From mboxrd@z Thu Jan 1 00:00:00 1970 From: Theodore Ts'o Subject: Re: [PATCH] e2fsprogs: Apple Darwin, fix case of device with not 512 bytes block size Date: Sun, 19 Mar 2017 16:45:03 -0400 Message-ID: <20170319204503.kedk2x35xvceqocj@thunk.org> References: <20170319192926.GA3509@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-ext4@vger.kernel.org To: Fedor Uporov Return-path: Received: from imap.thunk.org ([74.207.234.97]:55524 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752386AbdCSVUA (ORCPT ); Sun, 19 Mar 2017 17:20:00 -0400 Content-Disposition: inline In-Reply-To: <20170319192926.GA3509@localhost.localdomain> Sender: linux-ext4-owner@vger.kernel.org List-ID: Thanks for the patch. Can you tell me how far back support for DKIOCGETBLOCKSIZE goes? i.e., is it worth adding a fallback if DKIOCGETBLOCKSIZE is not available? I suppose in the worst case we can fall back to using a binary search to find size of the device. Also, could I perhaps ask you to take a look at lib/ext2fs/getsectsize.c while you are at it? Does Mac OS X have support for DIOCGSECTORSIZE, and how does this related to DKIOCGETBLOCKSIZE? Do you know what Mac OS X's alignment restrictions are for Direct I/O? Many thanks for helping me improve Apple Darwin support for e2fsprogs! :-) - Ted On Sun, Mar 19, 2017 at 10:29:26PM +0300, Fedor Uporov wrote: > Signed-off-by: Fedor Uporov > --- > lib/blkid/getsize.c | 11 +++++++---- > lib/ext2fs/getsize.c | 9 ++++++--- > 2 files changed, 13 insertions(+), 7 deletions(-) > > diff --git a/lib/blkid/getsize.c b/lib/blkid/getsize.c > index 8e8eb4c..3d26338 100644 > --- a/lib/blkid/getsize.c > +++ b/lib/blkid/getsize.c > @@ -78,12 +78,15 @@ blkid_loff_t blkid_get_dev_size(int fd) > unsigned long long size64; > blkid_loff_t high, low; > > -#ifdef DKIOCGETBLOCKCOUNT /* For Apple Darwin */ > - if (ioctl(fd, DKIOCGETBLOCKCOUNT, &size64) >= 0) { > +#if defined DKIOCGETBLOCKCOUNT && defined DKIOCGETBLOCKSIZE /* For Apple Darwin */ > + unsigned int size; > + > + if (ioctl(fd, DKIOCGETBLOCKCOUNT, &size64) >= 0 && > + ioctl(fd, DKIOCGETBLOCKSIZE, &size) >= 0) { > if (sizeof(blkid_loff_t) < sizeof(unsigned long long) && > - (size64 << 9) > 0xFFFFFFFF) > + (size64 * size) > 0xFFFFFFFF) > return 0; /* EFBIG */ > - return (blkid_loff_t)size64 << 9; > + return (blkid_loff_t)size64 * size; > } > #endif > > diff --git a/lib/ext2fs/getsize.c b/lib/ext2fs/getsize.c > index 89c33d4..68480c6 100644 > --- a/lib/ext2fs/getsize.c > +++ b/lib/ext2fs/getsize.c > @@ -151,9 +151,12 @@ errcode_t ext2fs_get_device_size2(const char *file, int blocksize, > if (fd < 0) > return errno; > > -#ifdef DKIOCGETBLOCKCOUNT /* For Apple Darwin */ > - if (ioctl(fd, DKIOCGETBLOCKCOUNT, &size64) >= 0) { > - *retblocks = size64 / (blocksize / 512); > +#if defined DKIOCGETBLOCKCOUNT && defined DKIOCGETBLOCKSIZE /* For Apple Darwin */ > + unsigned int size; > + > + if (ioctl(fd, DKIOCGETBLOCKCOUNT, &size64) >= 0 && > + ioctl(fd, DKIOCGETBLOCKSIZE, &size) >= 0) { > + *retblocks = size64 * size / blocksize; > goto out; > } > #endif > -- > 2.1.4 >