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auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.197, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: kwolf@redhat.com, Peter Maydell , qemu-block@nongnu.org, qemu-devel@nongnu.org, Joelle van Dyne , Paolo Bonzini , Warner Losh Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Jun 15, 2021 at 06:50:57PM +0200, Max Reitz wrote: > On 03.06.21 15:37, Paolo Bonzini wrote: > > From: Joelle van Dyne > > > > iOS hosts do not have these defined so we fallback to the > > default behaviour. > > > > Co-authored-by: Warner Losh > > Reviewed-by: Peter Maydell > > Signed-off-by: Joelle van Dyne > > Message-Id: <20210315180341.31638-4-j@getutm.app> > > Signed-off-by: Paolo Bonzini > > --- > > block/file-posix.c | 21 +++++++++------------ > > 1 file changed, 9 insertions(+), 12 deletions(-) > > > > diff --git a/block/file-posix.c b/block/file-posix.c > > index 5821e1afed..4e2f7cf508 100644 > > --- a/block/file-posix.c > > +++ b/block/file-posix.c > > @@ -2322,8 +2322,11 @@ static int64_t raw_getlength(BlockDriverState *bs) > > again: > > #endif > > if (!fstat(fd, &sb) && (S_IFCHR & sb.st_mode)) { > > + size = 0; > > #ifdef DIOCGMEDIASIZE > > - if (ioctl(fd, DIOCGMEDIASIZE, (off_t *)&size)) > > + if (ioctl(fd, DIOCGMEDIASIZE, (off_t *)&size)) { > > Pre-existing, but I feel compelled to express my unease about this cast. We set -D_FILE_OFFSET_BITS=64, so IIUC, off_t should be 64-bits on both 32 and 64 bit build hosts. IIUC, it is defined to be a signed integer. So while off_t may not have the same typedef as int64_t, it should be the same size and signedness. I expect we have other code with this same assumption about off-t/int64_t interchangeability. We could assert sizeof(int64_t) == sizeof(off_t) in a header somewhere if we want to be super paranoid. > > > + size = 0; > > + } > > #elif defined(DIOCGPART) > > { > > struct partinfo pi; > > @@ -2332,9 +2335,7 @@ again: > > else > > size = 0; > > } > > - if (size == 0) > > -#endif > > -#if defined(__APPLE__) && defined(__MACH__) > > +#elif defined(DKIOCGETBLOCKCOUNT) && defined(DKIOCGETBLOCKSIZE) > > As far a I can tell, before this patch, if the DIOCGMEDIASIZE ioctl failed, > we fell back to this DKIOCGETBLOCKCOUNT/SIZE block (if compiled in). Now > this is an #elif and so will not be used if DIOCGMEDIASIZE was defined. Is > that intentional? > > This may be fine, and apart from that, this patch looks good to me, but this > change in behavior wasn’t mentioned in the commit message, hence me asking. > > > { > > uint64_t sectors = 0; > > uint32_t sector_size = 0; > > @@ -2342,19 +2343,15 @@ again: > > if (ioctl(fd, DKIOCGETBLOCKCOUNT, §ors) == 0 > > && ioctl(fd, DKIOCGETBLOCKSIZE, §or_size) == 0) { > > size = sectors * sector_size; > > - } else { > > - size = lseek(fd, 0LL, SEEK_END); > > - if (size < 0) { > > - return -errno; > > - } > > } > > } > > -#else > > - size = lseek(fd, 0LL, SEEK_END); > > +#endif > > + if (size == 0) { > > + size = lseek(fd, 0LL, SEEK_END); > > + } > > if (size < 0) { > > return -errno; > > } > > -#endif > > #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) > > switch(s->type) { > > case FTYPE_CD: > > Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|