On Tue, May 29, 2018 at 6:41 PM, Amir Goldstein <amir73il@xxxxxxxxx> wrote:
> On Tue, May 29, 2018 at 5:43 PM, Miklos Szeredi <mszeredi@xxxxxxxxxx> wrote:
>> Extract vfs_dedupe_file_range_one() helper to deal with a single dedup
>> request.
>>
>> Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
>> ---
>> fs/read_write.c | 89 +++++++++++++++++++++++++++++++--------------------------
>> 1 file changed, 49 insertions(+), 40 deletions(-)
>>
>> diff --git a/fs/read_write.c b/fs/read_write.c
>> index 1818581cadf6..82a53c44c0aa 100644
>> --- a/fs/read_write.c
>> +++ b/fs/read_write.c
>> @@ -1964,6 +1964,44 @@ int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
>> }
>> EXPORT_SYMBOL(vfs_dedupe_file_range_compare);
>>
>> +static s64 vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
>> + struct file *dst_file, loff_t dst_pos,
>> + u64 len)
>> +{
>> + s64 ret;
>> +
>> + ret = mnt_want_write_file(dst_file);
>> + if (ret)
>> + return ret;
>> +
>> + ret = clone_verify_area(dst_file, dst_pos, len, true);
>> + if (ret < 0)
>> + goto out_drop_write;
>> +
>> + ret = -EINVAL;
>> + if (!(capable(CAP_SYS_ADMIN) || (dst_file->f_mode & FMODE_WRITE)))
>> + goto out_drop_write;
>> +
>> + ret = -EXDEV;
>> + if (src_file->f_path.mnt != dst_file->f_path.mnt)
>> + goto out_drop_write;
>> +
>> + ret = -EISDIR;
>> + if (S_ISDIR(file_inode(dst_file)->i_mode))
>> + goto out_drop_write;
>> +
>> + ret = -EINVAL;
>> + if (!dst_file->f_op->dedupe_file_range)
>> + goto out_drop_write;
>> +
>> + ret = dst_file->f_op->dedupe_file_range(src_file, src_pos,
>> + dst_file, dst_pos, len);
>> +out_drop_write:
>> + mnt_drop_write_file(dst_file);
>> +
>> + return ret;
>> +}
>> +
>> int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
>> {
>> struct file_dedupe_range_info *info;
>> @@ -1972,10 +2010,7 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
>> u64 len;
>> int i;
>> int ret;
>> - bool is_admin = capable(CAP_SYS_ADMIN);
>> u16 count = same->dest_count;
>> - struct file *dst_file;
>> - loff_t dst_off;
>> loff_t deduped;
>>
>> if (!(file->f_mode & FMODE_READ))
>> @@ -2010,54 +2045,28 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
>> }
>>
>> for (i = 0, info = same->info; i < count; i++, info++) {
>> - struct inode *dst;
>> struct fd dst_fd = fdget(info->dest_fd);
>> + struct file *dst_file = dst_fd.file;
>>
>> - dst_file = dst_fd.file;
>> if (!dst_file) {
>> info->status = -EBADF;
>> goto next_loop;
>> }
>> - dst = file_inode(dst_file);
>> -
>> - ret = mnt_want_write_file(dst_file);
>> - if (ret) {
>> - info->status = ret;
>> - goto next_loop;
>> - }
>> -
>> - dst_off = info->dest_offset;
>> - ret = clone_verify_area(dst_file, dst_off, len, true);
>> - if (ret < 0) {
>> - info->status = ret;
>> - goto next_file;
>> - }
>> - ret = 0;
>>
>> if (info->reserved) {
>> info->status = -EINVAL;
>> - } else if (!(is_admin || (dst_file->f_mode & FMODE_WRITE))) {
>> - info->status = -EINVAL;
>> - } else if (file->f_path.mnt != dst_file->f_path.mnt) {
>> - info->status = -EXDEV;
>> - } else if (S_ISDIR(dst->i_mode)) {
>> - info->status = -EISDIR;
>> - } else if (dst_file->f_op->dedupe_file_range == NULL) {
>> - info->status = -EINVAL;
>> - } else {
>> - deduped = dst_file->f_op->dedupe_file_range(file, off,
>> - dst_file,
>> - info->dest_offset, len);
>> - if (deduped == -EBADE)
>> - info->status = FILE_DEDUPE_RANGE_DIFFERS;
>> - else if (deduped < 0)
>> - info->status = deduped;
>> - else
>> - info->bytes_deduped += deduped;
>> + goto next_loop;
>> }
>>
>> -next_file:
>> - mnt_drop_write_file(dst_file);
>> + deduped = vfs_dedupe_file_range_one(file, off, dst_file,
>> + info->dest_offset, len);
>> + if (deduped == -EBADE)
>> + info->status = FILE_DEDUPE_RANGE_DIFFERS;
>> + else if (deduped < 0)
>> + info->status = deduped;
>> + else
>> + info->bytes_deduped += deduped;
>> +
>> next_loop:
>> fdput(dst_fd);
>>
>
> Please note that this patch conflicts with but is also an alternative to commit
> 227627114799 fs: avoid fdput() after failed fdget() in vfs_dedupe_file_range()
> on Al's fixes => for-next branch.
>
Sorry, that's a conflict, and a rather trivial one, but Miklos' patch is not
an alternative fix.
Thanks,
Amir.
