[v2] xfsprogs: io/copy_range: cover corner case (fd_in == fd_out)
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Message ID 20190903111903.12231-1-yin-jianhong@163.com
State New
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Series
  • [v2] xfsprogs: io/copy_range: cover corner case (fd_in == fd_out)
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Commit Message

Jianhong.Yin Sept. 3, 2019, 11:19 a.m. UTC
Related bug:
  copy_file_range return "Invalid argument" when copy in the same file
  https://bugzilla.kernel.org/show_bug.cgi?id=202935

if argument of option -f is "-", use current file->fd as fd_in

Usage:
  xfs_io -c 'copy_range -f -' some_file

Signed-off-by: Jianhong Yin <yin-jianhong@163.com>
---
 io/copy_file_range.c | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

Comments

Eric Sandeen Sept. 3, 2019, 5:54 p.m. UTC | #1
On 9/3/19 6:19 AM, Jianhong.Yin wrote:
> Related bug:
>   copy_file_range return "Invalid argument" when copy in the same file
>   https://bugzilla.kernel.org/show_bug.cgi?id=202935

that's a CIFS bug though, not related to how xfs_io operates, correct?

What is the failing xfs_io case?  Because this seems to work fine here:

# fallocate -l 128m testfile
# strace -eopen,copy_file_range xfs_io -c "copy_range -s 1m -d 8m -l 2m testfile" testfile
...
open("testfile", O_RDWR)                = 3
...
open("testfile", O_RDONLY)              = 4
copy_file_range(4, [1048576], 3, [8388608], 2097152, 0) = 2097152
+++ exited with 0 +++

this works too:

# strace -eopen,copy_file_range xfs_io -c "copy_range testfile" testfile
...
open("testfile", O_RDWR)                = 3
...
open("testfile", O_RDONLY)              = 4
copy_file_range(4, [0], 3, [0], 134217728, 0) = 0
+++ exited with 0 +++

so can you help me understand what bug you're fixing?

-Eric

> if argument of option -f is "-", use current file->fd as fd_in
> 
> Usage:
>   xfs_io -c 'copy_range -f -' some_file
> 
> Signed-off-by: Jianhong Yin <yin-jianhong@163.com>
> ---
>  io/copy_file_range.c | 27 ++++++++++++++++++---------
>  1 file changed, 18 insertions(+), 9 deletions(-)
> 
> diff --git a/io/copy_file_range.c b/io/copy_file_range.c
> index b7b9fd88..2dde8a31 100644
> --- a/io/copy_file_range.c
> +++ b/io/copy_file_range.c
> @@ -28,6 +28,7 @@ copy_range_help(void)
>                            at position 0\n\
>   'copy_range -f 2' - copies all bytes from open file 2 into the current open file\n\
>                            at position 0\n\
> + 'copy_range -f -' - copies all bytes from current open file append the current open file\n\
>  "));
>  }
>  
> @@ -114,11 +115,15 @@ copy_range_f(int argc, char **argv)
>  			}
>  			break;
>  		case 'f':
> -			src_file_nr = atoi(argv[1]);
> -			if (src_file_nr < 0 || src_file_nr >= filecount) {
> -				printf(_("file value %d is out of range (0-%d)\n"),
> -					src_file_nr, filecount - 1);
> -				return 0;
> +			if (strcmp(argv[1], "-") == 0)
> +				src_file_nr = (file - &filetable[0]) / sizeof(fileio_t);
> +			else {
> +				src_file_nr = atoi(argv[1]);
> +				if (src_file_nr < 0 || src_file_nr >= filecount) {
> +					printf(_("file value %d is out of range (0-%d)\n"),
> +						src_file_nr, filecount - 1);
> +					return 0;
> +				}
>  			}
>  			/* Expect no src_path arg */
>  			src_path_arg = 0;
> @@ -147,10 +152,14 @@ copy_range_f(int argc, char **argv)
>  		}
>  		len = sz;
>  
> -		ret = copy_dst_truncate();
> -		if (ret < 0) {
> -			ret = 1;
> -			goto out;
> +		if (fd != file->fd) {
> +			ret = copy_dst_truncate();
> +			if (ret < 0) {
> +				ret = 1;
> +				goto out;
> +			}
> +		} else {
> +			dst = sz;
>  		}
>  	}
>  
>
Jianhong.Yin Sept. 4, 2019, 3:24 a.m. UTC | #2
At 2019-09-04 01:54:21, "Eric Sandeen" <sandeen@redhat.com> wrote:
>On 9/3/19 6:19 AM, Jianhong.Yin wrote:
>> Related bug:
>>   copy_file_range return "Invalid argument" when copy in the same file
>>   https://bugzilla.kernel.org/show_bug.cgi?id=202935
>
>that's a CIFS bug though, not related to how xfs_io operates, correct?

Hi Eric

that's right, I thought that the condition to reproduce the bug must be fd_in == fd_out.
but now I know that's not correct.  src_file == dst_file is enough.


but there's a little problem, if exec follow command , will truncate src_file
   # xfs_io -c "copy_range testfile" testfile
it's not expected, will send new patch to fix it. if you agree

Jianhong

>
>What is the failing xfs_io case?  Because this seems to work fine here:
>
># fallocate -l 128m testfile
># strace -eopen,copy_file_range xfs_io -c "copy_range -s 1m -d 8m -l 2m testfile" testfile
>...
>open("testfile", O_RDWR)                = 3
>...
>open("testfile", O_RDONLY)              = 4
>copy_file_range(4, [1048576], 3, [8388608], 2097152, 0) = 2097152
>+++ exited with 0 +++
>
>this works too:
>
># strace -eopen,copy_file_range xfs_io -c "copy_range testfile" testfile
>...
>open("testfile", O_RDWR)                = 3
>...
>open("testfile", O_RDONLY)              = 4
>copy_file_range(4, [0], 3, [0], 134217728, 0) = 0
>+++ exited with 0 +++
>
>so can you help me understand what bug you're fixing?
>
>-Eric
>
>> if argument of option -f is "-", use current file->fd as fd_in
>> 
>> Usage:
>>   xfs_io -c 'copy_range -f -' some_file
>> 
>> Signed-off-by: Jianhong Yin <yin-jianhong@163.com>
>> ---
>>  io/copy_file_range.c | 27 ++++++++++++++++++---------
>>  1 file changed, 18 insertions(+), 9 deletions(-)
>> 
>> diff --git a/io/copy_file_range.c b/io/copy_file_range.c
>> index b7b9fd88..2dde8a31 100644
>> --- a/io/copy_file_range.c
>> +++ b/io/copy_file_range.c
>> @@ -28,6 +28,7 @@ copy_range_help(void)
>>                            at position 0\n\
>>   'copy_range -f 2' - copies all bytes from open file 2 into the current open file\n\
>>                            at position 0\n\
>> + 'copy_range -f -' - copies all bytes from current open file append the current open file\n\
>>  "));
>>  }
>>  
>> @@ -114,11 +115,15 @@ copy_range_f(int argc, char **argv)
>>  			}
>>  			break;
>>  		case 'f':
>> -			src_file_nr = atoi(argv[1]);
>> -			if (src_file_nr < 0 || src_file_nr >= filecount) {
>> -				printf(_("file value %d is out of range (0-%d)\n"),
>> -					src_file_nr, filecount - 1);
>> -				return 0;
>> +			if (strcmp(argv[1], "-") == 0)
>> +				src_file_nr = (file - &filetable[0]) / sizeof(fileio_t);
>> +			else {
>> +				src_file_nr = atoi(argv[1]);
>> +				if (src_file_nr < 0 || src_file_nr >= filecount) {
>> +					printf(_("file value %d is out of range (0-%d)\n"),
>> +						src_file_nr, filecount - 1);
>> +					return 0;
>> +				}
>>  			}
>>  			/* Expect no src_path arg */
>>  			src_path_arg = 0;
>> @@ -147,10 +152,14 @@ copy_range_f(int argc, char **argv)
>>  		}
>>  		len = sz;
>>  
>> -		ret = copy_dst_truncate();
>> -		if (ret < 0) {
>> -			ret = 1;
>> -			goto out;
>> +		if (fd != file->fd) {
>> +			ret = copy_dst_truncate();
>> +			if (ret < 0) {
>> +				ret = 1;
>> +				goto out;
>> +			}
>> +		} else {
>> +			dst = sz;
>>  		}
>>  	}
>>  
>>

Patch
diff mbox series

diff --git a/io/copy_file_range.c b/io/copy_file_range.c
index b7b9fd88..2dde8a31 100644
--- a/io/copy_file_range.c
+++ b/io/copy_file_range.c
@@ -28,6 +28,7 @@  copy_range_help(void)
                           at position 0\n\
  'copy_range -f 2' - copies all bytes from open file 2 into the current open file\n\
                           at position 0\n\
+ 'copy_range -f -' - copies all bytes from current open file append the current open file\n\
 "));
 }
 
@@ -114,11 +115,15 @@  copy_range_f(int argc, char **argv)
 			}
 			break;
 		case 'f':
-			src_file_nr = atoi(argv[1]);
-			if (src_file_nr < 0 || src_file_nr >= filecount) {
-				printf(_("file value %d is out of range (0-%d)\n"),
-					src_file_nr, filecount - 1);
-				return 0;
+			if (strcmp(argv[1], "-") == 0)
+				src_file_nr = (file - &filetable[0]) / sizeof(fileio_t);
+			else {
+				src_file_nr = atoi(argv[1]);
+				if (src_file_nr < 0 || src_file_nr >= filecount) {
+					printf(_("file value %d is out of range (0-%d)\n"),
+						src_file_nr, filecount - 1);
+					return 0;
+				}
 			}
 			/* Expect no src_path arg */
 			src_path_arg = 0;
@@ -147,10 +152,14 @@  copy_range_f(int argc, char **argv)
 		}
 		len = sz;
 
-		ret = copy_dst_truncate();
-		if (ret < 0) {
-			ret = 1;
-			goto out;
+		if (fd != file->fd) {
+			ret = copy_dst_truncate();
+			if (ret < 0) {
+				ret = 1;
+				goto out;
+			}
+		} else {
+			dst = sz;
 		}
 	}