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> |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 23 | #include <linux/mount.h> |
| 24 | #include <linux/path.h> |
Matthew Wilcox | c94c2ac | 2015-09-08 14:58:40 -0700 | [diff] [blame] | 25 | #include <linux/dax.h> |
Christoph Hellwig | 871a293 | 2010-03-03 09:05:07 -0500 | [diff] [blame] | 26 | #include <linux/quotaops.h> |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 27 | #include <linux/pagevec.h> |
Christoph Hellwig | e2e40f2 | 2015-02-22 08:58:50 -0800 | [diff] [blame] | 28 | #include <linux/uio.h> |
Christoph Hellwig | 3dcf545 | 2008-04-29 18:13:32 -0400 | [diff] [blame] | 29 | #include "ext4.h" |
| 30 | #include "ext4_jbd2.h" |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 31 | #include "xattr.h" |
| 32 | #include "acl.h" |
| 33 | |
Jan Kara | 364443c | 2016-11-20 17:36:06 -0500 | [diff] [blame] | 34 | #ifdef CONFIG_FS_DAX |
| 35 | static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) |
| 36 | { |
| 37 | struct inode *inode = file_inode(iocb->ki_filp); |
| 38 | ssize_t ret; |
| 39 | |
| 40 | inode_lock_shared(inode); |
| 41 | /* |
| 42 | * Recheck under inode lock - at this point we are sure it cannot |
| 43 | * change anymore |
| 44 | */ |
| 45 | if (!IS_DAX(inode)) { |
| 46 | inode_unlock_shared(inode); |
| 47 | /* Fallback to buffered IO in case we cannot support DAX */ |
| 48 | return generic_file_read_iter(iocb, to); |
| 49 | } |
| 50 | ret = dax_iomap_rw(iocb, to, &ext4_iomap_ops); |
| 51 | inode_unlock_shared(inode); |
| 52 | |
| 53 | file_accessed(iocb->ki_filp); |
| 54 | return ret; |
| 55 | } |
| 56 | #endif |
| 57 | |
| 58 | static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) |
| 59 | { |
| 60 | if (!iov_iter_count(to)) |
| 61 | return 0; /* skip atime */ |
| 62 | |
| 63 | #ifdef CONFIG_FS_DAX |
| 64 | if (IS_DAX(file_inode(iocb->ki_filp))) |
| 65 | return ext4_dax_read_iter(iocb, to); |
| 66 | #endif |
| 67 | return generic_file_read_iter(iocb, to); |
| 68 | } |
| 69 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 70 | /* |
| 71 | * Called when an inode is released. Note that this is different |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 72 | * from ext4_file_open: open gets called at every open, but release |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 73 | * gets called only when /all/ the files are closed. |
| 74 | */ |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 75 | static int ext4_release_file(struct inode *inode, struct file *filp) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 76 | { |
Theodore Ts'o | 19f5fb7 | 2010-01-24 14:34:07 -0500 | [diff] [blame] | 77 | if (ext4_test_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE)) { |
Theodore Ts'o | 7d8f9f7 | 2009-02-24 08:21:14 -0500 | [diff] [blame] | 78 | ext4_alloc_da_blocks(inode); |
Theodore Ts'o | 19f5fb7 | 2010-01-24 14:34:07 -0500 | [diff] [blame] | 79 | ext4_clear_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE); |
Theodore Ts'o | 7d8f9f7 | 2009-02-24 08:21:14 -0500 | [diff] [blame] | 80 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 81 | /* if we are the last writer on the inode, drop the block reservation */ |
| 82 | if ((filp->f_mode & FMODE_WRITE) && |
Aneesh Kumar K.V | d601430 | 2009-03-27 22:36:43 -0400 | [diff] [blame] | 83 | (atomic_read(&inode->i_writecount) == 1) && |
| 84 | !EXT4_I(inode)->i_reserved_data_blocks) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 85 | { |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 86 | down_write(&EXT4_I(inode)->i_data_sem); |
Theodore Ts'o | c2ea3fd | 2008-10-10 09:40:52 -0400 | [diff] [blame] | 87 | ext4_discard_preallocations(inode); |
Aneesh Kumar K.V | 0e855ac | 2008-01-28 23:58:26 -0500 | [diff] [blame] | 88 | up_write(&EXT4_I(inode)->i_data_sem); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 89 | } |
| 90 | if (is_dx(inode) && filp->private_data) |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 91 | ext4_htree_free_dir_info(filp->private_data); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 92 | |
| 93 | return 0; |
| 94 | } |
| 95 | |
Stephen Hemminger | c197855 | 2014-05-12 10:50:23 -0400 | [diff] [blame] | 96 | static void ext4_unwritten_wait(struct inode *inode) |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 97 | { |
| 98 | wait_queue_head_t *wq = ext4_ioend_wq(inode); |
| 99 | |
Dmitry Monakhov | e27f41e | 2012-09-28 23:24:52 -0400 | [diff] [blame] | 100 | wait_event(*wq, (atomic_read(&EXT4_I(inode)->i_unwritten) == 0)); |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 101 | } |
| 102 | |
| 103 | /* |
| 104 | * This tests whether the IO in question is block-aligned or not. |
| 105 | * Ext4 utilizes unwritten extents when hole-filling during direct IO, and they |
| 106 | * are converted to written only after the IO is complete. Until they are |
| 107 | * mapped, these blocks appear as holes, so dio_zero_block() will assume that |
| 108 | * it needs to zero out portions of the start and/or end block. If 2 AIO |
| 109 | * threads are at work on the same unwritten block, they must be synchronized |
| 110 | * or one thread will zero the other's data, causing corruption. |
| 111 | */ |
| 112 | static int |
Al Viro | 9b88416 | 2014-04-17 16:09:22 -0400 | [diff] [blame] | 113 | ext4_unaligned_aio(struct inode *inode, struct iov_iter *from, loff_t pos) |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 114 | { |
| 115 | struct super_block *sb = inode->i_sb; |
| 116 | int blockmask = sb->s_blocksize - 1; |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 117 | |
Theodore Ts'o | 6e6358f | 2014-04-12 12:45:25 -0400 | [diff] [blame] | 118 | if (pos >= i_size_read(inode)) |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 119 | return 0; |
| 120 | |
Al Viro | 9b88416 | 2014-04-17 16:09:22 -0400 | [diff] [blame] | 121 | if ((pos | iov_iter_alignment(from)) & blockmask) |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 122 | return 1; |
| 123 | |
| 124 | return 0; |
| 125 | } |
| 126 | |
Jan Kara | 213bcd9 | 2016-11-20 17:29:51 -0500 | [diff] [blame] | 127 | /* Is IO overwriting allocated and initialized blocks? */ |
| 128 | static bool ext4_overwrite_io(struct inode *inode, loff_t pos, loff_t len) |
| 129 | { |
| 130 | struct ext4_map_blocks map; |
| 131 | unsigned int blkbits = inode->i_blkbits; |
| 132 | int err, blklen; |
| 133 | |
| 134 | if (pos + len > i_size_read(inode)) |
| 135 | return false; |
| 136 | |
| 137 | map.m_lblk = pos >> blkbits; |
| 138 | map.m_len = EXT4_MAX_BLOCKS(len, pos, blkbits); |
| 139 | blklen = map.m_len; |
| 140 | |
| 141 | err = ext4_map_blocks(NULL, inode, &map, 0); |
| 142 | /* |
| 143 | * 'err==len' means that all of the blocks have been preallocated, |
| 144 | * regardless of whether they have been initialized or not. To exclude |
| 145 | * unwritten extents, we need to check m_flags. |
| 146 | */ |
| 147 | return err == blklen && (map.m_flags & EXT4_MAP_MAPPED); |
| 148 | } |
| 149 | |
| 150 | static ssize_t ext4_write_checks(struct kiocb *iocb, struct iov_iter *from) |
| 151 | { |
| 152 | struct inode *inode = file_inode(iocb->ki_filp); |
| 153 | ssize_t ret; |
| 154 | |
| 155 | ret = generic_write_checks(iocb, from); |
| 156 | if (ret <= 0) |
| 157 | return ret; |
| 158 | /* |
| 159 | * If we have encountered a bitmap-format file, the size limit |
| 160 | * is smaller than s_maxbytes, which is for extent-mapped files. |
| 161 | */ |
| 162 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) { |
| 163 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 164 | |
| 165 | if (iocb->ki_pos >= sbi->s_bitmap_maxbytes) |
| 166 | return -EFBIG; |
| 167 | iov_iter_truncate(from, sbi->s_bitmap_maxbytes - iocb->ki_pos); |
| 168 | } |
| 169 | return iov_iter_count(from); |
| 170 | } |
| 171 | |
Jan Kara | 776722e | 2016-11-20 18:09:11 -0500 | [diff] [blame] | 172 | #ifdef CONFIG_FS_DAX |
| 173 | static ssize_t |
| 174 | ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from) |
| 175 | { |
| 176 | struct inode *inode = file_inode(iocb->ki_filp); |
| 177 | ssize_t ret; |
| 178 | bool overwrite = false; |
| 179 | |
| 180 | inode_lock(inode); |
| 181 | ret = ext4_write_checks(iocb, from); |
| 182 | if (ret <= 0) |
| 183 | goto out; |
| 184 | ret = file_remove_privs(iocb->ki_filp); |
| 185 | if (ret) |
| 186 | goto out; |
| 187 | ret = file_update_time(iocb->ki_filp); |
| 188 | if (ret) |
| 189 | goto out; |
| 190 | |
| 191 | if (ext4_overwrite_io(inode, iocb->ki_pos, iov_iter_count(from))) { |
| 192 | overwrite = true; |
| 193 | downgrade_write(&inode->i_rwsem); |
| 194 | } |
| 195 | ret = dax_iomap_rw(iocb, from, &ext4_iomap_ops); |
| 196 | out: |
| 197 | if (!overwrite) |
| 198 | inode_unlock(inode); |
| 199 | else |
| 200 | inode_unlock_shared(inode); |
| 201 | if (ret > 0) |
| 202 | ret = generic_write_sync(iocb, ret); |
| 203 | return ret; |
| 204 | } |
| 205 | #endif |
| 206 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 207 | static ssize_t |
Al Viro | 9b88416 | 2014-04-17 16:09:22 -0400 | [diff] [blame] | 208 | ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 209 | { |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 210 | struct inode *inode = file_inode(iocb->ki_filp); |
Al Viro | 2ba48ce | 2015-04-09 13:52:01 -0400 | [diff] [blame] | 211 | int o_direct = iocb->ki_flags & IOCB_DIRECT; |
Jan Kara | e142d05 | 2016-03-08 22:44:50 -0500 | [diff] [blame] | 212 | int unaligned_aio = 0; |
Theodore Ts'o | 8ad2850 | 2014-04-21 14:26:57 -0400 | [diff] [blame] | 213 | int overwrite = 0; |
Zheng Liu | 8563000 | 2012-05-28 18:06:51 -0400 | [diff] [blame] | 214 | ssize_t ret; |
Theodore Ts'o | 7608e61 | 2014-04-21 14:26:28 -0400 | [diff] [blame] | 215 | |
Jan Kara | 776722e | 2016-11-20 18:09:11 -0500 | [diff] [blame] | 216 | #ifdef CONFIG_FS_DAX |
| 217 | if (IS_DAX(inode)) |
| 218 | return ext4_dax_write_iter(iocb, from); |
| 219 | #endif |
| 220 | |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 221 | inode_lock(inode); |
Jan Kara | 213bcd9 | 2016-11-20 17:29:51 -0500 | [diff] [blame] | 222 | ret = ext4_write_checks(iocb, from); |
Al Viro | 3309dd0 | 2015-04-09 12:55:47 -0400 | [diff] [blame] | 223 | if (ret <= 0) |
Al Viro | e768d7f | 2015-04-07 14:48:22 -0400 | [diff] [blame] | 224 | goto out; |
Theodore Ts'o | f5ccfe1 | 2014-04-21 14:37:52 -0400 | [diff] [blame] | 225 | |
| 226 | /* |
Jan Kara | e142d05 | 2016-03-08 22:44:50 -0500 | [diff] [blame] | 227 | * Unaligned direct AIO must be serialized among each other as zeroing |
| 228 | * of partial blocks of two competing unaligned AIOs can result in data |
| 229 | * corruption. |
| 230 | */ |
| 231 | if (o_direct && ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) && |
| 232 | !is_sync_kiocb(iocb) && |
| 233 | ext4_unaligned_aio(inode, from, iocb->ki_pos)) { |
| 234 | unaligned_aio = 1; |
| 235 | ext4_unwritten_wait(inode); |
| 236 | } |
| 237 | |
Dmitry Monakhov | a41537e | 2014-10-30 10:53:16 -0400 | [diff] [blame] | 238 | iocb->private = &overwrite; |
Jan Kara | 213bcd9 | 2016-11-20 17:29:51 -0500 | [diff] [blame] | 239 | /* Check whether we do a DIO overwrite or not */ |
| 240 | if (o_direct && ext4_should_dioread_nolock(inode) && !unaligned_aio && |
| 241 | ext4_overwrite_io(inode, iocb->ki_pos, iov_iter_count(from))) |
| 242 | overwrite = 1; |
Theodore Ts'o | 8ad2850 | 2014-04-21 14:26:57 -0400 | [diff] [blame] | 243 | |
Al Viro | 9b88416 | 2014-04-17 16:09:22 -0400 | [diff] [blame] | 244 | ret = __generic_file_write_iter(iocb, from); |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 245 | inode_unlock(inode); |
Theodore Ts'o | 8ad2850 | 2014-04-21 14:26:57 -0400 | [diff] [blame] | 246 | |
Christoph Hellwig | e259221 | 2016-04-07 08:52:01 -0700 | [diff] [blame] | 247 | if (ret > 0) |
| 248 | ret = generic_write_sync(iocb, ret); |
Theodore Ts'o | 8ad2850 | 2014-04-21 14:26:57 -0400 | [diff] [blame] | 249 | |
Al Viro | e768d7f | 2015-04-07 14:48:22 -0400 | [diff] [blame] | 250 | return ret; |
| 251 | |
| 252 | out: |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 253 | inode_unlock(inode); |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 254 | return ret; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 255 | } |
| 256 | |
Ross Zwisler | 923ae0f | 2015-02-16 15:59:38 -0800 | [diff] [blame] | 257 | #ifdef CONFIG_FS_DAX |
| 258 | static int ext4_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
| 259 | { |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 260 | int result; |
| 261 | handle_t *handle = NULL; |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 262 | struct inode *inode = file_inode(vma->vm_file); |
| 263 | struct super_block *sb = inode->i_sb; |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 264 | bool write = vmf->flags & FAULT_FLAG_WRITE; |
| 265 | |
| 266 | if (write) { |
| 267 | sb_start_pagefault(sb); |
| 268 | file_update_time(vma->vm_file); |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 269 | down_read(&EXT4_I(inode)->i_mmap_sem); |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 270 | handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE, |
| 271 | EXT4_DATA_TRANS_BLOCKS(sb)); |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 272 | } else |
| 273 | down_read(&EXT4_I(inode)->i_mmap_sem); |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 274 | |
| 275 | if (IS_ERR(handle)) |
| 276 | result = VM_FAULT_SIGBUS; |
| 277 | else |
Jan Kara | e2ae766 | 2016-11-20 18:51:24 -0500 | [diff] [blame] | 278 | result = dax_iomap_fault(vma, vmf, &ext4_iomap_ops); |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 279 | |
| 280 | if (write) { |
| 281 | if (!IS_ERR(handle)) |
| 282 | ext4_journal_stop(handle); |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 283 | up_read(&EXT4_I(inode)->i_mmap_sem); |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 284 | sb_end_pagefault(sb); |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 285 | } else |
| 286 | up_read(&EXT4_I(inode)->i_mmap_sem); |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 287 | |
| 288 | return result; |
Ross Zwisler | 923ae0f | 2015-02-16 15:59:38 -0800 | [diff] [blame] | 289 | } |
| 290 | |
Matthew Wilcox | 11bd1a9 | 2015-09-08 14:59:03 -0700 | [diff] [blame] | 291 | static int ext4_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr, |
| 292 | pmd_t *pmd, unsigned int flags) |
| 293 | { |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 294 | int result; |
| 295 | handle_t *handle = NULL; |
| 296 | struct inode *inode = file_inode(vma->vm_file); |
| 297 | struct super_block *sb = inode->i_sb; |
| 298 | bool write = flags & FAULT_FLAG_WRITE; |
| 299 | |
| 300 | if (write) { |
| 301 | sb_start_pagefault(sb); |
| 302 | file_update_time(vma->vm_file); |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 303 | down_read(&EXT4_I(inode)->i_mmap_sem); |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 304 | handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE, |
| 305 | ext4_chunk_trans_blocks(inode, |
| 306 | PMD_SIZE / PAGE_SIZE)); |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 307 | } else |
| 308 | down_read(&EXT4_I(inode)->i_mmap_sem); |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 309 | |
| 310 | if (IS_ERR(handle)) |
| 311 | result = VM_FAULT_SIGBUS; |
Jan Kara | e2ae766 | 2016-11-20 18:51:24 -0500 | [diff] [blame] | 312 | else { |
| 313 | result = dax_iomap_pmd_fault(vma, addr, pmd, flags, |
| 314 | &ext4_iomap_ops); |
| 315 | } |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 316 | |
| 317 | if (write) { |
| 318 | if (!IS_ERR(handle)) |
| 319 | ext4_journal_stop(handle); |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 320 | up_read(&EXT4_I(inode)->i_mmap_sem); |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 321 | sb_end_pagefault(sb); |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 322 | } else |
| 323 | up_read(&EXT4_I(inode)->i_mmap_sem); |
Matthew Wilcox | 01a33b4 | 2015-09-08 14:59:22 -0700 | [diff] [blame] | 324 | |
| 325 | return result; |
Matthew Wilcox | 11bd1a9 | 2015-09-08 14:59:03 -0700 | [diff] [blame] | 326 | } |
| 327 | |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 328 | /* |
Ross Zwisler | 1e9d180 | 2016-02-27 14:01:13 -0500 | [diff] [blame] | 329 | * Handle write fault for VM_MIXEDMAP mappings. Similarly to ext4_dax_fault() |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 330 | * handler we check for races agaist truncate. Note that since we cycle through |
| 331 | * i_mmap_sem, we are sure that also any hole punching that began before we |
| 332 | * were called is finished by now and so if it included part of the file we |
| 333 | * are working on, our pte will get unmapped and the check for pte_same() in |
| 334 | * wp_pfn_shared() fails. Thus fault gets retried and things work out as |
| 335 | * desired. |
| 336 | */ |
| 337 | static int ext4_dax_pfn_mkwrite(struct vm_area_struct *vma, |
| 338 | struct vm_fault *vmf) |
| 339 | { |
| 340 | struct inode *inode = file_inode(vma->vm_file); |
| 341 | struct super_block *sb = inode->i_sb; |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 342 | loff_t size; |
Ross Zwisler | d5be7a0 | 2016-01-22 15:10:53 -0800 | [diff] [blame] | 343 | int ret; |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 344 | |
| 345 | sb_start_pagefault(sb); |
| 346 | file_update_time(vma->vm_file); |
| 347 | down_read(&EXT4_I(inode)->i_mmap_sem); |
| 348 | size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT; |
| 349 | if (vmf->pgoff >= size) |
| 350 | ret = VM_FAULT_SIGBUS; |
Ross Zwisler | d5be7a0 | 2016-01-22 15:10:53 -0800 | [diff] [blame] | 351 | else |
| 352 | ret = dax_pfn_mkwrite(vma, vmf); |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 353 | up_read(&EXT4_I(inode)->i_mmap_sem); |
| 354 | sb_end_pagefault(sb); |
| 355 | |
| 356 | return ret; |
Ross Zwisler | 923ae0f | 2015-02-16 15:59:38 -0800 | [diff] [blame] | 357 | } |
| 358 | |
| 359 | static const struct vm_operations_struct ext4_dax_vm_ops = { |
| 360 | .fault = ext4_dax_fault, |
Matthew Wilcox | 11bd1a9 | 2015-09-08 14:59:03 -0700 | [diff] [blame] | 361 | .pmd_fault = ext4_dax_pmd_fault, |
Ross Zwisler | 1e9d180 | 2016-02-27 14:01:13 -0500 | [diff] [blame] | 362 | .page_mkwrite = ext4_dax_fault, |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 363 | .pfn_mkwrite = ext4_dax_pfn_mkwrite, |
Ross Zwisler | 923ae0f | 2015-02-16 15:59:38 -0800 | [diff] [blame] | 364 | }; |
| 365 | #else |
| 366 | #define ext4_dax_vm_ops ext4_file_vm_ops |
| 367 | #endif |
| 368 | |
Alexey Dobriyan | f0f37e2 | 2009-09-27 22:29:37 +0400 | [diff] [blame] | 369 | static const struct vm_operations_struct ext4_file_vm_ops = { |
Jan Kara | ea3d720 | 2015-12-07 14:28:03 -0500 | [diff] [blame] | 370 | .fault = ext4_filemap_fault, |
Kirill A. Shutemov | f182036 | 2014-04-07 15:37:19 -0700 | [diff] [blame] | 371 | .map_pages = filemap_map_pages, |
Aneesh Kumar K.V | 2e9ee85 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 372 | .page_mkwrite = ext4_page_mkwrite, |
| 373 | }; |
| 374 | |
| 375 | static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma) |
| 376 | { |
Michael Halcrow | c9c7429 | 2015-04-12 00:56:10 -0400 | [diff] [blame] | 377 | struct inode *inode = file->f_mapping->host; |
| 378 | |
| 379 | if (ext4_encrypted_inode(inode)) { |
Jaegeuk Kim | a7550b3 | 2016-07-10 14:01:03 -0400 | [diff] [blame] | 380 | int err = fscrypt_get_encryption_info(inode); |
Michael Halcrow | c9c7429 | 2015-04-12 00:56:10 -0400 | [diff] [blame] | 381 | if (err) |
| 382 | return 0; |
Jaegeuk Kim | a7550b3 | 2016-07-10 14:01:03 -0400 | [diff] [blame] | 383 | if (!fscrypt_has_encryption_key(inode)) |
Theodore Ts'o | abdd438 | 2015-05-31 13:35:39 -0400 | [diff] [blame] | 384 | return -ENOKEY; |
Michael Halcrow | c9c7429 | 2015-04-12 00:56:10 -0400 | [diff] [blame] | 385 | } |
Aneesh Kumar K.V | 2e9ee85 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 386 | file_accessed(file); |
Ross Zwisler | 923ae0f | 2015-02-16 15:59:38 -0800 | [diff] [blame] | 387 | if (IS_DAX(file_inode(file))) { |
| 388 | vma->vm_ops = &ext4_dax_vm_ops; |
Matthew Wilcox | 11bd1a9 | 2015-09-08 14:59:03 -0700 | [diff] [blame] | 389 | vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE; |
Ross Zwisler | 923ae0f | 2015-02-16 15:59:38 -0800 | [diff] [blame] | 390 | } else { |
| 391 | vma->vm_ops = &ext4_file_vm_ops; |
| 392 | } |
Aneesh Kumar K.V | 2e9ee85 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 393 | return 0; |
| 394 | } |
| 395 | |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 396 | static int ext4_file_open(struct inode * inode, struct file * filp) |
| 397 | { |
| 398 | struct super_block *sb = inode->i_sb; |
| 399 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 400 | struct vfsmount *mnt = filp->f_path.mnt; |
Miklos Szeredi | 9dd78d8 | 2016-03-26 16:14:41 -0400 | [diff] [blame] | 401 | struct dentry *dir; |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 402 | struct path path; |
| 403 | char buf[64], *cp; |
Michael Halcrow | c9c7429 | 2015-04-12 00:56:10 -0400 | [diff] [blame] | 404 | int ret; |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 405 | |
| 406 | if (unlikely(!(sbi->s_mount_flags & EXT4_MF_MNTDIR_SAMPLED) && |
| 407 | !(sb->s_flags & MS_RDONLY))) { |
| 408 | sbi->s_mount_flags |= EXT4_MF_MNTDIR_SAMPLED; |
| 409 | /* |
| 410 | * Sample where the filesystem has been mounted and |
| 411 | * store it in the superblock for sysadmin convenience |
| 412 | * when trying to sort through large numbers of block |
| 413 | * devices or filesystem images. |
| 414 | */ |
| 415 | memset(buf, 0, sizeof(buf)); |
Al Viro | 3899167 | 2010-01-23 20:10:29 -0500 | [diff] [blame] | 416 | path.mnt = mnt; |
| 417 | path.dentry = mnt->mnt_root; |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 418 | cp = d_path(&path, buf, sizeof(buf)); |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 419 | if (!IS_ERR(cp)) { |
Jan Kara | 044ce47 | 2012-07-22 20:31:31 -0400 | [diff] [blame] | 420 | handle_t *handle; |
| 421 | int err; |
| 422 | |
Theodore Ts'o | 9924a92 | 2013-02-08 21:59:22 -0500 | [diff] [blame] | 423 | handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1); |
Jan Kara | 044ce47 | 2012-07-22 20:31:31 -0400 | [diff] [blame] | 424 | if (IS_ERR(handle)) |
| 425 | return PTR_ERR(handle); |
liang xie | 5d60125 | 2014-05-12 22:06:43 -0400 | [diff] [blame] | 426 | BUFFER_TRACE(sbi->s_sbh, "get_write_access"); |
Jan Kara | 044ce47 | 2012-07-22 20:31:31 -0400 | [diff] [blame] | 427 | err = ext4_journal_get_write_access(handle, sbi->s_sbh); |
| 428 | if (err) { |
| 429 | ext4_journal_stop(handle); |
| 430 | return err; |
| 431 | } |
Darrick J. Wong | cf80390 | 2011-10-25 09:18:41 -0400 | [diff] [blame] | 432 | strlcpy(sbi->s_es->s_last_mounted, cp, |
| 433 | sizeof(sbi->s_es->s_last_mounted)); |
Jan Kara | 044ce47 | 2012-07-22 20:31:31 -0400 | [diff] [blame] | 434 | ext4_handle_dirty_super(handle, sb); |
| 435 | ext4_journal_stop(handle); |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 436 | } |
| 437 | } |
Theodore Ts'o | abdd438 | 2015-05-31 13:35:39 -0400 | [diff] [blame] | 438 | if (ext4_encrypted_inode(inode)) { |
Jaegeuk Kim | a7550b3 | 2016-07-10 14:01:03 -0400 | [diff] [blame] | 439 | ret = fscrypt_get_encryption_info(inode); |
Theodore Ts'o | abdd438 | 2015-05-31 13:35:39 -0400 | [diff] [blame] | 440 | if (ret) |
| 441 | return -EACCES; |
Jaegeuk Kim | a7550b3 | 2016-07-10 14:01:03 -0400 | [diff] [blame] | 442 | if (!fscrypt_has_encryption_key(inode)) |
Theodore Ts'o | abdd438 | 2015-05-31 13:35:39 -0400 | [diff] [blame] | 443 | return -ENOKEY; |
| 444 | } |
Miklos Szeredi | 9dd78d8 | 2016-03-26 16:14:41 -0400 | [diff] [blame] | 445 | |
Miklos Szeredi | c0a37d487 | 2016-03-26 16:14:42 -0400 | [diff] [blame] | 446 | dir = dget_parent(file_dentry(filp)); |
Miklos Szeredi | 9dd78d8 | 2016-03-26 16:14:41 -0400 | [diff] [blame] | 447 | if (ext4_encrypted_inode(d_inode(dir)) && |
Jaegeuk Kim | a7550b3 | 2016-07-10 14:01:03 -0400 | [diff] [blame] | 448 | !fscrypt_has_permitted_context(d_inode(dir), inode)) { |
Theodore Ts'o | ff978b0 | 2016-02-08 00:54:26 -0500 | [diff] [blame] | 449 | ext4_warning(inode->i_sb, |
Jakub Wilk | 8d2ae1c | 2016-04-27 01:11:21 -0400 | [diff] [blame] | 450 | "Inconsistent encryption contexts: %lu/%lu", |
Miklos Szeredi | 9dd78d8 | 2016-03-26 16:14:41 -0400 | [diff] [blame] | 451 | (unsigned long) d_inode(dir)->i_ino, |
Theodore Ts'o | ff978b0 | 2016-02-08 00:54:26 -0500 | [diff] [blame] | 452 | (unsigned long) inode->i_ino); |
Miklos Szeredi | 9dd78d8 | 2016-03-26 16:14:41 -0400 | [diff] [blame] | 453 | dput(dir); |
Theodore Ts'o | ff978b0 | 2016-02-08 00:54:26 -0500 | [diff] [blame] | 454 | return -EPERM; |
| 455 | } |
Miklos Szeredi | 9dd78d8 | 2016-03-26 16:14:41 -0400 | [diff] [blame] | 456 | dput(dir); |
Theodore Ts'o | 8aefcd5 | 2011-01-10 12:29:43 -0500 | [diff] [blame] | 457 | /* |
| 458 | * Set up the jbd2_inode if we are opening the inode for |
| 459 | * writing and the journal is present |
| 460 | */ |
Jan Kara | a361293 | 2013-08-16 21:19:41 -0400 | [diff] [blame] | 461 | if (filp->f_mode & FMODE_WRITE) { |
Michael Halcrow | c9c7429 | 2015-04-12 00:56:10 -0400 | [diff] [blame] | 462 | ret = ext4_inode_attach_jinode(inode); |
Jan Kara | a361293 | 2013-08-16 21:19:41 -0400 | [diff] [blame] | 463 | if (ret < 0) |
| 464 | return ret; |
Theodore Ts'o | 8aefcd5 | 2011-01-10 12:29:43 -0500 | [diff] [blame] | 465 | } |
Theodore Ts'o | abdd438 | 2015-05-31 13:35:39 -0400 | [diff] [blame] | 466 | return dquot_file_open(inode, filp); |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 467 | } |
| 468 | |
Toshiyuki Okajima | e0d10bf | 2010-10-27 21:30:06 -0400 | [diff] [blame] | 469 | /* |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 470 | * Here we use ext4_map_blocks() to get a block mapping for a extent-based |
| 471 | * file rather than ext4_ext_walk_space() because we can introduce |
| 472 | * SEEK_DATA/SEEK_HOLE for block-mapped and extent-mapped file at the same |
| 473 | * function. When extent status tree has been fully implemented, it will |
| 474 | * track all extent status for a file and we can directly use it to |
| 475 | * retrieve the offset for SEEK_DATA/SEEK_HOLE. |
| 476 | */ |
| 477 | |
| 478 | /* |
| 479 | * When we retrieve the offset for SEEK_DATA/SEEK_HOLE, we would need to |
| 480 | * lookup page cache to check whether or not there has some data between |
| 481 | * [startoff, endoff] because, if this range contains an unwritten extent, |
| 482 | * we determine this extent as a data or a hole according to whether the |
| 483 | * page cache has data or not. |
| 484 | */ |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 485 | static int ext4_find_unwritten_pgoff(struct inode *inode, |
| 486 | int whence, |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 487 | ext4_lblk_t end_blk, |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 488 | loff_t *offset) |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 489 | { |
| 490 | struct pagevec pvec; |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 491 | unsigned int blkbits; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 492 | pgoff_t index; |
| 493 | pgoff_t end; |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 494 | loff_t endoff; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 495 | loff_t startoff; |
| 496 | loff_t lastoff; |
| 497 | int found = 0; |
| 498 | |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 499 | blkbits = inode->i_sb->s_blocksize_bits; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 500 | startoff = *offset; |
| 501 | lastoff = startoff; |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 502 | endoff = (loff_t)end_blk << blkbits; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 503 | |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 504 | index = startoff >> PAGE_SHIFT; |
| 505 | end = endoff >> PAGE_SHIFT; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 506 | |
| 507 | pagevec_init(&pvec, 0); |
| 508 | do { |
| 509 | int i, num; |
| 510 | unsigned long nr_pages; |
| 511 | |
| 512 | num = min_t(pgoff_t, end - index, PAGEVEC_SIZE); |
| 513 | nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index, |
| 514 | (pgoff_t)num); |
| 515 | if (nr_pages == 0) { |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 516 | if (whence == SEEK_DATA) |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 517 | break; |
| 518 | |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 519 | BUG_ON(whence != SEEK_HOLE); |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 520 | /* |
| 521 | * If this is the first time to go into the loop and |
| 522 | * offset is not beyond the end offset, it will be a |
| 523 | * hole at this offset |
| 524 | */ |
| 525 | if (lastoff == startoff || lastoff < endoff) |
| 526 | found = 1; |
| 527 | break; |
| 528 | } |
| 529 | |
| 530 | /* |
| 531 | * If this is the first time to go into the loop and |
| 532 | * offset is smaller than the first page offset, it will be a |
| 533 | * hole at this offset. |
| 534 | */ |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 535 | if (lastoff == startoff && whence == SEEK_HOLE && |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 536 | lastoff < page_offset(pvec.pages[0])) { |
| 537 | found = 1; |
| 538 | break; |
| 539 | } |
| 540 | |
| 541 | for (i = 0; i < nr_pages; i++) { |
| 542 | struct page *page = pvec.pages[i]; |
| 543 | struct buffer_head *bh, *head; |
| 544 | |
| 545 | /* |
| 546 | * If the current offset is not beyond the end of given |
| 547 | * range, it will be a hole. |
| 548 | */ |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 549 | if (lastoff < endoff && whence == SEEK_HOLE && |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 550 | page->index > end) { |
| 551 | found = 1; |
| 552 | *offset = lastoff; |
| 553 | goto out; |
| 554 | } |
| 555 | |
| 556 | lock_page(page); |
| 557 | |
| 558 | if (unlikely(page->mapping != inode->i_mapping)) { |
| 559 | unlock_page(page); |
| 560 | continue; |
| 561 | } |
| 562 | |
| 563 | if (!page_has_buffers(page)) { |
| 564 | unlock_page(page); |
| 565 | continue; |
| 566 | } |
| 567 | |
| 568 | if (page_has_buffers(page)) { |
| 569 | lastoff = page_offset(page); |
| 570 | bh = head = page_buffers(page); |
| 571 | do { |
| 572 | if (buffer_uptodate(bh) || |
| 573 | buffer_unwritten(bh)) { |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 574 | if (whence == SEEK_DATA) |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 575 | found = 1; |
| 576 | } else { |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 577 | if (whence == SEEK_HOLE) |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 578 | found = 1; |
| 579 | } |
| 580 | if (found) { |
| 581 | *offset = max_t(loff_t, |
| 582 | startoff, lastoff); |
| 583 | unlock_page(page); |
| 584 | goto out; |
| 585 | } |
| 586 | lastoff += bh->b_size; |
| 587 | bh = bh->b_this_page; |
| 588 | } while (bh != head); |
| 589 | } |
| 590 | |
| 591 | lastoff = page_offset(page) + PAGE_SIZE; |
| 592 | unlock_page(page); |
| 593 | } |
| 594 | |
| 595 | /* |
| 596 | * The no. of pages is less than our desired, that would be a |
| 597 | * hole in there. |
| 598 | */ |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 599 | if (nr_pages < num && whence == SEEK_HOLE) { |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 600 | found = 1; |
| 601 | *offset = lastoff; |
| 602 | break; |
| 603 | } |
| 604 | |
| 605 | index = pvec.pages[i - 1]->index + 1; |
| 606 | pagevec_release(&pvec); |
| 607 | } while (index <= end); |
| 608 | |
| 609 | out: |
| 610 | pagevec_release(&pvec); |
| 611 | return found; |
| 612 | } |
| 613 | |
| 614 | /* |
| 615 | * ext4_seek_data() retrieves the offset for SEEK_DATA. |
| 616 | */ |
| 617 | static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize) |
| 618 | { |
| 619 | struct inode *inode = file->f_mapping->host; |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 620 | struct extent_status es; |
| 621 | ext4_lblk_t start, last, end; |
| 622 | loff_t dataoff, isize; |
| 623 | int blkbits; |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 624 | int ret; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 625 | |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 626 | inode_lock(inode); |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 627 | |
| 628 | isize = i_size_read(inode); |
| 629 | if (offset >= isize) { |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 630 | inode_unlock(inode); |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 631 | return -ENXIO; |
| 632 | } |
| 633 | |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 634 | blkbits = inode->i_sb->s_blocksize_bits; |
| 635 | start = offset >> blkbits; |
| 636 | last = start; |
| 637 | end = isize >> blkbits; |
| 638 | dataoff = offset; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 639 | |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 640 | do { |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 641 | ret = ext4_get_next_extent(inode, last, end - last + 1, &es); |
| 642 | if (ret <= 0) { |
| 643 | /* No extent found -> no data */ |
| 644 | if (ret == 0) |
| 645 | ret = -ENXIO; |
| 646 | inode_unlock(inode); |
| 647 | return ret; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 648 | } |
| 649 | |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 650 | last = es.es_lblk; |
| 651 | if (last != start) |
| 652 | dataoff = (loff_t)last << blkbits; |
| 653 | if (!ext4_es_is_unwritten(&es)) |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 654 | break; |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 655 | |
| 656 | /* |
| 657 | * If there is a unwritten extent at this offset, |
| 658 | * it will be as a data or a hole according to page |
| 659 | * cache that has data or not. |
| 660 | */ |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 661 | if (ext4_find_unwritten_pgoff(inode, SEEK_DATA, |
| 662 | es.es_lblk + es.es_len, &dataoff)) |
| 663 | break; |
| 664 | last += es.es_len; |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 665 | dataoff = (loff_t)last << blkbits; |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 666 | cond_resched(); |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 667 | } while (last <= end); |
| 668 | |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 669 | inode_unlock(inode); |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 670 | |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 671 | if (dataoff > isize) |
| 672 | return -ENXIO; |
| 673 | |
| 674 | return vfs_setpos(file, dataoff, maxsize); |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 675 | } |
| 676 | |
| 677 | /* |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 678 | * ext4_seek_hole() retrieves the offset for SEEK_HOLE. |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 679 | */ |
| 680 | static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize) |
| 681 | { |
| 682 | struct inode *inode = file->f_mapping->host; |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 683 | struct extent_status es; |
| 684 | ext4_lblk_t start, last, end; |
| 685 | loff_t holeoff, isize; |
| 686 | int blkbits; |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 687 | int ret; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 688 | |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 689 | inode_lock(inode); |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 690 | |
| 691 | isize = i_size_read(inode); |
| 692 | if (offset >= isize) { |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 693 | inode_unlock(inode); |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 694 | return -ENXIO; |
| 695 | } |
| 696 | |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 697 | blkbits = inode->i_sb->s_blocksize_bits; |
| 698 | start = offset >> blkbits; |
| 699 | last = start; |
| 700 | end = isize >> blkbits; |
| 701 | holeoff = offset; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 702 | |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 703 | do { |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 704 | ret = ext4_get_next_extent(inode, last, end - last + 1, &es); |
| 705 | if (ret < 0) { |
| 706 | inode_unlock(inode); |
| 707 | return ret; |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 708 | } |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 709 | /* Found a hole? */ |
| 710 | if (ret == 0 || es.es_lblk > last) { |
| 711 | if (last != start) |
| 712 | holeoff = (loff_t)last << blkbits; |
| 713 | break; |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 714 | } |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 715 | /* |
| 716 | * If there is a unwritten extent at this offset, |
| 717 | * it will be as a data or a hole according to page |
| 718 | * cache that has data or not. |
| 719 | */ |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 720 | if (ext4_es_is_unwritten(&es) && |
| 721 | ext4_find_unwritten_pgoff(inode, SEEK_HOLE, |
| 722 | last + es.es_len, &holeoff)) |
| 723 | break; |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 724 | |
Jan Kara | 2d90c16 | 2016-03-09 23:11:13 -0500 | [diff] [blame] | 725 | last += es.es_len; |
| 726 | holeoff = (loff_t)last << blkbits; |
| 727 | cond_resched(); |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 728 | } while (last <= end); |
| 729 | |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 730 | inode_unlock(inode); |
Theodore Ts'o | ad7fefb | 2015-01-02 15:16:00 -0500 | [diff] [blame] | 731 | |
| 732 | if (holeoff > isize) |
| 733 | holeoff = isize; |
| 734 | |
| 735 | return vfs_setpos(file, holeoff, maxsize); |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 736 | } |
| 737 | |
| 738 | /* |
Eric Sandeen | ec7268c | 2012-04-30 13:14:03 -0500 | [diff] [blame] | 739 | * ext4_llseek() handles both block-mapped and extent-mapped maxbytes values |
| 740 | * by calling generic_file_llseek_size() with the appropriate maxbytes |
| 741 | * value for each. |
Toshiyuki Okajima | e0d10bf | 2010-10-27 21:30:06 -0400 | [diff] [blame] | 742 | */ |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 743 | loff_t ext4_llseek(struct file *file, loff_t offset, int whence) |
Toshiyuki Okajima | e0d10bf | 2010-10-27 21:30:06 -0400 | [diff] [blame] | 744 | { |
| 745 | struct inode *inode = file->f_mapping->host; |
| 746 | loff_t maxbytes; |
| 747 | |
| 748 | if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
| 749 | maxbytes = EXT4_SB(inode->i_sb)->s_bitmap_maxbytes; |
| 750 | else |
| 751 | maxbytes = inode->i_sb->s_maxbytes; |
Toshiyuki Okajima | e0d10bf | 2010-10-27 21:30:06 -0400 | [diff] [blame] | 752 | |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 753 | switch (whence) { |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 754 | case SEEK_SET: |
| 755 | case SEEK_CUR: |
| 756 | case SEEK_END: |
Andrew Morton | 965c8e5 | 2012-12-17 15:59:39 -0800 | [diff] [blame] | 757 | return generic_file_llseek_size(file, offset, whence, |
Zheng Liu | c8c0df2 | 2012-11-08 21:57:40 -0500 | [diff] [blame] | 758 | maxbytes, i_size_read(inode)); |
| 759 | case SEEK_DATA: |
| 760 | return ext4_seek_data(file, offset, maxbytes); |
| 761 | case SEEK_HOLE: |
| 762 | return ext4_seek_hole(file, offset, maxbytes); |
| 763 | } |
| 764 | |
| 765 | return -EINVAL; |
Toshiyuki Okajima | e0d10bf | 2010-10-27 21:30:06 -0400 | [diff] [blame] | 766 | } |
| 767 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 768 | const struct file_operations ext4_file_operations = { |
Toshiyuki Okajima | e0d10bf | 2010-10-27 21:30:06 -0400 | [diff] [blame] | 769 | .llseek = ext4_llseek, |
Jan Kara | 364443c | 2016-11-20 17:36:06 -0500 | [diff] [blame] | 770 | .read_iter = ext4_file_read_iter, |
Al Viro | 9b88416 | 2014-04-17 16:09:22 -0400 | [diff] [blame] | 771 | .write_iter = ext4_file_write_iter, |
Andi Kleen | 5cdd7b2 | 2008-04-29 22:03:54 -0400 | [diff] [blame] | 772 | .unlocked_ioctl = ext4_ioctl, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 773 | #ifdef CONFIG_COMPAT |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 774 | .compat_ioctl = ext4_compat_ioctl, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 775 | #endif |
Aneesh Kumar K.V | 2e9ee85 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 776 | .mmap = ext4_file_mmap, |
Theodore Ts'o | bc0b0d6 | 2009-06-13 10:09:48 -0400 | [diff] [blame] | 777 | .open = ext4_file_open, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 778 | .release = ext4_release_file, |
| 779 | .fsync = ext4_sync_file, |
Toshi Kani | dbe6ec8 | 2016-10-07 16:59:59 -0700 | [diff] [blame] | 780 | .get_unmapped_area = thp_get_unmapped_area, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 781 | .splice_read = generic_file_splice_read, |
Al Viro | 8d02076 | 2014-04-05 04:27:08 -0400 | [diff] [blame] | 782 | .splice_write = iter_file_splice_write, |
Christoph Hellwig | 2fe17c1 | 2011-01-14 13:07:43 +0100 | [diff] [blame] | 783 | .fallocate = ext4_fallocate, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 784 | }; |
| 785 | |
Arjan van de Ven | 754661f | 2007-02-12 00:55:38 -0800 | [diff] [blame] | 786 | const struct inode_operations ext4_file_inode_operations = { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 787 | .setattr = ext4_setattr, |
Mingming Cao | 3e3398a | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 788 | .getattr = ext4_getattr, |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 789 | .listxattr = ext4_listxattr, |
Christoph Hellwig | 4e34e71 | 2011-07-23 17:37:31 +0200 | [diff] [blame] | 790 | .get_acl = ext4_get_acl, |
Christoph Hellwig | 64e178a | 2013-12-20 05:16:44 -0800 | [diff] [blame] | 791 | .set_acl = ext4_set_acl, |
Eric Sandeen | 6873fa0 | 2008-10-07 00:46:36 -0400 | [diff] [blame] | 792 | .fiemap = ext4_fiemap, |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 793 | }; |
| 794 | |