594SChristoph Hellwig disk = blk_mq_alloc_disk(&ubd_dev->tag_set, ubd_dev); 923*35efb594SChristoph Hellwig if (IS_ERR(disk)) { 924*35efb594SChristoph Hellwig err = PTR_ERR(disk); 925aea05eb5SAnton Ivanov goto out_cleanup_tags; 92662f96cb0SJeff Dike } 927*35efb594SChristoph Hellwig ubd_dev->queue = disk->queue; 9284e6da0feSRichard Weinberger 929f935a8ceSJens Axboe blk_queue_write_cache(ubd_dev->queue, true, false); 9308a78362cSMartin K. Petersen blk_queue_max_segments(ubd_dev->queue, MAX_SG); 931fc6b6a87SGabriel Krisman Bertazi blk_queue_segment_boundary(ubd_dev->queue, PAGE_SIZE - 1); 932*35efb594SChristoph Hellwig ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, disk); 933*35efb594SChristoph Hellwig ubd_gendisk[n] = disk; 934*35efb594SChristoph Hellwig return 0; 93562f96cb0SJeff Dike 9364e6da0feSRichard Weinberger out_cleanup_tags: 9374e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 938*35efb594SChristoph Hellwig out: 939*35efb594SChristoph Hellwig return err; 9401da177e4SLinus Torvalds } 9411da177e4SLinus Torvalds 942f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 9431da177e4SLinus Torvalds { 944e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 9451da177e4SLinus Torvalds 946f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 947f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 948f28169d2SJeff Dike * were set. 949f28169d2SJeff Dike */ 950970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 9511da177e4SLinus Torvalds if (str == NULL) { 952f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 953f28169d2SJeff Dike return -ENOMEM; 9541da177e4SLinus Torvalds } 955f28169d2SJeff Dike 956f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 957f28169d2SJeff Dike if (ret) 958e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 959f28169d2SJeff Dike 960e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 961e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 962d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 963e7f6552fSPaolo 'Blaisorblade' Giarrusso } 9641da177e4SLinus Torvalds 965d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 966f28169d2SJeff Dike ret = ubd_add(n, error_out); 967e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 9687d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 969d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 9701da177e4SLinus Torvalds 971e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 972e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 973e7f6552fSPaolo 'Blaisorblade' Giarrusso 974e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 975e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 976e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 9771da177e4SLinus Torvalds } 9781da177e4SLinus Torvalds 9791da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 9801da177e4SLinus Torvalds { 9817d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 9821da177e4SLinus Torvalds int n, len = 0; 9831da177e4SLinus Torvalds 9841da177e4SLinus Torvalds n = parse_unit(&name); 9851da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 9861da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 987dc764e50SJeff Dike return -1; 9881da177e4SLinus Torvalds } 9891da177e4SLinus Torvalds 9907d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 991d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 9921da177e4SLinus Torvalds 9937d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 9941da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 9951da177e4SLinus Torvalds goto out; 9961da177e4SLinus Torvalds } 9971da177e4SLinus Torvalds 9987d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 9991da177e4SLinus Torvalds 10007d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 10011da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 10027d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 10031da177e4SLinus Torvalds } 10041da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 10051da177e4SLinus Torvalds 10061da177e4SLinus Torvalds out: 1007d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 1008dc764e50SJeff Dike return len; 10091da177e4SLinus Torvalds } 10101da177e4SLinus Torvalds 101129d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 101229d56cfeSJeff Dike { 101329d56cfeSJeff Dike int n; 101429d56cfeSJeff Dike 101529d56cfeSJeff Dike n = parse_unit(str); 101629d56cfeSJeff Dike *start_out = 0; 101729d56cfeSJeff Dike *end_out = MAX_DEV - 1; 101829d56cfeSJeff Dike return n; 101929d56cfeSJeff Dike } 102029d56cfeSJeff Dike 1021f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 10221da177e4SLinus Torvalds { 10232e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 10247d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 102529d56cfeSJeff Dike int err = -ENODEV; 10261da177e4SLinus Torvalds 1027d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10281da177e4SLinus Torvalds 10297d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 103029d56cfeSJeff Dike 10317d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 103229d56cfeSJeff Dike goto out; 103329d56cfeSJeff Dike 103429d56cfeSJeff Dike /* you cannot remove a open disk */ 103529d56cfeSJeff Dike err = -EBUSY; 10367d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 103729d56cfeSJeff Dike goto out; 103829d56cfeSJeff Dike 10391da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 1040b47d2debSJeff Dike if(disk != NULL){ 1041b47d2debSJeff Dike del_gendisk(disk); 1042*35efb594SChristoph Hellwig blk_cleanup_disk(disk); 1043b47d2debSJeff Dike } 10441da177e4SLinus Torvalds 10451da177e4SLinus Torvalds err = 0; 10462e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 10471da177e4SLinus Torvalds out: 1048d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 104929d56cfeSJeff Dike return err; 10501da177e4SLinus Torvalds } 10511da177e4SLinus Torvalds 1052f28169d2SJeff Dike /* All these are called by mconsole in process context and without 1053b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 1054f28169d2SJeff Dike */ 10551da177e4SLinus Torvalds static struct mc_device ubd_mc = { 105684f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 10571da177e4SLinus Torvalds .name = "ubd", 10581da177e4SLinus Torvalds .config = ubd_config, 10591da177e4SLinus Torvalds .get_config = ubd_get_config, 106029d56cfeSJeff Dike .id = ubd_id, 10611da177e4SLinus Torvalds .remove = ubd_remove, 10621da177e4SLinus Torvalds }; 10631da177e4SLinus Torvalds 1064d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 10651da177e4SLinus Torvalds { 10661da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 10671da177e4SLinus Torvalds return 0; 10681da177e4SLinus Torvalds } 10691da177e4SLinus Torvalds 10701da177e4SLinus Torvalds __initcall(ubd_mc_init); 10711da177e4SLinus Torvalds 1072d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1073d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1074d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1075d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1076b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1077d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1078d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1079b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1080b8831a1dSJeff Dike 1081dc764e50SJeff Dike return 0; 1082d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1083d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1084d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1085d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1086b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 10873ae5eaecSRussell King static struct platform_driver ubd_driver = { 10883ae5eaecSRussell King .driver = { 10891da177e4SLinus Torvalds .name = DRIVER_NAME, 10903ae5eaecSRussell King }, 10911da177e4SLinus Torvalds }; 10921da177e4SLinus Torvalds 1093d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 10941da177e4SLinus Torvalds { 1095f28169d2SJeff Dike char *error; 1096f28169d2SJeff Dike int i, err; 10971da177e4SLinus Torvalds 1098792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 10991da177e4SLinus Torvalds return -1; 11001da177e4SLinus Torvalds 11016da2ec56SKees Cook irq_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11026da2ec56SKees Cook sizeof(struct io_thread_req *), 1103f88f0bdfSAnton Ivanov GFP_KERNEL 1104f88f0bdfSAnton Ivanov ); 1105f88f0bdfSAnton Ivanov irq_remainder = 0; 1106f88f0bdfSAnton Ivanov 1107f88f0bdfSAnton Ivanov if (irq_req_buffer == NULL) { 1108f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1109f88f0bdfSAnton Ivanov return -1; 1110f88f0bdfSAnton Ivanov } 11116da2ec56SKees Cook io_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11126da2ec56SKees Cook sizeof(struct io_thread_req *), 1113f88f0bdfSAnton Ivanov GFP_KERNEL 1114f88f0bdfSAnton Ivanov ); 1115f88f0bdfSAnton Ivanov 1116f88f0bdfSAnton Ivanov io_remainder = 0; 1117f88f0bdfSAnton Ivanov 1118f88f0bdfSAnton Ivanov if (io_req_buffer == NULL) { 1119f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1120f88f0bdfSAnton Ivanov return -1; 1121f88f0bdfSAnton Ivanov } 11223ae5eaecSRussell King platform_driver_register(&ubd_driver); 1123b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1124f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1125f28169d2SJeff Dike err = ubd_add(i, &error); 1126f28169d2SJeff Dike if(err) 1127f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1128f28169d2SJeff Dike "%s\n", i, error); 1129f28169d2SJeff Dike } 1130b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 11311da177e4SLinus Torvalds return 0; 11321da177e4SLinus Torvalds } 11331da177e4SLinus Torvalds 11341da177e4SLinus Torvalds late_initcall(ubd_init); 11351da177e4SLinus Torvalds 1136d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 113791acb21fSJeff Dike unsigned long stack; 113891acb21fSJeff Dike int err; 113991acb21fSJeff Dike 114091acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 114191acb21fSJeff Dike if(global_openflags.s){ 114291acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 114391acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 114491acb21fSJeff Dike * enough. So use anyway the io thread. */ 114591acb21fSJeff Dike } 11462fcb4090SJohannes Berg stack = alloc_stack(0, 0); 114791acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 114891acb21fSJeff Dike &thread_fd); 114991acb21fSJeff Dike if(io_pid < 0){ 115091acb21fSJeff Dike printk(KERN_ERR 115191acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 115291acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 115391acb21fSJeff Dike io_pid = -1; 1154dc764e50SJeff Dike return 0; 115591acb21fSJeff Dike } 115691acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 1157c0b79a90SYong Zhang 0, "ubd", ubd_devs); 115836d46a59SJohannes Berg if(err < 0) 115991acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1160f4c57a78SJeff Dike return 0; 116191acb21fSJeff Dike } 116291acb21fSJeff Dike 116391acb21fSJeff Dike device_initcall(ubd_driver_init); 116491acb21fSJeff Dike 1165a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 11661da177e4SLinus Torvalds { 1167a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 11687d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 11691da177e4SLinus Torvalds int err = 0; 11701da177e4SLinus Torvalds 11719a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 11727d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 11737d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 11741da177e4SLinus Torvalds if(err){ 11751da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 11767d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 11771da177e4SLinus Torvalds goto out; 11781da177e4SLinus Torvalds } 11791da177e4SLinus Torvalds } 11807d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 11817d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 11822c49be99SPaolo 'Blaisorblade' Giarrusso 11832c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 11842c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1185a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 11865f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 11871da177e4SLinus Torvalds err = -EROFS; 11882c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 11891da177e4SLinus Torvalds out: 11909a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 1191dc764e50SJeff Dike return err; 11921da177e4SLinus Torvalds } 11931da177e4SLinus Torvalds 1194db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode) 11951da177e4SLinus Torvalds { 11967d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 11971da177e4SLinus Torvalds 11989a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 11997d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 12005f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 12019a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 12021da177e4SLinus Torvalds } 12031da177e4SLinus Torvalds 120491acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 120591acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 120691acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 120791acb21fSJeff Dike __u64 bitmap_len) 12081da177e4SLinus Torvalds { 1209a43c8316SAnton Ivanov __u64 sector = io_offset >> SECTOR_SHIFT; 121091acb21fSJeff Dike int i, update_bitmap = 0; 12111da177e4SLinus Torvalds 1212a43c8316SAnton Ivanov for (i = 0; i < length >> SECTOR_SHIFT; i++) { 121391acb21fSJeff Dike if(cow_mask != NULL) 121491acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 121591acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 121609ace81cSJeff Dike continue; 12171da177e4SLinus Torvalds 121891acb21fSJeff Dike update_bitmap = 1; 121991acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 12201da177e4SLinus Torvalds } 122191acb21fSJeff Dike 122291acb21fSJeff Dike if(!update_bitmap) 122391acb21fSJeff Dike return; 122491acb21fSJeff Dike 122591acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 122691acb21fSJeff Dike 122791acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 122891acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 122991acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 123091acb21fSJeff Dike * for the original diagnosis. 123191acb21fSJeff Dike */ 12326d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 12336d074242SJiri Olsa sizeof(unsigned long)) - 1)) 123491acb21fSJeff Dike (*cow_offset)--; 123591acb21fSJeff Dike 123691acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 123791acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 123891acb21fSJeff Dike 123991acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 124091acb21fSJeff Dike *cow_offset += bitmap_offset; 124191acb21fSJeff Dike } 124291acb21fSJeff Dike 1243fc6b6a87SGabriel Krisman Bertazi static void cowify_req(struct io_thread_req *req, struct io_desc *segment, 1244fc6b6a87SGabriel Krisman Bertazi unsigned long offset, unsigned long *bitmap, 124591acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 124691acb21fSJeff Dike { 1247fc6b6a87SGabriel Krisman Bertazi __u64 sector = offset >> SECTOR_SHIFT; 124891acb21fSJeff Dike int i; 124991acb21fSJeff Dike 1250fc6b6a87SGabriel Krisman Bertazi if (segment->length > (sizeof(segment->sector_mask) * 8) << SECTOR_SHIFT) 125191acb21fSJeff Dike panic("Operation too long"); 125291acb21fSJeff Dike 1253a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_READ) { 1254fc6b6a87SGabriel Krisman Bertazi for (i = 0; i < segment->length >> SECTOR_SHIFT; i++) { 125591acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 125691acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 1257fc6b6a87SGabriel Krisman Bertazi &segment->sector_mask); 125891acb21fSJeff Dike } 1259fc6b6a87SGabriel Krisman Bertazi } else { 1260fc6b6a87SGabriel Krisman Bertazi cowify_bitmap(offset, segment->length, &segment->sector_mask, 1261fc6b6a87SGabriel Krisman Bertazi &segment->cow_offset, bitmap, bitmap_offset, 1262fc6b6a87SGabriel Krisman Bertazi segment->bitmap_words, bitmap_len); 126391acb21fSJeff Dike } 12641da177e4SLinus Torvalds } 12651da177e4SLinus Torvalds 1266fc6b6a87SGabriel Krisman Bertazi static void ubd_map_req(struct ubd *dev, struct io_thread_req *io_req, 1267fc6b6a87SGabriel Krisman Bertazi struct request *req) 12681da177e4SLinus Torvalds { 1269fc6b6a87SGabriel Krisman Bertazi struct bio_vec bvec; 1270fc6b6a87SGabriel Krisman Bertazi struct req_iterator iter; 1271fc6b6a87SGabriel Krisman Bertazi int i = 0; 1272fc6b6a87SGabriel Krisman Bertazi unsigned long byte_offset = io_req->offset; 1273fc6b6a87SGabriel Krisman Bertazi int op = req_op(req); 1274ecb0a83eSChristoph Hellwig 1275fc6b6a87SGabriel Krisman Bertazi if (op == REQ_OP_WRITE_ZEROES || op == REQ_OP_DISCARD) { 1276fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[0].buffer = NULL; 1277fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[0].length = blk_rq_bytes(req); 1278fc6b6a87SGabriel Krisman Bertazi } else { 1279fc6b6a87SGabriel Krisman Bertazi rq_for_each_segment(bvec, req, iter) { 1280fc6b6a87SGabriel Krisman Bertazi BUG_ON(i >= io_req->desc_cnt); 1281fc6b6a87SGabriel Krisman Bertazi 1282fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].buffer = 1283fc6b6a87SGabriel Krisman Bertazi page_address(bvec.bv_page) + bvec.bv_offset; 1284fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].length = bvec.bv_len; 1285fc6b6a87SGabriel Krisman Bertazi i++; 1286fc6b6a87SGabriel Krisman Bertazi } 1287fc6b6a87SGabriel Krisman Bertazi } 1288fc6b6a87SGabriel Krisman Bertazi 1289fc6b6a87SGabriel Krisman Bertazi if (dev->cow.file) { 1290fc6b6a87SGabriel Krisman Bertazi for (i = 0; i < io_req->desc_cnt; i++) { 1291fc6b6a87SGabriel Krisman Bertazi cowify_req(io_req, &io_req->io_desc[i], byte_offset, 1292fc6b6a87SGabriel Krisman Bertazi dev->cow.bitmap, dev->cow.bitmap_offset, 1293fc6b6a87SGabriel Krisman Bertazi dev->cow.bitmap_len); 1294fc6b6a87SGabriel Krisman Bertazi byte_offset += io_req->io_desc[i].length; 1295fc6b6a87SGabriel Krisman Bertazi } 1296fc6b6a87SGabriel Krisman Bertazi 1297fc6b6a87SGabriel Krisman Bertazi } 1298fc6b6a87SGabriel Krisman Bertazi } 1299fc6b6a87SGabriel Krisman Bertazi 1300fc6b6a87SGabriel Krisman Bertazi static struct io_thread_req *ubd_alloc_req(struct ubd *dev, struct request *req, 1301fc6b6a87SGabriel Krisman Bertazi int desc_cnt) 1302fc6b6a87SGabriel Krisman Bertazi { 1303fc6b6a87SGabriel Krisman Bertazi struct io_thread_req *io_req; 1304fc6b6a87SGabriel Krisman Bertazi int i; 1305fc6b6a87SGabriel Krisman Bertazi 1306fc6b6a87SGabriel Krisman Bertazi io_req = kmalloc(sizeof(*io_req) + 1307fc6b6a87SGabriel Krisman Bertazi (desc_cnt * sizeof(struct io_desc)), 1308fc6b6a87SGabriel Krisman Bertazi GFP_ATOMIC); 1309ecb0a83eSChristoph Hellwig if (!io_req) 1310fc6b6a87SGabriel Krisman Bertazi return NULL; 131191acb21fSJeff Dike 131262f96cb0SJeff Dike io_req->req = req; 1313ecb0a83eSChristoph Hellwig if (dev->cow.file) 1314ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->cow.fd; 1315ecb0a83eSChristoph Hellwig else 1316ecb0a83eSChristoph Hellwig io_req->fds[0] = dev->fd; 13170033dfd9SAnton Ivanov io_req->error = 0; 131853766defSAnton Ivanov io_req->sectorsize = SECTOR_SIZE; 1319ecb0a83eSChristoph Hellwig io_req->fds[1] = dev->fd; 1320fc6b6a87SGabriel Krisman Bertazi io_req->offset = (u64) blk_rq_pos(req) << SECTOR_SHIFT; 13211da177e4SLinus Torvalds io_req->offsets[0] = 0; 1322ecb0a83eSChristoph Hellwig io_req->offsets[1] = dev->cow.data_offset; 13231da177e4SLinus Torvalds 1324fc6b6a87SGabriel Krisman Bertazi for (i = 0 ; i < desc_cnt; i++) { 1325fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].sector_mask = 0; 1326fc6b6a87SGabriel Krisman Bertazi io_req->io_desc[i].cow_offset = -1; 1327fc6b6a87SGabriel Krisman Bertazi } 1328fc6b6a87SGabriel Krisman Bertazi 1329fc6b6a87SGabriel Krisman Bertazi return io_req; 1330fc6b6a87SGabriel Krisman Bertazi } 1331fc6b6a87SGabriel Krisman Bertazi 1332fc6b6a87SGabriel Krisman Bertazi static int ubd_submit_request(struct ubd *dev, struct request *req) 1333fc6b6a87SGabriel Krisman Bertazi { 1334fc6b6a87SGabriel Krisman Bertazi int segs = 0; 1335fc6b6a87SGabriel Krisman Bertazi struct io_thread_req *io_req; 1336fc6b6a87SGabriel Krisman Bertazi int ret; 1337fc6b6a87SGabriel Krisman Bertazi int op = req_op(req); 1338fc6b6a87SGabriel Krisman Bertazi 1339fc6b6a87SGabriel Krisman Bertazi if (op == REQ_OP_FLUSH) 1340fc6b6a87SGabriel Krisman Bertazi segs = 0; 1341fc6b6a87SGabriel Krisman Bertazi else if (op == REQ_OP_WRITE_ZEROES || op == REQ_OP_DISCARD) 1342fc6b6a87SGabriel Krisman Bertazi segs = 1; 1343fc6b6a87SGabriel Krisman Bertazi else 1344fc6b6a87SGabriel Krisman Bertazi segs = blk_rq_nr_phys_segments(req); 1345fc6b6a87SGabriel Krisman Bertazi 1346fc6b6a87SGabriel Krisman Bertazi io_req = ubd_alloc_req(dev, req, segs); 1347fc6b6a87SGabriel Krisman Bertazi if (!io_req) 1348fc6b6a87SGabriel Krisman Bertazi return -ENOMEM; 1349fc6b6a87SGabriel Krisman Bertazi 1350fc6b6a87SGabriel Krisman Bertazi io_req->desc_cnt = segs; 1351fc6b6a87SGabriel Krisman Bertazi if (segs) 1352fc6b6a87SGabriel Krisman Bertazi ubd_map_req(dev, io_req, req); 13531da177e4SLinus Torvalds 1354ecb0a83eSChristoph Hellwig ret = os_write_file(thread_fd, &io_req, sizeof(io_req)); 1355ecb0a83eSChristoph Hellwig if (ret != sizeof(io_req)) { 1356ecb0a83eSChristoph Hellwig if (ret != -EAGAIN) 1357ecb0a83eSChristoph Hellwig pr_err("write to io thread failed: %d\n", -ret); 1358bc1d72e7SRichard Weinberger kfree(io_req); 1359bc1d72e7SRichard Weinberger } 1360ecb0a83eSChristoph Hellwig return ret; 1361bc1d72e7SRichard Weinberger } 1362bc1d72e7SRichard Weinberger 13634e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 13644e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd) 13651da177e4SLinus Torvalds { 13666961cd4dSJens Axboe struct ubd *ubd_dev = hctx->queue->queuedata; 13674e6da0feSRichard Weinberger struct request *req = bd->rq; 136853766defSAnton Ivanov int ret = 0, res = BLK_STS_OK; 13691da177e4SLinus Torvalds 13704e6da0feSRichard Weinberger blk_mq_start_request(req); 1371a0044bdfSJeff Dike 13726961cd4dSJens Axboe spin_lock_irq(&ubd_dev->lock); 13736961cd4dSJens Axboe 137453766defSAnton Ivanov switch (req_op(req)) { 137553766defSAnton Ivanov case REQ_OP_FLUSH: 137653766defSAnton Ivanov case REQ_OP_READ: 137753766defSAnton Ivanov case REQ_OP_WRITE: 137850109b5aSAnton Ivanov case REQ_OP_DISCARD: 137950109b5aSAnton Ivanov case REQ_OP_WRITE_ZEROES: 1380fc6b6a87SGabriel Krisman Bertazi ret = ubd_submit_request(ubd_dev, req); 138150109b5aSAnton Ivanov break; 138253766defSAnton Ivanov default: 138353766defSAnton Ivanov WARN_ON_ONCE(1); 138453766defSAnton Ivanov res = BLK_STS_NOTSUPP; 138553766defSAnton Ivanov } 1386ecb0a83eSChristoph Hellwig 13876961cd4dSJens Axboe spin_unlock_irq(&ubd_dev->lock); 13886961cd4dSJens Axboe 1389d848074bSAnton Ivanov if (ret < 0) { 1390d848074bSAnton Ivanov if (ret == -ENOMEM) 1391d848074bSAnton Ivanov res = BLK_STS_RESOURCE; 1392d848074bSAnton Ivanov else 1393d848074bSAnton Ivanov res = BLK_STS_DEV_RESOURCE; 1394d848074bSAnton Ivanov } 13956961cd4dSJens Axboe 139653766defSAnton Ivanov return res; 139791acb21fSJeff Dike } 13984e6da0feSRichard Weinberger 1399a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1400a885c8c4SChristoph Hellwig { 14017d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1402a885c8c4SChristoph Hellwig 1403a885c8c4SChristoph Hellwig geo->heads = 128; 1404a885c8c4SChristoph Hellwig geo->sectors = 32; 14057d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1406a885c8c4SChristoph Hellwig return 0; 1407a885c8c4SChristoph Hellwig } 1408a885c8c4SChristoph Hellwig 1409a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 14101da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 14111da177e4SLinus Torvalds { 1412a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 141373855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 14141da177e4SLinus Torvalds 14151da177e4SLinus Torvalds switch (cmd) { 14161da177e4SLinus Torvalds struct cdrom_volctrl volume; 14171da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 141873855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 141973855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 142073855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 142173855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 14221da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 14231da177e4SLinus Torvalds sizeof(ubd_id))) 1424dc764e50SJeff Dike return -EFAULT; 1425dc764e50SJeff Dike return 0; 14261da177e4SLinus Torvalds 14271da177e4SLinus Torvalds case CDROMVOLREAD: 14281da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1429dc764e50SJeff Dike return -EFAULT; 14301da177e4SLinus Torvalds volume.channel0 = 255; 14311da177e4SLinus Torvalds volume.channel1 = 255; 14321da177e4SLinus Torvalds volume.channel2 = 255; 14331da177e4SLinus Torvalds volume.channel3 = 255; 14341da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1435dc764e50SJeff Dike return -EFAULT; 1436dc764e50SJeff Dike return 0; 14371da177e4SLinus Torvalds } 1438dc764e50SJeff Dike return -EINVAL; 14391da177e4SLinus Torvalds } 14401da177e4SLinus Torvalds 1441a43c8316SAnton Ivanov static int map_error(int error_code) 1442a43c8316SAnton Ivanov { 1443a43c8316SAnton Ivanov switch (error_code) { 1444a43c8316SAnton Ivanov case 0: 1445a43c8316SAnton Ivanov return BLK_STS_OK; 1446a43c8316SAnton Ivanov case ENOSYS: 1447a43c8316SAnton Ivanov case EOPNOTSUPP: 1448a43c8316SAnton Ivanov return BLK_STS_NOTSUPP; 1449a43c8316SAnton Ivanov case ENOSPC: 1450a43c8316SAnton Ivanov return BLK_STS_NOSPC; 1451a43c8316SAnton Ivanov } 1452a43c8316SAnton Ivanov return BLK_STS_IOERR; 1453a43c8316SAnton Ivanov } 1454a43c8316SAnton Ivanov 1455a41421edSAnton Ivanov /* 1456a41421edSAnton Ivanov * Everything from here onwards *IS NOT PART OF THE KERNEL* 1457a41421edSAnton Ivanov * 1458a41421edSAnton Ivanov * The following functions are part of UML hypervisor code. 1459a41421edSAnton Ivanov * All functions from here onwards are executed as a helper 1460a41421edSAnton Ivanov * thread and are not allowed to execute any kernel functions. 1461a41421edSAnton Ivanov * 1462a41421edSAnton Ivanov * Any communication must occur strictly via shared memory and IPC. 1463a41421edSAnton Ivanov * 1464a41421edSAnton Ivanov * Do not add printks, locks, kernel memory operations, etc - it 1465a41421edSAnton Ivanov * will result in unpredictable behaviour and/or crashes. 1466a41421edSAnton Ivanov */ 1467a41421edSAnton Ivanov 1468fc6b6a87SGabriel Krisman Bertazi static int update_bitmap(struct io_thread_req *req, struct io_desc *segment) 14691da177e4SLinus Torvalds { 147091acb21fSJeff Dike int n; 147191acb21fSJeff Dike 1472fc6b6a87SGabriel Krisman Bertazi if (segment->cow_offset == -1) 1473a43c8316SAnton Ivanov return map_error(0); 147491acb21fSJeff Dike 1475fc6b6a87SGabriel Krisman Bertazi n = os_pwrite_file(req->fds[1], &segment->bitmap_words, 1476fc6b6a87SGabriel Krisman Bertazi sizeof(segment->bitmap_words), segment->cow_offset); 1477fc6b6a87SGabriel Krisman Bertazi if (n != sizeof(segment->bitmap_words)) 1478a43c8316SAnton Ivanov return map_error(-n); 147991acb21fSJeff Dike 1480a43c8316SAnton Ivanov return map_error(0); 148191acb21fSJeff Dike } 148291acb21fSJeff Dike 1483fc6b6a87SGabriel Krisman Bertazi static void do_io(struct io_thread_req *req, struct io_desc *desc) 148491acb21fSJeff Dike { 148550109b5aSAnton Ivanov char *buf = NULL; 148691acb21fSJeff Dike unsigned long len; 148791acb21fSJeff Dike int n, nsectors, start, end, bit; 14881da177e4SLinus Torvalds __u64 off; 14891da177e4SLinus Torvalds 149050109b5aSAnton Ivanov /* FLUSH is really a special case, we cannot "case" it with others */ 149150109b5aSAnton Ivanov 1492a43c8316SAnton Ivanov if (req_op(req->req) == REQ_OP_FLUSH) { 1493805f11a0SRichard Weinberger /* fds[0] is always either the rw image or our cow file */ 1494a41421edSAnton Ivanov req->error = map_error(-os_sync_file(req->fds[0])); 1495805f11a0SRichard Weinberger return; 1496805f11a0SRichard Weinberger } 1497805f11a0SRichard Weinberger 1498fc6b6a87SGabriel Krisman Bertazi nsectors = desc->length / req->sectorsize; 14991da177e4SLinus Torvalds start = 0; 15001da177e4SLinus Torvalds do { 1501fc6b6a87SGabriel Krisman Bertazi bit = ubd_test_bit(start, (unsigned char *) &desc->sector_mask); 15021da177e4SLinus Torvalds end = start; 15031da177e4SLinus Torvalds while((end < nsectors) && 1504fc6b6a87SGabriel Krisman Bertazi (ubd_test_bit(end, (unsigned char *) &desc->sector_mask) == bit)) 15051da177e4SLinus Torvalds end++; 15061da177e4SLinus Torvalds 150791acb21fSJeff Dike off = req->offset + req->offsets[bit] + 15081da177e4SLinus Torvalds start * req->sectorsize; 15091da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 1510fc6b6a87SGabriel Krisman Bertazi if (desc->buffer != NULL) 1511fc6b6a87SGabriel Krisman Bertazi buf = &desc->buffer[start * req->sectorsize]; 15121da177e4SLinus Torvalds 151350109b5aSAnton Ivanov switch (req_op(req->req)) { 151450109b5aSAnton Ivanov case REQ_OP_READ: 151591acb21fSJeff Dike n = 0; 151691acb21fSJeff Dike do { 151791acb21fSJeff Dike buf = &buf[n]; 151891acb21fSJeff Dike len -= n; 15198c6157b6SAnton Ivanov n = os_pread_file(req->fds[bit], buf, len, off); 152091acb21fSJeff Dike if (n < 0) { 1521a43c8316SAnton Ivanov req->error = map_error(-n); 15221da177e4SLinus Torvalds return; 15231da177e4SLinus Torvalds } 152491acb21fSJeff Dike } while((n < len) && (n != 0)); 152591acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 152650109b5aSAnton Ivanov break; 152750109b5aSAnton Ivanov case REQ_OP_WRITE: 15288c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[bit], buf, len, off); 152991acb21fSJeff Dike if(n != len){ 1530a43c8316SAnton Ivanov req->error = map_error(-n); 153191acb21fSJeff Dike return; 153291acb21fSJeff Dike } 153350109b5aSAnton Ivanov break; 153450109b5aSAnton Ivanov case REQ_OP_DISCARD: 153550109b5aSAnton Ivanov case REQ_OP_WRITE_ZEROES: 153650109b5aSAnton Ivanov n = os_falloc_punch(req->fds[bit], off, len); 153750109b5aSAnton Ivanov if (n) { 153850109b5aSAnton Ivanov req->error = map_error(-n); 153950109b5aSAnton Ivanov return; 154050109b5aSAnton Ivanov } 154150109b5aSAnton Ivanov break; 154250109b5aSAnton Ivanov default: 154350109b5aSAnton Ivanov WARN_ON_ONCE(1); 154450109b5aSAnton Ivanov req->error = BLK_STS_NOTSUPP; 154550109b5aSAnton Ivanov return; 154691acb21fSJeff Dike } 15471da177e4SLinus Torvalds 15481da177e4SLinus Torvalds start = end; 15491da177e4SLinus Torvalds } while(start < nsectors); 155091acb21fSJeff Dike 1551fc6b6a87SGabriel Krisman Bertazi req->offset += len; 1552fc6b6a87SGabriel Krisman Bertazi req->error = update_bitmap(req, desc); 15531da177e4SLinus Torvalds } 155491acb21fSJeff Dike 155591acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 155691acb21fSJeff Dike * from ubd_init, which is an initcall. 155791acb21fSJeff Dike */ 155891acb21fSJeff Dike int kernel_fd = -1; 155991acb21fSJeff Dike 1560d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1561d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 156291acb21fSJeff Dike 156391acb21fSJeff Dike int io_thread(void *arg) 156491acb21fSJeff Dike { 1565f88f0bdfSAnton Ivanov int n, count, written, res; 156691acb21fSJeff Dike 156791d44ff8SRichard Weinberger os_fix_helper_signals(); 156891d44ff8SRichard Weinberger 156991acb21fSJeff Dike while(1){ 1570f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 1571f88f0bdfSAnton Ivanov kernel_fd, 1572f88f0bdfSAnton Ivanov io_req_buffer, 1573f88f0bdfSAnton Ivanov &io_remainder, 1574f88f0bdfSAnton Ivanov &io_remainder_size, 1575f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 1576f88f0bdfSAnton Ivanov ); 1577e355b2f5SGabriel Krisman Bertazi if (n <= 0) { 1578e355b2f5SGabriel Krisman Bertazi if (n == -EAGAIN) 1579f88f0bdfSAnton Ivanov ubd_read_poll(-1); 1580e355b2f5SGabriel Krisman Bertazi 1581f88f0bdfSAnton Ivanov continue; 1582f88f0bdfSAnton Ivanov } 1583f88f0bdfSAnton Ivanov 1584f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 1585fc6b6a87SGabriel Krisman Bertazi struct io_thread_req *req = (*io_req_buffer)[count]; 1586fc6b6a87SGabriel Krisman Bertazi int i; 1587fc6b6a87SGabriel Krisman Bertazi 1588f88f0bdfSAnton Ivanov io_count++; 1589fc6b6a87SGabriel Krisman Bertazi for (i = 0; !req->error && i < req->desc_cnt; i++) 1590fc6b6a87SGabriel Krisman Bertazi do_io(req, &(req->io_desc[i])); 1591fc6b6a87SGabriel Krisman Bertazi 1592f88f0bdfSAnton Ivanov } 1593f88f0bdfSAnton Ivanov 1594f88f0bdfSAnton Ivanov written = 0; 1595f88f0bdfSAnton Ivanov 1596f88f0bdfSAnton Ivanov do { 15976e682d53SGabriel Krisman Bertazi res = os_write_file(kernel_fd, 15986e682d53SGabriel Krisman Bertazi ((char *) io_req_buffer) + written, 15996e682d53SGabriel Krisman Bertazi n - written); 1600ff6a1798SAnton Ivanov if (res >= 0) { 1601f88f0bdfSAnton Ivanov written += res; 160291acb21fSJeff Dike } 1603f88f0bdfSAnton Ivanov if (written < n) { 1604f88f0bdfSAnton Ivanov ubd_write_poll(-1); 1605f88f0bdfSAnton Ivanov } 1606f88f0bdfSAnton Ivanov } while (written < n); 160791acb21fSJeff Dike } 160891acb21fSJeff Dike 16091b57e9c2SJeff Dike return 0; 16101b57e9c2SJeff Dike } 1611