Re: [Libguestfs] [PATCH v3 1/4] file: Avoid unsupported fallocate() calls

On Sun, Aug 19, 2018 at 01:13:05AM +0300, Nir Soffer wrote: > When using file systems not supporting ZERO_RANGE (e.g. NFS 4.2) or > block device on kernel < 4.9, we used to call fallocate() for every > zero, fail with EOPNOTSUPP, and fallback to manual zeroing. When > trimming, we used to try unsupported fallocate() on every call. > > Change file handle to remember if punching holes or zeroing range are > supported, and avoid unsupported calls. > > - zero changed to: > 1. If we can punch hole and may trim, try PUNCH_HOLE > 2. If we can zero range, try ZERO_RANGE > 3. Fall back to manual writing > > - trim changed to: > 1. If we can punch hole, try PUNCH_HOLE > 2. Succeed > --- > plugins/file/file.c | 80 ++++++++++++++++++++++++++++++--------------- > 1 file changed, 53 insertions(+), 27 deletions(-) > > diff --git a/plugins/file/file.c b/plugins/file/file.c > index 3bb4d17..5daab63 100644 > --- a/plugins/file/file.c > +++ b/plugins/file/file.c > @@ -33,6 +33,7 @@ > > #include <config.h> > > +#include <stdbool.h> > #include <stdio.h> > #include <stdlib.h> Can you put stdbook after stdlib for consistency with the other source files.

> #ifdef FALLOC_FL_ZERO_RANGE > - r = do_fallocate (h->fd, FALLOC_FL_ZERO_RANGE, offset, count); > - if (r == -1 && errno != EOPNOTSUPP) { > - nbdkit_error ("zero: %m"); > + if (h->can_zero_range) { > + r = do_fallocate (h->fd, FALLOC_FL_ZERO_RANGE, offset, count); > + if (r== 0) Spacing.

Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-builder quickly builds VMs from scratch http://libguestfs.org/virt-builder.1.html