Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/ext4/page-io.c |
| 3 | * |
| 4 | * This contains the new page_io functions for ext4 |
| 5 | * |
| 6 | * Written by Theodore Ts'o, 2010. |
| 7 | */ |
| 8 | |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 9 | #include <linux/fs.h> |
| 10 | #include <linux/time.h> |
| 11 | #include <linux/jbd2.h> |
| 12 | #include <linux/highuid.h> |
| 13 | #include <linux/pagemap.h> |
| 14 | #include <linux/quotaops.h> |
| 15 | #include <linux/string.h> |
| 16 | #include <linux/buffer_head.h> |
| 17 | #include <linux/writeback.h> |
| 18 | #include <linux/pagevec.h> |
| 19 | #include <linux/mpage.h> |
| 20 | #include <linux/namei.h> |
| 21 | #include <linux/uio.h> |
| 22 | #include <linux/bio.h> |
| 23 | #include <linux/workqueue.h> |
| 24 | #include <linux/kernel.h> |
| 25 | #include <linux/slab.h> |
| 26 | |
| 27 | #include "ext4_jbd2.h" |
| 28 | #include "xattr.h" |
| 29 | #include "acl.h" |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 30 | |
| 31 | static struct kmem_cache *io_page_cachep, *io_end_cachep; |
| 32 | |
Theodore Ts'o | 5dabfc7 | 2010-10-27 21:30:14 -0400 | [diff] [blame] | 33 | int __init ext4_init_pageio(void) |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 34 | { |
| 35 | io_page_cachep = KMEM_CACHE(ext4_io_page, SLAB_RECLAIM_ACCOUNT); |
| 36 | if (io_page_cachep == NULL) |
| 37 | return -ENOMEM; |
| 38 | io_end_cachep = KMEM_CACHE(ext4_io_end, SLAB_RECLAIM_ACCOUNT); |
Dan Carpenter | 1319518 | 2011-01-10 12:10:44 -0500 | [diff] [blame] | 39 | if (io_end_cachep == NULL) { |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 40 | kmem_cache_destroy(io_page_cachep); |
| 41 | return -ENOMEM; |
| 42 | } |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 43 | return 0; |
| 44 | } |
| 45 | |
Theodore Ts'o | 5dabfc7 | 2010-10-27 21:30:14 -0400 | [diff] [blame] | 46 | void ext4_exit_pageio(void) |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 47 | { |
| 48 | kmem_cache_destroy(io_end_cachep); |
| 49 | kmem_cache_destroy(io_page_cachep); |
| 50 | } |
| 51 | |
Theodore Ts'o | f7ad6d2 | 2010-11-08 13:43:33 -0500 | [diff] [blame] | 52 | void ext4_ioend_wait(struct inode *inode) |
| 53 | { |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 54 | wait_queue_head_t *wq = ext4_ioend_wq(inode); |
Theodore Ts'o | f7ad6d2 | 2010-11-08 13:43:33 -0500 | [diff] [blame] | 55 | |
| 56 | wait_event(*wq, (atomic_read(&EXT4_I(inode)->i_ioend_count) == 0)); |
| 57 | } |
| 58 | |
Theodore Ts'o | 83668e7 | 2010-11-08 13:45:33 -0500 | [diff] [blame] | 59 | static void put_io_page(struct ext4_io_page *io_page) |
| 60 | { |
| 61 | if (atomic_dec_and_test(&io_page->p_count)) { |
Linus Torvalds | 6268b32 | 2012-03-29 17:00:56 -0700 | [diff] [blame] | 62 | end_page_writeback(io_page->p_page); |
Theodore Ts'o | 83668e7 | 2010-11-08 13:45:33 -0500 | [diff] [blame] | 63 | put_page(io_page->p_page); |
| 64 | kmem_cache_free(io_page_cachep, io_page); |
| 65 | } |
| 66 | } |
| 67 | |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 68 | void ext4_free_io_end(ext4_io_end_t *io) |
| 69 | { |
| 70 | int i; |
| 71 | |
| 72 | BUG_ON(!io); |
Dmitry Monakhov | 28a535f | 2012-09-29 00:14:55 -0400 | [diff] [blame] | 73 | BUG_ON(!list_empty(&io->list)); |
Dmitry Monakhov | 82e5422 | 2012-09-28 23:36:25 -0400 | [diff] [blame] | 74 | BUG_ON(io->flag & EXT4_IO_END_UNWRITTEN); |
| 75 | |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 76 | if (io->page) |
| 77 | put_page(io->page); |
Theodore Ts'o | 83668e7 | 2010-11-08 13:45:33 -0500 | [diff] [blame] | 78 | for (i = 0; i < io->num_io_pages; i++) |
| 79 | put_io_page(io->pages[i]); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 80 | io->num_io_pages = 0; |
Theodore Ts'o | 4e29802 | 2011-10-30 18:41:19 -0400 | [diff] [blame] | 81 | if (atomic_dec_and_test(&EXT4_I(io->inode)->i_ioend_count)) |
| 82 | wake_up_all(ext4_ioend_wq(io->inode)); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 83 | kmem_cache_free(io_end_cachep, io); |
| 84 | } |
| 85 | |
Dmitry Monakhov | 28a535f | 2012-09-29 00:14:55 -0400 | [diff] [blame] | 86 | /* check a range of space and convert unwritten extents to written. */ |
| 87 | static int ext4_end_io(ext4_io_end_t *io) |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 88 | { |
| 89 | struct inode *inode = io->inode; |
| 90 | loff_t offset = io->offset; |
| 91 | ssize_t size = io->size; |
| 92 | int ret = 0; |
| 93 | |
| 94 | ext4_debug("ext4_end_io_nolock: io 0x%p from inode %lu,list->next 0x%p," |
| 95 | "list->prev 0x%p\n", |
| 96 | io, inode->i_ino, io->list.next, io->list.prev); |
| 97 | |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 98 | ret = ext4_convert_unwritten_extents(inode, offset, size); |
| 99 | if (ret < 0) { |
Theodore Ts'o | b82e384 | 2011-10-31 10:56:32 -0400 | [diff] [blame] | 100 | ext4_msg(inode->i_sb, KERN_EMERG, |
| 101 | "failed to convert unwritten extents to written " |
| 102 | "extents -- potential data loss! " |
| 103 | "(inode %lu, offset %llu, size %zd, error %d)", |
| 104 | inode->i_ino, offset, size, ret); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 105 | } |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 106 | if (io->iocb) |
| 107 | aio_complete(io->iocb, io->result, 0); |
Eric Sandeen | e9e3bce | 2011-02-12 08:17:34 -0500 | [diff] [blame] | 108 | |
Jeff Moyer | 266991b | 2012-02-20 17:59:24 -0500 | [diff] [blame] | 109 | if (io->flag & EXT4_IO_END_DIRECT) |
| 110 | inode_dio_done(inode); |
Theodore Ts'o | b82e384 | 2011-10-31 10:56:32 -0400 | [diff] [blame] | 111 | /* Wake up anyone waiting on unwritten extent conversion */ |
Dmitry Monakhov | e27f41e | 2012-09-28 23:24:52 -0400 | [diff] [blame] | 112 | if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten)) |
Anatol Pomozov | 8d8c182 | 2012-11-08 14:53:35 -0500 | [diff] [blame] | 113 | wake_up_all(ext4_ioend_wq(inode)); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 114 | return ret; |
| 115 | } |
| 116 | |
Dmitry Monakhov | 28a535f | 2012-09-29 00:14:55 -0400 | [diff] [blame] | 117 | static void dump_completed_IO(struct inode *inode) |
| 118 | { |
| 119 | #ifdef EXT4FS_DEBUG |
| 120 | struct list_head *cur, *before, *after; |
| 121 | ext4_io_end_t *io, *io0, *io1; |
| 122 | unsigned long flags; |
| 123 | |
| 124 | if (list_empty(&EXT4_I(inode)->i_completed_io_list)) { |
| 125 | ext4_debug("inode %lu completed_io list is empty\n", |
| 126 | inode->i_ino); |
| 127 | return; |
| 128 | } |
| 129 | |
| 130 | ext4_debug("Dump inode %lu completed_io list\n", inode->i_ino); |
| 131 | list_for_each_entry(io, &EXT4_I(inode)->i_completed_io_list, list) { |
| 132 | cur = &io->list; |
| 133 | before = cur->prev; |
| 134 | io0 = container_of(before, ext4_io_end_t, list); |
| 135 | after = cur->next; |
| 136 | io1 = container_of(after, ext4_io_end_t, list); |
| 137 | |
| 138 | ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n", |
| 139 | io, inode->i_ino, io0, io1); |
| 140 | } |
| 141 | #endif |
| 142 | } |
| 143 | |
| 144 | /* Add the io_end to per-inode completed end_io list. */ |
| 145 | void ext4_add_complete_io(ext4_io_end_t *io_end) |
| 146 | { |
| 147 | struct ext4_inode_info *ei = EXT4_I(io_end->inode); |
| 148 | struct workqueue_struct *wq; |
| 149 | unsigned long flags; |
| 150 | |
| 151 | BUG_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN)); |
| 152 | wq = EXT4_SB(io_end->inode->i_sb)->dio_unwritten_wq; |
| 153 | |
| 154 | spin_lock_irqsave(&ei->i_completed_io_lock, flags); |
| 155 | if (list_empty(&ei->i_completed_io_list)) { |
| 156 | io_end->flag |= EXT4_IO_END_QUEUED; |
| 157 | queue_work(wq, &io_end->work); |
| 158 | } |
| 159 | list_add_tail(&io_end->list, &ei->i_completed_io_list); |
| 160 | spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); |
| 161 | } |
| 162 | |
| 163 | static int ext4_do_flush_completed_IO(struct inode *inode, |
| 164 | ext4_io_end_t *work_io) |
| 165 | { |
| 166 | ext4_io_end_t *io; |
| 167 | struct list_head unwritten, complete, to_free; |
| 168 | unsigned long flags; |
| 169 | struct ext4_inode_info *ei = EXT4_I(inode); |
| 170 | int err, ret = 0; |
| 171 | |
| 172 | INIT_LIST_HEAD(&complete); |
| 173 | INIT_LIST_HEAD(&to_free); |
| 174 | |
| 175 | spin_lock_irqsave(&ei->i_completed_io_lock, flags); |
| 176 | dump_completed_IO(inode); |
| 177 | list_replace_init(&ei->i_completed_io_list, &unwritten); |
| 178 | spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); |
| 179 | |
| 180 | while (!list_empty(&unwritten)) { |
| 181 | io = list_entry(unwritten.next, ext4_io_end_t, list); |
| 182 | BUG_ON(!(io->flag & EXT4_IO_END_UNWRITTEN)); |
| 183 | list_del_init(&io->list); |
| 184 | |
| 185 | err = ext4_end_io(io); |
| 186 | if (unlikely(!ret && err)) |
| 187 | ret = err; |
| 188 | |
| 189 | list_add_tail(&io->list, &complete); |
| 190 | } |
Dmitry Monakhov | 28a535f | 2012-09-29 00:14:55 -0400 | [diff] [blame] | 191 | spin_lock_irqsave(&ei->i_completed_io_lock, flags); |
| 192 | while (!list_empty(&complete)) { |
| 193 | io = list_entry(complete.next, ext4_io_end_t, list); |
| 194 | io->flag &= ~EXT4_IO_END_UNWRITTEN; |
| 195 | /* end_io context can not be destroyed now because it still |
| 196 | * used by queued worker. Worker thread will destroy it later */ |
| 197 | if (io->flag & EXT4_IO_END_QUEUED) |
| 198 | list_del_init(&io->list); |
| 199 | else |
| 200 | list_move(&io->list, &to_free); |
| 201 | } |
| 202 | /* If we are called from worker context, it is time to clear queued |
| 203 | * flag, and destroy it's end_io if it was converted already */ |
| 204 | if (work_io) { |
| 205 | work_io->flag &= ~EXT4_IO_END_QUEUED; |
| 206 | if (!(work_io->flag & EXT4_IO_END_UNWRITTEN)) |
| 207 | list_add_tail(&work_io->list, &to_free); |
| 208 | } |
| 209 | spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); |
| 210 | |
| 211 | while (!list_empty(&to_free)) { |
| 212 | io = list_entry(to_free.next, ext4_io_end_t, list); |
| 213 | list_del_init(&io->list); |
| 214 | ext4_free_io_end(io); |
| 215 | } |
| 216 | return ret; |
| 217 | } |
| 218 | |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 219 | /* |
| 220 | * work on completed aio dio IO, to convert unwritten extents to extents |
| 221 | */ |
| 222 | static void ext4_end_io_work(struct work_struct *work) |
| 223 | { |
Dmitry Monakhov | 28a535f | 2012-09-29 00:14:55 -0400 | [diff] [blame] | 224 | ext4_io_end_t *io = container_of(work, ext4_io_end_t, work); |
| 225 | ext4_do_flush_completed_IO(io->inode, io); |
| 226 | } |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 227 | |
Dmitry Monakhov | c278531 | 2012-10-05 11:31:55 -0400 | [diff] [blame] | 228 | int ext4_flush_unwritten_io(struct inode *inode) |
Dmitry Monakhov | 28a535f | 2012-09-29 00:14:55 -0400 | [diff] [blame] | 229 | { |
Dmitry Monakhov | c278531 | 2012-10-05 11:31:55 -0400 | [diff] [blame] | 230 | int ret; |
| 231 | WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex) && |
| 232 | !(inode->i_state & I_FREEING)); |
| 233 | ret = ext4_do_flush_completed_IO(inode, NULL); |
| 234 | ext4_unwritten_wait(inode); |
| 235 | return ret; |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 236 | } |
| 237 | |
| 238 | ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags) |
| 239 | { |
Jesper Juhl | b17b35e | 2010-12-19 21:41:55 -0500 | [diff] [blame] | 240 | ext4_io_end_t *io = kmem_cache_zalloc(io_end_cachep, flags); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 241 | if (io) { |
Theodore Ts'o | f7ad6d2 | 2010-11-08 13:43:33 -0500 | [diff] [blame] | 242 | atomic_inc(&EXT4_I(inode)->i_ioend_count); |
| 243 | io->inode = inode; |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 244 | INIT_WORK(&io->work, ext4_end_io_work); |
| 245 | INIT_LIST_HEAD(&io->list); |
| 246 | } |
| 247 | return io; |
| 248 | } |
| 249 | |
| 250 | /* |
| 251 | * Print an buffer I/O error compatible with the fs/buffer.c. This |
| 252 | * provides compatibility with dmesg scrapers that look for a specific |
| 253 | * buffer I/O error message. We really need a unified error reporting |
| 254 | * structure to userspace ala Digital Unix's uerf system, but it's |
| 255 | * probably not going to happen in my lifetime, due to LKML politics... |
| 256 | */ |
| 257 | static void buffer_io_error(struct buffer_head *bh) |
| 258 | { |
| 259 | char b[BDEVNAME_SIZE]; |
| 260 | printk(KERN_ERR "Buffer I/O error on device %s, logical block %llu\n", |
| 261 | bdevname(bh->b_bdev, b), |
| 262 | (unsigned long long)bh->b_blocknr); |
| 263 | } |
| 264 | |
| 265 | static void ext4_end_bio(struct bio *bio, int error) |
| 266 | { |
| 267 | ext4_io_end_t *io_end = bio->bi_private; |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 268 | struct inode *inode; |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 269 | int i; |
Curt Wohlgemuth | d50bdd5 | 2011-02-07 12:46:14 -0500 | [diff] [blame] | 270 | sector_t bi_sector = bio->bi_sector; |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 271 | |
| 272 | BUG_ON(!io_end); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 273 | bio->bi_private = NULL; |
| 274 | bio->bi_end_io = NULL; |
| 275 | if (test_bit(BIO_UPTODATE, &bio->bi_flags)) |
| 276 | error = 0; |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 277 | bio_put(bio); |
| 278 | |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 279 | for (i = 0; i < io_end->num_io_pages; i++) { |
| 280 | struct page *page = io_end->pages[i]->p_page; |
| 281 | struct buffer_head *bh, *head; |
Curt Wohlgemuth | 39db00f | 2011-04-30 13:26:26 -0400 | [diff] [blame] | 282 | loff_t offset; |
| 283 | loff_t io_end_offset; |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 284 | |
Curt Wohlgemuth | 39db00f | 2011-04-30 13:26:26 -0400 | [diff] [blame] | 285 | if (error) { |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 286 | SetPageError(page); |
Curt Wohlgemuth | 39db00f | 2011-04-30 13:26:26 -0400 | [diff] [blame] | 287 | set_bit(AS_EIO, &page->mapping->flags); |
| 288 | head = page_buffers(page); |
| 289 | BUG_ON(!head); |
| 290 | |
| 291 | io_end_offset = io_end->offset + io_end->size; |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 292 | |
| 293 | offset = (sector_t) page->index << PAGE_CACHE_SHIFT; |
| 294 | bh = head; |
| 295 | do { |
| 296 | if ((offset >= io_end->offset) && |
Curt Wohlgemuth | 39db00f | 2011-04-30 13:26:26 -0400 | [diff] [blame] | 297 | (offset+bh->b_size <= io_end_offset)) |
| 298 | buffer_io_error(bh); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 299 | |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 300 | offset += bh->b_size; |
| 301 | bh = bh->b_this_page; |
| 302 | } while (bh != head); |
| 303 | } |
| 304 | |
Linus Torvalds | 6268b32 | 2012-03-29 17:00:56 -0700 | [diff] [blame] | 305 | put_io_page(io_end->pages[i]); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 306 | } |
Linus Torvalds | 6268b32 | 2012-03-29 17:00:56 -0700 | [diff] [blame] | 307 | io_end->num_io_pages = 0; |
Theodore Ts'o | f7ad6d2 | 2010-11-08 13:43:33 -0500 | [diff] [blame] | 308 | inode = io_end->inode; |
| 309 | |
| 310 | if (error) { |
| 311 | io_end->flag |= EXT4_IO_END_ERROR; |
| 312 | ext4_warning(inode->i_sb, "I/O error writing to inode %lu " |
| 313 | "(offset %llu size %ld starting block %llu)", |
| 314 | inode->i_ino, |
| 315 | (unsigned long long) io_end->offset, |
| 316 | (long) io_end->size, |
| 317 | (unsigned long long) |
Curt Wohlgemuth | d50bdd5 | 2011-02-07 12:46:14 -0500 | [diff] [blame] | 318 | bi_sector >> (inode->i_blkbits - 9)); |
Theodore Ts'o | f7ad6d2 | 2010-11-08 13:43:33 -0500 | [diff] [blame] | 319 | } |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 320 | |
Theodore Ts'o | b616844 | 2011-02-28 13:12:38 -0500 | [diff] [blame] | 321 | if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) { |
| 322 | ext4_free_io_end(io_end); |
| 323 | return; |
| 324 | } |
| 325 | |
Dmitry Monakhov | 28a535f | 2012-09-29 00:14:55 -0400 | [diff] [blame] | 326 | ext4_add_complete_io(io_end); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 327 | } |
| 328 | |
| 329 | void ext4_io_submit(struct ext4_io_submit *io) |
| 330 | { |
| 331 | struct bio *bio = io->io_bio; |
| 332 | |
| 333 | if (bio) { |
| 334 | bio_get(io->io_bio); |
| 335 | submit_bio(io->io_op, io->io_bio); |
| 336 | BUG_ON(bio_flagged(io->io_bio, BIO_EOPNOTSUPP)); |
| 337 | bio_put(io->io_bio); |
| 338 | } |
Peter Huewe | 7dc5761 | 2011-02-21 21:01:42 -0500 | [diff] [blame] | 339 | io->io_bio = NULL; |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 340 | io->io_op = 0; |
Peter Huewe | 7dc5761 | 2011-02-21 21:01:42 -0500 | [diff] [blame] | 341 | io->io_end = NULL; |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 342 | } |
| 343 | |
| 344 | static int io_submit_init(struct ext4_io_submit *io, |
| 345 | struct inode *inode, |
| 346 | struct writeback_control *wbc, |
| 347 | struct buffer_head *bh) |
| 348 | { |
| 349 | ext4_io_end_t *io_end; |
| 350 | struct page *page = bh->b_page; |
| 351 | int nvecs = bio_get_nr_vecs(bh->b_bdev); |
| 352 | struct bio *bio; |
| 353 | |
| 354 | io_end = ext4_init_io_end(inode, GFP_NOFS); |
| 355 | if (!io_end) |
| 356 | return -ENOMEM; |
Theodore Ts'o | 275d3ba | 2011-06-29 21:44:45 -0400 | [diff] [blame] | 357 | bio = bio_alloc(GFP_NOIO, min(nvecs, BIO_MAX_PAGES)); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 358 | bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9); |
| 359 | bio->bi_bdev = bh->b_bdev; |
| 360 | bio->bi_private = io->io_end = io_end; |
| 361 | bio->bi_end_io = ext4_end_bio; |
| 362 | |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 363 | io_end->offset = (page->index << PAGE_CACHE_SHIFT) + bh_offset(bh); |
| 364 | |
| 365 | io->io_bio = bio; |
Jens Axboe | 721a960 | 2011-03-09 11:56:30 +0100 | [diff] [blame] | 366 | io->io_op = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 367 | io->io_next_block = bh->b_blocknr; |
| 368 | return 0; |
| 369 | } |
| 370 | |
| 371 | static int io_submit_add_bh(struct ext4_io_submit *io, |
| 372 | struct ext4_io_page *io_page, |
| 373 | struct inode *inode, |
| 374 | struct writeback_control *wbc, |
| 375 | struct buffer_head *bh) |
| 376 | { |
| 377 | ext4_io_end_t *io_end; |
| 378 | int ret; |
| 379 | |
| 380 | if (buffer_new(bh)) { |
| 381 | clear_buffer_new(bh); |
| 382 | unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr); |
| 383 | } |
| 384 | |
| 385 | if (!buffer_mapped(bh) || buffer_delay(bh)) { |
| 386 | if (!buffer_mapped(bh)) |
| 387 | clear_buffer_dirty(bh); |
| 388 | if (io->io_bio) |
| 389 | ext4_io_submit(io); |
| 390 | return 0; |
| 391 | } |
| 392 | |
| 393 | if (io->io_bio && bh->b_blocknr != io->io_next_block) { |
| 394 | submit_and_retry: |
| 395 | ext4_io_submit(io); |
| 396 | } |
| 397 | if (io->io_bio == NULL) { |
| 398 | ret = io_submit_init(io, inode, wbc, bh); |
| 399 | if (ret) |
| 400 | return ret; |
| 401 | } |
| 402 | io_end = io->io_end; |
| 403 | if ((io_end->num_io_pages >= MAX_IO_PAGES) && |
| 404 | (io_end->pages[io_end->num_io_pages-1] != io_page)) |
| 405 | goto submit_and_retry; |
Tao Ma | 0edeb71 | 2011-10-31 17:30:44 -0400 | [diff] [blame] | 406 | if (buffer_uninit(bh)) |
| 407 | ext4_set_io_unwritten_flag(inode, io_end); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 408 | io->io_end->size += bh->b_size; |
| 409 | io->io_next_block++; |
| 410 | ret = bio_add_page(io->io_bio, bh->b_page, bh->b_size, bh_offset(bh)); |
| 411 | if (ret != bh->b_size) |
| 412 | goto submit_and_retry; |
| 413 | if ((io_end->num_io_pages == 0) || |
| 414 | (io_end->pages[io_end->num_io_pages-1] != io_page)) { |
| 415 | io_end->pages[io_end->num_io_pages++] = io_page; |
Theodore Ts'o | 83668e7 | 2010-11-08 13:45:33 -0500 | [diff] [blame] | 416 | atomic_inc(&io_page->p_count); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 417 | } |
| 418 | return 0; |
| 419 | } |
| 420 | |
| 421 | int ext4_bio_write_page(struct ext4_io_submit *io, |
| 422 | struct page *page, |
| 423 | int len, |
| 424 | struct writeback_control *wbc) |
| 425 | { |
| 426 | struct inode *inode = page->mapping->host; |
| 427 | unsigned block_start, block_end, blocksize; |
| 428 | struct ext4_io_page *io_page; |
| 429 | struct buffer_head *bh, *head; |
| 430 | int ret = 0; |
| 431 | |
| 432 | blocksize = 1 << inode->i_blkbits; |
| 433 | |
Curt Wohlgemuth | d50bdd5 | 2011-02-07 12:46:14 -0500 | [diff] [blame] | 434 | BUG_ON(!PageLocked(page)); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 435 | BUG_ON(PageWriteback(page)); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 436 | |
| 437 | io_page = kmem_cache_alloc(io_page_cachep, GFP_NOFS); |
| 438 | if (!io_page) { |
| 439 | set_page_dirty(page); |
| 440 | unlock_page(page); |
| 441 | return -ENOMEM; |
| 442 | } |
| 443 | io_page->p_page = page; |
Theodore Ts'o | 83668e7 | 2010-11-08 13:45:33 -0500 | [diff] [blame] | 444 | atomic_set(&io_page->p_count, 1); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 445 | get_page(page); |
Theodore Ts'o | a54aa76 | 2011-02-27 16:43:24 -0500 | [diff] [blame] | 446 | set_page_writeback(page); |
| 447 | ClearPageError(page); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 448 | |
| 449 | for (bh = head = page_buffers(page), block_start = 0; |
| 450 | bh != head || !block_start; |
| 451 | block_start = block_end, bh = bh->b_this_page) { |
Curt Wohlgemuth | d50bdd5 | 2011-02-07 12:46:14 -0500 | [diff] [blame] | 452 | |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 453 | block_end = block_start + blocksize; |
| 454 | if (block_start >= len) { |
Yongqiang Yang | 5a0dc73 | 2011-12-13 22:29:12 -0500 | [diff] [blame] | 455 | /* |
| 456 | * Comments copied from block_write_full_page_endio: |
| 457 | * |
| 458 | * The page straddles i_size. It must be zeroed out on |
| 459 | * each and every writepage invocation because it may |
| 460 | * be mmapped. "A file is mapped in multiples of the |
| 461 | * page size. For a file that is not a multiple of |
| 462 | * the page size, the remaining memory is zeroed when |
| 463 | * mapped, and writes to that region are not written |
| 464 | * out to the file." |
| 465 | */ |
| 466 | zero_user_segment(page, block_start, block_end); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 467 | clear_buffer_dirty(bh); |
| 468 | set_buffer_uptodate(bh); |
| 469 | continue; |
| 470 | } |
Curt Wohlgemuth | d50bdd5 | 2011-02-07 12:46:14 -0500 | [diff] [blame] | 471 | clear_buffer_dirty(bh); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 472 | ret = io_submit_add_bh(io, io_page, inode, wbc, bh); |
| 473 | if (ret) { |
| 474 | /* |
| 475 | * We only get here on ENOMEM. Not much else |
| 476 | * we can do but mark the page as dirty, and |
| 477 | * better luck next time. |
| 478 | */ |
| 479 | set_page_dirty(page); |
| 480 | break; |
| 481 | } |
| 482 | } |
| 483 | unlock_page(page); |
| 484 | /* |
| 485 | * If the page was truncated before we could do the writeback, |
| 486 | * or we had a memory allocation error while trying to write |
| 487 | * the first buffer head, we won't have submitted any pages for |
| 488 | * I/O. In that case we need to make sure we've cleared the |
| 489 | * PageWriteback bit from the page to prevent the system from |
| 490 | * wedging later on. |
| 491 | */ |
Theodore Ts'o | 83668e7 | 2010-11-08 13:45:33 -0500 | [diff] [blame] | 492 | put_io_page(io_page); |
Theodore Ts'o | bd2d021 | 2010-10-27 21:30:10 -0400 | [diff] [blame] | 493 | return ret; |
| 494 | } |