16cbd5570SChris Mason /* 26cbd5570SChris Mason * Copyright (C) 2007 Oracle. All rights reserved. 36cbd5570SChris Mason * 46cbd5570SChris Mason * This program is free software; you can redistribute it and/or 56cbd5570SChris Mason * modify it under the terms of the GNU General Public 66cbd5570SChris Mason * License v2 as published by the Free Software Foundation. 76cbd5570SChris Mason * 86cbd5570SChris Mason * This program is distributed in the hope that it will be useful, 96cbd5570SChris Mason * but WITHOUT ANY WARRANTY; without even the implied warranty of 106cbd5570SChris Mason * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 116cbd5570SChris Mason * General Public License for more details. 126cbd5570SChris Mason * 136cbd5570SChris Mason * You should have received a copy of the GNU General Public 146cbd5570SChris Mason * License along with this program; if not, write to the 156cbd5570SChris Mason * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 166cbd5570SChris Mason * Boston, MA 021110-1307, USA. 176cbd5570SChris Mason */ 186cbd5570SChris Mason 194b82d6e4SYan #include <linux/blkdev.h> 202e635a27SChris Mason #include <linux/module.h> 21e20d96d6SChris Mason #include <linux/buffer_head.h> 222e635a27SChris Mason #include <linux/fs.h> 232e635a27SChris Mason #include <linux/pagemap.h> 242e635a27SChris Mason #include <linux/highmem.h> 252e635a27SChris Mason #include <linux/time.h> 262e635a27SChris Mason #include <linux/init.h> 27a9572a15SEric Paris #include <linux/seq_file.h> 282e635a27SChris Mason #include <linux/string.h> 292e635a27SChris Mason #include <linux/backing-dev.h> 304b82d6e4SYan #include <linux/mount.h> 31dee26a9fSChris Mason #include <linux/mpage.h> 3275dfe396SChris Mason #include <linux/swap.h> 3375dfe396SChris Mason #include <linux/writeback.h> 348fd17795SChris Mason #include <linux/statfs.h> 3508607c1bSChris Mason #include <linux/compat.h> 3695e05289SChris Mason #include <linux/parser.h> 37c59f8951SChris Mason #include <linux/ctype.h> 386da6abaeSChris Mason #include <linux/namei.h> 39a9218f6bSChris Mason #include <linux/miscdevice.h> 401bcbf313SQinghuang Feng #include <linux/magic.h> 415a0e3ad6STejun Heo #include <linux/slab.h> 4290a887c9SDan Magenheimer #include <linux/cleancache.h> 4322c44fe6SJosef Bacik #include <linux/ratelimit.h> 444b4e25f2SChris Mason #include "compat.h" 4516cdcec7SMiao Xie #include "delayed-inode.h" 462e635a27SChris Mason #include "ctree.h" 47e20d96d6SChris Mason #include "disk-io.h" 48d5719762SChris Mason #include "transaction.h" 492c90e5d6SChris Mason #include "btrfs_inode.h" 50c5739bbaSChris Mason #include "ioctl.h" 513a686375SChris Mason #include "print-tree.h" 525103e947SJosef Bacik #include "xattr.h" 538a4b83ccSChris Mason #include "volumes.h" 54b3c3da71SChris Mason #include "version.h" 55be6e8dc0SBalaji Rao #include "export.h" 56c8b97818SChris Mason #include "compression.h" 572e635a27SChris Mason 581abe9b8aSliubo #define CREATE_TRACE_POINTS 591abe9b8aSliubo #include <trace/events/btrfs.h> 601abe9b8aSliubo 61b87221deSAlexey Dobriyan static const struct super_operations btrfs_super_ops; 62830c4adbSJosef Bacik static struct file_system_type btrfs_fs_type; 63e20d96d6SChris Mason 64acce952bSliubo static const char *btrfs_decode_error(struct btrfs_fs_info *fs_info, int errno, 65acce952bSliubo char nbuf[16]) 66acce952bSliubo { 67acce952bSliubo char *errstr = NULL; 68acce952bSliubo 69acce952bSliubo switch (errno) { 70acce952bSliubo case -EIO: 71acce952bSliubo errstr = "IO failure"; 72acce952bSliubo break; 73acce952bSliubo case -ENOMEM: 74acce952bSliubo errstr = "Out of memory"; 75acce952bSliubo break; 76acce952bSliubo case -EROFS: 77acce952bSliubo errstr = "Readonly filesystem"; 78acce952bSliubo break; 79acce952bSliubo default: 80acce952bSliubo if (nbuf) { 81acce952bSliubo if (snprintf(nbuf, 16, "error %d", -errno) >= 0) 82acce952bSliubo errstr = nbuf; 83acce952bSliubo } 84acce952bSliubo break; 85acce952bSliubo } 86acce952bSliubo 87acce952bSliubo return errstr; 88acce952bSliubo } 89acce952bSliubo 90acce952bSliubo static void __save_error_info(struct btrfs_fs_info *fs_info) 91acce952bSliubo { 92acce952bSliubo /* 93acce952bSliubo * today we only save the error info into ram. Long term we'll 94acce952bSliubo * also send it down to the disk 95acce952bSliubo */ 96acce952bSliubo fs_info->fs_state = BTRFS_SUPER_FLAG_ERROR; 97acce952bSliubo } 98acce952bSliubo 99acce952bSliubo /* NOTE: 100acce952bSliubo * We move write_super stuff at umount in order to avoid deadlock 101acce952bSliubo * for umount hold all lock. 102acce952bSliubo */ 103acce952bSliubo static void save_error_info(struct btrfs_fs_info *fs_info) 104acce952bSliubo { 105acce952bSliubo __save_error_info(fs_info); 106acce952bSliubo } 107acce952bSliubo 108acce952bSliubo /* btrfs handle error by forcing the filesystem readonly */ 109acce952bSliubo static void btrfs_handle_error(struct btrfs_fs_info *fs_info) 110acce952bSliubo { 111acce952bSliubo struct super_block *sb = fs_info->sb; 112acce952bSliubo 113acce952bSliubo if (sb->s_flags & MS_RDONLY) 114acce952bSliubo return; 115acce952bSliubo 116acce952bSliubo if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) { 117acce952bSliubo sb->s_flags |= MS_RDONLY; 118acce952bSliubo printk(KERN_INFO "btrfs is forced readonly\n"); 119acce952bSliubo } 120acce952bSliubo } 121acce952bSliubo 122acce952bSliubo /* 123acce952bSliubo * __btrfs_std_error decodes expected errors from the caller and 124acce952bSliubo * invokes the approciate error response. 125acce952bSliubo */ 126acce952bSliubo void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function, 127acce952bSliubo unsigned int line, int errno) 128acce952bSliubo { 129acce952bSliubo struct super_block *sb = fs_info->sb; 130acce952bSliubo char nbuf[16]; 131acce952bSliubo const char *errstr; 132acce952bSliubo 133acce952bSliubo /* 134acce952bSliubo * Special case: if the error is EROFS, and we're already 135acce952bSliubo * under MS_RDONLY, then it is safe here. 136acce952bSliubo */ 137acce952bSliubo if (errno == -EROFS && (sb->s_flags & MS_RDONLY)) 138acce952bSliubo return; 139acce952bSliubo 140acce952bSliubo errstr = btrfs_decode_error(fs_info, errno, nbuf); 141acce952bSliubo printk(KERN_CRIT "BTRFS error (device %s) in %s:%d: %s\n", 142acce952bSliubo sb->s_id, function, line, errstr); 143acce952bSliubo save_error_info(fs_info); 144acce952bSliubo 145acce952bSliubo btrfs_handle_error(fs_info); 146acce952bSliubo } 147acce952bSliubo 148e20d96d6SChris Mason static void btrfs_put_super(struct super_block *sb) 149e20d96d6SChris Mason { 150aea52e19SAl Viro (void)close_ctree(btrfs_sb(sb)); 151aea52e19SAl Viro /* FIXME: need to fix VFS to return error? */ 152aea52e19SAl Viro /* AV: return it _where_? ->put_super() can be triggered by any number 153aea52e19SAl Viro * of async events, up to and including delivery of SIGKILL to the 154aea52e19SAl Viro * last process that kept it busy. Or segfault in the aforementioned 155aea52e19SAl Viro * process... Whom would you report that to? 156aea52e19SAl Viro */ 157e20d96d6SChris Mason } 1582e635a27SChris Mason 15995e05289SChris Mason enum { 16073f73415SJosef Bacik Opt_degraded, Opt_subvol, Opt_subvolid, Opt_device, Opt_nodatasum, 161287a0ab9SJosef Bacik Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd, 162287a0ab9SJosef Bacik Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress, 163261507a0SLi Zefan Opt_compress_type, Opt_compress_force, Opt_compress_force_type, 164261507a0SLi Zefan Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard, 16591435650SChris Mason Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed, 1664b9465cbSChris Mason Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, 167af31f5e5SChris Mason Opt_inode_cache, Opt_no_space_cache, Opt_recovery, Opt_err, 16895e05289SChris Mason }; 16995e05289SChris Mason 17095e05289SChris Mason static match_table_t tokens = { 171dfe25020SChris Mason {Opt_degraded, "degraded"}, 17295e05289SChris Mason {Opt_subvol, "subvol=%s"}, 17373f73415SJosef Bacik {Opt_subvolid, "subvolid=%d"}, 17443e570b0SChristoph Hellwig {Opt_device, "device=%s"}, 175b6cda9bcSChris Mason {Opt_nodatasum, "nodatasum"}, 176be20aa9dSChris Mason {Opt_nodatacow, "nodatacow"}, 17721ad10cfSChris Mason {Opt_nobarrier, "nobarrier"}, 1786f568d35SChris Mason {Opt_max_inline, "max_inline=%s"}, 1798f662a76SChris Mason {Opt_alloc_start, "alloc_start=%s"}, 1804543df7eSChris Mason {Opt_thread_pool, "thread_pool=%d"}, 181c8b97818SChris Mason {Opt_compress, "compress"}, 182261507a0SLi Zefan {Opt_compress_type, "compress=%s"}, 183a555f810SChris Mason {Opt_compress_force, "compress-force"}, 184261507a0SLi Zefan {Opt_compress_force_type, "compress-force=%s"}, 185e18e4809SChris Mason {Opt_ssd, "ssd"}, 186451d7585SChris Mason {Opt_ssd_spread, "ssd_spread"}, 1873b30c22fSChris Mason {Opt_nossd, "nossd"}, 18833268eafSJosef Bacik {Opt_noacl, "noacl"}, 1893a5e1404SSage Weil {Opt_notreelog, "notreelog"}, 190dccae999SSage Weil {Opt_flushoncommit, "flushoncommit"}, 19197e728d4SJosef Bacik {Opt_ratio, "metadata_ratio=%d"}, 192e244a0aeSChristoph Hellwig {Opt_discard, "discard"}, 1930af3d00bSJosef Bacik {Opt_space_cache, "space_cache"}, 19488c2ba3bSJosef Bacik {Opt_clear_cache, "clear_cache"}, 1954260f7c7SSage Weil {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, 19691435650SChris Mason {Opt_enospc_debug, "enospc_debug"}, 197e15d0542SXin Zhong {Opt_subvolrootid, "subvolrootid=%d"}, 1984cb5300bSChris Mason {Opt_defrag, "autodefrag"}, 1994b9465cbSChris Mason {Opt_inode_cache, "inode_cache"}, 2008965593eSDavid Sterba {Opt_no_space_cache, "nospace_cache"}, 201af31f5e5SChris Mason {Opt_recovery, "recovery"}, 20233268eafSJosef Bacik {Opt_err, NULL}, 20395e05289SChris Mason }; 20495e05289SChris Mason 205edf24abeSChristoph Hellwig /* 206edf24abeSChristoph Hellwig * Regular mount options parser. Everything that is needed only when 207edf24abeSChristoph Hellwig * reading in a new superblock is parsed here. 208edf24abeSChristoph Hellwig */ 209edf24abeSChristoph Hellwig int btrfs_parse_options(struct btrfs_root *root, char *options) 21095e05289SChris Mason { 211edf24abeSChristoph Hellwig struct btrfs_fs_info *info = root->fs_info; 21295e05289SChris Mason substring_t args[MAX_OPT_ARGS]; 21373bc1876SJosef Bacik char *p, *num, *orig = NULL; 21473bc1876SJosef Bacik u64 cache_gen; 2154543df7eSChris Mason int intarg; 216a7a3f7caSSage Weil int ret = 0; 217261507a0SLi Zefan char *compress_type; 218261507a0SLi Zefan bool compress_force = false; 219b6cda9bcSChris Mason 2206c41761fSDavid Sterba cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy); 22173bc1876SJosef Bacik if (cache_gen) 22273bc1876SJosef Bacik btrfs_set_opt(info->mount_opt, SPACE_CACHE); 22373bc1876SJosef Bacik 22495e05289SChris Mason if (!options) 22573bc1876SJosef Bacik goto out; 22695e05289SChris Mason 227be20aa9dSChris Mason /* 228be20aa9dSChris Mason * strsep changes the string, duplicate it because parse_options 229be20aa9dSChris Mason * gets called twice 230be20aa9dSChris Mason */ 231be20aa9dSChris Mason options = kstrdup(options, GFP_NOFS); 232be20aa9dSChris Mason if (!options) 233be20aa9dSChris Mason return -ENOMEM; 234be20aa9dSChris Mason 235da495eccSJosef Bacik orig = options; 236be20aa9dSChris Mason 23795e05289SChris Mason while ((p = strsep(&options, ",")) != NULL) { 23895e05289SChris Mason int token; 23995e05289SChris Mason if (!*p) 24095e05289SChris Mason continue; 24195e05289SChris Mason 24295e05289SChris Mason token = match_token(p, tokens, args); 24395e05289SChris Mason switch (token) { 244dfe25020SChris Mason case Opt_degraded: 245edf24abeSChristoph Hellwig printk(KERN_INFO "btrfs: allowing degraded mounts\n"); 246dfe25020SChris Mason btrfs_set_opt(info->mount_opt, DEGRADED); 247dfe25020SChris Mason break; 24895e05289SChris Mason case Opt_subvol: 24973f73415SJosef Bacik case Opt_subvolid: 250e15d0542SXin Zhong case Opt_subvolrootid: 25143e570b0SChristoph Hellwig case Opt_device: 252edf24abeSChristoph Hellwig /* 25343e570b0SChristoph Hellwig * These are parsed by btrfs_parse_early_options 254edf24abeSChristoph Hellwig * and can be happily ignored here. 255edf24abeSChristoph Hellwig */ 25695e05289SChris Mason break; 257b6cda9bcSChris Mason case Opt_nodatasum: 258067c28adSChris Mason printk(KERN_INFO "btrfs: setting nodatasum\n"); 259b6cda9bcSChris Mason btrfs_set_opt(info->mount_opt, NODATASUM); 260be20aa9dSChris Mason break; 261be20aa9dSChris Mason case Opt_nodatacow: 262edf24abeSChristoph Hellwig printk(KERN_INFO "btrfs: setting nodatacow\n"); 263be20aa9dSChris Mason btrfs_set_opt(info->mount_opt, NODATACOW); 264be20aa9dSChris Mason btrfs_set_opt(info->mount_opt, NODATASUM); 265b6cda9bcSChris Mason break; 266a555f810SChris Mason case Opt_compress_force: 267261507a0SLi Zefan case Opt_compress_force_type: 268261507a0SLi Zefan compress_force = true; 269261507a0SLi Zefan case Opt_compress: 270261507a0SLi Zefan case Opt_compress_type: 271261507a0SLi Zefan if (token == Opt_compress || 272261507a0SLi Zefan token == Opt_compress_force || 273261507a0SLi Zefan strcmp(args[0].from, "zlib") == 0) { 274261507a0SLi Zefan compress_type = "zlib"; 275261507a0SLi Zefan info->compress_type = BTRFS_COMPRESS_ZLIB; 276a6fa6faeSLi Zefan } else if (strcmp(args[0].from, "lzo") == 0) { 277a6fa6faeSLi Zefan compress_type = "lzo"; 278a6fa6faeSLi Zefan info->compress_type = BTRFS_COMPRESS_LZO; 279261507a0SLi Zefan } else { 280261507a0SLi Zefan ret = -EINVAL; 281261507a0SLi Zefan goto out; 282261507a0SLi Zefan } 283261507a0SLi Zefan 284a555f810SChris Mason btrfs_set_opt(info->mount_opt, COMPRESS); 285261507a0SLi Zefan if (compress_force) { 286261507a0SLi Zefan btrfs_set_opt(info->mount_opt, FORCE_COMPRESS); 287261507a0SLi Zefan pr_info("btrfs: force %s compression\n", 288261507a0SLi Zefan compress_type); 289261507a0SLi Zefan } else 290261507a0SLi Zefan pr_info("btrfs: use %s compression\n", 291261507a0SLi Zefan compress_type); 292a555f810SChris Mason break; 293e18e4809SChris Mason case Opt_ssd: 294edf24abeSChristoph Hellwig printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); 295e18e4809SChris Mason btrfs_set_opt(info->mount_opt, SSD); 296e18e4809SChris Mason break; 297451d7585SChris Mason case Opt_ssd_spread: 298451d7585SChris Mason printk(KERN_INFO "btrfs: use spread ssd " 299451d7585SChris Mason "allocation scheme\n"); 300451d7585SChris Mason btrfs_set_opt(info->mount_opt, SSD); 301451d7585SChris Mason btrfs_set_opt(info->mount_opt, SSD_SPREAD); 302451d7585SChris Mason break; 3033b30c22fSChris Mason case Opt_nossd: 304451d7585SChris Mason printk(KERN_INFO "btrfs: not using ssd allocation " 305451d7585SChris Mason "scheme\n"); 306c289811cSChris Mason btrfs_set_opt(info->mount_opt, NOSSD); 3073b30c22fSChris Mason btrfs_clear_opt(info->mount_opt, SSD); 308451d7585SChris Mason btrfs_clear_opt(info->mount_opt, SSD_SPREAD); 3093b30c22fSChris Mason break; 31021ad10cfSChris Mason case Opt_nobarrier: 311edf24abeSChristoph Hellwig printk(KERN_INFO "btrfs: turning off barriers\n"); 31221ad10cfSChris Mason btrfs_set_opt(info->mount_opt, NOBARRIER); 31321ad10cfSChris Mason break; 3144543df7eSChris Mason case Opt_thread_pool: 3154543df7eSChris Mason intarg = 0; 3164543df7eSChris Mason match_int(&args[0], &intarg); 3174543df7eSChris Mason if (intarg) { 3184543df7eSChris Mason info->thread_pool_size = intarg; 3194543df7eSChris Mason printk(KERN_INFO "btrfs: thread pool %d\n", 3204543df7eSChris Mason info->thread_pool_size); 3214543df7eSChris Mason } 3224543df7eSChris Mason break; 3236f568d35SChris Mason case Opt_max_inline: 324edf24abeSChristoph Hellwig num = match_strdup(&args[0]); 3256f568d35SChris Mason if (num) { 32691748467SAkinobu Mita info->max_inline = memparse(num, NULL); 3276f568d35SChris Mason kfree(num); 3286f568d35SChris Mason 32915ada040SChris Mason if (info->max_inline) { 3306f568d35SChris Mason info->max_inline = max_t(u64, 33115ada040SChris Mason info->max_inline, 33215ada040SChris Mason root->sectorsize); 33315ada040SChris Mason } 334edf24abeSChristoph Hellwig printk(KERN_INFO "btrfs: max_inline at %llu\n", 33521380931SJoel Becker (unsigned long long)info->max_inline); 3366f568d35SChris Mason } 3376f568d35SChris Mason break; 3388f662a76SChris Mason case Opt_alloc_start: 339edf24abeSChristoph Hellwig num = match_strdup(&args[0]); 3408f662a76SChris Mason if (num) { 34191748467SAkinobu Mita info->alloc_start = memparse(num, NULL); 3428f662a76SChris Mason kfree(num); 343edf24abeSChristoph Hellwig printk(KERN_INFO 344edf24abeSChristoph Hellwig "btrfs: allocations start at %llu\n", 34521380931SJoel Becker (unsigned long long)info->alloc_start); 3468f662a76SChris Mason } 3478f662a76SChris Mason break; 34833268eafSJosef Bacik case Opt_noacl: 34933268eafSJosef Bacik root->fs_info->sb->s_flags &= ~MS_POSIXACL; 35033268eafSJosef Bacik break; 3513a5e1404SSage Weil case Opt_notreelog: 3523a5e1404SSage Weil printk(KERN_INFO "btrfs: disabling tree log\n"); 3533a5e1404SSage Weil btrfs_set_opt(info->mount_opt, NOTREELOG); 3543a5e1404SSage Weil break; 355dccae999SSage Weil case Opt_flushoncommit: 356dccae999SSage Weil printk(KERN_INFO "btrfs: turning on flush-on-commit\n"); 357dccae999SSage Weil btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT); 358dccae999SSage Weil break; 35997e728d4SJosef Bacik case Opt_ratio: 36097e728d4SJosef Bacik intarg = 0; 36197e728d4SJosef Bacik match_int(&args[0], &intarg); 36297e728d4SJosef Bacik if (intarg) { 36397e728d4SJosef Bacik info->metadata_ratio = intarg; 36497e728d4SJosef Bacik printk(KERN_INFO "btrfs: metadata ratio %d\n", 36597e728d4SJosef Bacik info->metadata_ratio); 36697e728d4SJosef Bacik } 36797e728d4SJosef Bacik break; 368e244a0aeSChristoph Hellwig case Opt_discard: 369e244a0aeSChristoph Hellwig btrfs_set_opt(info->mount_opt, DISCARD); 370e244a0aeSChristoph Hellwig break; 3710af3d00bSJosef Bacik case Opt_space_cache: 3720af3d00bSJosef Bacik btrfs_set_opt(info->mount_opt, SPACE_CACHE); 3730de90876SJosef Bacik break; 37473bc1876SJosef Bacik case Opt_no_space_cache: 37573bc1876SJosef Bacik printk(KERN_INFO "btrfs: disabling disk space caching\n"); 37673bc1876SJosef Bacik btrfs_clear_opt(info->mount_opt, SPACE_CACHE); 37773bc1876SJosef Bacik break; 3784b9465cbSChris Mason case Opt_inode_cache: 3794b9465cbSChris Mason printk(KERN_INFO "btrfs: enabling inode map caching\n"); 3804b9465cbSChris Mason btrfs_set_opt(info->mount_opt, INODE_MAP_CACHE); 3814b9465cbSChris Mason break; 38288c2ba3bSJosef Bacik case Opt_clear_cache: 38388c2ba3bSJosef Bacik printk(KERN_INFO "btrfs: force clearing of disk cache\n"); 38488c2ba3bSJosef Bacik btrfs_set_opt(info->mount_opt, CLEAR_CACHE); 3850af3d00bSJosef Bacik break; 3864260f7c7SSage Weil case Opt_user_subvol_rm_allowed: 3874260f7c7SSage Weil btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED); 3884260f7c7SSage Weil break; 38991435650SChris Mason case Opt_enospc_debug: 39091435650SChris Mason btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG); 39191435650SChris Mason break; 3924cb5300bSChris Mason case Opt_defrag: 3934cb5300bSChris Mason printk(KERN_INFO "btrfs: enabling auto defrag"); 3944cb5300bSChris Mason btrfs_set_opt(info->mount_opt, AUTO_DEFRAG); 3954cb5300bSChris Mason break; 396af31f5e5SChris Mason case Opt_recovery: 397af31f5e5SChris Mason printk(KERN_INFO "btrfs: enabling auto recovery"); 398af31f5e5SChris Mason btrfs_set_opt(info->mount_opt, RECOVERY); 399af31f5e5SChris Mason break; 400a7a3f7caSSage Weil case Opt_err: 401a7a3f7caSSage Weil printk(KERN_INFO "btrfs: unrecognized mount option " 402a7a3f7caSSage Weil "'%s'\n", p); 403a7a3f7caSSage Weil ret = -EINVAL; 404a7a3f7caSSage Weil goto out; 40595e05289SChris Mason default: 406be20aa9dSChris Mason break; 40795e05289SChris Mason } 40895e05289SChris Mason } 409a7a3f7caSSage Weil out: 41073bc1876SJosef Bacik if (!ret && btrfs_test_opt(root, SPACE_CACHE)) 41173bc1876SJosef Bacik printk(KERN_INFO "btrfs: disk space caching is enabled\n"); 412da495eccSJosef Bacik kfree(orig); 413a7a3f7caSSage Weil return ret; 414edf24abeSChristoph Hellwig } 415edf24abeSChristoph Hellwig 416edf24abeSChristoph Hellwig /* 417edf24abeSChristoph Hellwig * Parse mount options that are required early in the mount process. 418edf24abeSChristoph Hellwig * 419edf24abeSChristoph Hellwig * All other options will be parsed on much later in the mount process and 420edf24abeSChristoph Hellwig * only when we need to allocate a new super block. 421edf24abeSChristoph Hellwig */ 42297288f2cSChristoph Hellwig static int btrfs_parse_early_options(const char *options, fmode_t flags, 42373f73415SJosef Bacik void *holder, char **subvol_name, u64 *subvol_objectid, 424e15d0542SXin Zhong u64 *subvol_rootid, struct btrfs_fs_devices **fs_devices) 425edf24abeSChristoph Hellwig { 426edf24abeSChristoph Hellwig substring_t args[MAX_OPT_ARGS]; 42783c8c9bdSJeff Liu char *device_name, *opts, *orig, *p; 428edf24abeSChristoph Hellwig int error = 0; 42973f73415SJosef Bacik int intarg; 430edf24abeSChristoph Hellwig 431edf24abeSChristoph Hellwig if (!options) 432830c4adbSJosef Bacik return 0; 433edf24abeSChristoph Hellwig 434edf24abeSChristoph Hellwig /* 435edf24abeSChristoph Hellwig * strsep changes the string, duplicate it because parse_options 436edf24abeSChristoph Hellwig * gets called twice 437edf24abeSChristoph Hellwig */ 438edf24abeSChristoph Hellwig opts = kstrdup(options, GFP_KERNEL); 439edf24abeSChristoph Hellwig if (!opts) 440edf24abeSChristoph Hellwig return -ENOMEM; 4413f3d0bc0STero Roponen orig = opts; 442edf24abeSChristoph Hellwig 443edf24abeSChristoph Hellwig while ((p = strsep(&opts, ",")) != NULL) { 444edf24abeSChristoph Hellwig int token; 445edf24abeSChristoph Hellwig if (!*p) 446edf24abeSChristoph Hellwig continue; 447edf24abeSChristoph Hellwig 448edf24abeSChristoph Hellwig token = match_token(p, tokens, args); 449edf24abeSChristoph Hellwig switch (token) { 450edf24abeSChristoph Hellwig case Opt_subvol: 451a90e8b6fSIlya Dryomov kfree(*subvol_name); 452edf24abeSChristoph Hellwig *subvol_name = match_strdup(&args[0]); 453edf24abeSChristoph Hellwig break; 45473f73415SJosef Bacik case Opt_subvolid: 45573f73415SJosef Bacik intarg = 0; 4564849f01dSJosef Bacik error = match_int(&args[0], &intarg); 4574849f01dSJosef Bacik if (!error) { 4584849f01dSJosef Bacik /* we want the original fs_tree */ 4594849f01dSJosef Bacik if (!intarg) 4604849f01dSJosef Bacik *subvol_objectid = 4614849f01dSJosef Bacik BTRFS_FS_TREE_OBJECTID; 4624849f01dSJosef Bacik else 46373f73415SJosef Bacik *subvol_objectid = intarg; 4644849f01dSJosef Bacik } 46573f73415SJosef Bacik break; 466e15d0542SXin Zhong case Opt_subvolrootid: 467e15d0542SXin Zhong intarg = 0; 468e15d0542SXin Zhong error = match_int(&args[0], &intarg); 469e15d0542SXin Zhong if (!error) { 470e15d0542SXin Zhong /* we want the original fs_tree */ 471e15d0542SXin Zhong if (!intarg) 472e15d0542SXin Zhong *subvol_rootid = 473e15d0542SXin Zhong BTRFS_FS_TREE_OBJECTID; 474e15d0542SXin Zhong else 475e15d0542SXin Zhong *subvol_rootid = intarg; 476e15d0542SXin Zhong } 477e15d0542SXin Zhong break; 47843e570b0SChristoph Hellwig case Opt_device: 47983c8c9bdSJeff Liu device_name = match_strdup(&args[0]); 48083c8c9bdSJeff Liu if (!device_name) { 48183c8c9bdSJeff Liu error = -ENOMEM; 48283c8c9bdSJeff Liu goto out; 48383c8c9bdSJeff Liu } 48483c8c9bdSJeff Liu error = btrfs_scan_one_device(device_name, 48543e570b0SChristoph Hellwig flags, holder, fs_devices); 48683c8c9bdSJeff Liu kfree(device_name); 48743e570b0SChristoph Hellwig if (error) 488830c4adbSJosef Bacik goto out; 48943e570b0SChristoph Hellwig break; 490edf24abeSChristoph Hellwig default: 491edf24abeSChristoph Hellwig break; 492edf24abeSChristoph Hellwig } 493edf24abeSChristoph Hellwig } 494edf24abeSChristoph Hellwig 495edf24abeSChristoph Hellwig out: 496830c4adbSJosef Bacik kfree(orig); 497edf24abeSChristoph Hellwig return error; 49895e05289SChris Mason } 49995e05289SChris Mason 50073f73415SJosef Bacik static struct dentry *get_default_root(struct super_block *sb, 50173f73415SJosef Bacik u64 subvol_objectid) 50273f73415SJosef Bacik { 50373f73415SJosef Bacik struct btrfs_root *root = sb->s_fs_info; 50473f73415SJosef Bacik struct btrfs_root *new_root; 50573f73415SJosef Bacik struct btrfs_dir_item *di; 50673f73415SJosef Bacik struct btrfs_path *path; 50773f73415SJosef Bacik struct btrfs_key location; 50873f73415SJosef Bacik struct inode *inode; 50973f73415SJosef Bacik u64 dir_id; 51073f73415SJosef Bacik int new = 0; 51173f73415SJosef Bacik 51273f73415SJosef Bacik /* 51373f73415SJosef Bacik * We have a specific subvol we want to mount, just setup location and 51473f73415SJosef Bacik * go look up the root. 51573f73415SJosef Bacik */ 51673f73415SJosef Bacik if (subvol_objectid) { 51773f73415SJosef Bacik location.objectid = subvol_objectid; 51873f73415SJosef Bacik location.type = BTRFS_ROOT_ITEM_KEY; 51973f73415SJosef Bacik location.offset = (u64)-1; 52073f73415SJosef Bacik goto find_root; 52173f73415SJosef Bacik } 52273f73415SJosef Bacik 52373f73415SJosef Bacik path = btrfs_alloc_path(); 52473f73415SJosef Bacik if (!path) 52573f73415SJosef Bacik return ERR_PTR(-ENOMEM); 52673f73415SJosef Bacik path->leave_spinning = 1; 52773f73415SJosef Bacik 52873f73415SJosef Bacik /* 52973f73415SJosef Bacik * Find the "default" dir item which points to the root item that we 53073f73415SJosef Bacik * will mount by default if we haven't been given a specific subvolume 53173f73415SJosef Bacik * to mount. 53273f73415SJosef Bacik */ 5336c41761fSDavid Sterba dir_id = btrfs_super_root_dir(root->fs_info->super_copy); 53473f73415SJosef Bacik di = btrfs_lookup_dir_item(NULL, root, path, dir_id, "default", 7, 0); 535b0839166SJulia Lawall if (IS_ERR(di)) { 536b0839166SJulia Lawall btrfs_free_path(path); 537fb4f6f91SDan Carpenter return ERR_CAST(di); 538b0839166SJulia Lawall } 53973f73415SJosef Bacik if (!di) { 54073f73415SJosef Bacik /* 54173f73415SJosef Bacik * Ok the default dir item isn't there. This is weird since 54273f73415SJosef Bacik * it's always been there, but don't freak out, just try and 54373f73415SJosef Bacik * mount to root most subvolume. 54473f73415SJosef Bacik */ 54573f73415SJosef Bacik btrfs_free_path(path); 54673f73415SJosef Bacik dir_id = BTRFS_FIRST_FREE_OBJECTID; 54773f73415SJosef Bacik new_root = root->fs_info->fs_root; 54873f73415SJosef Bacik goto setup_root; 54973f73415SJosef Bacik } 55073f73415SJosef Bacik 55173f73415SJosef Bacik btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); 55273f73415SJosef Bacik btrfs_free_path(path); 55373f73415SJosef Bacik 55473f73415SJosef Bacik find_root: 55573f73415SJosef Bacik new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); 55673f73415SJosef Bacik if (IS_ERR(new_root)) 557d0b678cbSJulia Lawall return ERR_CAST(new_root); 55873f73415SJosef Bacik 55973f73415SJosef Bacik if (btrfs_root_refs(&new_root->root_item) == 0) 56073f73415SJosef Bacik return ERR_PTR(-ENOENT); 56173f73415SJosef Bacik 56273f73415SJosef Bacik dir_id = btrfs_root_dirid(&new_root->root_item); 56373f73415SJosef Bacik setup_root: 56473f73415SJosef Bacik location.objectid = dir_id; 56573f73415SJosef Bacik location.type = BTRFS_INODE_ITEM_KEY; 56673f73415SJosef Bacik location.offset = 0; 56773f73415SJosef Bacik 56873f73415SJosef Bacik inode = btrfs_iget(sb, &location, new_root, &new); 5694cbd1149SDan Carpenter if (IS_ERR(inode)) 5704cbd1149SDan Carpenter return ERR_CAST(inode); 57173f73415SJosef Bacik 57273f73415SJosef Bacik /* 57373f73415SJosef Bacik * If we're just mounting the root most subvol put the inode and return 57473f73415SJosef Bacik * a reference to the dentry. We will have already gotten a reference 57573f73415SJosef Bacik * to the inode in btrfs_fill_super so we're good to go. 57673f73415SJosef Bacik */ 57773f73415SJosef Bacik if (!new && sb->s_root->d_inode == inode) { 57873f73415SJosef Bacik iput(inode); 57973f73415SJosef Bacik return dget(sb->s_root); 58073f73415SJosef Bacik } 58173f73415SJosef Bacik 582ba5b8958SJosef Bacik return d_obtain_alias(inode); 58373f73415SJosef Bacik } 58473f73415SJosef Bacik 5858a4b83ccSChris Mason static int btrfs_fill_super(struct super_block *sb, 5868a4b83ccSChris Mason struct btrfs_fs_devices *fs_devices, 5878a4b83ccSChris Mason void *data, int silent) 5882e635a27SChris Mason { 5892e635a27SChris Mason struct inode *inode; 590e20d96d6SChris Mason struct dentry *root_dentry; 59129db78aaSAl Viro struct btrfs_root *tree_root = sb->s_fs_info; 59229db78aaSAl Viro struct btrfs_fs_info *fs_info = tree_root->fs_info; 5935d4f98a2SYan Zheng struct btrfs_key key; 59439279cc3SChris Mason int err; 5952e635a27SChris Mason 5962e635a27SChris Mason sb->s_maxbytes = MAX_LFS_FILESIZE; 5972e635a27SChris Mason sb->s_magic = BTRFS_SUPER_MAGIC; 598e20d96d6SChris Mason sb->s_op = &btrfs_super_ops; 599af53d29aSAl Viro sb->s_d_op = &btrfs_dentry_operations; 600be6e8dc0SBalaji Rao sb->s_export_op = &btrfs_export_ops; 6015103e947SJosef Bacik sb->s_xattr = btrfs_xattr_handlers; 6022e635a27SChris Mason sb->s_time_gran = 1; 6030eda294dSChris Mason #ifdef CONFIG_BTRFS_FS_POSIX_ACL 60433268eafSJosef Bacik sb->s_flags |= MS_POSIXACL; 60549cf6f45SChris Ball #endif 606e20d96d6SChris Mason 607ad2b2c80SAl Viro err = open_ctree(sb, fs_devices, (char *)data); 608ad2b2c80SAl Viro if (err) { 609e20d96d6SChris Mason printk("btrfs: open_ctree failed\n"); 610ad2b2c80SAl Viro return err; 611e20d96d6SChris Mason } 612b888db2bSChris Mason 6135d4f98a2SYan Zheng key.objectid = BTRFS_FIRST_FREE_OBJECTID; 6145d4f98a2SYan Zheng key.type = BTRFS_INODE_ITEM_KEY; 6155d4f98a2SYan Zheng key.offset = 0; 61698c7089cSAl Viro inode = btrfs_iget(sb, &key, fs_info->fs_root, NULL); 6175d4f98a2SYan Zheng if (IS_ERR(inode)) { 6185d4f98a2SYan Zheng err = PTR_ERR(inode); 61939279cc3SChris Mason goto fail_close; 62039279cc3SChris Mason } 6212e635a27SChris Mason 622e20d96d6SChris Mason root_dentry = d_alloc_root(inode); 623e20d96d6SChris Mason if (!root_dentry) { 6242e635a27SChris Mason iput(inode); 62539279cc3SChris Mason err = -ENOMEM; 62639279cc3SChris Mason goto fail_close; 6272e635a27SChris Mason } 62858176a96SJosef Bacik 629e20d96d6SChris Mason sb->s_root = root_dentry; 6306885f308SChris Mason 6316885f308SChris Mason save_mount_options(sb, data); 63290a887c9SDan Magenheimer cleancache_init_fs(sb); 633*59553edfSAl Viro sb->s_flags |= MS_ACTIVE; 6342e635a27SChris Mason return 0; 6352e635a27SChris Mason 63639279cc3SChris Mason fail_close: 63739279cc3SChris Mason close_ctree(tree_root); 638d5719762SChris Mason return err; 639d5719762SChris Mason } 640d5719762SChris Mason 6416bf13c0cSSage Weil int btrfs_sync_fs(struct super_block *sb, int wait) 642d5719762SChris Mason { 643d5719762SChris Mason struct btrfs_trans_handle *trans; 644dccae999SSage Weil struct btrfs_root *root = btrfs_sb(sb); 645d5719762SChris Mason int ret; 646df2ce34cSChris Mason 6471abe9b8aSliubo trace_btrfs_sync_fs(wait); 6481abe9b8aSliubo 649d561c025SChris Mason if (!wait) { 6507cfcc17eSChris Mason filemap_flush(root->fs_info->btree_inode->i_mapping); 651df2ce34cSChris Mason return 0; 652d561c025SChris Mason } 653771ed689SChris Mason 65424bbcf04SYan, Zheng btrfs_start_delalloc_inodes(root, 0); 65524bbcf04SYan, Zheng btrfs_wait_ordered_extents(root, 0, 0); 656771ed689SChris Mason 657a22285a6SYan, Zheng trans = btrfs_start_transaction(root, 0); 65898d5dc13STsutomu Itoh if (IS_ERR(trans)) 65998d5dc13STsutomu Itoh return PTR_ERR(trans); 660d5719762SChris Mason ret = btrfs_commit_transaction(trans, root); 66154aa1f4dSChris Mason return ret; 662d5719762SChris Mason } 663d5719762SChris Mason 66434c80b1dSAl Viro static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) 665a9572a15SEric Paris { 66634c80b1dSAl Viro struct btrfs_root *root = btrfs_sb(dentry->d_sb); 667a9572a15SEric Paris struct btrfs_fs_info *info = root->fs_info; 668200da64eSTsutomu Itoh char *compress_type; 669a9572a15SEric Paris 670a9572a15SEric Paris if (btrfs_test_opt(root, DEGRADED)) 671a9572a15SEric Paris seq_puts(seq, ",degraded"); 672a9572a15SEric Paris if (btrfs_test_opt(root, NODATASUM)) 673a9572a15SEric Paris seq_puts(seq, ",nodatasum"); 674a9572a15SEric Paris if (btrfs_test_opt(root, NODATACOW)) 675a9572a15SEric Paris seq_puts(seq, ",nodatacow"); 676a9572a15SEric Paris if (btrfs_test_opt(root, NOBARRIER)) 677a9572a15SEric Paris seq_puts(seq, ",nobarrier"); 678a9572a15SEric Paris if (info->max_inline != 8192 * 1024) 67921380931SJoel Becker seq_printf(seq, ",max_inline=%llu", 68021380931SJoel Becker (unsigned long long)info->max_inline); 681a9572a15SEric Paris if (info->alloc_start != 0) 68221380931SJoel Becker seq_printf(seq, ",alloc_start=%llu", 68321380931SJoel Becker (unsigned long long)info->alloc_start); 684a9572a15SEric Paris if (info->thread_pool_size != min_t(unsigned long, 685a9572a15SEric Paris num_online_cpus() + 2, 8)) 686a9572a15SEric Paris seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); 687200da64eSTsutomu Itoh if (btrfs_test_opt(root, COMPRESS)) { 688200da64eSTsutomu Itoh if (info->compress_type == BTRFS_COMPRESS_ZLIB) 689200da64eSTsutomu Itoh compress_type = "zlib"; 690200da64eSTsutomu Itoh else 691200da64eSTsutomu Itoh compress_type = "lzo"; 692200da64eSTsutomu Itoh if (btrfs_test_opt(root, FORCE_COMPRESS)) 693200da64eSTsutomu Itoh seq_printf(seq, ",compress-force=%s", compress_type); 694200da64eSTsutomu Itoh else 695200da64eSTsutomu Itoh seq_printf(seq, ",compress=%s", compress_type); 696200da64eSTsutomu Itoh } 697c289811cSChris Mason if (btrfs_test_opt(root, NOSSD)) 698c289811cSChris Mason seq_puts(seq, ",nossd"); 699451d7585SChris Mason if (btrfs_test_opt(root, SSD_SPREAD)) 700451d7585SChris Mason seq_puts(seq, ",ssd_spread"); 701451d7585SChris Mason else if (btrfs_test_opt(root, SSD)) 702a9572a15SEric Paris seq_puts(seq, ",ssd"); 7033a5e1404SSage Weil if (btrfs_test_opt(root, NOTREELOG)) 7046b65c5c6SSage Weil seq_puts(seq, ",notreelog"); 705dccae999SSage Weil if (btrfs_test_opt(root, FLUSHONCOMMIT)) 7066b65c5c6SSage Weil seq_puts(seq, ",flushoncommit"); 70720a5239aSMatthew Wilcox if (btrfs_test_opt(root, DISCARD)) 70820a5239aSMatthew Wilcox seq_puts(seq, ",discard"); 709a9572a15SEric Paris if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) 710a9572a15SEric Paris seq_puts(seq, ",noacl"); 711200da64eSTsutomu Itoh if (btrfs_test_opt(root, SPACE_CACHE)) 712200da64eSTsutomu Itoh seq_puts(seq, ",space_cache"); 71373bc1876SJosef Bacik else 7148965593eSDavid Sterba seq_puts(seq, ",nospace_cache"); 715200da64eSTsutomu Itoh if (btrfs_test_opt(root, CLEAR_CACHE)) 716200da64eSTsutomu Itoh seq_puts(seq, ",clear_cache"); 717200da64eSTsutomu Itoh if (btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) 718200da64eSTsutomu Itoh seq_puts(seq, ",user_subvol_rm_allowed"); 7190942caa3SDavid Sterba if (btrfs_test_opt(root, ENOSPC_DEBUG)) 7200942caa3SDavid Sterba seq_puts(seq, ",enospc_debug"); 7210942caa3SDavid Sterba if (btrfs_test_opt(root, AUTO_DEFRAG)) 7220942caa3SDavid Sterba seq_puts(seq, ",autodefrag"); 7230942caa3SDavid Sterba if (btrfs_test_opt(root, INODE_MAP_CACHE)) 7240942caa3SDavid Sterba seq_puts(seq, ",inode_cache"); 725a9572a15SEric Paris return 0; 726a9572a15SEric Paris } 727a9572a15SEric Paris 728a061fc8dSChris Mason static int btrfs_test_super(struct super_block *s, void *data) 7292e635a27SChris Mason { 730450ba0eaSJosef Bacik struct btrfs_root *test_root = data; 731a061fc8dSChris Mason struct btrfs_root *root = btrfs_sb(s); 7324b82d6e4SYan 733450ba0eaSJosef Bacik return root->fs_info->fs_devices == test_root->fs_info->fs_devices; 7344b82d6e4SYan } 7354b82d6e4SYan 736450ba0eaSJosef Bacik static int btrfs_set_super(struct super_block *s, void *data) 737450ba0eaSJosef Bacik { 7386de1d09dSAl Viro int err = set_anon_super(s, data); 7396de1d09dSAl Viro if (!err) 740450ba0eaSJosef Bacik s->s_fs_info = data; 7416de1d09dSAl Viro return err; 742450ba0eaSJosef Bacik } 743450ba0eaSJosef Bacik 744830c4adbSJosef Bacik /* 745f9d9ef62SDavid Sterba * subvolumes are identified by ino 256 746f9d9ef62SDavid Sterba */ 747f9d9ef62SDavid Sterba static inline int is_subvolume_inode(struct inode *inode) 748f9d9ef62SDavid Sterba { 749f9d9ef62SDavid Sterba if (inode && inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) 750f9d9ef62SDavid Sterba return 1; 751f9d9ef62SDavid Sterba return 0; 752f9d9ef62SDavid Sterba } 753f9d9ef62SDavid Sterba 754f9d9ef62SDavid Sterba /* 755830c4adbSJosef Bacik * This will strip out the subvol=%s argument for an argument string and add 756830c4adbSJosef Bacik * subvolid=0 to make sure we get the actual tree root for path walking to the 757830c4adbSJosef Bacik * subvol we want. 758830c4adbSJosef Bacik */ 759830c4adbSJosef Bacik static char *setup_root_args(char *args) 760830c4adbSJosef Bacik { 761830c4adbSJosef Bacik unsigned copied = 0; 762830c4adbSJosef Bacik unsigned len = strlen(args) + 2; 763830c4adbSJosef Bacik char *pos; 764830c4adbSJosef Bacik char *ret; 765830c4adbSJosef Bacik 766830c4adbSJosef Bacik /* 767830c4adbSJosef Bacik * We need the same args as before, but minus 768830c4adbSJosef Bacik * 769830c4adbSJosef Bacik * subvol=a 770830c4adbSJosef Bacik * 771830c4adbSJosef Bacik * and add 772830c4adbSJosef Bacik * 773830c4adbSJosef Bacik * subvolid=0 774830c4adbSJosef Bacik * 775830c4adbSJosef Bacik * which is a difference of 2 characters, so we allocate strlen(args) + 776830c4adbSJosef Bacik * 2 characters. 777830c4adbSJosef Bacik */ 778830c4adbSJosef Bacik ret = kzalloc(len * sizeof(char), GFP_NOFS); 779830c4adbSJosef Bacik if (!ret) 780830c4adbSJosef Bacik return NULL; 781830c4adbSJosef Bacik pos = strstr(args, "subvol="); 782830c4adbSJosef Bacik 783830c4adbSJosef Bacik /* This shouldn't happen, but just in case.. */ 784830c4adbSJosef Bacik if (!pos) { 785830c4adbSJosef Bacik kfree(ret); 786830c4adbSJosef Bacik return NULL; 787830c4adbSJosef Bacik } 788830c4adbSJosef Bacik 789830c4adbSJosef Bacik /* 790830c4adbSJosef Bacik * The subvol=<> arg is not at the front of the string, copy everybody 791830c4adbSJosef Bacik * up to that into ret. 792830c4adbSJosef Bacik */ 793830c4adbSJosef Bacik if (pos != args) { 794830c4adbSJosef Bacik *pos = '\0'; 795830c4adbSJosef Bacik strcpy(ret, args); 796830c4adbSJosef Bacik copied += strlen(args); 797830c4adbSJosef Bacik pos++; 798830c4adbSJosef Bacik } 799830c4adbSJosef Bacik 800830c4adbSJosef Bacik strncpy(ret + copied, "subvolid=0", len - copied); 801830c4adbSJosef Bacik 802830c4adbSJosef Bacik /* Length of subvolid=0 */ 803830c4adbSJosef Bacik copied += 10; 804830c4adbSJosef Bacik 805830c4adbSJosef Bacik /* 806830c4adbSJosef Bacik * If there is no , after the subvol= option then we know there's no 807830c4adbSJosef Bacik * other options and we can just return. 808830c4adbSJosef Bacik */ 809830c4adbSJosef Bacik pos = strchr(pos, ','); 810830c4adbSJosef Bacik if (!pos) 811830c4adbSJosef Bacik return ret; 812830c4adbSJosef Bacik 813830c4adbSJosef Bacik /* Copy the rest of the arguments into our buffer */ 814830c4adbSJosef Bacik strncpy(ret + copied, pos, len - copied); 815830c4adbSJosef Bacik copied += strlen(pos); 816830c4adbSJosef Bacik 817830c4adbSJosef Bacik return ret; 818830c4adbSJosef Bacik } 819830c4adbSJosef Bacik 820830c4adbSJosef Bacik static struct dentry *mount_subvol(const char *subvol_name, int flags, 821830c4adbSJosef Bacik const char *device_name, char *data) 822830c4adbSJosef Bacik { 823830c4adbSJosef Bacik struct dentry *root; 824830c4adbSJosef Bacik struct vfsmount *mnt; 825830c4adbSJosef Bacik char *newargs; 826830c4adbSJosef Bacik 827830c4adbSJosef Bacik newargs = setup_root_args(data); 828830c4adbSJosef Bacik if (!newargs) 829830c4adbSJosef Bacik return ERR_PTR(-ENOMEM); 830830c4adbSJosef Bacik mnt = vfs_kern_mount(&btrfs_fs_type, flags, device_name, 831830c4adbSJosef Bacik newargs); 832830c4adbSJosef Bacik kfree(newargs); 833830c4adbSJosef Bacik if (IS_ERR(mnt)) 834830c4adbSJosef Bacik return ERR_CAST(mnt); 835830c4adbSJosef Bacik 836ea441d11SAl Viro root = mount_subtree(mnt, subvol_name); 837830c4adbSJosef Bacik 838ea441d11SAl Viro if (!IS_ERR(root) && !is_subvolume_inode(root->d_inode)) { 839ea441d11SAl Viro struct super_block *s = root->d_sb; 840ea441d11SAl Viro dput(root); 841ea441d11SAl Viro root = ERR_PTR(-EINVAL); 842ea441d11SAl Viro deactivate_locked_super(s); 843f9d9ef62SDavid Sterba printk(KERN_ERR "btrfs: '%s' is not a valid subvolume\n", 844f9d9ef62SDavid Sterba subvol_name); 845f9d9ef62SDavid Sterba } 846f9d9ef62SDavid Sterba 847830c4adbSJosef Bacik return root; 848830c4adbSJosef Bacik } 849450ba0eaSJosef Bacik 850edf24abeSChristoph Hellwig /* 851edf24abeSChristoph Hellwig * Find a superblock for the given device / mount point. 852edf24abeSChristoph Hellwig * 853edf24abeSChristoph Hellwig * Note: This is based on get_sb_bdev from fs/super.c with a few additions 854edf24abeSChristoph Hellwig * for multiple device setup. Make sure to keep it in sync. 855edf24abeSChristoph Hellwig */ 856061dbc6bSAl Viro static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, 857306e16ceSDavid Sterba const char *device_name, void *data) 8584b82d6e4SYan { 8594b82d6e4SYan struct block_device *bdev = NULL; 8604b82d6e4SYan struct super_block *s; 8614b82d6e4SYan struct dentry *root; 8628a4b83ccSChris Mason struct btrfs_fs_devices *fs_devices = NULL; 863450ba0eaSJosef Bacik struct btrfs_fs_info *fs_info = NULL; 86497288f2cSChristoph Hellwig fmode_t mode = FMODE_READ; 86573f73415SJosef Bacik char *subvol_name = NULL; 86673f73415SJosef Bacik u64 subvol_objectid = 0; 867e15d0542SXin Zhong u64 subvol_rootid = 0; 8684b82d6e4SYan int error = 0; 8694b82d6e4SYan 87097288f2cSChristoph Hellwig if (!(flags & MS_RDONLY)) 87197288f2cSChristoph Hellwig mode |= FMODE_WRITE; 87297288f2cSChristoph Hellwig 87397288f2cSChristoph Hellwig error = btrfs_parse_early_options(data, mode, fs_type, 87473f73415SJosef Bacik &subvol_name, &subvol_objectid, 875e15d0542SXin Zhong &subvol_rootid, &fs_devices); 876f23c8af8SIlya Dryomov if (error) { 877f23c8af8SIlya Dryomov kfree(subvol_name); 878061dbc6bSAl Viro return ERR_PTR(error); 879f23c8af8SIlya Dryomov } 880edf24abeSChristoph Hellwig 881830c4adbSJosef Bacik if (subvol_name) { 882830c4adbSJosef Bacik root = mount_subvol(subvol_name, flags, device_name, data); 883830c4adbSJosef Bacik kfree(subvol_name); 884830c4adbSJosef Bacik return root; 885830c4adbSJosef Bacik } 886830c4adbSJosef Bacik 887306e16ceSDavid Sterba error = btrfs_scan_one_device(device_name, mode, fs_type, &fs_devices); 8888a4b83ccSChris Mason if (error) 889830c4adbSJosef Bacik return ERR_PTR(error); 8904b82d6e4SYan 891450ba0eaSJosef Bacik /* 892450ba0eaSJosef Bacik * Setup a dummy root and fs_info for test/set super. This is because 893450ba0eaSJosef Bacik * we don't actually fill this stuff out until open_ctree, but we need 894450ba0eaSJosef Bacik * it for searching for existing supers, so this lets us do that and 895450ba0eaSJosef Bacik * then open_ctree will properly initialize everything later. 896450ba0eaSJosef Bacik */ 897450ba0eaSJosef Bacik fs_info = kzalloc(sizeof(struct btrfs_fs_info), GFP_NOFS); 89804d21a24SIlya Dryomov if (!fs_info) 89904d21a24SIlya Dryomov return ERR_PTR(-ENOMEM); 90004d21a24SIlya Dryomov 9016f07e42eSAl Viro fs_info->tree_root = btrfs_alloc_root(fs_info); 90204d21a24SIlya Dryomov if (!fs_info->tree_root) { 90345ea6095Sslyich@gmail.com error = -ENOMEM; 90404d21a24SIlya Dryomov goto error_fs_info; 90545ea6095Sslyich@gmail.com } 906450ba0eaSJosef Bacik fs_info->fs_devices = fs_devices; 907450ba0eaSJosef Bacik 9086c41761fSDavid Sterba fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_NOFS); 9096c41761fSDavid Sterba fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_NOFS); 9106c41761fSDavid Sterba if (!fs_info->super_copy || !fs_info->super_for_commit) { 9116c41761fSDavid Sterba error = -ENOMEM; 91204d21a24SIlya Dryomov goto error_fs_info; 91304d21a24SIlya Dryomov } 91404d21a24SIlya Dryomov 91504d21a24SIlya Dryomov error = btrfs_open_devices(fs_devices, mode, fs_type); 91604d21a24SIlya Dryomov if (error) 91704d21a24SIlya Dryomov goto error_fs_info; 91804d21a24SIlya Dryomov 91904d21a24SIlya Dryomov if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { 92004d21a24SIlya Dryomov error = -EACCES; 9216c41761fSDavid Sterba goto error_close_devices; 9226c41761fSDavid Sterba } 9236c41761fSDavid Sterba 924dfe25020SChris Mason bdev = fs_devices->latest_bdev; 92504d21a24SIlya Dryomov s = sget(fs_type, btrfs_test_super, btrfs_set_super, 92604d21a24SIlya Dryomov fs_info->tree_root); 927830c4adbSJosef Bacik if (IS_ERR(s)) { 928830c4adbSJosef Bacik error = PTR_ERR(s); 929830c4adbSJosef Bacik goto error_close_devices; 930830c4adbSJosef Bacik } 9314b82d6e4SYan 9324b82d6e4SYan if (s->s_root) { 9332b82032cSYan Zheng btrfs_close_devices(fs_devices); 9346c41761fSDavid Sterba free_fs_info(fs_info); 935*59553edfSAl Viro if ((flags ^ s->s_flags) & MS_RDONLY) 936*59553edfSAl Viro error = -EBUSY; 9374b82d6e4SYan } else { 9384b82d6e4SYan char b[BDEVNAME_SIZE]; 9394b82d6e4SYan 9409e1f1de0SAl Viro s->s_flags = flags | MS_NOSEC; 9414b82d6e4SYan strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); 9425f524444SIlya Dryomov btrfs_sb(s)->fs_info->bdev_holder = fs_type; 9438a4b83ccSChris Mason error = btrfs_fill_super(s, fs_devices, data, 9448a4b83ccSChris Mason flags & MS_SILENT ? 1 : 0); 9454b82d6e4SYan } 9464b82d6e4SYan 947*59553edfSAl Viro root = !error ? get_default_root(s, subvol_objectid) : ERR_PTR(error); 948*59553edfSAl Viro if (IS_ERR(root)) 949e15d0542SXin Zhong deactivate_locked_super(s); 9504b82d6e4SYan 951061dbc6bSAl Viro return root; 9524b82d6e4SYan 953c146afadSYan Zheng error_close_devices: 9548a4b83ccSChris Mason btrfs_close_devices(fs_devices); 95504d21a24SIlya Dryomov error_fs_info: 9566c41761fSDavid Sterba free_fs_info(fs_info); 957061dbc6bSAl Viro return ERR_PTR(error); 9584b82d6e4SYan } 9592e635a27SChris Mason 960c146afadSYan Zheng static int btrfs_remount(struct super_block *sb, int *flags, char *data) 961c146afadSYan Zheng { 962c146afadSYan Zheng struct btrfs_root *root = btrfs_sb(sb); 963c146afadSYan Zheng int ret; 964c146afadSYan Zheng 965b288052eSChris Mason ret = btrfs_parse_options(root, data); 966b288052eSChris Mason if (ret) 967b288052eSChris Mason return -EINVAL; 968b288052eSChris Mason 969c146afadSYan Zheng if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 970c146afadSYan Zheng return 0; 971c146afadSYan Zheng 972c146afadSYan Zheng if (*flags & MS_RDONLY) { 973c146afadSYan Zheng sb->s_flags |= MS_RDONLY; 974c146afadSYan Zheng 975c146afadSYan Zheng ret = btrfs_commit_super(root); 976c146afadSYan Zheng WARN_ON(ret); 977c146afadSYan Zheng } else { 9782b82032cSYan Zheng if (root->fs_info->fs_devices->rw_devices == 0) 9792b82032cSYan Zheng return -EACCES; 9802b82032cSYan Zheng 9816c41761fSDavid Sterba if (btrfs_super_log_root(root->fs_info->super_copy) != 0) 982c146afadSYan Zheng return -EINVAL; 983c146afadSYan Zheng 984d68fc57bSYan, Zheng ret = btrfs_cleanup_fs_roots(root->fs_info); 985c146afadSYan Zheng WARN_ON(ret); 986c146afadSYan Zheng 987d68fc57bSYan, Zheng /* recover relocation */ 988d68fc57bSYan, Zheng ret = btrfs_recover_relocation(root); 989c146afadSYan Zheng WARN_ON(ret); 990c146afadSYan Zheng 991c146afadSYan Zheng sb->s_flags &= ~MS_RDONLY; 992c146afadSYan Zheng } 993c146afadSYan Zheng 994c146afadSYan Zheng return 0; 995c146afadSYan Zheng } 996c146afadSYan Zheng 997bcd53741SArne Jansen /* Used to sort the devices by max_avail(descending sort) */ 998bcd53741SArne Jansen static int btrfs_cmp_device_free_bytes(const void *dev_info1, 999bcd53741SArne Jansen const void *dev_info2) 1000bcd53741SArne Jansen { 1001bcd53741SArne Jansen if (((struct btrfs_device_info *)dev_info1)->max_avail > 1002bcd53741SArne Jansen ((struct btrfs_device_info *)dev_info2)->max_avail) 1003bcd53741SArne Jansen return -1; 1004bcd53741SArne Jansen else if (((struct btrfs_device_info *)dev_info1)->max_avail < 1005bcd53741SArne Jansen ((struct btrfs_device_info *)dev_info2)->max_avail) 1006bcd53741SArne Jansen return 1; 1007bcd53741SArne Jansen else 1008bcd53741SArne Jansen return 0; 1009bcd53741SArne Jansen } 1010bcd53741SArne Jansen 1011bcd53741SArne Jansen /* 1012bcd53741SArne Jansen * sort the devices by max_avail, in which max free extent size of each device 1013bcd53741SArne Jansen * is stored.(Descending Sort) 1014bcd53741SArne Jansen */ 1015bcd53741SArne Jansen static inline void btrfs_descending_sort_devices( 1016bcd53741SArne Jansen struct btrfs_device_info *devices, 1017bcd53741SArne Jansen size_t nr_devices) 1018bcd53741SArne Jansen { 1019bcd53741SArne Jansen sort(devices, nr_devices, sizeof(struct btrfs_device_info), 1020bcd53741SArne Jansen btrfs_cmp_device_free_bytes, NULL); 1021bcd53741SArne Jansen } 1022bcd53741SArne Jansen 10236d07bcecSMiao Xie /* 10246d07bcecSMiao Xie * The helper to calc the free space on the devices that can be used to store 10256d07bcecSMiao Xie * file data. 10266d07bcecSMiao Xie */ 10276d07bcecSMiao Xie static int btrfs_calc_avail_data_space(struct btrfs_root *root, u64 *free_bytes) 10286d07bcecSMiao Xie { 10296d07bcecSMiao Xie struct btrfs_fs_info *fs_info = root->fs_info; 10306d07bcecSMiao Xie struct btrfs_device_info *devices_info; 10316d07bcecSMiao Xie struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 10326d07bcecSMiao Xie struct btrfs_device *device; 10336d07bcecSMiao Xie u64 skip_space; 10346d07bcecSMiao Xie u64 type; 10356d07bcecSMiao Xie u64 avail_space; 10366d07bcecSMiao Xie u64 used_space; 10376d07bcecSMiao Xie u64 min_stripe_size; 103839fb26c3SMiao Xie int min_stripes = 1, num_stripes = 1; 10396d07bcecSMiao Xie int i = 0, nr_devices; 10406d07bcecSMiao Xie int ret; 10416d07bcecSMiao Xie 1042b772a86eSLi Zefan nr_devices = fs_info->fs_devices->open_devices; 10436d07bcecSMiao Xie BUG_ON(!nr_devices); 10446d07bcecSMiao Xie 10456d07bcecSMiao Xie devices_info = kmalloc(sizeof(*devices_info) * nr_devices, 10466d07bcecSMiao Xie GFP_NOFS); 10476d07bcecSMiao Xie if (!devices_info) 10486d07bcecSMiao Xie return -ENOMEM; 10496d07bcecSMiao Xie 10506d07bcecSMiao Xie /* calc min stripe number for data space alloction */ 10516d07bcecSMiao Xie type = btrfs_get_alloc_profile(root, 1); 105239fb26c3SMiao Xie if (type & BTRFS_BLOCK_GROUP_RAID0) { 10536d07bcecSMiao Xie min_stripes = 2; 105439fb26c3SMiao Xie num_stripes = nr_devices; 105539fb26c3SMiao Xie } else if (type & BTRFS_BLOCK_GROUP_RAID1) { 10566d07bcecSMiao Xie min_stripes = 2; 105739fb26c3SMiao Xie num_stripes = 2; 105839fb26c3SMiao Xie } else if (type & BTRFS_BLOCK_GROUP_RAID10) { 10596d07bcecSMiao Xie min_stripes = 4; 106039fb26c3SMiao Xie num_stripes = 4; 106139fb26c3SMiao Xie } 10626d07bcecSMiao Xie 10636d07bcecSMiao Xie if (type & BTRFS_BLOCK_GROUP_DUP) 10646d07bcecSMiao Xie min_stripe_size = 2 * BTRFS_STRIPE_LEN; 10656d07bcecSMiao Xie else 10666d07bcecSMiao Xie min_stripe_size = BTRFS_STRIPE_LEN; 10676d07bcecSMiao Xie 1068b772a86eSLi Zefan list_for_each_entry(device, &fs_devices->devices, dev_list) { 1069b772a86eSLi Zefan if (!device->in_fs_metadata || !device->bdev) 10706d07bcecSMiao Xie continue; 10716d07bcecSMiao Xie 10726d07bcecSMiao Xie avail_space = device->total_bytes - device->bytes_used; 10736d07bcecSMiao Xie 10746d07bcecSMiao Xie /* align with stripe_len */ 10756d07bcecSMiao Xie do_div(avail_space, BTRFS_STRIPE_LEN); 10766d07bcecSMiao Xie avail_space *= BTRFS_STRIPE_LEN; 10776d07bcecSMiao Xie 10786d07bcecSMiao Xie /* 10796d07bcecSMiao Xie * In order to avoid overwritting the superblock on the drive, 10806d07bcecSMiao Xie * btrfs starts at an offset of at least 1MB when doing chunk 10816d07bcecSMiao Xie * allocation. 10826d07bcecSMiao Xie */ 10836d07bcecSMiao Xie skip_space = 1024 * 1024; 10846d07bcecSMiao Xie 10856d07bcecSMiao Xie /* user can set the offset in fs_info->alloc_start. */ 10866d07bcecSMiao Xie if (fs_info->alloc_start + BTRFS_STRIPE_LEN <= 10876d07bcecSMiao Xie device->total_bytes) 10886d07bcecSMiao Xie skip_space = max(fs_info->alloc_start, skip_space); 10896d07bcecSMiao Xie 10906d07bcecSMiao Xie /* 10916d07bcecSMiao Xie * btrfs can not use the free space in [0, skip_space - 1], 10926d07bcecSMiao Xie * we must subtract it from the total. In order to implement 10936d07bcecSMiao Xie * it, we account the used space in this range first. 10946d07bcecSMiao Xie */ 10956d07bcecSMiao Xie ret = btrfs_account_dev_extents_size(device, 0, skip_space - 1, 10966d07bcecSMiao Xie &used_space); 10976d07bcecSMiao Xie if (ret) { 10986d07bcecSMiao Xie kfree(devices_info); 10996d07bcecSMiao Xie return ret; 11006d07bcecSMiao Xie } 11016d07bcecSMiao Xie 11026d07bcecSMiao Xie /* calc the free space in [0, skip_space - 1] */ 11036d07bcecSMiao Xie skip_space -= used_space; 11046d07bcecSMiao Xie 11056d07bcecSMiao Xie /* 11066d07bcecSMiao Xie * we can use the free space in [0, skip_space - 1], subtract 11076d07bcecSMiao Xie * it from the total. 11086d07bcecSMiao Xie */ 11096d07bcecSMiao Xie if (avail_space && avail_space >= skip_space) 11106d07bcecSMiao Xie avail_space -= skip_space; 11116d07bcecSMiao Xie else 11126d07bcecSMiao Xie avail_space = 0; 11136d07bcecSMiao Xie 11146d07bcecSMiao Xie if (avail_space < min_stripe_size) 11156d07bcecSMiao Xie continue; 11166d07bcecSMiao Xie 11176d07bcecSMiao Xie devices_info[i].dev = device; 11186d07bcecSMiao Xie devices_info[i].max_avail = avail_space; 11196d07bcecSMiao Xie 11206d07bcecSMiao Xie i++; 11216d07bcecSMiao Xie } 11226d07bcecSMiao Xie 11236d07bcecSMiao Xie nr_devices = i; 11246d07bcecSMiao Xie 11256d07bcecSMiao Xie btrfs_descending_sort_devices(devices_info, nr_devices); 11266d07bcecSMiao Xie 11276d07bcecSMiao Xie i = nr_devices - 1; 11286d07bcecSMiao Xie avail_space = 0; 11296d07bcecSMiao Xie while (nr_devices >= min_stripes) { 113039fb26c3SMiao Xie if (num_stripes > nr_devices) 113139fb26c3SMiao Xie num_stripes = nr_devices; 113239fb26c3SMiao Xie 11336d07bcecSMiao Xie if (devices_info[i].max_avail >= min_stripe_size) { 11346d07bcecSMiao Xie int j; 11356d07bcecSMiao Xie u64 alloc_size; 11366d07bcecSMiao Xie 113739fb26c3SMiao Xie avail_space += devices_info[i].max_avail * num_stripes; 11386d07bcecSMiao Xie alloc_size = devices_info[i].max_avail; 113939fb26c3SMiao Xie for (j = i + 1 - num_stripes; j <= i; j++) 11406d07bcecSMiao Xie devices_info[j].max_avail -= alloc_size; 11416d07bcecSMiao Xie } 11426d07bcecSMiao Xie i--; 11436d07bcecSMiao Xie nr_devices--; 11446d07bcecSMiao Xie } 11456d07bcecSMiao Xie 11466d07bcecSMiao Xie kfree(devices_info); 11476d07bcecSMiao Xie *free_bytes = avail_space; 11486d07bcecSMiao Xie return 0; 11496d07bcecSMiao Xie } 11506d07bcecSMiao Xie 11518fd17795SChris Mason static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) 11528fd17795SChris Mason { 11538fd17795SChris Mason struct btrfs_root *root = btrfs_sb(dentry->d_sb); 11546c41761fSDavid Sterba struct btrfs_super_block *disk_super = root->fs_info->super_copy; 1155bd4d1088SJosef Bacik struct list_head *head = &root->fs_info->space_info; 1156bd4d1088SJosef Bacik struct btrfs_space_info *found; 1157bd4d1088SJosef Bacik u64 total_used = 0; 11586d07bcecSMiao Xie u64 total_free_data = 0; 1159db94535dSChris Mason int bits = dentry->d_sb->s_blocksize_bits; 11609d03632eSDavid Woodhouse __be32 *fsid = (__be32 *)root->fs_info->fsid; 11616d07bcecSMiao Xie int ret; 11628fd17795SChris Mason 11636d07bcecSMiao Xie /* holding chunk_muext to avoid allocating new chunks */ 11646d07bcecSMiao Xie mutex_lock(&root->fs_info->chunk_mutex); 1165bd4d1088SJosef Bacik rcu_read_lock(); 116689a55897SJosef Bacik list_for_each_entry_rcu(found, head, list) { 11676d07bcecSMiao Xie if (found->flags & BTRFS_BLOCK_GROUP_DATA) { 11686d07bcecSMiao Xie total_free_data += found->disk_total - found->disk_used; 11696d07bcecSMiao Xie total_free_data -= 11706d07bcecSMiao Xie btrfs_account_ro_block_groups_free_space(found); 11716d07bcecSMiao Xie } 11726d07bcecSMiao Xie 1173b742bb82SYan, Zheng total_used += found->disk_used; 117489a55897SJosef Bacik } 1175bd4d1088SJosef Bacik rcu_read_unlock(); 1176bd4d1088SJosef Bacik 11778fd17795SChris Mason buf->f_namelen = BTRFS_NAME_LEN; 1178db94535dSChris Mason buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; 1179bd4d1088SJosef Bacik buf->f_bfree = buf->f_blocks - (total_used >> bits); 11808fd17795SChris Mason buf->f_bsize = dentry->d_sb->s_blocksize; 11818fd17795SChris Mason buf->f_type = BTRFS_SUPER_MAGIC; 11826d07bcecSMiao Xie buf->f_bavail = total_free_data; 11836d07bcecSMiao Xie ret = btrfs_calc_avail_data_space(root, &total_free_data); 11846d07bcecSMiao Xie if (ret) { 11856d07bcecSMiao Xie mutex_unlock(&root->fs_info->chunk_mutex); 11866d07bcecSMiao Xie return ret; 11876d07bcecSMiao Xie } 11886d07bcecSMiao Xie buf->f_bavail += total_free_data; 11896d07bcecSMiao Xie buf->f_bavail = buf->f_bavail >> bits; 11906d07bcecSMiao Xie mutex_unlock(&root->fs_info->chunk_mutex); 1191d397712bSChris Mason 11929d03632eSDavid Woodhouse /* We treat it as constant endianness (it doesn't matter _which_) 11939d03632eSDavid Woodhouse because we want the fsid to come out the same whether mounted 11949d03632eSDavid Woodhouse on a big-endian or little-endian host */ 11959d03632eSDavid Woodhouse buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); 11969d03632eSDavid Woodhouse buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); 119732d48fa1SDavid Woodhouse /* Mask in the root object ID too, to disambiguate subvols */ 119832d48fa1SDavid Woodhouse buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; 119932d48fa1SDavid Woodhouse buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; 120032d48fa1SDavid Woodhouse 12018fd17795SChris Mason return 0; 12028fd17795SChris Mason } 1203b5133862SChris Mason 1204aea52e19SAl Viro static void btrfs_kill_super(struct super_block *sb) 1205aea52e19SAl Viro { 1206d22ca7deSAl Viro struct btrfs_fs_info *fs_info = btrfs_sb(sb)->fs_info; 1207aea52e19SAl Viro kill_anon_super(sb); 1208aea52e19SAl Viro free_fs_info(fs_info); 1209aea52e19SAl Viro } 1210aea52e19SAl Viro 12112e635a27SChris Mason static struct file_system_type btrfs_fs_type = { 12122e635a27SChris Mason .owner = THIS_MODULE, 12132e635a27SChris Mason .name = "btrfs", 1214061dbc6bSAl Viro .mount = btrfs_mount, 1215aea52e19SAl Viro .kill_sb = btrfs_kill_super, 12162e635a27SChris Mason .fs_flags = FS_REQUIRES_DEV, 12172e635a27SChris Mason }; 1218a9218f6bSChris Mason 1219d352ac68SChris Mason /* 1220d352ac68SChris Mason * used by btrfsctl to scan devices when no FS is mounted 1221d352ac68SChris Mason */ 12228a4b83ccSChris Mason static long btrfs_control_ioctl(struct file *file, unsigned int cmd, 12238a4b83ccSChris Mason unsigned long arg) 12248a4b83ccSChris Mason { 12258a4b83ccSChris Mason struct btrfs_ioctl_vol_args *vol; 12268a4b83ccSChris Mason struct btrfs_fs_devices *fs_devices; 1227c071fcfdSChris Mason int ret = -ENOTTY; 12288a4b83ccSChris Mason 1229e441d54dSChris Mason if (!capable(CAP_SYS_ADMIN)) 1230e441d54dSChris Mason return -EPERM; 1231e441d54dSChris Mason 1232dae7b665SLi Zefan vol = memdup_user((void __user *)arg, sizeof(*vol)); 1233dae7b665SLi Zefan if (IS_ERR(vol)) 1234dae7b665SLi Zefan return PTR_ERR(vol); 1235c071fcfdSChris Mason 12368a4b83ccSChris Mason switch (cmd) { 12378a4b83ccSChris Mason case BTRFS_IOC_SCAN_DEV: 123897288f2cSChristoph Hellwig ret = btrfs_scan_one_device(vol->name, FMODE_READ, 12398a4b83ccSChris Mason &btrfs_fs_type, &fs_devices); 12408a4b83ccSChris Mason break; 12418a4b83ccSChris Mason } 1242dae7b665SLi Zefan 12438a4b83ccSChris Mason kfree(vol); 1244f819d837SLinda Knippers return ret; 12458a4b83ccSChris Mason } 12468a4b83ccSChris Mason 12470176260fSLinus Torvalds static int btrfs_freeze(struct super_block *sb) 1248ed0dab6bSYan { 1249ed0dab6bSYan struct btrfs_root *root = btrfs_sb(sb); 1250a74a4b97SChris Mason mutex_lock(&root->fs_info->transaction_kthread_mutex); 1251a74a4b97SChris Mason mutex_lock(&root->fs_info->cleaner_mutex); 12520176260fSLinus Torvalds return 0; 1253ed0dab6bSYan } 1254ed0dab6bSYan 12550176260fSLinus Torvalds static int btrfs_unfreeze(struct super_block *sb) 1256ed0dab6bSYan { 1257ed0dab6bSYan struct btrfs_root *root = btrfs_sb(sb); 1258a74a4b97SChris Mason mutex_unlock(&root->fs_info->cleaner_mutex); 1259a74a4b97SChris Mason mutex_unlock(&root->fs_info->transaction_kthread_mutex); 12600176260fSLinus Torvalds return 0; 1261ed0dab6bSYan } 12622e635a27SChris Mason 126322c44fe6SJosef Bacik static void btrfs_fs_dirty_inode(struct inode *inode, int flags) 126422c44fe6SJosef Bacik { 126522c44fe6SJosef Bacik int ret; 126622c44fe6SJosef Bacik 126722c44fe6SJosef Bacik ret = btrfs_dirty_inode(inode); 126822c44fe6SJosef Bacik if (ret) 126922c44fe6SJosef Bacik printk_ratelimited(KERN_ERR "btrfs: fail to dirty inode %Lu " 127022c44fe6SJosef Bacik "error %d\n", btrfs_ino(inode), ret); 127122c44fe6SJosef Bacik } 127222c44fe6SJosef Bacik 1273b87221deSAlexey Dobriyan static const struct super_operations btrfs_super_ops = { 127476dda93cSYan, Zheng .drop_inode = btrfs_drop_inode, 1275bd555975SAl Viro .evict_inode = btrfs_evict_inode, 1276e20d96d6SChris Mason .put_super = btrfs_put_super, 1277d5719762SChris Mason .sync_fs = btrfs_sync_fs, 1278a9572a15SEric Paris .show_options = btrfs_show_options, 12794730a4bcSChris Mason .write_inode = btrfs_write_inode, 128022c44fe6SJosef Bacik .dirty_inode = btrfs_fs_dirty_inode, 12812c90e5d6SChris Mason .alloc_inode = btrfs_alloc_inode, 12822c90e5d6SChris Mason .destroy_inode = btrfs_destroy_inode, 12838fd17795SChris Mason .statfs = btrfs_statfs, 1284c146afadSYan Zheng .remount_fs = btrfs_remount, 12850176260fSLinus Torvalds .freeze_fs = btrfs_freeze, 12860176260fSLinus Torvalds .unfreeze_fs = btrfs_unfreeze, 1287e20d96d6SChris Mason }; 1288a9218f6bSChris Mason 1289a9218f6bSChris Mason static const struct file_operations btrfs_ctl_fops = { 1290a9218f6bSChris Mason .unlocked_ioctl = btrfs_control_ioctl, 1291a9218f6bSChris Mason .compat_ioctl = btrfs_control_ioctl, 1292a9218f6bSChris Mason .owner = THIS_MODULE, 12936038f373SArnd Bergmann .llseek = noop_llseek, 1294a9218f6bSChris Mason }; 1295a9218f6bSChris Mason 1296a9218f6bSChris Mason static struct miscdevice btrfs_misc = { 1297578454ffSKay Sievers .minor = BTRFS_MINOR, 1298a9218f6bSChris Mason .name = "btrfs-control", 1299a9218f6bSChris Mason .fops = &btrfs_ctl_fops 1300a9218f6bSChris Mason }; 1301a9218f6bSChris Mason 1302578454ffSKay Sievers MODULE_ALIAS_MISCDEV(BTRFS_MINOR); 1303578454ffSKay Sievers MODULE_ALIAS("devname:btrfs-control"); 1304578454ffSKay Sievers 1305a9218f6bSChris Mason static int btrfs_interface_init(void) 1306a9218f6bSChris Mason { 1307a9218f6bSChris Mason return misc_register(&btrfs_misc); 1308a9218f6bSChris Mason } 1309a9218f6bSChris Mason 1310b2950863SChristoph Hellwig static void btrfs_interface_exit(void) 1311a9218f6bSChris Mason { 1312a9218f6bSChris Mason if (misc_deregister(&btrfs_misc) < 0) 1313d397712bSChris Mason printk(KERN_INFO "misc_deregister failed for control device"); 1314a9218f6bSChris Mason } 1315a9218f6bSChris Mason 13162e635a27SChris Mason static int __init init_btrfs_fs(void) 13172e635a27SChris Mason { 13182c90e5d6SChris Mason int err; 131958176a96SJosef Bacik 132058176a96SJosef Bacik err = btrfs_init_sysfs(); 132158176a96SJosef Bacik if (err) 132258176a96SJosef Bacik return err; 132358176a96SJosef Bacik 1324261507a0SLi Zefan err = btrfs_init_compress(); 13252c90e5d6SChris Mason if (err) 1326a74a4b97SChris Mason goto free_sysfs; 1327d1310b2eSChris Mason 1328261507a0SLi Zefan err = btrfs_init_cachep(); 1329261507a0SLi Zefan if (err) 1330261507a0SLi Zefan goto free_compress; 1331261507a0SLi Zefan 1332d1310b2eSChris Mason err = extent_io_init(); 13332f4cbe64SWyatt Banks if (err) 13342f4cbe64SWyatt Banks goto free_cachep; 13352f4cbe64SWyatt Banks 1336d1310b2eSChris Mason err = extent_map_init(); 1337d1310b2eSChris Mason if (err) 1338d1310b2eSChris Mason goto free_extent_io; 1339d1310b2eSChris Mason 134016cdcec7SMiao Xie err = btrfs_delayed_inode_init(); 13412f4cbe64SWyatt Banks if (err) 13422f4cbe64SWyatt Banks goto free_extent_map; 1343c8b97818SChris Mason 134416cdcec7SMiao Xie err = btrfs_interface_init(); 134516cdcec7SMiao Xie if (err) 134616cdcec7SMiao Xie goto free_delayed_inode; 134716cdcec7SMiao Xie 1348a9218f6bSChris Mason err = register_filesystem(&btrfs_fs_type); 1349a9218f6bSChris Mason if (err) 1350a9218f6bSChris Mason goto unregister_ioctl; 1351b3c3da71SChris Mason 1352b3c3da71SChris Mason printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); 13532f4cbe64SWyatt Banks return 0; 13542f4cbe64SWyatt Banks 1355a9218f6bSChris Mason unregister_ioctl: 1356a9218f6bSChris Mason btrfs_interface_exit(); 135716cdcec7SMiao Xie free_delayed_inode: 135816cdcec7SMiao Xie btrfs_delayed_inode_exit(); 13592f4cbe64SWyatt Banks free_extent_map: 13602f4cbe64SWyatt Banks extent_map_exit(); 1361d1310b2eSChris Mason free_extent_io: 1362d1310b2eSChris Mason extent_io_exit(); 13632f4cbe64SWyatt Banks free_cachep: 13642f4cbe64SWyatt Banks btrfs_destroy_cachep(); 1365261507a0SLi Zefan free_compress: 1366261507a0SLi Zefan btrfs_exit_compress(); 1367a74a4b97SChris Mason free_sysfs: 13682f4cbe64SWyatt Banks btrfs_exit_sysfs(); 13692c90e5d6SChris Mason return err; 13702e635a27SChris Mason } 13712e635a27SChris Mason 13722e635a27SChris Mason static void __exit exit_btrfs_fs(void) 13732e635a27SChris Mason { 137439279cc3SChris Mason btrfs_destroy_cachep(); 137516cdcec7SMiao Xie btrfs_delayed_inode_exit(); 1376a52d9a80SChris Mason extent_map_exit(); 1377d1310b2eSChris Mason extent_io_exit(); 1378a9218f6bSChris Mason btrfs_interface_exit(); 13792e635a27SChris Mason unregister_filesystem(&btrfs_fs_type); 138058176a96SJosef Bacik btrfs_exit_sysfs(); 13818a4b83ccSChris Mason btrfs_cleanup_fs_uuids(); 1382261507a0SLi Zefan btrfs_exit_compress(); 13832e635a27SChris Mason } 13842e635a27SChris Mason 13852e635a27SChris Mason module_init(init_btrfs_fs) 13862e635a27SChris Mason module_exit(exit_btrfs_fs) 13872e635a27SChris Mason 13882e635a27SChris Mason MODULE_LICENSE("GPL"); 1389