On 03/19/2017 11:45 PM, Theodore Ts'o wrote:
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.
I checked that DKIOCGETBLOCKSIZE and DKIOCGETBLOCKCOUNT are both available in file xnu/bsd/sys/disk.h from version 10.1 to 10.12.
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?
There is no definition of DIOCGSECTORSIZE for Mac OS X. Seems like, it exist only for FreeBSD. Not sure about alignment restriction for Direct I/O, but for for Intel based Mac's the 4k page size will have place.
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 <thisisadrgreenthumb@xxxxxxxxx> --- 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
