diff options
Diffstat (limited to 'fs/exfat/file.c')
| -rw-r--r-- | fs/exfat/file.c | 200 |
1 files changed, 179 insertions, 21 deletions
diff --git a/fs/exfat/file.c b/fs/exfat/file.c index bfdfafe00993..cc00f1a7a1e1 100644 --- a/fs/exfat/file.c +++ b/fs/exfat/file.c @@ -11,37 +11,83 @@ #include <linux/fsnotify.h> #include <linux/security.h> #include <linux/msdos_fs.h> +#include <linux/writeback.h> #include "exfat_raw.h" #include "exfat_fs.h" static int exfat_cont_expand(struct inode *inode, loff_t size) { - struct address_space *mapping = inode->i_mapping; - loff_t start = i_size_read(inode), count = size - i_size_read(inode); - int err, err2; + int ret; + unsigned int num_clusters, new_num_clusters, last_clu; + struct exfat_inode_info *ei = EXFAT_I(inode); + struct super_block *sb = inode->i_sb; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct exfat_chain clu; - err = generic_cont_expand_simple(inode, size); - if (err) - return err; + ret = inode_newsize_ok(inode, size); + if (ret) + return ret; + + num_clusters = EXFAT_B_TO_CLU_ROUND_UP(ei->i_size_ondisk, sbi); + new_num_clusters = EXFAT_B_TO_CLU_ROUND_UP(size, sbi); + + if (new_num_clusters == num_clusters) + goto out; + + if (num_clusters) { + exfat_chain_set(&clu, ei->start_clu, num_clusters, ei->flags); + ret = exfat_find_last_cluster(sb, &clu, &last_clu); + if (ret) + return ret; + + clu.dir = last_clu + 1; + } else { + last_clu = EXFAT_EOF_CLUSTER; + clu.dir = EXFAT_EOF_CLUSTER; + } + + clu.size = 0; + clu.flags = ei->flags; + + ret = exfat_alloc_cluster(inode, new_num_clusters - num_clusters, + &clu, IS_DIRSYNC(inode)); + if (ret) + return ret; + + /* Append new clusters to chain */ + if (num_clusters) { + if (clu.flags != ei->flags) + if (exfat_chain_cont_cluster(sb, ei->start_clu, num_clusters)) + goto free_clu; + + if (clu.flags == ALLOC_FAT_CHAIN) + if (exfat_ent_set(sb, last_clu, clu.dir)) + goto free_clu; + } else + ei->start_clu = clu.dir; + + ei->flags = clu.flags; +out: inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); - mark_inode_dirty(inode); + /* Expanded range not zeroed, do not update valid_size */ + i_size_write(inode, size); - if (!IS_SYNC(inode)) - return 0; + ei->i_size_aligned = round_up(size, sb->s_blocksize); + ei->i_size_ondisk = ei->i_size_aligned; + inode->i_blocks = round_up(size, sbi->cluster_size) >> 9; - err = filemap_fdatawrite_range(mapping, start, start + count - 1); - err2 = sync_mapping_buffers(mapping); - if (!err) - err = err2; - err2 = write_inode_now(inode, 1); - if (!err) - err = err2; - if (err) - return err; + if (IS_DIRSYNC(inode)) + return write_inode_now(inode, 1); + + mark_inode_dirty(inode); + + return 0; - return filemap_fdatawait_range(mapping, start, start + count - 1); +free_clu: + exfat_free_cluster(inode, &clu); + return -EIO; } static bool exfat_allow_set_time(struct exfat_sb_info *sbi, struct inode *inode) @@ -146,6 +192,9 @@ int __exfat_truncate(struct inode *inode) ei->start_clu = EXFAT_EOF_CLUSTER; } + if (i_size_read(inode) < ei->valid_size) + ei->valid_size = i_size_read(inode); + if (ei->type == TYPE_FILE) ei->attr |= EXFAT_ATTR_ARCHIVE; @@ -474,15 +523,124 @@ int exfat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync) return blkdev_issue_flush(inode->i_sb->s_bdev); } +static int exfat_file_zeroed_range(struct file *file, loff_t start, loff_t end) +{ + int err; + struct inode *inode = file_inode(file); + struct address_space *mapping = inode->i_mapping; + const struct address_space_operations *ops = mapping->a_ops; + + while (start < end) { + u32 zerofrom, len; + struct page *page = NULL; + + zerofrom = start & (PAGE_SIZE - 1); + len = PAGE_SIZE - zerofrom; + if (start + len > end) + len = end - start; + + err = ops->write_begin(file, mapping, start, len, &page, NULL); + if (err) + goto out; + + zero_user_segment(page, zerofrom, zerofrom + len); + + err = ops->write_end(file, mapping, start, len, len, page, NULL); + if (err < 0) + goto out; + start += len; + + balance_dirty_pages_ratelimited(mapping); + cond_resched(); + } + +out: + return err; +} + +static ssize_t exfat_file_write_iter(struct kiocb *iocb, struct iov_iter *iter) +{ + ssize_t ret; + struct file *file = iocb->ki_filp; + struct inode *inode = file_inode(file); + struct exfat_inode_info *ei = EXFAT_I(inode); + loff_t pos = iocb->ki_pos; + loff_t valid_size; + + inode_lock(inode); + + valid_size = ei->valid_size; + + ret = generic_write_checks(iocb, iter); + if (ret < 0) + goto unlock; + + if (pos > valid_size) { + ret = exfat_file_zeroed_range(file, valid_size, pos); + if (ret < 0 && ret != -ENOSPC) { + exfat_err(inode->i_sb, + "write: fail to zero from %llu to %llu(%zd)", + valid_size, pos, ret); + } + if (ret < 0) + goto unlock; + } + + ret = __generic_file_write_iter(iocb, iter); + if (ret < 0) + goto unlock; + + inode_unlock(inode); + + if (pos > valid_size) + pos = valid_size; + + if (iocb_is_dsync(iocb) && iocb->ki_pos > pos) { + ssize_t err = vfs_fsync_range(file, pos, iocb->ki_pos - 1, + iocb->ki_flags & IOCB_SYNC); + if (err < 0) + return err; + } + + return ret; + +unlock: + inode_unlock(inode); + + return ret; +} + +static int exfat_file_mmap(struct file *file, struct vm_area_struct *vma) +{ + int ret; + struct inode *inode = file_inode(file); + struct exfat_inode_info *ei = EXFAT_I(inode); + loff_t start = ((loff_t)vma->vm_pgoff << PAGE_SHIFT); + loff_t end = min_t(loff_t, i_size_read(inode), + start + vma->vm_end - vma->vm_start); + + if ((vma->vm_flags & VM_WRITE) && ei->valid_size < end) { + ret = exfat_file_zeroed_range(file, ei->valid_size, end); + if (ret < 0) { + exfat_err(inode->i_sb, + "mmap: fail to zero from %llu to %llu(%d)", + start, end, ret); + return ret; + } + } + + return generic_file_mmap(file, vma); +} + const struct file_operations exfat_file_operations = { .llseek = generic_file_llseek, .read_iter = generic_file_read_iter, - .write_iter = generic_file_write_iter, + .write_iter = exfat_file_write_iter, .unlocked_ioctl = exfat_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = exfat_compat_ioctl, #endif - .mmap = generic_file_mmap, + .mmap = exfat_file_mmap, .fsync = exfat_file_fsync, .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, |