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authorChao Yu <chao2.yu@samsung.com>2014-04-23 02:10:24 -0400
committerJaegeuk Kim <jaegeuk.kim@samsung.com>2014-05-06 21:21:57 -0400
commit267378d4de696d4397cd611e62957d19b2a61357 (patch)
treefdcc2b128e16060b5b451f9b8405a424534f7b17
parent2163d19815b3dfdb243cee2de2478ae7efce1942 (diff)
f2fs: introduce f2fs_seek_block to support SEEK_{DATA, HOLE} in llseek
In This patch we introduce f2fs_seek_block to support SEEK_{DATA,HOLE} of lseek(2). change log from v1: o fix bug when lseek from middle of page and fix wrong calculation of PGOFS_OF_NEXT_DNODE macro. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
-rw-r--r--fs/f2fs/f2fs.h6
-rw-r--r--fs/f2fs/file.c92
2 files changed, 97 insertions, 1 deletions
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 1ca958ab40e3..e77be7cb1e60 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1079,6 +1079,12 @@ static inline void f2fs_stop_checkpoint(struct f2fs_sb_info *sbi)
1079 ((is_inode_flag_set(F2FS_I(i), FI_ACL_MODE)) ? \ 1079 ((is_inode_flag_set(F2FS_I(i), FI_ACL_MODE)) ? \
1080 (F2FS_I(i)->i_acl_mode) : ((i)->i_mode)) 1080 (F2FS_I(i)->i_acl_mode) : ((i)->i_mode))
1081 1081
1082/* get offset of first page in next direct node */
1083#define PGOFS_OF_NEXT_DNODE(pgofs, fi) \
1084 ((pgofs < ADDRS_PER_INODE(fi)) ? ADDRS_PER_INODE(fi) : \
1085 (pgofs - ADDRS_PER_INODE(fi) + ADDRS_PER_BLOCK) / \
1086 ADDRS_PER_BLOCK * ADDRS_PER_BLOCK + ADDRS_PER_INODE(fi))
1087
1082/* 1088/*
1083 * file.c 1089 * file.c
1084 */ 1090 */
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index bb365c932555..d99d17325046 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -194,6 +194,96 @@ out:
194 return ret; 194 return ret;
195} 195}
196 196
197static loff_t f2fs_seek_block(struct file *file, loff_t offset, int whence)
198{
199 struct inode *inode = file->f_mapping->host;
200 loff_t maxbytes = inode->i_sb->s_maxbytes;
201 struct dnode_of_data dn;
202 pgoff_t pgofs, end_offset;
203 loff_t data_ofs = offset, isize;
204 int err = 0;
205
206 mutex_lock(&inode->i_mutex);
207
208 isize = i_size_read(inode);
209 if (offset >= isize)
210 goto fail;
211
212 /* handle inline data case */
213 if (f2fs_has_inline_data(inode)) {
214 if (whence == SEEK_HOLE)
215 data_ofs = isize;
216 goto found;
217 }
218
219 pgofs = (pgoff_t)(offset >> PAGE_CACHE_SHIFT);
220
221 for (; data_ofs < isize; data_ofs = pgofs << PAGE_CACHE_SHIFT) {
222 set_new_dnode(&dn, inode, NULL, NULL, 0);
223 err = get_dnode_of_data(&dn, pgofs, LOOKUP_NODE_RA);
224 if (err && err != -ENOENT) {
225 goto fail;
226 } else if (err == -ENOENT) {
227 /* direct node is not exist */
228 if (whence == SEEK_DATA) {
229 pgofs = PGOFS_OF_NEXT_DNODE(pgofs,
230 F2FS_I(inode));
231 continue;
232 } else {
233 goto found;
234 }
235 }
236
237 end_offset = IS_INODE(dn.node_page) ?
238 ADDRS_PER_INODE(F2FS_I(inode)) : ADDRS_PER_BLOCK;
239
240 /* find data/hole in dnode block */
241 for (; dn.ofs_in_node < end_offset;
242 dn.ofs_in_node++, pgofs++,
243 data_ofs = pgofs << PAGE_CACHE_SHIFT) {
244 block_t blkaddr;
245 blkaddr = datablock_addr(dn.node_page, dn.ofs_in_node);
246
247 if ((whence == SEEK_DATA && blkaddr != NULL_ADDR) ||
248 (whence == SEEK_HOLE && blkaddr == NULL_ADDR)) {
249 f2fs_put_dnode(&dn);
250 goto found;
251 }
252 }
253 f2fs_put_dnode(&dn);
254 }
255
256 if (whence == SEEK_DATA)
257 goto fail;
258 else
259 data_ofs = isize;
260found:
261 mutex_unlock(&inode->i_mutex);
262 return vfs_setpos(file, data_ofs, maxbytes);
263fail:
264 mutex_unlock(&inode->i_mutex);
265 return -ENXIO;
266}
267
268static loff_t f2fs_llseek(struct file *file, loff_t offset, int whence)
269{
270 struct inode *inode = file->f_mapping->host;
271 loff_t maxbytes = inode->i_sb->s_maxbytes;
272
273 switch (whence) {
274 case SEEK_SET:
275 case SEEK_CUR:
276 case SEEK_END:
277 return generic_file_llseek_size(file, offset, whence,
278 maxbytes, i_size_read(inode));
279 case SEEK_DATA:
280 case SEEK_HOLE:
281 return f2fs_seek_block(file, offset, whence);
282 }
283
284 return -EINVAL;
285}
286
197static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma) 287static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma)
198{ 288{
199 file_accessed(file); 289 file_accessed(file);
@@ -675,7 +765,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
675#endif 765#endif
676 766
677const struct file_operations f2fs_file_operations = { 767const struct file_operations f2fs_file_operations = {
678 .llseek = generic_file_llseek, 768 .llseek = f2fs_llseek,
679 .read = do_sync_read, 769 .read = do_sync_read,
680 .write = do_sync_write, 770 .write = do_sync_write,
681 .aio_read = generic_file_aio_read, 771 .aio_read = generic_file_aio_read,