Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2 | * linux/fs/ext4/file.c |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 3 | * |
| 4 | * Copyright (C) 1992, 1993, 1994, 1995 |
| 5 | * Remy Card (card@masi.ibp.fr) |
| 6 | * Laboratoire MASI - Institut Blaise Pascal |
| 7 | * Universite Pierre et Marie Curie (Paris VI) |
| 8 | * |
| 9 | * from |
| 10 | * |
| 11 | * linux/fs/minix/file.c |
| 12 | * |
| 13 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 14 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 15 | * ext4 fs regular file handling primitives |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 16 | * |
| 17 | * 64-bit file support on 64-bit platforms by Jakub Jelinek |
| 18 | * (jj@sunsite.ms.mff.cuni.cz) |
| 19 | */ |
| 20 | |
| 21 | #include <linux/time.h> |
| 22 | #include <linux/fs.h> |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 23 | #include <linux/jbd2.h> |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 24 | #include <linux/mount.h> |
| 25 | #include <linux/path.h> |
Christoph Hellwig | 871a293 | 2010-03-03 09:05:07 -0500 | [diff] [blame] | 26 | #include <linux/quotaops.h> |
Christoph Hellwig | 3dcf545 | 2008-04-29 18:13:32 -0400 | [diff] [blame] | 27 | #include "ext4.h" |
| 28 | #include "ext4_jbd2.h" |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 29 | #include "xattr.h" |
| 30 | #include "acl.h" |
| 31 | |
| 32 | /* |
| 33 | * Called when an inode is released. Note that this is different |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 34 | * from ext4_file_open: open gets called at every open, but release |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 35 | * gets called only when /all/ the files are closed. |
| 36 | */ |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 37 | static int ext4_release_file(struct inode *inode, struct file *filp) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 38 | { |
Theodore Ts'o | 19f5fb7 | 2010-01-24 14:34:07 -0500 | [diff] [blame] | 39 | if (ext4_test_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE)) { |
Theodore Ts'o | 7d8f9f7 | 2009-02-24 08:21:14 -0500 | [diff] [blame] | 40 | ext4_alloc_da_blocks(inode); |
Theodore Ts'o | 19f5fb7 | 2010-01-24 14:34:07 -0500 | [diff] [blame] | 41 | ext4_clear_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE); |
Theodore Ts'o | 7d8f9f7 | 2009-02-24 08:21:14 -0500 | [diff] [blame] | 42 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 43 | /* if we are the last writer on the inode, drop the block reservation */ |
| 44 | if ((filp->f_mode & FMODE_WRITE) && |
Aneesh Kumar K.V | d601430 | 2009-03-27 22:36:43 -0400 | [diff] [blame] | 45 | (atomic_read(&inode->i_writecount) == 1) && |
| 46 | !EXT4_I(inode)->i_reserved_data_blocks) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 47 | { |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 48 | down_write(&EXT4_I(inode)->i_data_sem); |
Theodore Ts'o | c2ea3fd | 2008-10-10 09:40:52 -0400 | [diff] [blame] | 49 | ext4_discard_preallocations(inode); |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 50 | up_write(&EXT4_I(inode)->i_data_sem); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 51 | } |
| 52 | if (is_dx(inode) && filp->private_data) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 53 | ext4_htree_free_dir_info(filp->private_data); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 54 | |
| 55 | return 0; |
| 56 | } |
| 57 | |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 58 | static void ext4_aiodio_wait(struct inode *inode) |
| 59 | { |
| 60 | wait_queue_head_t *wq = ext4_ioend_wq(inode); |
| 61 | |
| 62 | wait_event(*wq, (atomic_read(&EXT4_I(inode)->i_aiodio_unwritten) == 0)); |
| 63 | } |
| 64 | |
| 65 | /* |
| 66 | * This tests whether the IO in question is block-aligned or not. |
| 67 | * Ext4 utilizes unwritten extents when hole-filling during direct IO, and they |
| 68 | * are converted to written only after the IO is complete. Until they are |
| 69 | * mapped, these blocks appear as holes, so dio_zero_block() will assume that |
| 70 | * it needs to zero out portions of the start and/or end block. If 2 AIO |
| 71 | * threads are at work on the same unwritten block, they must be synchronized |
| 72 | * or one thread will zero the other's data, causing corruption. |
| 73 | */ |
| 74 | static int |
| 75 | ext4_unaligned_aio(struct inode *inode, const struct iovec *iov, |
| 76 | unsigned long nr_segs, loff_t pos) |
| 77 | { |
| 78 | struct super_block *sb = inode->i_sb; |
| 79 | int blockmask = sb->s_blocksize - 1; |
| 80 | size_t count = iov_length(iov, nr_segs); |
| 81 | loff_t final_size = pos + count; |
| 82 | |
| 83 | if (pos >= inode->i_size) |
| 84 | return 0; |
| 85 | |
| 86 | if ((pos & blockmask) || (final_size & blockmask)) |
| 87 | return 1; |
| 88 | |
| 89 | return 0; |
| 90 | } |
| 91 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 92 | static ssize_t |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 93 | ext4_file_write(struct kiocb *iocb, const struct iovec *iov, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 94 | unsigned long nr_segs, loff_t pos) |
| 95 | { |
Jan Kara | 0d34ec6 | 2009-08-18 17:48:27 +0200 | [diff] [blame] | 96 | struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode; |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 97 | int unaligned_aio = 0; |
| 98 | int ret; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 99 | |
Eric Sandeen | e2b4657 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 100 | /* |
| 101 | * If we have encountered a bitmap-format file, the size limit |
| 102 | * is smaller than s_maxbytes, which is for extent-mapped files. |
| 103 | */ |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 104 | |
Dmitry Monakhov | 12e9b89 | 2010-05-16 22:00:00 -0400 | [diff] [blame] | 105 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) { |
Eric Sandeen | e2b4657 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 106 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 107 | size_t length = iov_length(iov, nr_segs); |
| 108 | |
Toshiyuki Okajima | d889dc8 | 2010-07-27 11:56:07 -0400 | [diff] [blame] | 109 | if ((pos > sbi->s_bitmap_maxbytes || |
| 110 | (pos == sbi->s_bitmap_maxbytes && length > 0))) |
Eric Sandeen | e2b4657 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 111 | return -EFBIG; |
| 112 | |
| 113 | if (pos + length > sbi->s_bitmap_maxbytes) { |
| 114 | nr_segs = iov_shorten((struct iovec *)iov, nr_segs, |
| 115 | sbi->s_bitmap_maxbytes - pos); |
| 116 | } |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 117 | } else if (unlikely((iocb->ki_filp->f_flags & O_DIRECT) && |
| 118 | !is_sync_kiocb(iocb))) { |
| 119 | unaligned_aio = ext4_unaligned_aio(inode, iov, nr_segs, pos); |
Eric Sandeen | e2b4657 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 120 | } |
| 121 | |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 122 | /* Unaligned direct AIO must be serialized; see comment above */ |
| 123 | if (unaligned_aio) { |
| 124 | static unsigned long unaligned_warn_time; |
| 125 | |
| 126 | /* Warn about this once per day */ |
| 127 | if (printk_timed_ratelimit(&unaligned_warn_time, 60*60*24*HZ)) |
| 128 | ext4_msg(inode->i_sb, KERN_WARNING, |
| 129 | "Unaligned AIO/DIO on inode %ld by %s; " |
| 130 | "performance will be poor.", |
| 131 | inode->i_ino, current->comm); |
| 132 | mutex_lock(ext4_aio_mutex(inode)); |
| 133 | ext4_aiodio_wait(inode); |
| 134 | } |
| 135 | |
| 136 | ret = generic_file_aio_write(iocb, iov, nr_segs, pos); |
| 137 | |
| 138 | if (unaligned_aio) |
| 139 | mutex_unlock(ext4_aio_mutex(inode)); |
| 140 | |
| 141 | return ret; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 142 | } |
| 143 | |
Alexey Dobriyan | f0f37e2 | 2009-09-27 22:29:37 +0400 | [diff] [blame] | 144 | static const struct vm_operations_struct ext4_file_vm_ops = { |
Aneesh Kumar K.V | 2e9ee85 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 145 | .fault = filemap_fault, |
| 146 | .page_mkwrite = ext4_page_mkwrite, |
| 147 | }; |
| 148 | |
| 149 | static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma) |
| 150 | { |
| 151 | struct address_space *mapping = file->f_mapping; |
| 152 | |
| 153 | if (!mapping->a_ops->readpage) |
| 154 | return -ENOEXEC; |
| 155 | file_accessed(file); |
| 156 | vma->vm_ops = &ext4_file_vm_ops; |
| 157 | vma->vm_flags |= VM_CAN_NONLINEAR; |
| 158 | return 0; |
| 159 | } |
| 160 | |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 161 | static int ext4_file_open(struct inode * inode, struct file * filp) |
| 162 | { |
| 163 | struct super_block *sb = inode->i_sb; |
| 164 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
Theodore Ts'o | 8aefcd5 | 2011-01-10 12:29:43 -0500 | [diff] [blame] | 165 | struct ext4_inode_info *ei = EXT4_I(inode); |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 166 | struct vfsmount *mnt = filp->f_path.mnt; |
| 167 | struct path path; |
| 168 | char buf[64], *cp; |
| 169 | |
| 170 | if (unlikely(!(sbi->s_mount_flags & EXT4_MF_MNTDIR_SAMPLED) && |
| 171 | !(sb->s_flags & MS_RDONLY))) { |
| 172 | sbi->s_mount_flags |= EXT4_MF_MNTDIR_SAMPLED; |
| 173 | /* |
| 174 | * Sample where the filesystem has been mounted and |
| 175 | * store it in the superblock for sysadmin convenience |
| 176 | * when trying to sort through large numbers of block |
| 177 | * devices or filesystem images. |
| 178 | */ |
| 179 | memset(buf, 0, sizeof(buf)); |
Al Viro | 3899167 | 2010-01-23 20:10:29 -0500 | [diff] [blame] | 180 | path.mnt = mnt; |
| 181 | path.dentry = mnt->mnt_root; |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 182 | cp = d_path(&path, buf, sizeof(buf)); |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 183 | if (!IS_ERR(cp)) { |
| 184 | memcpy(sbi->s_es->s_last_mounted, cp, |
| 185 | sizeof(sbi->s_es->s_last_mounted)); |
Theodore Ts'o | a037515 | 2010-06-11 23:14:04 -0400 | [diff] [blame] | 186 | ext4_mark_super_dirty(sb); |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 187 | } |
| 188 | } |
Theodore Ts'o | 8aefcd5 | 2011-01-10 12:29:43 -0500 | [diff] [blame] | 189 | /* |
| 190 | * Set up the jbd2_inode if we are opening the inode for |
| 191 | * writing and the journal is present |
| 192 | */ |
| 193 | if (sbi->s_journal && !ei->jinode && (filp->f_mode & FMODE_WRITE)) { |
| 194 | struct jbd2_inode *jinode = jbd2_alloc_inode(GFP_KERNEL); |
| 195 | |
| 196 | spin_lock(&inode->i_lock); |
| 197 | if (!ei->jinode) { |
| 198 | if (!jinode) { |
| 199 | spin_unlock(&inode->i_lock); |
| 200 | return -ENOMEM; |
| 201 | } |
| 202 | ei->jinode = jinode; |
| 203 | jbd2_journal_init_jbd_inode(ei->jinode, inode); |
| 204 | jinode = NULL; |
| 205 | } |
| 206 | spin_unlock(&inode->i_lock); |
| 207 | if (unlikely(jinode != NULL)) |
| 208 | jbd2_free_inode(jinode); |
| 209 | } |
Christoph Hellwig | 907f455 | 2010-03-03 09:05:06 -0500 | [diff] [blame] | 210 | return dquot_file_open(inode, filp); |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 211 | } |
| 212 | |
Toshiyuki Okajima | e0d10bf | 2010-10-27 21:30:06 -0400 | [diff] [blame] | 213 | /* |
| 214 | * ext4_llseek() copied from generic_file_llseek() to handle both |
| 215 | * block-mapped and extent-mapped maxbytes values. This should |
| 216 | * otherwise be identical with generic_file_llseek(). |
| 217 | */ |
| 218 | loff_t ext4_llseek(struct file *file, loff_t offset, int origin) |
| 219 | { |
| 220 | struct inode *inode = file->f_mapping->host; |
| 221 | loff_t maxbytes; |
| 222 | |
| 223 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
| 224 | maxbytes = EXT4_SB(inode->i_sb)->s_bitmap_maxbytes; |
| 225 | else |
| 226 | maxbytes = inode->i_sb->s_maxbytes; |
| 227 | mutex_lock(&inode->i_mutex); |
| 228 | switch (origin) { |
| 229 | case SEEK_END: |
| 230 | offset += inode->i_size; |
| 231 | break; |
| 232 | case SEEK_CUR: |
| 233 | if (offset == 0) { |
| 234 | mutex_unlock(&inode->i_mutex); |
| 235 | return file->f_pos; |
| 236 | } |
| 237 | offset += file->f_pos; |
| 238 | break; |
Josef Bacik | c334b11 | 2011-07-18 13:21:37 -0400 | [diff] [blame] | 239 | case SEEK_DATA: |
| 240 | /* |
| 241 | * In the generic case the entire file is data, so as long as |
| 242 | * offset isn't at the end of the file then the offset is data. |
| 243 | */ |
| 244 | if (offset >= inode->i_size) { |
| 245 | mutex_unlock(&inode->i_mutex); |
| 246 | return -ENXIO; |
| 247 | } |
| 248 | break; |
| 249 | case SEEK_HOLE: |
| 250 | /* |
| 251 | * There is a virtual hole at the end of the file, so as long as |
| 252 | * offset isn't i_size or larger, return i_size. |
| 253 | */ |
| 254 | if (offset >= inode->i_size) { |
| 255 | mutex_unlock(&inode->i_mutex); |
| 256 | return -ENXIO; |
| 257 | } |
| 258 | offset = inode->i_size; |
| 259 | break; |
Toshiyuki Okajima | e0d10bf | 2010-10-27 21:30:06 -0400 | [diff] [blame] | 260 | } |
| 261 | |
| 262 | if (offset < 0 || offset > maxbytes) { |
| 263 | mutex_unlock(&inode->i_mutex); |
| 264 | return -EINVAL; |
| 265 | } |
| 266 | |
| 267 | if (offset != file->f_pos) { |
| 268 | file->f_pos = offset; |
| 269 | file->f_version = 0; |
| 270 | } |
| 271 | mutex_unlock(&inode->i_mutex); |
| 272 | |
| 273 | return offset; |
| 274 | } |
| 275 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 276 | const struct file_operations ext4_file_operations = { |
Toshiyuki Okajima | e0d10bf | 2010-10-27 21:30:06 -0400 | [diff] [blame] | 277 | .llseek = ext4_llseek, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 278 | .read = do_sync_read, |
| 279 | .write = do_sync_write, |
| 280 | .aio_read = generic_file_aio_read, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 281 | .aio_write = ext4_file_write, |
Andi Kleen | 5cdd7b2 | 2008-04-29 22:03:54 -0400 | [diff] [blame] | 282 | .unlocked_ioctl = ext4_ioctl, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 283 | #ifdef CONFIG_COMPAT |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 284 | .compat_ioctl = ext4_compat_ioctl, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 285 | #endif |
Aneesh Kumar K.V | 2e9ee85 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 286 | .mmap = ext4_file_mmap, |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 287 | .open = ext4_file_open, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 288 | .release = ext4_release_file, |
| 289 | .fsync = ext4_sync_file, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 290 | .splice_read = generic_file_splice_read, |
| 291 | .splice_write = generic_file_splice_write, |
Christoph Hellwig | 2fe17c1 | 2011-01-14 13:07:43 +0100 | [diff] [blame] | 292 | .fallocate = ext4_fallocate, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 293 | }; |
| 294 | |
Arjan van de Ven | 754661f | 2007-02-12 00:55:38 -0800 | [diff] [blame] | 295 | const struct inode_operations ext4_file_inode_operations = { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 296 | .setattr = ext4_setattr, |
Mingming Cao | 3e3398a | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 297 | .getattr = ext4_getattr, |
Theodore Ts'o | 03010a3 | 2008-10-10 20:02:48 -0400 | [diff] [blame] | 298 | #ifdef CONFIG_EXT4_FS_XATTR |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 299 | .setxattr = generic_setxattr, |
| 300 | .getxattr = generic_getxattr, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 301 | .listxattr = ext4_listxattr, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 302 | .removexattr = generic_removexattr, |
| 303 | #endif |
Christoph Hellwig | 4e34e71 | 2011-07-23 17:37:31 +0200 | [diff] [blame] | 304 | .get_acl = ext4_get_acl, |
Eric Sandeen | 6873fa0 | 2008-10-07 00:46:36 -0400 | [diff] [blame] | 305 | .fiemap = ext4_fiemap, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 306 | }; |
| 307 | |