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ioctl_fideduperange.2: srcfix 

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
This commit is contained in:
Michael Kerrisk 2016-06-08 12:24:06 +02:00
parent 2998d8b804
commit 990a64f7e3
1 changed files with 16 additions and 8 deletions
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24
man2/ioctl_fideduperange.2
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@ -33,10 +33,13 @@ system call can be used to make some of the data in the
file appear in the
.B dest_fd
file by sharing the underlying storage if the file data is identical
("deduplication"). This reduces storage consumption by allowing the filesystem
to store one shared copy of the data. If a file write should occur to a shared
("deduplication").
This reduces storage consumption by allowing the filesystem
to store one shared copy of the data.
If a file write should occur to a shared
region, the filesystem must ensure that the changes remain private to the file
being written. This behavior is commonly referred to as "copy on write".
being written.
This behavior is commonly referred to as "copy on write".
This ioctl performs the "compare and share if identical" operation on up to
.IR src_length
@ -66,7 +69,8 @@ The fields
must be zero.
Destinations for the deduplication operation are conveyed in the array at the
end of the structure. The number of destinations is given in
end of the structure.
The number of destinations is given in
.IR dest_count ",
and the destination information is conveyed in the following form:
@ -126,8 +130,10 @@ regions in directories.
.B EINVAL
The filesystem does not support deduplicating the ranges of the given files.
This error can also appear if either file descriptor represents a device, fifo,
or socket. Disk filesystems generally require the offset and length arguments
to be aligned to the fundamental block size. Neither btrfs nor XFS support
or socket.
Disk filesystems generally require the offset and length arguments
to be aligned to the fundamental block size.
Neither btrfs nor XFS support
overlapping deduplication ranges in the same file.
.TP
.B EBADF
@ -144,7 +150,8 @@ resides on does not support deduplication.
is immutable.
.TP
.B ETXTBSY
One of the files is a swap file. Swap files cannot share storage.
One of the files is a swap file.
Swap files cannot share storage.
.TP
.B EOPNOTSUPP
This can appear if the filesystem does not support deduplicating either file
@ -159,7 +166,8 @@ Some filesystems may limit the amount of data that can be deduplicated in a
single call.
.SH CONFORMING TO
This API is Linux-specific. This ioctl was previously known as
This API is Linux-specific.
This ioctl was previously known as
.B BTRFS_IOC_FILE_EXTENT_SAME
and was private to btrfs.
.fi