diff options
| -rw-r--r-- | fs/read_write.c | 37 | ||||
| -rw-r--r-- | include/linux/fs.h | 2 |
2 files changed, 30 insertions, 9 deletions
diff --git a/fs/read_write.c b/fs/read_write.c index 672b187def62..dfd125798791 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -51,23 +51,23 @@ static loff_t lseek_execute(struct file *file, struct inode *inode, } /** - * generic_file_llseek - generic llseek implementation for regular files + * generic_file_llseek_size - generic llseek implementation for regular files * @file: file structure to seek on * @offset: file offset to seek to * @origin: type of seek + * @size: max size of file system * - * This is a generic implemenation of ->llseek usable for all normal local - * filesystems. It just updates the file offset to the value specified by - * @offset and @origin under i_mutex. + * This is a variant of generic_file_llseek that allows passing in a custom + * file size. * * Synchronization: - * SEEK_SET is unsynchronized (but atomic on 64bit platforms) + * SEEK_SET and SEEK_END are unsynchronized (but atomic on 64bit platforms) * SEEK_CUR is synchronized against other SEEK_CURs, but not read/writes. * read/writes behave like SEEK_SET against seeks. - * SEEK_END */ loff_t -generic_file_llseek(struct file *file, loff_t offset, int origin) +generic_file_llseek_size(struct file *file, loff_t offset, int origin, + loff_t maxsize) { struct inode *inode = file->f_mapping->host; @@ -91,7 +91,7 @@ generic_file_llseek(struct file *file, loff_t offset, int origin) */ spin_lock(&file->f_lock); offset = lseek_execute(file, inode, file->f_pos + offset, - inode->i_sb->s_maxbytes); + maxsize); spin_unlock(&file->f_lock); return offset; case SEEK_DATA: @@ -113,7 +113,26 @@ generic_file_llseek(struct file *file, loff_t offset, int origin) break; } - return lseek_execute(file, inode, offset, inode->i_sb->s_maxbytes); + return lseek_execute(file, inode, offset, maxsize); +} +EXPORT_SYMBOL(generic_file_llseek_size); + +/** + * generic_file_llseek - generic llseek implementation for regular files + * @file: file structure to seek on + * @offset: file offset to seek to + * @origin: type of seek + * + * This is a generic implemenation of ->llseek useable for all normal local + * filesystems. It just updates the file offset to the value specified by + * @offset and @origin under i_mutex. + */ +loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) +{ + struct inode *inode = file->f_mapping->host; + + return generic_file_llseek_size(file, offset, origin, + inode->i_sb->s_maxbytes); } EXPORT_SYMBOL(generic_file_llseek); diff --git a/include/linux/fs.h b/include/linux/fs.h index db85196f6308..d055cc7d7240 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2403,6 +2403,8 @@ file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping); extern loff_t noop_llseek(struct file *file, loff_t offset, int origin); extern loff_t no_llseek(struct file *file, loff_t offset, int origin); extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin); +extern loff_t generic_file_llseek_size(struct file *file, loff_t offset, + int origin, loff_t maxsize); extern int generic_file_open(struct inode * inode, struct file * filp); extern int nonseekable_open(struct inode * inode, struct file * filp); |