11da177e4SLinus Torvalds /* 2f88f0bdfSAnton Ivanov * Copyright (C) 2015-2016 Anton Ivanov (aivanov@brocade.com) 31da177e4SLinus Torvalds * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) 41da177e4SLinus Torvalds * Licensed under the GPL 51da177e4SLinus Torvalds */ 61da177e4SLinus Torvalds 71da177e4SLinus Torvalds /* 2001-09-28...2002-04-17 81da177e4SLinus Torvalds * Partition stuff by James_McMechan@hotmail.com 91da177e4SLinus Torvalds * old style ubd by setting UBD_SHIFT to 0 101da177e4SLinus Torvalds * 2002-09-27...2002-10-18 massive tinkering for 2.5 111da177e4SLinus Torvalds * partitions have changed in 2.5 121da177e4SLinus Torvalds * 2003-01-29 more tinkering for 2.5.59-1 131da177e4SLinus Torvalds * This should now address the sysfs problems and has 141da177e4SLinus Torvalds * the symlink for devfs to allow for booting with 151da177e4SLinus Torvalds * the common /dev/ubd/discX/... names rather than 161da177e4SLinus Torvalds * only /dev/ubdN/discN this version also has lots of 171da177e4SLinus Torvalds * clean ups preparing for ubd-many. 181da177e4SLinus Torvalds * James McMechan 191da177e4SLinus Torvalds */ 201da177e4SLinus Torvalds 211da177e4SLinus Torvalds #define UBD_SHIFT 4 221da177e4SLinus Torvalds 238ea3c06aSAl Viro #include <linux/module.h> 248ea3c06aSAl Viro #include <linux/init.h> 258ea3c06aSAl Viro #include <linux/blkdev.h> 264e6da0feSRichard Weinberger #include <linux/blk-mq.h> 278ea3c06aSAl Viro #include <linux/ata.h> 288ea3c06aSAl Viro #include <linux/hdreg.h> 298ea3c06aSAl Viro #include <linux/cdrom.h> 308ea3c06aSAl Viro #include <linux/proc_fs.h> 318ea3c06aSAl Viro #include <linux/seq_file.h> 328ea3c06aSAl Viro #include <linux/ctype.h> 338ea3c06aSAl Viro #include <linux/slab.h> 348ea3c06aSAl Viro #include <linux/vmalloc.h> 358ea3c06aSAl Viro #include <linux/platform_device.h> 368ea3c06aSAl Viro #include <linux/scatterlist.h> 378ea3c06aSAl Viro #include <asm/tlbflush.h> 3837185b33SAl Viro #include <kern_util.h> 391da177e4SLinus Torvalds #include "mconsole_kern.h" 4037185b33SAl Viro #include <init.h> 4137185b33SAl Viro #include <irq_kern.h> 428ea3c06aSAl Viro #include "ubd.h" 4337185b33SAl Viro #include <os.h> 441da177e4SLinus Torvalds #include "cow.h" 451da177e4SLinus Torvalds 46805f11a0SRichard Weinberger enum ubd_req { UBD_READ, UBD_WRITE, UBD_FLUSH }; 471da177e4SLinus Torvalds 481da177e4SLinus Torvalds struct io_thread_req { 4962f96cb0SJeff Dike struct request *req; 5091acb21fSJeff Dike enum ubd_req op; 511da177e4SLinus Torvalds int fds[2]; 521da177e4SLinus Torvalds unsigned long offsets[2]; 531da177e4SLinus Torvalds unsigned long long offset; 541da177e4SLinus Torvalds unsigned long length; 551da177e4SLinus Torvalds char *buffer; 561da177e4SLinus Torvalds int sectorsize; 5791acb21fSJeff Dike unsigned long sector_mask; 5891acb21fSJeff Dike unsigned long long cow_offset; 5991acb21fSJeff Dike unsigned long bitmap_words[2]; 601da177e4SLinus Torvalds int error; 611da177e4SLinus Torvalds }; 621da177e4SLinus Torvalds 63f88f0bdfSAnton Ivanov 64f88f0bdfSAnton Ivanov static struct io_thread_req * (*irq_req_buffer)[]; 65f88f0bdfSAnton Ivanov static struct io_thread_req *irq_remainder; 66f88f0bdfSAnton Ivanov static int irq_remainder_size; 67f88f0bdfSAnton Ivanov 68f88f0bdfSAnton Ivanov static struct io_thread_req * (*io_req_buffer)[]; 69f88f0bdfSAnton Ivanov static struct io_thread_req *io_remainder; 70f88f0bdfSAnton Ivanov static int io_remainder_size; 71f88f0bdfSAnton Ivanov 72f88f0bdfSAnton Ivanov 73f88f0bdfSAnton Ivanov 7491acb21fSJeff Dike static inline int ubd_test_bit(__u64 bit, unsigned char *data) 751da177e4SLinus Torvalds { 761da177e4SLinus Torvalds __u64 n; 771da177e4SLinus Torvalds int bits, off; 781da177e4SLinus Torvalds 7991acb21fSJeff Dike bits = sizeof(data[0]) * 8; 801da177e4SLinus Torvalds n = bit / bits; 811da177e4SLinus Torvalds off = bit % bits; 82dc764e50SJeff Dike return (data[n] & (1 << off)) != 0; 831da177e4SLinus Torvalds } 841da177e4SLinus Torvalds 8591acb21fSJeff Dike static inline void ubd_set_bit(__u64 bit, unsigned char *data) 861da177e4SLinus Torvalds { 871da177e4SLinus Torvalds __u64 n; 881da177e4SLinus Torvalds int bits, off; 891da177e4SLinus Torvalds 9091acb21fSJeff Dike bits = sizeof(data[0]) * 8; 911da177e4SLinus Torvalds n = bit / bits; 921da177e4SLinus Torvalds off = bit % bits; 9391acb21fSJeff Dike data[n] |= (1 << off); 941da177e4SLinus Torvalds } 951da177e4SLinus Torvalds /*End stuff from ubd_user.h*/ 961da177e4SLinus Torvalds 971da177e4SLinus Torvalds #define DRIVER_NAME "uml-blkdev" 981da177e4SLinus Torvalds 99d7fb2c38SPaolo 'Blaisorblade' Giarrusso static DEFINE_MUTEX(ubd_lock); 1009a181c58SArnd Bergmann static DEFINE_MUTEX(ubd_mutex); /* replaces BKL, might not be needed */ 1011da177e4SLinus Torvalds 102a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode); 103db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode); 104a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 1051da177e4SLinus Torvalds unsigned int cmd, unsigned long arg); 106a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); 1071da177e4SLinus Torvalds 10897d88ac8SPaolo 'Blaisorblade' Giarrusso #define MAX_DEV (16) 1091da177e4SLinus Torvalds 11083d5cde4SAlexey Dobriyan static const struct block_device_operations ubd_blops = { 1111da177e4SLinus Torvalds .owner = THIS_MODULE, 112a625c998SAl Viro .open = ubd_open, 113a625c998SAl Viro .release = ubd_release, 114a625c998SAl Viro .ioctl = ubd_ioctl, 115a885c8c4SChristoph Hellwig .getgeo = ubd_getgeo, 1161da177e4SLinus Torvalds }; 1171da177e4SLinus Torvalds 1181da177e4SLinus Torvalds /* Protected by ubd_lock */ 119792dd4fcSChristoph Hellwig static int fake_major = UBD_MAJOR; 1201da177e4SLinus Torvalds static struct gendisk *ubd_gendisk[MAX_DEV]; 1211da177e4SLinus Torvalds static struct gendisk *fake_gendisk[MAX_DEV]; 1221da177e4SLinus Torvalds 1231da177e4SLinus Torvalds #ifdef CONFIG_BLK_DEV_UBD_SYNC 1241da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ 1251da177e4SLinus Torvalds .cl = 1 }) 1261da177e4SLinus Torvalds #else 1271da177e4SLinus Torvalds #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ 1281da177e4SLinus Torvalds .cl = 1 }) 1291da177e4SLinus Torvalds #endif 1301da177e4SLinus Torvalds static struct openflags global_openflags = OPEN_FLAGS; 1311da177e4SLinus Torvalds 1321da177e4SLinus Torvalds struct cow { 1332a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file name */ 1341da177e4SLinus Torvalds char *file; 1352a9d32f6SPaolo 'Blaisorblade' Giarrusso /* backing file fd */ 1361da177e4SLinus Torvalds int fd; 1371da177e4SLinus Torvalds unsigned long *bitmap; 1381da177e4SLinus Torvalds unsigned long bitmap_len; 1391da177e4SLinus Torvalds int bitmap_offset; 1401da177e4SLinus Torvalds int data_offset; 1411da177e4SLinus Torvalds }; 1421da177e4SLinus Torvalds 143a0044bdfSJeff Dike #define MAX_SG 64 144a0044bdfSJeff Dike 1451da177e4SLinus Torvalds struct ubd { 1462a9d32f6SPaolo 'Blaisorblade' Giarrusso /* name (and fd, below) of the file opened for writing, either the 1472a9d32f6SPaolo 'Blaisorblade' Giarrusso * backing or the cow file. */ 1481da177e4SLinus Torvalds char *file; 1491da177e4SLinus Torvalds int count; 1501da177e4SLinus Torvalds int fd; 1511da177e4SLinus Torvalds __u64 size; 1521da177e4SLinus Torvalds struct openflags boot_openflags; 1531da177e4SLinus Torvalds struct openflags openflags; 15484e945e3SPaolo 'Blaisorblade' Giarrusso unsigned shared:1; 15584e945e3SPaolo 'Blaisorblade' Giarrusso unsigned no_cow:1; 1561da177e4SLinus Torvalds struct cow cow; 1571da177e4SLinus Torvalds struct platform_device pdev; 15862f96cb0SJeff Dike struct request_queue *queue; 1594e6da0feSRichard Weinberger struct blk_mq_tag_set tag_set; 16062f96cb0SJeff Dike spinlock_t lock; 1614e6da0feSRichard Weinberger }; 1624e6da0feSRichard Weinberger 1634e6da0feSRichard Weinberger struct ubd_pdu { 164a0044bdfSJeff Dike struct scatterlist sg[MAX_SG]; 165a0044bdfSJeff Dike int start_sg, end_sg; 16647526903STejun Heo sector_t rq_pos; 1671da177e4SLinus Torvalds }; 1681da177e4SLinus Torvalds 1691da177e4SLinus Torvalds #define DEFAULT_COW { \ 1701da177e4SLinus Torvalds .file = NULL, \ 1711da177e4SLinus Torvalds .fd = -1, \ 1721da177e4SLinus Torvalds .bitmap = NULL, \ 1731da177e4SLinus Torvalds .bitmap_offset = 0, \ 1741da177e4SLinus Torvalds .data_offset = 0, \ 1751da177e4SLinus Torvalds } 1761da177e4SLinus Torvalds 1771da177e4SLinus Torvalds #define DEFAULT_UBD { \ 1781da177e4SLinus Torvalds .file = NULL, \ 1791da177e4SLinus Torvalds .count = 0, \ 1801da177e4SLinus Torvalds .fd = -1, \ 1811da177e4SLinus Torvalds .size = -1, \ 1821da177e4SLinus Torvalds .boot_openflags = OPEN_FLAGS, \ 1831da177e4SLinus Torvalds .openflags = OPEN_FLAGS, \ 1841da177e4SLinus Torvalds .no_cow = 0, \ 1856c29256cSJeff Dike .shared = 0, \ 1861da177e4SLinus Torvalds .cow = DEFAULT_COW, \ 18722e65004SThomas Gleixner .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \ 1881da177e4SLinus Torvalds } 1891da177e4SLinus Torvalds 190b8831a1dSJeff Dike /* Protected by ubd_lock */ 1915dc62b1bSWANG Cong static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; 1921da177e4SLinus Torvalds 1931da177e4SLinus Torvalds /* Only changed by fake_ide_setup which is a setup */ 1941da177e4SLinus Torvalds static int fake_ide = 0; 1951da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide_root = NULL; 1961da177e4SLinus Torvalds static struct proc_dir_entry *proc_ide = NULL; 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 static int ubd_init_request(struct blk_mq_tag_set *set, 2014e6da0feSRichard Weinberger struct request *req, unsigned int hctx_idx, 2024e6da0feSRichard Weinberger unsigned int numa_node); 2034e6da0feSRichard Weinberger 2041da177e4SLinus Torvalds static void make_proc_ide(void) 2051da177e4SLinus Torvalds { 2061da177e4SLinus Torvalds proc_ide_root = proc_mkdir("ide", NULL); 2071da177e4SLinus Torvalds proc_ide = proc_mkdir("ide0", proc_ide_root); 2081da177e4SLinus Torvalds } 2091da177e4SLinus Torvalds 2106613c5e8SAlexey Dobriyan static int fake_ide_media_proc_show(struct seq_file *m, void *v) 2111da177e4SLinus Torvalds { 2126613c5e8SAlexey Dobriyan seq_puts(m, "disk\n"); 2136613c5e8SAlexey Dobriyan return 0; 2146613c5e8SAlexey Dobriyan } 2151da177e4SLinus Torvalds 216c0a9290eSWANG Cong static void make_ide_entries(const char *dev_name) 2171da177e4SLinus Torvalds { 2181da177e4SLinus Torvalds struct proc_dir_entry *dir, *ent; 2191da177e4SLinus Torvalds char name[64]; 2201da177e4SLinus Torvalds 2211da177e4SLinus Torvalds if(proc_ide_root == NULL) make_proc_ide(); 2221da177e4SLinus Torvalds 2231da177e4SLinus Torvalds dir = proc_mkdir(dev_name, proc_ide); 2241da177e4SLinus Torvalds if(!dir) return; 2251da177e4SLinus Torvalds 2263f3942acSChristoph Hellwig ent = proc_create_single("media", S_IRUGO, dir, 2273f3942acSChristoph Hellwig fake_ide_media_proc_show); 2281da177e4SLinus Torvalds if(!ent) return; 229c0a9290eSWANG Cong snprintf(name, sizeof(name), "ide0/%s", dev_name); 2301da177e4SLinus Torvalds proc_symlink(dev_name, proc_ide_root, name); 2311da177e4SLinus Torvalds } 2321da177e4SLinus Torvalds 2331da177e4SLinus Torvalds static int fake_ide_setup(char *str) 2341da177e4SLinus Torvalds { 2351da177e4SLinus Torvalds fake_ide = 1; 236dc764e50SJeff Dike return 1; 2371da177e4SLinus Torvalds } 2381da177e4SLinus Torvalds 2391da177e4SLinus Torvalds __setup("fake_ide", fake_ide_setup); 2401da177e4SLinus Torvalds 2411da177e4SLinus Torvalds __uml_help(fake_ide_setup, 2421da177e4SLinus Torvalds "fake_ide\n" 2431da177e4SLinus Torvalds " Create ide0 entries that map onto ubd devices.\n\n" 2441da177e4SLinus Torvalds ); 2451da177e4SLinus Torvalds 2461da177e4SLinus Torvalds static int parse_unit(char **ptr) 2471da177e4SLinus Torvalds { 2481da177e4SLinus Torvalds char *str = *ptr, *end; 2491da177e4SLinus Torvalds int n = -1; 2501da177e4SLinus Torvalds 2511da177e4SLinus Torvalds if(isdigit(*str)) { 2521da177e4SLinus Torvalds n = simple_strtoul(str, &end, 0); 2531da177e4SLinus Torvalds if(end == str) 254dc764e50SJeff Dike return -1; 2551da177e4SLinus Torvalds *ptr = end; 2561da177e4SLinus Torvalds } 25797d88ac8SPaolo 'Blaisorblade' Giarrusso else if (('a' <= *str) && (*str <= 'z')) { 2581da177e4SLinus Torvalds n = *str - 'a'; 2591da177e4SLinus Torvalds str++; 2601da177e4SLinus Torvalds *ptr = str; 2611da177e4SLinus Torvalds } 262dc764e50SJeff Dike return n; 2631da177e4SLinus Torvalds } 2641da177e4SLinus Torvalds 265d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* If *index_out == -1 at exit, the passed option was a general one; 266d8d7c28eSPaolo 'Blaisorblade' Giarrusso * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it 267d8d7c28eSPaolo 'Blaisorblade' Giarrusso * should not be freed on exit. 268d8d7c28eSPaolo 'Blaisorblade' Giarrusso */ 269f28169d2SJeff Dike static int ubd_setup_common(char *str, int *index_out, char **error_out) 2701da177e4SLinus Torvalds { 2717d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 2721da177e4SLinus Torvalds struct openflags flags = global_openflags; 2731da177e4SLinus Torvalds char *backing_file; 274b8831a1dSJeff Dike int n, err = 0, i; 2751da177e4SLinus Torvalds 2761da177e4SLinus Torvalds if(index_out) *index_out = -1; 2771da177e4SLinus Torvalds n = *str; 2781da177e4SLinus Torvalds if(n == '='){ 2791da177e4SLinus Torvalds char *end; 2801da177e4SLinus Torvalds int major; 2811da177e4SLinus Torvalds 2821da177e4SLinus Torvalds str++; 2831da177e4SLinus Torvalds if(!strcmp(str, "sync")){ 2841da177e4SLinus Torvalds global_openflags = of_sync(global_openflags); 285b8831a1dSJeff Dike goto out1; 2861da177e4SLinus Torvalds } 2871da177e4SLinus Torvalds 288f28169d2SJeff Dike err = -EINVAL; 289b8831a1dSJeff Dike major = simple_strtoul(str, &end, 0); 290b8831a1dSJeff Dike if((*end != '\0') || (end == str)){ 291b8831a1dSJeff Dike *error_out = "Didn't parse major number"; 292b8831a1dSJeff Dike goto out1; 293b8831a1dSJeff Dike } 294b8831a1dSJeff Dike 295d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 296792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 297f28169d2SJeff Dike *error_out = "Can't assign a fake major twice"; 2981da177e4SLinus Torvalds goto out1; 2991da177e4SLinus Torvalds } 3001da177e4SLinus Torvalds 3011da177e4SLinus Torvalds fake_major = major; 3021da177e4SLinus Torvalds 3031da177e4SLinus Torvalds printk(KERN_INFO "Setting extra ubd major number to %d\n", 3041da177e4SLinus Torvalds major); 3051da177e4SLinus Torvalds err = 0; 3061da177e4SLinus Torvalds out1: 307d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 308f28169d2SJeff Dike return err; 3091da177e4SLinus Torvalds } 3101da177e4SLinus Torvalds 3111da177e4SLinus Torvalds n = parse_unit(&str); 3121da177e4SLinus Torvalds if(n < 0){ 313f28169d2SJeff Dike *error_out = "Couldn't parse device number"; 314f28169d2SJeff Dike return -EINVAL; 3151da177e4SLinus Torvalds } 3161da177e4SLinus Torvalds if(n >= MAX_DEV){ 317f28169d2SJeff Dike *error_out = "Device number out of range"; 318f28169d2SJeff Dike return 1; 3191da177e4SLinus Torvalds } 3201da177e4SLinus Torvalds 321f28169d2SJeff Dike err = -EBUSY; 322d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 3231da177e4SLinus Torvalds 3247d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 3257d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file != NULL){ 326f28169d2SJeff Dike *error_out = "Device is already configured"; 3271da177e4SLinus Torvalds goto out; 3281da177e4SLinus Torvalds } 3291da177e4SLinus Torvalds 3301da177e4SLinus Torvalds if (index_out) 3311da177e4SLinus Torvalds *index_out = n; 3321da177e4SLinus Torvalds 333f28169d2SJeff Dike err = -EINVAL; 3346c29256cSJeff Dike for (i = 0; i < sizeof("rscd="); i++) { 3351da177e4SLinus Torvalds switch (*str) { 3361da177e4SLinus Torvalds case 'r': 3371da177e4SLinus Torvalds flags.w = 0; 3381da177e4SLinus Torvalds break; 3391da177e4SLinus Torvalds case 's': 3401da177e4SLinus Torvalds flags.s = 1; 3411da177e4SLinus Torvalds break; 3421da177e4SLinus Torvalds case 'd': 3437d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->no_cow = 1; 3441da177e4SLinus Torvalds break; 3456c29256cSJeff Dike case 'c': 3467d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->shared = 1; 3476c29256cSJeff Dike break; 3481da177e4SLinus Torvalds case '=': 3491da177e4SLinus Torvalds str++; 3501da177e4SLinus Torvalds goto break_loop; 3511da177e4SLinus Torvalds default: 352f28169d2SJeff Dike *error_out = "Expected '=' or flag letter " 353f28169d2SJeff Dike "(r, s, c, or d)"; 3541da177e4SLinus Torvalds goto out; 3551da177e4SLinus Torvalds } 3561da177e4SLinus Torvalds str++; 3571da177e4SLinus Torvalds } 3581da177e4SLinus Torvalds 3591da177e4SLinus Torvalds if (*str == '=') 360f28169d2SJeff Dike *error_out = "Too many flags specified"; 3611da177e4SLinus Torvalds else 362f28169d2SJeff Dike *error_out = "Missing '='"; 3631da177e4SLinus Torvalds goto out; 3641da177e4SLinus Torvalds 3651da177e4SLinus Torvalds break_loop: 3661da177e4SLinus Torvalds backing_file = strchr(str, ','); 3671da177e4SLinus Torvalds 368f28169d2SJeff Dike if (backing_file == NULL) 3691da177e4SLinus Torvalds backing_file = strchr(str, ':'); 3701da177e4SLinus Torvalds 371f28169d2SJeff Dike if(backing_file != NULL){ 372f28169d2SJeff Dike if(ubd_dev->no_cow){ 373f28169d2SJeff Dike *error_out = "Can't specify both 'd' and a cow file"; 374f28169d2SJeff Dike goto out; 375f28169d2SJeff Dike } 3761da177e4SLinus Torvalds else { 3771da177e4SLinus Torvalds *backing_file = '\0'; 3781da177e4SLinus Torvalds backing_file++; 3791da177e4SLinus Torvalds } 3801da177e4SLinus Torvalds } 381f28169d2SJeff Dike err = 0; 3827d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->file = str; 3837d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.file = backing_file; 3847d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->boot_openflags = flags; 3851da177e4SLinus Torvalds out: 386d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 387f28169d2SJeff Dike return err; 3881da177e4SLinus Torvalds } 3891da177e4SLinus Torvalds 3901da177e4SLinus Torvalds static int ubd_setup(char *str) 3911da177e4SLinus Torvalds { 392f28169d2SJeff Dike char *error; 393f28169d2SJeff Dike int err; 394f28169d2SJeff Dike 395f28169d2SJeff Dike err = ubd_setup_common(str, NULL, &error); 396f28169d2SJeff Dike if(err) 397f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize device with \"%s\" : " 398f28169d2SJeff Dike "%s\n", str, error); 399f28169d2SJeff Dike return 1; 4001da177e4SLinus Torvalds } 4011da177e4SLinus Torvalds 4021da177e4SLinus Torvalds __setup("ubd", ubd_setup); 4031da177e4SLinus Torvalds __uml_help(ubd_setup, 4041da177e4SLinus Torvalds "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" 4051da177e4SLinus Torvalds " This is used to associate a device with a file in the underlying\n" 4061da177e4SLinus Torvalds " filesystem. When specifying two filenames, the first one is the\n" 4071da177e4SLinus Torvalds " COW name and the second is the backing file name. As separator you can\n" 4081da177e4SLinus Torvalds " use either a ':' or a ',': the first one allows writing things like;\n" 4091da177e4SLinus Torvalds " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" 4101da177e4SLinus Torvalds " while with a ',' the shell would not expand the 2nd '~'.\n" 411f28169d2SJeff Dike " When using only one filename, UML will detect whether to treat it like\n" 4121da177e4SLinus Torvalds " a COW file or a backing file. To override this detection, add the 'd'\n" 4131da177e4SLinus Torvalds " flag:\n" 4141da177e4SLinus Torvalds " ubd0d=BackingFile\n" 4151da177e4SLinus Torvalds " Usually, there is a filesystem in the file, but \n" 4161da177e4SLinus Torvalds " that's not required. Swap devices containing swap files can be\n" 4171da177e4SLinus Torvalds " specified like this. Also, a file which doesn't contain a\n" 4181da177e4SLinus Torvalds " filesystem can have its contents read in the virtual \n" 4191da177e4SLinus Torvalds " machine by running 'dd' on the device. <n> must be in the range\n" 4201da177e4SLinus Torvalds " 0 to 7. Appending an 'r' to the number will cause that device\n" 4211da177e4SLinus Torvalds " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" 42220ede453SJeff Dike " an 's' will cause data to be written to disk on the host immediately.\n" 42320ede453SJeff Dike " 'c' will cause the device to be treated as being shared between multiple\n" 42420ede453SJeff Dike " UMLs and file locking will be turned off - this is appropriate for a\n" 42520ede453SJeff Dike " cluster filesystem and inappropriate at almost all other times.\n\n" 4261da177e4SLinus Torvalds ); 4271da177e4SLinus Torvalds 4288299ca5cSJeff Dike static int udb_setup(char *str) 4291da177e4SLinus Torvalds { 4301da177e4SLinus Torvalds printk("udb%s specified on command line is almost certainly a ubd -> " 4311da177e4SLinus Torvalds "udb TYPO\n", str); 432dc764e50SJeff Dike return 1; 4331da177e4SLinus Torvalds } 4341da177e4SLinus Torvalds 4351da177e4SLinus Torvalds __setup("udb", udb_setup); 4361da177e4SLinus Torvalds __uml_help(udb_setup, 4371da177e4SLinus Torvalds "udb\n" 4380894e27eSJeff Dike " This option is here solely to catch ubd -> udb typos, which can be\n" 4390894e27eSJeff Dike " to impossible to catch visually unless you specifically look for\n" 4400894e27eSJeff Dike " them. The only result of any option starting with 'udb' is an error\n" 4411da177e4SLinus Torvalds " in the boot output.\n\n" 4421da177e4SLinus Torvalds ); 4431da177e4SLinus Torvalds 44491acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 4455dc62b1bSWANG Cong static int thread_fd = -1; 44609ace81cSJeff Dike 447f88f0bdfSAnton Ivanov /* Function to read several request pointers at a time 448f88f0bdfSAnton Ivanov * handling fractional reads if (and as) needed 449f88f0bdfSAnton Ivanov */ 450f88f0bdfSAnton Ivanov 451f88f0bdfSAnton Ivanov static int bulk_req_safe_read( 452f88f0bdfSAnton Ivanov int fd, 453f88f0bdfSAnton Ivanov struct io_thread_req * (*request_buffer)[], 454f88f0bdfSAnton Ivanov struct io_thread_req **remainder, 455f88f0bdfSAnton Ivanov int *remainder_size, 456f88f0bdfSAnton Ivanov int max_recs 457f88f0bdfSAnton Ivanov ) 458f88f0bdfSAnton Ivanov { 459f88f0bdfSAnton Ivanov int n = 0; 460f88f0bdfSAnton Ivanov int res = 0; 461f88f0bdfSAnton Ivanov 462f88f0bdfSAnton Ivanov if (*remainder_size > 0) { 463f88f0bdfSAnton Ivanov memmove( 464f88f0bdfSAnton Ivanov (char *) request_buffer, 465f88f0bdfSAnton Ivanov (char *) remainder, *remainder_size 466f88f0bdfSAnton Ivanov ); 467f88f0bdfSAnton Ivanov n = *remainder_size; 468f88f0bdfSAnton Ivanov } 469f88f0bdfSAnton Ivanov 470f88f0bdfSAnton Ivanov res = os_read_file( 471f88f0bdfSAnton Ivanov fd, 472f88f0bdfSAnton Ivanov ((char *) request_buffer) + *remainder_size, 473f88f0bdfSAnton Ivanov sizeof(struct io_thread_req *)*max_recs 474f88f0bdfSAnton Ivanov - *remainder_size 475f88f0bdfSAnton Ivanov ); 476f88f0bdfSAnton Ivanov if (res > 0) { 477f88f0bdfSAnton Ivanov n += res; 478f88f0bdfSAnton Ivanov if ((n % sizeof(struct io_thread_req *)) > 0) { 479f88f0bdfSAnton Ivanov /* 480f88f0bdfSAnton Ivanov * Read somehow returned not a multiple of dword 481f88f0bdfSAnton Ivanov * theoretically possible, but never observed in the 482f88f0bdfSAnton Ivanov * wild, so read routine must be able to handle it 483f88f0bdfSAnton Ivanov */ 484f88f0bdfSAnton Ivanov *remainder_size = n % sizeof(struct io_thread_req *); 485f88f0bdfSAnton Ivanov WARN(*remainder_size > 0, "UBD IPC read returned a partial result"); 486f88f0bdfSAnton Ivanov memmove( 487f88f0bdfSAnton Ivanov remainder, 488f88f0bdfSAnton Ivanov ((char *) request_buffer) + 489f88f0bdfSAnton Ivanov (n/sizeof(struct io_thread_req *))*sizeof(struct io_thread_req *), 490f88f0bdfSAnton Ivanov *remainder_size 491f88f0bdfSAnton Ivanov ); 492f88f0bdfSAnton Ivanov n = n - *remainder_size; 493f88f0bdfSAnton Ivanov } 494f88f0bdfSAnton Ivanov } else { 495f88f0bdfSAnton Ivanov n = res; 496f88f0bdfSAnton Ivanov } 497f88f0bdfSAnton Ivanov return n; 498f88f0bdfSAnton Ivanov } 499f88f0bdfSAnton Ivanov 50062f96cb0SJeff Dike /* Called without dev->lock held, and only in interrupt context. */ 50191acb21fSJeff Dike static void ubd_handler(void) 50291acb21fSJeff Dike { 50391acb21fSJeff Dike int n; 504f88f0bdfSAnton Ivanov int count; 50509ace81cSJeff Dike 506a0044bdfSJeff Dike while(1){ 507f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 508f88f0bdfSAnton Ivanov thread_fd, 509f88f0bdfSAnton Ivanov irq_req_buffer, 510f88f0bdfSAnton Ivanov &irq_remainder, 511f88f0bdfSAnton Ivanov &irq_remainder_size, 512f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 513f88f0bdfSAnton Ivanov ); 514f88f0bdfSAnton Ivanov if (n < 0) { 515a0044bdfSJeff Dike if(n == -EAGAIN) 516a0044bdfSJeff Dike break; 517a0044bdfSJeff Dike printk(KERN_ERR "spurious interrupt in ubd_handler, " 518a0044bdfSJeff Dike "err = %d\n", -n); 51991acb21fSJeff Dike return; 52091acb21fSJeff Dike } 521f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 5224e6da0feSRichard Weinberger struct io_thread_req *io_req = (*irq_req_buffer)[count]; 5234e6da0feSRichard Weinberger int err = io_req->error ? BLK_STS_IOERR : BLK_STS_OK; 524a0044bdfSJeff Dike 5254e6da0feSRichard Weinberger if (!blk_update_request(io_req->req, err, io_req->length)) 5264e6da0feSRichard Weinberger __blk_mq_end_request(io_req->req, err); 5274e6da0feSRichard Weinberger 5284e6da0feSRichard Weinberger kfree(io_req); 529a0044bdfSJeff Dike } 53091acb21fSJeff Dike } 53109ace81cSJeff Dike 5324e6da0feSRichard Weinberger reactivate_fd(thread_fd, UBD_IRQ); 5334e6da0feSRichard Weinberger } 5344e6da0feSRichard Weinberger 5357bea96fdSAl Viro static irqreturn_t ubd_intr(int irq, void *dev) 5361da177e4SLinus Torvalds { 53791acb21fSJeff Dike ubd_handler(); 538dc764e50SJeff Dike return IRQ_HANDLED; 5391da177e4SLinus Torvalds } 5401da177e4SLinus Torvalds 54191acb21fSJeff Dike /* Only changed by ubd_init, which is an initcall. */ 54291acb21fSJeff Dike static int io_pid = -1; 54391acb21fSJeff Dike 5445dc62b1bSWANG Cong static void kill_io_thread(void) 54591acb21fSJeff Dike { 54691acb21fSJeff Dike if(io_pid != -1) 54791acb21fSJeff Dike os_kill_process(io_pid, 1); 54891acb21fSJeff Dike } 54991acb21fSJeff Dike 55091acb21fSJeff Dike __uml_exitcall(kill_io_thread); 55191acb21fSJeff Dike 552d8d7c28eSPaolo 'Blaisorblade' Giarrusso static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) 5531da177e4SLinus Torvalds { 5541da177e4SLinus Torvalds char *file; 55585356398SRichard Weinberger int fd; 55685356398SRichard Weinberger int err; 5571da177e4SLinus Torvalds 55885356398SRichard Weinberger __u32 version; 55985356398SRichard Weinberger __u32 align; 56085356398SRichard Weinberger char *backing_file; 56185356398SRichard Weinberger time_t mtime; 56285356398SRichard Weinberger unsigned long long size; 56385356398SRichard Weinberger int sector_size; 56485356398SRichard Weinberger int bitmap_offset; 56585356398SRichard Weinberger 56685356398SRichard Weinberger if (ubd_dev->file && ubd_dev->cow.file) { 56785356398SRichard Weinberger file = ubd_dev->cow.file; 56885356398SRichard Weinberger 56985356398SRichard Weinberger goto out; 57085356398SRichard Weinberger } 57185356398SRichard Weinberger 572d4afcba9SMartin Pärtel fd = os_open_file(ubd_dev->file, of_read(OPENFLAGS()), 0); 57385356398SRichard Weinberger if (fd < 0) 57485356398SRichard Weinberger return fd; 57585356398SRichard Weinberger 57685356398SRichard Weinberger err = read_cow_header(file_reader, &fd, &version, &backing_file, \ 57785356398SRichard Weinberger &mtime, &size, §or_size, &align, &bitmap_offset); 57885356398SRichard Weinberger os_close_file(fd); 57985356398SRichard Weinberger 58085356398SRichard Weinberger if(err == -EINVAL) 58185356398SRichard Weinberger file = ubd_dev->file; 58285356398SRichard Weinberger else 58385356398SRichard Weinberger file = backing_file; 58485356398SRichard Weinberger 58585356398SRichard Weinberger out: 586dc764e50SJeff Dike return os_file_size(file, size_out); 5871da177e4SLinus Torvalds } 5881da177e4SLinus Torvalds 5895dc62b1bSWANG Cong static int read_cow_bitmap(int fd, void *buf, int offset, int len) 5905dc62b1bSWANG Cong { 5915dc62b1bSWANG Cong int err; 5925dc62b1bSWANG Cong 5938c6157b6SAnton Ivanov err = os_pread_file(fd, buf, len, offset); 5945dc62b1bSWANG Cong if (err < 0) 5955dc62b1bSWANG Cong return err; 5965dc62b1bSWANG Cong 5975dc62b1bSWANG Cong return 0; 5985dc62b1bSWANG Cong } 5995dc62b1bSWANG Cong 6005dc62b1bSWANG Cong static int backing_file_mismatch(char *file, __u64 size, time_t mtime) 6015dc62b1bSWANG Cong { 6025dc62b1bSWANG Cong unsigned long modtime; 6035dc62b1bSWANG Cong unsigned long long actual; 6045dc62b1bSWANG Cong int err; 6055dc62b1bSWANG Cong 6065dc62b1bSWANG Cong err = os_file_modtime(file, &modtime); 6075dc62b1bSWANG Cong if (err < 0) { 6085dc62b1bSWANG Cong printk(KERN_ERR "Failed to get modification time of backing " 6095dc62b1bSWANG Cong "file \"%s\", err = %d\n", file, -err); 6105dc62b1bSWANG Cong return err; 6115dc62b1bSWANG Cong } 6125dc62b1bSWANG Cong 6135dc62b1bSWANG Cong err = os_file_size(file, &actual); 6145dc62b1bSWANG Cong if (err < 0) { 6155dc62b1bSWANG Cong printk(KERN_ERR "Failed to get size of backing file \"%s\", " 6165dc62b1bSWANG Cong "err = %d\n", file, -err); 6175dc62b1bSWANG Cong return err; 6185dc62b1bSWANG Cong } 6195dc62b1bSWANG Cong 6205dc62b1bSWANG Cong if (actual != size) { 6215dc62b1bSWANG Cong /*__u64 can be a long on AMD64 and with %lu GCC complains; so 6225dc62b1bSWANG Cong * the typecast.*/ 6235dc62b1bSWANG Cong printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " 6245dc62b1bSWANG Cong "vs backing file\n", (unsigned long long) size, actual); 6255dc62b1bSWANG Cong return -EINVAL; 6265dc62b1bSWANG Cong } 6275dc62b1bSWANG Cong if (modtime != mtime) { 6285dc62b1bSWANG Cong printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " 6295dc62b1bSWANG Cong "backing file\n", mtime, modtime); 6305dc62b1bSWANG Cong return -EINVAL; 6315dc62b1bSWANG Cong } 6325dc62b1bSWANG Cong return 0; 6335dc62b1bSWANG Cong } 6345dc62b1bSWANG Cong 6355dc62b1bSWANG Cong static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) 6365dc62b1bSWANG Cong { 6375dc62b1bSWANG Cong struct uml_stat buf1, buf2; 6385dc62b1bSWANG Cong int err; 6395dc62b1bSWANG Cong 6405dc62b1bSWANG Cong if (from_cmdline == NULL) 6415dc62b1bSWANG Cong return 0; 6425dc62b1bSWANG Cong if (!strcmp(from_cmdline, from_cow)) 6435dc62b1bSWANG Cong return 0; 6445dc62b1bSWANG Cong 6455dc62b1bSWANG Cong err = os_stat_file(from_cmdline, &buf1); 6465dc62b1bSWANG Cong if (err < 0) { 6475dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, 6485dc62b1bSWANG Cong -err); 6495dc62b1bSWANG Cong return 0; 6505dc62b1bSWANG Cong } 6515dc62b1bSWANG Cong err = os_stat_file(from_cow, &buf2); 6525dc62b1bSWANG Cong if (err < 0) { 6535dc62b1bSWANG Cong printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, 6545dc62b1bSWANG Cong -err); 6555dc62b1bSWANG Cong return 1; 6565dc62b1bSWANG Cong } 6575dc62b1bSWANG Cong if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) 6585dc62b1bSWANG Cong return 0; 6595dc62b1bSWANG Cong 6605dc62b1bSWANG Cong printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " 6615dc62b1bSWANG Cong "\"%s\" specified in COW header of \"%s\"\n", 6625dc62b1bSWANG Cong from_cmdline, from_cow, cow); 6635dc62b1bSWANG Cong return 1; 6645dc62b1bSWANG Cong } 6655dc62b1bSWANG Cong 6665dc62b1bSWANG Cong static int open_ubd_file(char *file, struct openflags *openflags, int shared, 6675dc62b1bSWANG Cong char **backing_file_out, int *bitmap_offset_out, 6685dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out, 6695dc62b1bSWANG Cong int *create_cow_out) 6705dc62b1bSWANG Cong { 6715dc62b1bSWANG Cong time_t mtime; 6725dc62b1bSWANG Cong unsigned long long size; 6735dc62b1bSWANG Cong __u32 version, align; 6745dc62b1bSWANG Cong char *backing_file; 6755dc62b1bSWANG Cong int fd, err, sectorsize, asked_switch, mode = 0644; 6765dc62b1bSWANG Cong 6775dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6785dc62b1bSWANG Cong if (fd < 0) { 6795dc62b1bSWANG Cong if ((fd == -ENOENT) && (create_cow_out != NULL)) 6805dc62b1bSWANG Cong *create_cow_out = 1; 6815dc62b1bSWANG Cong if (!openflags->w || 6825dc62b1bSWANG Cong ((fd != -EROFS) && (fd != -EACCES))) 6835dc62b1bSWANG Cong return fd; 6845dc62b1bSWANG Cong openflags->w = 0; 6855dc62b1bSWANG Cong fd = os_open_file(file, *openflags, mode); 6865dc62b1bSWANG Cong if (fd < 0) 6875dc62b1bSWANG Cong return fd; 6885dc62b1bSWANG Cong } 6895dc62b1bSWANG Cong 6905dc62b1bSWANG Cong if (shared) 6915dc62b1bSWANG Cong printk(KERN_INFO "Not locking \"%s\" on the host\n", file); 6925dc62b1bSWANG Cong else { 6935dc62b1bSWANG Cong err = os_lock_file(fd, openflags->w); 6945dc62b1bSWANG Cong if (err < 0) { 6955dc62b1bSWANG Cong printk(KERN_ERR "Failed to lock '%s', err = %d\n", 6965dc62b1bSWANG Cong file, -err); 6975dc62b1bSWANG Cong goto out_close; 6985dc62b1bSWANG Cong } 6995dc62b1bSWANG Cong } 7005dc62b1bSWANG Cong 7015dc62b1bSWANG Cong /* Successful return case! */ 7025dc62b1bSWANG Cong if (backing_file_out == NULL) 7035dc62b1bSWANG Cong return fd; 7045dc62b1bSWANG Cong 7055dc62b1bSWANG Cong err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, 7065dc62b1bSWANG Cong &size, §orsize, &align, bitmap_offset_out); 7075dc62b1bSWANG Cong if (err && (*backing_file_out != NULL)) { 7085dc62b1bSWANG Cong printk(KERN_ERR "Failed to read COW header from COW file " 7095dc62b1bSWANG Cong "\"%s\", errno = %d\n", file, -err); 7105dc62b1bSWANG Cong goto out_close; 7115dc62b1bSWANG Cong } 7125dc62b1bSWANG Cong if (err) 7135dc62b1bSWANG Cong return fd; 7145dc62b1bSWANG Cong 7155dc62b1bSWANG Cong asked_switch = path_requires_switch(*backing_file_out, backing_file, 7165dc62b1bSWANG Cong file); 7175dc62b1bSWANG Cong 7185dc62b1bSWANG Cong /* Allow switching only if no mismatch. */ 7195dc62b1bSWANG Cong if (asked_switch && !backing_file_mismatch(*backing_file_out, size, 7205dc62b1bSWANG Cong mtime)) { 7215dc62b1bSWANG Cong printk(KERN_ERR "Switching backing file to '%s'\n", 7225dc62b1bSWANG Cong *backing_file_out); 7235dc62b1bSWANG Cong err = write_cow_header(file, fd, *backing_file_out, 7245dc62b1bSWANG Cong sectorsize, align, &size); 7255dc62b1bSWANG Cong if (err) { 7265dc62b1bSWANG Cong printk(KERN_ERR "Switch failed, errno = %d\n", -err); 7275dc62b1bSWANG Cong goto out_close; 7285dc62b1bSWANG Cong } 7295dc62b1bSWANG Cong } else { 7305dc62b1bSWANG Cong *backing_file_out = backing_file; 7315dc62b1bSWANG Cong err = backing_file_mismatch(*backing_file_out, size, mtime); 7325dc62b1bSWANG Cong if (err) 7335dc62b1bSWANG Cong goto out_close; 7345dc62b1bSWANG Cong } 7355dc62b1bSWANG Cong 7365dc62b1bSWANG Cong cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, 7375dc62b1bSWANG Cong bitmap_len_out, data_offset_out); 7385dc62b1bSWANG Cong 7395dc62b1bSWANG Cong return fd; 7405dc62b1bSWANG Cong out_close: 7415dc62b1bSWANG Cong os_close_file(fd); 7425dc62b1bSWANG Cong return err; 7435dc62b1bSWANG Cong } 7445dc62b1bSWANG Cong 7455dc62b1bSWANG Cong static int create_cow_file(char *cow_file, char *backing_file, 7465dc62b1bSWANG Cong struct openflags flags, 7475dc62b1bSWANG Cong int sectorsize, int alignment, int *bitmap_offset_out, 7485dc62b1bSWANG Cong unsigned long *bitmap_len_out, int *data_offset_out) 7495dc62b1bSWANG Cong { 7505dc62b1bSWANG Cong int err, fd; 7515dc62b1bSWANG Cong 7525dc62b1bSWANG Cong flags.c = 1; 7535dc62b1bSWANG Cong fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); 7545dc62b1bSWANG Cong if (fd < 0) { 7555dc62b1bSWANG Cong err = fd; 7565dc62b1bSWANG Cong printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", 7575dc62b1bSWANG Cong cow_file, -err); 7585dc62b1bSWANG Cong goto out; 7595dc62b1bSWANG Cong } 7605dc62b1bSWANG Cong 7615dc62b1bSWANG Cong err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, 7625dc62b1bSWANG Cong bitmap_offset_out, bitmap_len_out, 7635dc62b1bSWANG Cong data_offset_out); 7645dc62b1bSWANG Cong if (!err) 7655dc62b1bSWANG Cong return fd; 7665dc62b1bSWANG Cong os_close_file(fd); 7675dc62b1bSWANG Cong out: 7685dc62b1bSWANG Cong return err; 7695dc62b1bSWANG Cong } 7705dc62b1bSWANG Cong 7715f75a4f8SPaolo 'Blaisorblade' Giarrusso static void ubd_close_dev(struct ubd *ubd_dev) 7721da177e4SLinus Torvalds { 7737d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 7747d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file == NULL) 7751da177e4SLinus Torvalds return; 7761da177e4SLinus Torvalds 7777d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->cow.fd); 7787d314e34SPaolo 'Blaisorblade' Giarrusso vfree(ubd_dev->cow.bitmap); 7797d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap = NULL; 7801da177e4SLinus Torvalds } 7811da177e4SLinus Torvalds 7827d314e34SPaolo 'Blaisorblade' Giarrusso static int ubd_open_dev(struct ubd *ubd_dev) 7831da177e4SLinus Torvalds { 7841da177e4SLinus Torvalds struct openflags flags; 7851da177e4SLinus Torvalds char **back_ptr; 7861da177e4SLinus Torvalds int err, create_cow, *create_ptr; 7870bf16bffSPaolo 'Blaisorblade' Giarrusso int fd; 7881da177e4SLinus Torvalds 7897d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags = ubd_dev->boot_openflags; 7901da177e4SLinus Torvalds create_cow = 0; 7917d314e34SPaolo 'Blaisorblade' Giarrusso create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; 7927d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; 7930bf16bffSPaolo 'Blaisorblade' Giarrusso 7940bf16bffSPaolo 'Blaisorblade' Giarrusso fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, 7957d314e34SPaolo 'Blaisorblade' Giarrusso back_ptr, &ubd_dev->cow.bitmap_offset, 7967d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, 7976c29256cSJeff Dike create_ptr); 7981da177e4SLinus Torvalds 7990bf16bffSPaolo 'Blaisorblade' Giarrusso if((fd == -ENOENT) && create_cow){ 8000bf16bffSPaolo 'Blaisorblade' Giarrusso fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, 8017d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->openflags, 1 << 9, PAGE_SIZE, 8027d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_offset, 8037d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.bitmap_len, 8047d314e34SPaolo 'Blaisorblade' Giarrusso &ubd_dev->cow.data_offset); 8050bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd >= 0){ 8061da177e4SLinus Torvalds printk(KERN_INFO "Creating \"%s\" as COW file for " 8077d314e34SPaolo 'Blaisorblade' Giarrusso "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); 8081da177e4SLinus Torvalds } 8091da177e4SLinus Torvalds } 8101da177e4SLinus Torvalds 8110bf16bffSPaolo 'Blaisorblade' Giarrusso if(fd < 0){ 8127d314e34SPaolo 'Blaisorblade' Giarrusso printk("Failed to open '%s', errno = %d\n", ubd_dev->file, 8130bf16bffSPaolo 'Blaisorblade' Giarrusso -fd); 8140bf16bffSPaolo 'Blaisorblade' Giarrusso return fd; 8151da177e4SLinus Torvalds } 8160bf16bffSPaolo 'Blaisorblade' Giarrusso ubd_dev->fd = fd; 8171da177e4SLinus Torvalds 8187d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 819086fa5ffSMartin K. Petersen blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); 820f4768ffdSJeff Dike 8211da177e4SLinus Torvalds err = -ENOMEM; 822da2486baSJesper Juhl ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); 8237d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.bitmap == NULL){ 8241da177e4SLinus Torvalds printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); 8251da177e4SLinus Torvalds goto error; 8261da177e4SLinus Torvalds } 8271da177e4SLinus Torvalds flush_tlb_kernel_vm(); 8281da177e4SLinus Torvalds 8297d314e34SPaolo 'Blaisorblade' Giarrusso err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, 8307d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_offset, 8317d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.bitmap_len); 8321da177e4SLinus Torvalds if(err < 0) 8331da177e4SLinus Torvalds goto error; 8341da177e4SLinus Torvalds 8357d314e34SPaolo 'Blaisorblade' Giarrusso flags = ubd_dev->openflags; 8361da177e4SLinus Torvalds flags.w = 0; 8377d314e34SPaolo 'Blaisorblade' Giarrusso err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, 8386c29256cSJeff Dike NULL, NULL, NULL, NULL); 8391da177e4SLinus Torvalds if(err < 0) goto error; 8407d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->cow.fd = err; 8411da177e4SLinus Torvalds } 842dc764e50SJeff Dike return 0; 8431da177e4SLinus Torvalds error: 8447d314e34SPaolo 'Blaisorblade' Giarrusso os_close_file(ubd_dev->fd); 845dc764e50SJeff Dike return err; 8461da177e4SLinus Torvalds } 8471da177e4SLinus Torvalds 8482e3f5251SJeff Dike static void ubd_device_release(struct device *dev) 8492e3f5251SJeff Dike { 8508691b97bSGreg Kroah-Hartman struct ubd *ubd_dev = dev_get_drvdata(dev); 8512e3f5251SJeff Dike 8522e3f5251SJeff Dike blk_cleanup_queue(ubd_dev->queue); 8534e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 8542e3f5251SJeff Dike *ubd_dev = ((struct ubd) DEFAULT_UBD); 8552e3f5251SJeff Dike } 8562e3f5251SJeff Dike 8575f75a4f8SPaolo 'Blaisorblade' Giarrusso static int ubd_disk_register(int major, u64 size, int unit, 8581da177e4SLinus Torvalds struct gendisk **disk_out) 8591da177e4SLinus Torvalds { 860d72a5783SDan Williams struct device *parent = NULL; 8611da177e4SLinus Torvalds struct gendisk *disk; 8621da177e4SLinus Torvalds 8631da177e4SLinus Torvalds disk = alloc_disk(1 << UBD_SHIFT); 8641da177e4SLinus Torvalds if(disk == NULL) 865dc764e50SJeff Dike return -ENOMEM; 8661da177e4SLinus Torvalds 8671da177e4SLinus Torvalds disk->major = major; 8681da177e4SLinus Torvalds disk->first_minor = unit << UBD_SHIFT; 8691da177e4SLinus Torvalds disk->fops = &ubd_blops; 8701da177e4SLinus Torvalds set_capacity(disk, size / 512); 871792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) 8721da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd%c", 'a' + unit); 873ce7b0f46SGreg Kroah-Hartman else 8741da177e4SLinus Torvalds sprintf(disk->disk_name, "ubd_fake%d", unit); 8751da177e4SLinus Torvalds 8761da177e4SLinus Torvalds /* sysfs register (not for ide fake devices) */ 877792dd4fcSChristoph Hellwig if (major == UBD_MAJOR) { 8787d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.id = unit; 8797d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[unit].pdev.name = DRIVER_NAME; 8802e3f5251SJeff Dike ubd_devs[unit].pdev.dev.release = ubd_device_release; 8818691b97bSGreg Kroah-Hartman dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); 8827d314e34SPaolo 'Blaisorblade' Giarrusso platform_device_register(&ubd_devs[unit].pdev); 883d72a5783SDan Williams parent = &ubd_devs[unit].pdev.dev; 8841da177e4SLinus Torvalds } 8851da177e4SLinus Torvalds 8867d314e34SPaolo 'Blaisorblade' Giarrusso disk->private_data = &ubd_devs[unit]; 88762f96cb0SJeff Dike disk->queue = ubd_devs[unit].queue; 888fef912bfSHannes Reinecke device_add_disk(parent, disk, NULL); 8891da177e4SLinus Torvalds 8901da177e4SLinus Torvalds *disk_out = disk; 8911da177e4SLinus Torvalds return 0; 8921da177e4SLinus Torvalds } 8931da177e4SLinus Torvalds 8941da177e4SLinus Torvalds #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) 8951da177e4SLinus Torvalds 8964e6da0feSRichard Weinberger static const struct blk_mq_ops ubd_mq_ops = { 8974e6da0feSRichard Weinberger .queue_rq = ubd_queue_rq, 8984e6da0feSRichard Weinberger .init_request = ubd_init_request, 8994e6da0feSRichard Weinberger }; 9004e6da0feSRichard Weinberger 901f28169d2SJeff Dike static int ubd_add(int n, char **error_out) 9021da177e4SLinus Torvalds { 9037d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[n]; 904f28169d2SJeff Dike int err = 0; 9051da177e4SLinus Torvalds 9067d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 907ec7cf783SJeff Dike goto out; 9081da177e4SLinus Torvalds 9097d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_file_size(ubd_dev, &ubd_dev->size); 910f28169d2SJeff Dike if(err < 0){ 911f28169d2SJeff Dike *error_out = "Couldn't determine size of device's file"; 91280c13749SJeff Dike goto out; 913f28169d2SJeff Dike } 9141da177e4SLinus Torvalds 9157d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->size = ROUND_BLOCK(ubd_dev->size); 9161da177e4SLinus Torvalds 9174e6da0feSRichard Weinberger ubd_dev->tag_set.ops = &ubd_mq_ops; 9184e6da0feSRichard Weinberger ubd_dev->tag_set.queue_depth = 64; 9194e6da0feSRichard Weinberger ubd_dev->tag_set.numa_node = NUMA_NO_NODE; 9204e6da0feSRichard Weinberger ubd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; 9214e6da0feSRichard Weinberger ubd_dev->tag_set.cmd_size = sizeof(struct ubd_pdu); 9224e6da0feSRichard Weinberger ubd_dev->tag_set.driver_data = ubd_dev; 9234e6da0feSRichard Weinberger ubd_dev->tag_set.nr_hw_queues = 1; 924a0044bdfSJeff Dike 9254e6da0feSRichard Weinberger err = blk_mq_alloc_tag_set(&ubd_dev->tag_set); 9264e6da0feSRichard Weinberger if (err) 92780c13749SJeff Dike goto out; 9284e6da0feSRichard Weinberger 9294e6da0feSRichard Weinberger ubd_dev->queue = blk_mq_init_queue(&ubd_dev->tag_set); 9304e6da0feSRichard Weinberger if (IS_ERR(ubd_dev->queue)) { 9314e6da0feSRichard Weinberger err = PTR_ERR(ubd_dev->queue); 9324e6da0feSRichard Weinberger goto out_cleanup; 93362f96cb0SJeff Dike } 9344e6da0feSRichard Weinberger 93562f96cb0SJeff Dike ubd_dev->queue->queuedata = ubd_dev; 936f935a8ceSJens Axboe blk_queue_write_cache(ubd_dev->queue, true, false); 93762f96cb0SJeff Dike 9388a78362cSMartin K. Petersen blk_queue_max_segments(ubd_dev->queue, MAX_SG); 939792dd4fcSChristoph Hellwig err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); 94062f96cb0SJeff Dike if(err){ 94162f96cb0SJeff Dike *error_out = "Failed to register device"; 9424e6da0feSRichard Weinberger goto out_cleanup_tags; 94362f96cb0SJeff Dike } 9441da177e4SLinus Torvalds 945792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) 9465f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_disk_register(fake_major, ubd_dev->size, n, 9471da177e4SLinus Torvalds &fake_gendisk[n]); 9481da177e4SLinus Torvalds 94983380cc1SJeff Dike /* 95083380cc1SJeff Dike * Perhaps this should also be under the "if (fake_major)" above 95183380cc1SJeff Dike * using the fake_disk->disk_name 95283380cc1SJeff Dike */ 9531da177e4SLinus Torvalds if (fake_ide) 9541da177e4SLinus Torvalds make_ide_entries(ubd_gendisk[n]->disk_name); 9551da177e4SLinus Torvalds 956ec7cf783SJeff Dike err = 0; 957ec7cf783SJeff Dike out: 958ec7cf783SJeff Dike return err; 95962f96cb0SJeff Dike 9604e6da0feSRichard Weinberger out_cleanup_tags: 9614e6da0feSRichard Weinberger blk_mq_free_tag_set(&ubd_dev->tag_set); 96262f96cb0SJeff Dike out_cleanup: 96362f96cb0SJeff Dike blk_cleanup_queue(ubd_dev->queue); 96462f96cb0SJeff Dike goto out; 9651da177e4SLinus Torvalds } 9661da177e4SLinus Torvalds 967f28169d2SJeff Dike static int ubd_config(char *str, char **error_out) 9681da177e4SLinus Torvalds { 969e7f6552fSPaolo 'Blaisorblade' Giarrusso int n, ret; 9701da177e4SLinus Torvalds 971f28169d2SJeff Dike /* This string is possibly broken up and stored, so it's only 972f28169d2SJeff Dike * freed if ubd_setup_common fails, or if only general options 973f28169d2SJeff Dike * were set. 974f28169d2SJeff Dike */ 975970d6e3aSJeff Dike str = kstrdup(str, GFP_KERNEL); 9761da177e4SLinus Torvalds if (str == NULL) { 977f28169d2SJeff Dike *error_out = "Failed to allocate memory"; 978f28169d2SJeff Dike return -ENOMEM; 9791da177e4SLinus Torvalds } 980f28169d2SJeff Dike 981f28169d2SJeff Dike ret = ubd_setup_common(str, &n, error_out); 982f28169d2SJeff Dike if (ret) 983e7f6552fSPaolo 'Blaisorblade' Giarrusso goto err_free; 984f28169d2SJeff Dike 985e7f6552fSPaolo 'Blaisorblade' Giarrusso if (n == -1) { 986e7f6552fSPaolo 'Blaisorblade' Giarrusso ret = 0; 987d8d7c28eSPaolo 'Blaisorblade' Giarrusso goto err_free; 988e7f6552fSPaolo 'Blaisorblade' Giarrusso } 9891da177e4SLinus Torvalds 990d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 991f28169d2SJeff Dike ret = ubd_add(n, error_out); 992e7f6552fSPaolo 'Blaisorblade' Giarrusso if (ret) 9937d314e34SPaolo 'Blaisorblade' Giarrusso ubd_devs[n].file = NULL; 994d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 9951da177e4SLinus Torvalds 996e7f6552fSPaolo 'Blaisorblade' Giarrusso out: 997e7f6552fSPaolo 'Blaisorblade' Giarrusso return ret; 998e7f6552fSPaolo 'Blaisorblade' Giarrusso 999e7f6552fSPaolo 'Blaisorblade' Giarrusso err_free: 1000e7f6552fSPaolo 'Blaisorblade' Giarrusso kfree(str); 1001e7f6552fSPaolo 'Blaisorblade' Giarrusso goto out; 10021da177e4SLinus Torvalds } 10031da177e4SLinus Torvalds 10041da177e4SLinus Torvalds static int ubd_get_config(char *name, char *str, int size, char **error_out) 10051da177e4SLinus Torvalds { 10067d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 10071da177e4SLinus Torvalds int n, len = 0; 10081da177e4SLinus Torvalds 10091da177e4SLinus Torvalds n = parse_unit(&name); 10101da177e4SLinus Torvalds if((n >= MAX_DEV) || (n < 0)){ 10111da177e4SLinus Torvalds *error_out = "ubd_get_config : device number out of range"; 1012dc764e50SJeff Dike return -1; 10131da177e4SLinus Torvalds } 10141da177e4SLinus Torvalds 10157d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 1016d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10171da177e4SLinus Torvalds 10187d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL){ 10191da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, "", 1); 10201da177e4SLinus Torvalds goto out; 10211da177e4SLinus Torvalds } 10221da177e4SLinus Torvalds 10237d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); 10241da177e4SLinus Torvalds 10257d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL){ 10261da177e4SLinus Torvalds CONFIG_CHUNK(str, size, len, ",", 0); 10277d314e34SPaolo 'Blaisorblade' Giarrusso CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); 10281da177e4SLinus Torvalds } 10291da177e4SLinus Torvalds else CONFIG_CHUNK(str, size, len, "", 1); 10301da177e4SLinus Torvalds 10311da177e4SLinus Torvalds out: 1032d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 1033dc764e50SJeff Dike return len; 10341da177e4SLinus Torvalds } 10351da177e4SLinus Torvalds 103629d56cfeSJeff Dike static int ubd_id(char **str, int *start_out, int *end_out) 103729d56cfeSJeff Dike { 103829d56cfeSJeff Dike int n; 103929d56cfeSJeff Dike 104029d56cfeSJeff Dike n = parse_unit(str); 104129d56cfeSJeff Dike *start_out = 0; 104229d56cfeSJeff Dike *end_out = MAX_DEV - 1; 104329d56cfeSJeff Dike return n; 104429d56cfeSJeff Dike } 104529d56cfeSJeff Dike 1046f28169d2SJeff Dike static int ubd_remove(int n, char **error_out) 10471da177e4SLinus Torvalds { 10482e3f5251SJeff Dike struct gendisk *disk = ubd_gendisk[n]; 10497d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev; 105029d56cfeSJeff Dike int err = -ENODEV; 10511da177e4SLinus Torvalds 1052d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_lock(&ubd_lock); 10531da177e4SLinus Torvalds 10547d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev = &ubd_devs[n]; 105529d56cfeSJeff Dike 10567d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 105729d56cfeSJeff Dike goto out; 105829d56cfeSJeff Dike 105929d56cfeSJeff Dike /* you cannot remove a open disk */ 106029d56cfeSJeff Dike err = -EBUSY; 10617d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count > 0) 106229d56cfeSJeff Dike goto out; 106329d56cfeSJeff Dike 10641da177e4SLinus Torvalds ubd_gendisk[n] = NULL; 1065b47d2debSJeff Dike if(disk != NULL){ 1066b47d2debSJeff Dike del_gendisk(disk); 1067b47d2debSJeff Dike put_disk(disk); 1068b47d2debSJeff Dike } 10691da177e4SLinus Torvalds 10701da177e4SLinus Torvalds if(fake_gendisk[n] != NULL){ 10711da177e4SLinus Torvalds del_gendisk(fake_gendisk[n]); 10721da177e4SLinus Torvalds put_disk(fake_gendisk[n]); 10731da177e4SLinus Torvalds fake_gendisk[n] = NULL; 10741da177e4SLinus Torvalds } 10751da177e4SLinus Torvalds 10761da177e4SLinus Torvalds err = 0; 10772e3f5251SJeff Dike platform_device_unregister(&ubd_dev->pdev); 10781da177e4SLinus Torvalds out: 1079d7fb2c38SPaolo 'Blaisorblade' Giarrusso mutex_unlock(&ubd_lock); 108029d56cfeSJeff Dike return err; 10811da177e4SLinus Torvalds } 10821da177e4SLinus Torvalds 1083f28169d2SJeff Dike /* All these are called by mconsole in process context and without 1084b8831a1dSJeff Dike * ubd-specific locks. The structure itself is const except for .list. 1085f28169d2SJeff Dike */ 10861da177e4SLinus Torvalds static struct mc_device ubd_mc = { 108784f48d4fSJeff Dike .list = LIST_HEAD_INIT(ubd_mc.list), 10881da177e4SLinus Torvalds .name = "ubd", 10891da177e4SLinus Torvalds .config = ubd_config, 10901da177e4SLinus Torvalds .get_config = ubd_get_config, 109129d56cfeSJeff Dike .id = ubd_id, 10921da177e4SLinus Torvalds .remove = ubd_remove, 10931da177e4SLinus Torvalds }; 10941da177e4SLinus Torvalds 1095d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_mc_init(void) 10961da177e4SLinus Torvalds { 10971da177e4SLinus Torvalds mconsole_register_dev(&ubd_mc); 10981da177e4SLinus Torvalds return 0; 10991da177e4SLinus Torvalds } 11001da177e4SLinus Torvalds 11011da177e4SLinus Torvalds __initcall(ubd_mc_init); 11021da177e4SLinus Torvalds 1103d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd0_init(void) 1104d8d7c28eSPaolo 'Blaisorblade' Giarrusso { 1105d8d7c28eSPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = &ubd_devs[0]; 1106d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1107b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1108d8d7c28eSPaolo 'Blaisorblade' Giarrusso if(ubd_dev->file == NULL) 1109d8d7c28eSPaolo 'Blaisorblade' Giarrusso ubd_dev->file = "root_fs"; 1110b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 1111b8831a1dSJeff Dike 1112dc764e50SJeff Dike return 0; 1113d8d7c28eSPaolo 'Blaisorblade' Giarrusso } 1114d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1115d8d7c28eSPaolo 'Blaisorblade' Giarrusso __initcall(ubd0_init); 1116d8d7c28eSPaolo 'Blaisorblade' Giarrusso 1117b8831a1dSJeff Dike /* Used in ubd_init, which is an initcall */ 11183ae5eaecSRussell King static struct platform_driver ubd_driver = { 11193ae5eaecSRussell King .driver = { 11201da177e4SLinus Torvalds .name = DRIVER_NAME, 11213ae5eaecSRussell King }, 11221da177e4SLinus Torvalds }; 11231da177e4SLinus Torvalds 1124d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_init(void) 11251da177e4SLinus Torvalds { 1126f28169d2SJeff Dike char *error; 1127f28169d2SJeff Dike int i, err; 11281da177e4SLinus Torvalds 1129792dd4fcSChristoph Hellwig if (register_blkdev(UBD_MAJOR, "ubd")) 11301da177e4SLinus Torvalds return -1; 11311da177e4SLinus Torvalds 1132792dd4fcSChristoph Hellwig if (fake_major != UBD_MAJOR) { 11331da177e4SLinus Torvalds char name[sizeof("ubd_nnn\0")]; 11341da177e4SLinus Torvalds 11351da177e4SLinus Torvalds snprintf(name, sizeof(name), "ubd_%d", fake_major); 11361da177e4SLinus Torvalds if (register_blkdev(fake_major, "ubd")) 11371da177e4SLinus Torvalds return -1; 11381da177e4SLinus Torvalds } 1139f88f0bdfSAnton Ivanov 11406da2ec56SKees Cook irq_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11416da2ec56SKees Cook sizeof(struct io_thread_req *), 1142f88f0bdfSAnton Ivanov GFP_KERNEL 1143f88f0bdfSAnton Ivanov ); 1144f88f0bdfSAnton Ivanov irq_remainder = 0; 1145f88f0bdfSAnton Ivanov 1146f88f0bdfSAnton Ivanov if (irq_req_buffer == NULL) { 1147f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1148f88f0bdfSAnton Ivanov return -1; 1149f88f0bdfSAnton Ivanov } 11506da2ec56SKees Cook io_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, 11516da2ec56SKees Cook sizeof(struct io_thread_req *), 1152f88f0bdfSAnton Ivanov GFP_KERNEL 1153f88f0bdfSAnton Ivanov ); 1154f88f0bdfSAnton Ivanov 1155f88f0bdfSAnton Ivanov io_remainder = 0; 1156f88f0bdfSAnton Ivanov 1157f88f0bdfSAnton Ivanov if (io_req_buffer == NULL) { 1158f88f0bdfSAnton Ivanov printk(KERN_ERR "Failed to initialize ubd buffering\n"); 1159f88f0bdfSAnton Ivanov return -1; 1160f88f0bdfSAnton Ivanov } 11613ae5eaecSRussell King platform_driver_register(&ubd_driver); 1162b8831a1dSJeff Dike mutex_lock(&ubd_lock); 1163f28169d2SJeff Dike for (i = 0; i < MAX_DEV; i++){ 1164f28169d2SJeff Dike err = ubd_add(i, &error); 1165f28169d2SJeff Dike if(err) 1166f28169d2SJeff Dike printk(KERN_ERR "Failed to initialize ubd device %d :" 1167f28169d2SJeff Dike "%s\n", i, error); 1168f28169d2SJeff Dike } 1169b8831a1dSJeff Dike mutex_unlock(&ubd_lock); 11701da177e4SLinus Torvalds return 0; 11711da177e4SLinus Torvalds } 11721da177e4SLinus Torvalds 11731da177e4SLinus Torvalds late_initcall(ubd_init); 11741da177e4SLinus Torvalds 1175d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int __init ubd_driver_init(void){ 117691acb21fSJeff Dike unsigned long stack; 117791acb21fSJeff Dike int err; 117891acb21fSJeff Dike 117991acb21fSJeff Dike /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ 118091acb21fSJeff Dike if(global_openflags.s){ 118191acb21fSJeff Dike printk(KERN_INFO "ubd: Synchronous mode\n"); 118291acb21fSJeff Dike /* Letting ubd=sync be like using ubd#s= instead of ubd#= is 118391acb21fSJeff Dike * enough. So use anyway the io thread. */ 118491acb21fSJeff Dike } 118591acb21fSJeff Dike stack = alloc_stack(0, 0); 118691acb21fSJeff Dike io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), 118791acb21fSJeff Dike &thread_fd); 118891acb21fSJeff Dike if(io_pid < 0){ 118991acb21fSJeff Dike printk(KERN_ERR 119091acb21fSJeff Dike "ubd : Failed to start I/O thread (errno = %d) - " 119191acb21fSJeff Dike "falling back to synchronous I/O\n", -io_pid); 119291acb21fSJeff Dike io_pid = -1; 1193dc764e50SJeff Dike return 0; 119491acb21fSJeff Dike } 119591acb21fSJeff Dike err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, 1196c0b79a90SYong Zhang 0, "ubd", ubd_devs); 119791acb21fSJeff Dike if(err != 0) 119891acb21fSJeff Dike printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); 1199f4c57a78SJeff Dike return 0; 120091acb21fSJeff Dike } 120191acb21fSJeff Dike 120291acb21fSJeff Dike device_initcall(ubd_driver_init); 120391acb21fSJeff Dike 1204a625c998SAl Viro static int ubd_open(struct block_device *bdev, fmode_t mode) 12051da177e4SLinus Torvalds { 1206a625c998SAl Viro struct gendisk *disk = bdev->bd_disk; 12077d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12081da177e4SLinus Torvalds int err = 0; 12091da177e4SLinus Torvalds 12109a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12117d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->count == 0){ 12127d314e34SPaolo 'Blaisorblade' Giarrusso err = ubd_open_dev(ubd_dev); 12131da177e4SLinus Torvalds if(err){ 12141da177e4SLinus Torvalds printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", 12157d314e34SPaolo 'Blaisorblade' Giarrusso disk->disk_name, ubd_dev->file, -err); 12161da177e4SLinus Torvalds goto out; 12171da177e4SLinus Torvalds } 12181da177e4SLinus Torvalds } 12197d314e34SPaolo 'Blaisorblade' Giarrusso ubd_dev->count++; 12207d314e34SPaolo 'Blaisorblade' Giarrusso set_disk_ro(disk, !ubd_dev->openflags.w); 12212c49be99SPaolo 'Blaisorblade' Giarrusso 12222c49be99SPaolo 'Blaisorblade' Giarrusso /* This should no more be needed. And it didn't work anyway to exclude 12232c49be99SPaolo 'Blaisorblade' Giarrusso * read-write remounting of filesystems.*/ 1224a625c998SAl Viro /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ 12255f75a4f8SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); 12261da177e4SLinus Torvalds err = -EROFS; 12272c49be99SPaolo 'Blaisorblade' Giarrusso }*/ 12281da177e4SLinus Torvalds out: 12299a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 1230dc764e50SJeff Dike return err; 12311da177e4SLinus Torvalds } 12321da177e4SLinus Torvalds 1233db2a144bSAl Viro static void ubd_release(struct gendisk *disk, fmode_t mode) 12341da177e4SLinus Torvalds { 12357d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 12361da177e4SLinus Torvalds 12379a181c58SArnd Bergmann mutex_lock(&ubd_mutex); 12387d314e34SPaolo 'Blaisorblade' Giarrusso if(--ubd_dev->count == 0) 12395f75a4f8SPaolo 'Blaisorblade' Giarrusso ubd_close_dev(ubd_dev); 12409a181c58SArnd Bergmann mutex_unlock(&ubd_mutex); 12411da177e4SLinus Torvalds } 12421da177e4SLinus Torvalds 124391acb21fSJeff Dike static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, 124491acb21fSJeff Dike __u64 *cow_offset, unsigned long *bitmap, 124591acb21fSJeff Dike __u64 bitmap_offset, unsigned long *bitmap_words, 124691acb21fSJeff Dike __u64 bitmap_len) 12471da177e4SLinus Torvalds { 124891acb21fSJeff Dike __u64 sector = io_offset >> 9; 124991acb21fSJeff Dike int i, update_bitmap = 0; 12501da177e4SLinus Torvalds 125191acb21fSJeff Dike for(i = 0; i < length >> 9; i++){ 125291acb21fSJeff Dike if(cow_mask != NULL) 125391acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) cow_mask); 125491acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 125509ace81cSJeff Dike continue; 12561da177e4SLinus Torvalds 125791acb21fSJeff Dike update_bitmap = 1; 125891acb21fSJeff Dike ubd_set_bit(sector + i, (unsigned char *) bitmap); 12591da177e4SLinus Torvalds } 126091acb21fSJeff Dike 126191acb21fSJeff Dike if(!update_bitmap) 126291acb21fSJeff Dike return; 126391acb21fSJeff Dike 126491acb21fSJeff Dike *cow_offset = sector / (sizeof(unsigned long) * 8); 126591acb21fSJeff Dike 126691acb21fSJeff Dike /* This takes care of the case where we're exactly at the end of the 126791acb21fSJeff Dike * device, and *cow_offset + 1 is off the end. So, just back it up 126891acb21fSJeff Dike * by one word. Thanks to Lynn Kerby for the fix and James McMechan 126991acb21fSJeff Dike * for the original diagnosis. 127091acb21fSJeff Dike */ 12716d074242SJiri Olsa if (*cow_offset == (DIV_ROUND_UP(bitmap_len, 12726d074242SJiri Olsa sizeof(unsigned long)) - 1)) 127391acb21fSJeff Dike (*cow_offset)--; 127491acb21fSJeff Dike 127591acb21fSJeff Dike bitmap_words[0] = bitmap[*cow_offset]; 127691acb21fSJeff Dike bitmap_words[1] = bitmap[*cow_offset + 1]; 127791acb21fSJeff Dike 127891acb21fSJeff Dike *cow_offset *= sizeof(unsigned long); 127991acb21fSJeff Dike *cow_offset += bitmap_offset; 128091acb21fSJeff Dike } 128191acb21fSJeff Dike 128291acb21fSJeff Dike static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, 128391acb21fSJeff Dike __u64 bitmap_offset, __u64 bitmap_len) 128491acb21fSJeff Dike { 128591acb21fSJeff Dike __u64 sector = req->offset >> 9; 128691acb21fSJeff Dike int i; 128791acb21fSJeff Dike 128891acb21fSJeff Dike if(req->length > (sizeof(req->sector_mask) * 8) << 9) 128991acb21fSJeff Dike panic("Operation too long"); 129091acb21fSJeff Dike 129191acb21fSJeff Dike if(req->op == UBD_READ) { 129291acb21fSJeff Dike for(i = 0; i < req->length >> 9; i++){ 129391acb21fSJeff Dike if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) 129491acb21fSJeff Dike ubd_set_bit(i, (unsigned char *) 129591acb21fSJeff Dike &req->sector_mask); 129691acb21fSJeff Dike } 129791acb21fSJeff Dike } 129891acb21fSJeff Dike else cowify_bitmap(req->offset, req->length, &req->sector_mask, 129991acb21fSJeff Dike &req->cow_offset, bitmap, bitmap_offset, 130091acb21fSJeff Dike req->bitmap_words, bitmap_len); 13011da177e4SLinus Torvalds } 13021da177e4SLinus Torvalds 130362f96cb0SJeff Dike /* Called with dev->lock held */ 1304a0044bdfSJeff Dike static void prepare_request(struct request *req, struct io_thread_req *io_req, 1305a0044bdfSJeff Dike unsigned long long offset, int page_offset, 1306a0044bdfSJeff Dike int len, struct page *page) 13071da177e4SLinus Torvalds { 13081da177e4SLinus Torvalds struct gendisk *disk = req->rq_disk; 13097d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = disk->private_data; 131091acb21fSJeff Dike 131162f96cb0SJeff Dike io_req->req = req; 1312a0044bdfSJeff Dike io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : 1313a0044bdfSJeff Dike ubd_dev->fd; 13147d314e34SPaolo 'Blaisorblade' Giarrusso io_req->fds[1] = ubd_dev->fd; 131591acb21fSJeff Dike io_req->cow_offset = -1; 13161da177e4SLinus Torvalds io_req->offset = offset; 13171da177e4SLinus Torvalds io_req->length = len; 13181da177e4SLinus Torvalds io_req->error = 0; 131991acb21fSJeff Dike io_req->sector_mask = 0; 132091acb21fSJeff Dike 132191acb21fSJeff Dike io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; 13221da177e4SLinus Torvalds io_req->offsets[0] = 0; 13237d314e34SPaolo 'Blaisorblade' Giarrusso io_req->offsets[1] = ubd_dev->cow.data_offset; 1324a0044bdfSJeff Dike io_req->buffer = page_address(page) + page_offset; 13251da177e4SLinus Torvalds io_req->sectorsize = 1 << 9; 13261da177e4SLinus Torvalds 13277d314e34SPaolo 'Blaisorblade' Giarrusso if(ubd_dev->cow.file != NULL) 1328a0044bdfSJeff Dike cowify_req(io_req, ubd_dev->cow.bitmap, 1329a0044bdfSJeff Dike ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); 133091acb21fSJeff Dike 13311da177e4SLinus Torvalds } 13321da177e4SLinus Torvalds 133362f96cb0SJeff Dike /* Called with dev->lock held */ 1334805f11a0SRichard Weinberger static void prepare_flush_request(struct request *req, 1335805f11a0SRichard Weinberger struct io_thread_req *io_req) 1336805f11a0SRichard Weinberger { 1337805f11a0SRichard Weinberger struct gendisk *disk = req->rq_disk; 1338805f11a0SRichard Weinberger struct ubd *ubd_dev = disk->private_data; 1339805f11a0SRichard Weinberger 1340805f11a0SRichard Weinberger io_req->req = req; 1341805f11a0SRichard Weinberger io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : 1342805f11a0SRichard Weinberger ubd_dev->fd; 1343805f11a0SRichard Weinberger io_req->op = UBD_FLUSH; 1344805f11a0SRichard Weinberger } 1345805f11a0SRichard Weinberger 13464e6da0feSRichard Weinberger static void submit_request(struct io_thread_req *io_req, struct ubd *dev) 1347bc1d72e7SRichard Weinberger { 1348bc1d72e7SRichard Weinberger int n = os_write_file(thread_fd, &io_req, 1349bc1d72e7SRichard Weinberger sizeof(io_req)); 13504e6da0feSRichard Weinberger 1351bc1d72e7SRichard Weinberger if (n != sizeof(io_req)) { 1352bc1d72e7SRichard Weinberger if (n != -EAGAIN) 13534e6da0feSRichard Weinberger pr_err("write to io thread failed: %d\n", -n); 1354bc1d72e7SRichard Weinberger 13554e6da0feSRichard Weinberger blk_mq_requeue_request(io_req->req, true); 1356bc1d72e7SRichard Weinberger kfree(io_req); 1357bc1d72e7SRichard Weinberger } 1358bc1d72e7SRichard Weinberger } 1359bc1d72e7SRichard Weinberger 13604e6da0feSRichard Weinberger static blk_status_t ubd_queue_rq(struct blk_mq_hw_ctx *hctx, 13614e6da0feSRichard Weinberger const struct blk_mq_queue_data *bd) 13621da177e4SLinus Torvalds { 13634e6da0feSRichard Weinberger struct request *req = bd->rq; 13644e6da0feSRichard Weinberger struct ubd *dev = hctx->queue->queuedata; 13654e6da0feSRichard Weinberger struct ubd_pdu *pdu = blk_mq_rq_to_pdu(req); 13662adcec21SJeff Dike struct io_thread_req *io_req; 13671da177e4SLinus Torvalds 13684e6da0feSRichard Weinberger blk_mq_start_request(req); 1369a0044bdfSJeff Dike 13704e6da0feSRichard Weinberger pdu->rq_pos = blk_rq_pos(req); 13714e6da0feSRichard Weinberger pdu->start_sg = 0; 13724e6da0feSRichard Weinberger pdu->end_sg = blk_rq_map_sg(req->q, req, pdu->sg); 1373805f11a0SRichard Weinberger 13743a5e02ceSMike Christie if (req_op(req) == REQ_OP_FLUSH) { 13754e6da0feSRichard Weinberger io_req = kmalloc(sizeof(struct io_thread_req), GFP_ATOMIC); 1376805f11a0SRichard Weinberger if (io_req == NULL) { 13774e6da0feSRichard Weinberger blk_mq_requeue_request(req, true); 13784e6da0feSRichard Weinberger goto done; 1379805f11a0SRichard Weinberger } 1380805f11a0SRichard Weinberger prepare_flush_request(req, io_req); 13814e6da0feSRichard Weinberger submit_request(io_req, dev); 13824e6da0feSRichard Weinberger 13834e6da0feSRichard Weinberger goto done; 1384805f11a0SRichard Weinberger } 1385805f11a0SRichard Weinberger 13864e6da0feSRichard Weinberger while (pdu->start_sg < pdu->end_sg) { 13874e6da0feSRichard Weinberger struct scatterlist *sg = &pdu->sg[pdu->start_sg]; 1388a0044bdfSJeff Dike 13892adcec21SJeff Dike io_req = kmalloc(sizeof(struct io_thread_req), 1390990c5587SPeter Zijlstra GFP_ATOMIC); 13912adcec21SJeff Dike if (io_req == NULL) { 13924e6da0feSRichard Weinberger blk_mq_requeue_request(req, true); 13934e6da0feSRichard Weinberger goto done; 13942adcec21SJeff Dike } 13952adcec21SJeff Dike prepare_request(req, io_req, 13964e6da0feSRichard Weinberger (unsigned long long)pdu->rq_pos << 9, 139745711f1aSJens Axboe sg->offset, sg->length, sg_page(sg)); 1398a0044bdfSJeff Dike 13994e6da0feSRichard Weinberger submit_request(io_req, dev); 1400a0044bdfSJeff Dike 14014e6da0feSRichard Weinberger pdu->rq_pos += sg->length >> 9; 14024e6da0feSRichard Weinberger pdu->start_sg++; 1403a0044bdfSJeff Dike } 14044e6da0feSRichard Weinberger 14054e6da0feSRichard Weinberger done: 14064e6da0feSRichard Weinberger return BLK_STS_OK; 140791acb21fSJeff Dike } 14084e6da0feSRichard Weinberger 14094e6da0feSRichard Weinberger static int ubd_init_request(struct blk_mq_tag_set *set, 14104e6da0feSRichard Weinberger struct request *req, unsigned int hctx_idx, 14114e6da0feSRichard Weinberger unsigned int numa_node) 14124e6da0feSRichard Weinberger { 14134e6da0feSRichard Weinberger struct ubd_pdu *pdu = blk_mq_rq_to_pdu(req); 14144e6da0feSRichard Weinberger 14154e6da0feSRichard Weinberger sg_init_table(pdu->sg, MAX_SG); 14164e6da0feSRichard Weinberger 14174e6da0feSRichard Weinberger return 0; 14181da177e4SLinus Torvalds } 14191da177e4SLinus Torvalds 1420a885c8c4SChristoph Hellwig static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 1421a885c8c4SChristoph Hellwig { 14227d314e34SPaolo 'Blaisorblade' Giarrusso struct ubd *ubd_dev = bdev->bd_disk->private_data; 1423a885c8c4SChristoph Hellwig 1424a885c8c4SChristoph Hellwig geo->heads = 128; 1425a885c8c4SChristoph Hellwig geo->sectors = 32; 14267d314e34SPaolo 'Blaisorblade' Giarrusso geo->cylinders = ubd_dev->size / (128 * 32 * 512); 1427a885c8c4SChristoph Hellwig return 0; 1428a885c8c4SChristoph Hellwig } 1429a885c8c4SChristoph Hellwig 1430a625c998SAl Viro static int ubd_ioctl(struct block_device *bdev, fmode_t mode, 14311da177e4SLinus Torvalds unsigned int cmd, unsigned long arg) 14321da177e4SLinus Torvalds { 1433a625c998SAl Viro struct ubd *ubd_dev = bdev->bd_disk->private_data; 143473855e13SBartlomiej Zolnierkiewicz u16 ubd_id[ATA_ID_WORDS]; 14351da177e4SLinus Torvalds 14361da177e4SLinus Torvalds switch (cmd) { 14371da177e4SLinus Torvalds struct cdrom_volctrl volume; 14381da177e4SLinus Torvalds case HDIO_GET_IDENTITY: 143973855e13SBartlomiej Zolnierkiewicz memset(&ubd_id, 0, ATA_ID_WORDS * 2); 144073855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); 144173855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_HEADS] = 128; 144273855e13SBartlomiej Zolnierkiewicz ubd_id[ATA_ID_SECTORS] = 32; 14431da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, (char *) &ubd_id, 14441da177e4SLinus Torvalds sizeof(ubd_id))) 1445dc764e50SJeff Dike return -EFAULT; 1446dc764e50SJeff Dike return 0; 14471da177e4SLinus Torvalds 14481da177e4SLinus Torvalds case CDROMVOLREAD: 14491da177e4SLinus Torvalds if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) 1450dc764e50SJeff Dike return -EFAULT; 14511da177e4SLinus Torvalds volume.channel0 = 255; 14521da177e4SLinus Torvalds volume.channel1 = 255; 14531da177e4SLinus Torvalds volume.channel2 = 255; 14541da177e4SLinus Torvalds volume.channel3 = 255; 14551da177e4SLinus Torvalds if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) 1456dc764e50SJeff Dike return -EFAULT; 1457dc764e50SJeff Dike return 0; 14581da177e4SLinus Torvalds } 1459dc764e50SJeff Dike return -EINVAL; 14601da177e4SLinus Torvalds } 14611da177e4SLinus Torvalds 146291acb21fSJeff Dike static int update_bitmap(struct io_thread_req *req) 14631da177e4SLinus Torvalds { 146491acb21fSJeff Dike int n; 146591acb21fSJeff Dike 146691acb21fSJeff Dike if(req->cow_offset == -1) 1467dc764e50SJeff Dike return 0; 146891acb21fSJeff Dike 14698c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[1], &req->bitmap_words, 14708c6157b6SAnton Ivanov sizeof(req->bitmap_words), req->cow_offset); 147191acb21fSJeff Dike if(n != sizeof(req->bitmap_words)){ 147291acb21fSJeff Dike printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, 147391acb21fSJeff Dike req->fds[1]); 1474dc764e50SJeff Dike return 1; 147591acb21fSJeff Dike } 147691acb21fSJeff Dike 1477dc764e50SJeff Dike return 0; 147891acb21fSJeff Dike } 147991acb21fSJeff Dike 14805dc62b1bSWANG Cong static void do_io(struct io_thread_req *req) 148191acb21fSJeff Dike { 14821da177e4SLinus Torvalds char *buf; 148391acb21fSJeff Dike unsigned long len; 148491acb21fSJeff Dike int n, nsectors, start, end, bit; 14851da177e4SLinus Torvalds __u64 off; 14861da177e4SLinus Torvalds 1487805f11a0SRichard Weinberger if (req->op == UBD_FLUSH) { 1488805f11a0SRichard Weinberger /* fds[0] is always either the rw image or our cow file */ 1489805f11a0SRichard Weinberger n = os_sync_file(req->fds[0]); 1490805f11a0SRichard Weinberger if (n != 0) { 1491805f11a0SRichard Weinberger printk("do_io - sync failed err = %d " 1492805f11a0SRichard Weinberger "fd = %d\n", -n, req->fds[0]); 1493805f11a0SRichard Weinberger req->error = 1; 1494805f11a0SRichard Weinberger } 1495805f11a0SRichard Weinberger return; 1496805f11a0SRichard Weinberger } 1497805f11a0SRichard Weinberger 14981da177e4SLinus Torvalds nsectors = req->length / req->sectorsize; 14991da177e4SLinus Torvalds start = 0; 15001da177e4SLinus Torvalds do { 150191acb21fSJeff Dike bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); 15021da177e4SLinus Torvalds end = start; 15031da177e4SLinus Torvalds while((end < nsectors) && 150491acb21fSJeff Dike (ubd_test_bit(end, (unsigned char *) 150591acb21fSJeff Dike &req->sector_mask) == bit)) 15061da177e4SLinus Torvalds end++; 15071da177e4SLinus Torvalds 150891acb21fSJeff Dike off = req->offset + req->offsets[bit] + 15091da177e4SLinus Torvalds start * req->sectorsize; 15101da177e4SLinus Torvalds len = (end - start) * req->sectorsize; 15111da177e4SLinus Torvalds buf = &req->buffer[start * req->sectorsize]; 15121da177e4SLinus Torvalds 151391acb21fSJeff Dike if(req->op == UBD_READ){ 151491acb21fSJeff Dike n = 0; 151591acb21fSJeff Dike do { 151691acb21fSJeff Dike buf = &buf[n]; 151791acb21fSJeff Dike len -= n; 15188c6157b6SAnton Ivanov n = os_pread_file(req->fds[bit], buf, len, off); 151991acb21fSJeff Dike if (n < 0) { 152091acb21fSJeff Dike printk("do_io - read failed, err = %d " 152191acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 15221da177e4SLinus Torvalds req->error = 1; 15231da177e4SLinus Torvalds return; 15241da177e4SLinus Torvalds } 152591acb21fSJeff Dike } while((n < len) && (n != 0)); 152691acb21fSJeff Dike if (n < len) memset(&buf[n], 0, len - n); 152791acb21fSJeff Dike } else { 15288c6157b6SAnton Ivanov n = os_pwrite_file(req->fds[bit], buf, len, off); 152991acb21fSJeff Dike if(n != len){ 153091acb21fSJeff Dike printk("do_io - write failed err = %d " 153191acb21fSJeff Dike "fd = %d\n", -n, req->fds[bit]); 153291acb21fSJeff Dike req->error = 1; 153391acb21fSJeff Dike return; 153491acb21fSJeff Dike } 153591acb21fSJeff Dike } 15361da177e4SLinus Torvalds 15371da177e4SLinus Torvalds start = end; 15381da177e4SLinus Torvalds } while(start < nsectors); 153991acb21fSJeff Dike 154091acb21fSJeff Dike req->error = update_bitmap(req); 15411da177e4SLinus Torvalds } 154291acb21fSJeff Dike 154391acb21fSJeff Dike /* Changed in start_io_thread, which is serialized by being called only 154491acb21fSJeff Dike * from ubd_init, which is an initcall. 154591acb21fSJeff Dike */ 154691acb21fSJeff Dike int kernel_fd = -1; 154791acb21fSJeff Dike 1548d8d7c28eSPaolo 'Blaisorblade' Giarrusso /* Only changed by the io thread. XXX: currently unused. */ 1549d8d7c28eSPaolo 'Blaisorblade' Giarrusso static int io_count = 0; 155091acb21fSJeff Dike 155191acb21fSJeff Dike int io_thread(void *arg) 155291acb21fSJeff Dike { 1553f88f0bdfSAnton Ivanov int n, count, written, res; 155491acb21fSJeff Dike 155591d44ff8SRichard Weinberger os_fix_helper_signals(); 155691d44ff8SRichard Weinberger 155791acb21fSJeff Dike while(1){ 1558f88f0bdfSAnton Ivanov n = bulk_req_safe_read( 1559f88f0bdfSAnton Ivanov kernel_fd, 1560f88f0bdfSAnton Ivanov io_req_buffer, 1561f88f0bdfSAnton Ivanov &io_remainder, 1562f88f0bdfSAnton Ivanov &io_remainder_size, 1563f88f0bdfSAnton Ivanov UBD_REQ_BUFFER_SIZE 1564f88f0bdfSAnton Ivanov ); 1565f88f0bdfSAnton Ivanov if (n < 0) { 1566f88f0bdfSAnton Ivanov if (n == -EAGAIN) { 1567f88f0bdfSAnton Ivanov ubd_read_poll(-1); 1568f88f0bdfSAnton Ivanov continue; 1569f88f0bdfSAnton Ivanov } else { 1570f88f0bdfSAnton Ivanov printk("io_thread - read failed, fd = %d, " 1571f88f0bdfSAnton Ivanov "err = %d," 1572f88f0bdfSAnton Ivanov "reminder = %d\n", 1573f88f0bdfSAnton Ivanov kernel_fd, -n, io_remainder_size); 1574f88f0bdfSAnton Ivanov } 1575f88f0bdfSAnton Ivanov } 1576f88f0bdfSAnton Ivanov 1577f88f0bdfSAnton Ivanov for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { 1578f88f0bdfSAnton Ivanov io_count++; 1579f88f0bdfSAnton Ivanov do_io((*io_req_buffer)[count]); 1580f88f0bdfSAnton Ivanov } 1581f88f0bdfSAnton Ivanov 1582f88f0bdfSAnton Ivanov written = 0; 1583f88f0bdfSAnton Ivanov 1584f88f0bdfSAnton Ivanov do { 1585f88f0bdfSAnton Ivanov res = os_write_file(kernel_fd, ((char *) io_req_buffer) + written, n); 1586ff6a1798SAnton Ivanov if (res >= 0) { 1587f88f0bdfSAnton Ivanov written += res; 1588f88f0bdfSAnton Ivanov } else { 1589f88f0bdfSAnton Ivanov if (res != -EAGAIN) { 1590ff6a1798SAnton Ivanov printk("io_thread - write failed, fd = %d, " 159191acb21fSJeff Dike "err = %d\n", kernel_fd, -n); 159291acb21fSJeff Dike } 159391acb21fSJeff Dike } 1594f88f0bdfSAnton Ivanov if (written < n) { 1595f88f0bdfSAnton Ivanov ubd_write_poll(-1); 1596f88f0bdfSAnton Ivanov } 1597f88f0bdfSAnton Ivanov } while (written < n); 159891acb21fSJeff Dike } 159991acb21fSJeff Dike 16001b57e9c2SJeff Dike return 0; 16011b57e9c2SJeff Dike } 1602