On Tue, Feb 28, 2017 at 04:33:14PM +0100, Patrick Wildt wrote: > On Wed, Mar 01, 2017 at 12:17:02AM +0900, YASUOKA Masahiko wrote: > > Hi, > > > > On Tue, 28 Feb 2017 15:16:58 +0100 > > Patrick Wildt <[email protected]> wrote: > > > On Tue, Feb 28, 2017 at 10:41:21PM +0900, YASUOKA Masahiko wrote: > > >> On Mon, 27 Feb 2017 11:10:31 +0100 > > >> Patrick Wildt <[email protected]> wrote: > > >> > I'm surprised this didn't come up earlier, but I think the for-loop is > > >> > a > > >> > bit wrong. What the code is supposed to be doing is going over each > > >> > device path node for the loaded image, which is supposed to be the path > > >> > to the device that efiboot was loaded from, and check for a node that > > >> > is a medium (as in hard drive, cdrom) and look for a hard drive. > > >> > > >> Yes, you are right it's wrong. > > >> > > >> > As it turns out, the code would actually skip all device paths that > > >> > are mediums and instead match on all non-media types. It's surprising > > >> > to me that this seems to work for people. > > >> > > > >> > On Qemu and VMware the first node in the device path is ACPI (2) with > > >> > subtype (1). Interestingly, the hard drive subtype in the media type > > >> > has the subtype (1) as well. So that might be a reason it did work. > > >> > > >> As far as my test on QEMU and VAIO, the first node is ACPI and subtype > > >> is 1. > > >> > > >> But we had another bug, > > >> > > >> 87 if (status == EFI_SUCCESS) { > > >> 88 for (dp = dp0; !IsDevicePathEnd(dp); > > >> 89 dp = NextDevicePathNode(dp)) { > > >> 90 if (DevicePathType(dp) == > > >> MEDIA_DEVICE_PATH) > > >> 91 continue; > > >> 92 if (DevicePathSubType(dp) == > > >> MEDIA_HARDDRIVE_DP) { > > >> 93 bios_bootdev = 0x80; > > >> 94 efi_bootdp = dp; > > >> 95 break; > > >> 96 } > > >> 97 break; > > >> 98 } > > >> 99 } > > >> > > >> if we fix the bug at #90, at #94 efi_bootdp will not become the first > > >> dp node(dp0). Then efi_diskprobe() will fail to reorder hd? properly > > >> since the function assumes efi_bootdp is the first dp node. > > >> > > >> So I'd like to commit the diff below. > > > > > > First of all, I've been having a look at supporting CDROMs in efiboot > > > and saw that FreeBSD has a nice "devpath.c" file which implements a few > > > good helpers. I've been using efi_devpath_match(), efi_devpath_trim() > > > and efi_devpath_last_node(). Those have been particularly helpful and > > > simplify some code. I wonder if it would make sense to pull that one > > > in instead of writing another completely new implementation of tha same > > > thing. > > > > > >> diff --git a/sys/arch/amd64/stand/efiboot/efiboot.c > > >> b/sys/arch/amd64/stand/efiboot/efiboot.c > > >> index 1903862d271..f82ea34f66e 100644 > > >> --- a/sys/arch/amd64/stand/efiboot/efiboot.c > > >> +++ b/sys/arch/amd64/stand/efiboot/efiboot.c > > >> @@ -41,7 +41,8 @@ > > >> EFI_SYSTEM_TABLE *ST; > > >> EFI_BOOT_SERVICES *BS; > > >> EFI_RUNTIME_SERVICES *RS; > > >> -EFI_HANDLE IH, efi_bootdp = NULL; > > >> +EFI_HANDLE IH; > > >> +EFI_DEVICE_PATH *efi_bootdp = NULL; > > >> EFI_PHYSICAL_ADDRESS heap; > > >> EFI_LOADED_IMAGE *loadedImage; > > >> UINTN heapsiz = 1 * 1024 * 1024; > > >> @@ -51,6 +52,7 @@ static EFI_GUID blkio_guid = > > >> BLOCK_IO_PROTOCOL; > > >> static EFI_GUID devp_guid = DEVICE_PATH_PROTOCOL; > > >> u_long efi_loadaddr; > > >> > > >> +static int efi_device_path_cmp(EFI_DEVICE_PATH *, EFI_DEVICE_PATH > > >> *, int); > > >> static void efi_heap_init(void); > > >> static void efi_memprobe_internal(void); > > >> static void efi_video_init(void); > > >> @@ -87,14 +89,12 @@ efi_main(EFI_HANDLE image, EFI_SYSTEM_TABLE *systab) > > >> if (status == EFI_SUCCESS) { > > >> for (dp = dp0; !IsDevicePathEnd(dp); > > >> dp = NextDevicePathNode(dp)) { > > >> - if (DevicePathType(dp) == MEDIA_DEVICE_PATH) > > >> - continue; > > >> - if (DevicePathSubType(dp) == > > >> MEDIA_HARDDRIVE_DP) { > > >> + if (DevicePathType(dp) == MEDIA_DEVICE_PATH && > > >> + DevicePathSubType(dp) == > > >> MEDIA_HARDDRIVE_DP) { > > >> bios_bootdev = 0x80; > > >> - efi_bootdp = dp; > > >> + efi_bootdp = dp0; > > > > > > This part makes sense to me. > > > > > >> break; > > >> } > > >> - break; > > >> } > > >> } > > >> > > >> @@ -166,7 +166,7 @@ efi_diskprobe(void) > > >> EFI_BLOCK_IO *blkio; > > >> EFI_BLOCK_IO_MEDIA *media; > > >> struct diskinfo *di; > > >> - EFI_DEVICE_PATH *dp, *bp; > > >> + EFI_DEVICE_PATH *dp; > > >> > > >> TAILQ_INIT(&efi_disklist); > > >> > > >> @@ -193,23 +193,14 @@ efi_diskprobe(void) > > >> di = alloc(sizeof(struct diskinfo)); > > >> efid_init(di, blkio); > > >> > > >> - if (efi_bootdp == NULL) > > >> - goto next; > > >> - status = EFI_CALL(BS->HandleProtocol, handles[i], > > >> &devp_guid, > > >> - (void **)&dp); > > >> - if (EFI_ERROR(status)) > > >> - goto next; > > >> - bp = efi_bootdp; > > >> - while (1) { > > >> - if (IsDevicePathEnd(dp)) { > > >> + if (efi_bootdp != NULL) { > > >> + status = EFI_CALL(BS->HandleProtocol, > > >> handles[i], &devp_guid, > > >> + (void **)&dp); > > >> + if (EFI_ERROR(status)) > > >> + goto next; > > >> + if (efi_device_path_cmp(efi_bootdp, dp, > > >> MESSAGING_DEVICE_PATH) > > >> + == 0) > > > > > > This part makes sense to me as well. > > > > > >> bootdev = 1; > > >> - break; > > >> - } > > >> - if (memcmp(dp, bp, sizeof(EFI_DEVICE_PATH)) != > > >> 0 || > > >> - memcmp(dp, bp, DevicePathNodeLength(dp)) != > > >> 0) > > >> - break; > > >> - dp = NextDevicePathNode(dp); > > >> - bp = NextDevicePathNode(bp); > > >> } > > >> next: > > >> if (bootdev) > > >> @@ -221,6 +212,35 @@ next: > > >> free(handles, sz); > > >> } > > >> > > >> +static int > > >> +efi_device_path_cmp(EFI_DEVICE_PATH *dpa, EFI_DEVICE_PATH *dpb, int > > >> dptype) > > >> +{ > > >> + int cmp; > > >> + EFI_DEVICE_PATH *dp, *dpt_a = NULL, *dpt_b = NULL; > > >> + > > >> + for (dp = dpa; !IsDevicePathEnd(dp); dp = > > >> NextDevicePathNode(dp)) { > > >> + if (DevicePathType(dp) == dptype) { > > >> + dpt_a = dp; > > >> + break; > > >> + } > > >> + } > > >> + for (dp = dpb; !IsDevicePathEnd(dp); dp = > > >> NextDevicePathNode(dp)) { > > >> + if (DevicePathType(dp) == dptype) { > > >> + dpt_b = dp; > > >> + break; > > >> + } > > >> + } > > >> + > > >> + if (dpt_a && dpt_b) { > > >> + cmp = DevicePathNodeLength(dpt_a) - > > >> DevicePathNodeLength(dpt_b); > > >> + if (cmp) > > >> + return (cmp); > > >> + return (memcmp(dpt_a, dpt_b, > > >> DevicePathNodeLength(dpt_a))); > > >> + } > > >> + > > >> + return ((uintptr_t)dpt_a - (uintptr_t)dpt_b); > > >> +} > > > > > > I don't like this. Have a look at the FreeBSD implementation, it's > > > nicer sind you don't have to pass some device path type but instead > > > it does a full path comparison. > > > > How will you fix by efi_devpath_match()? > > > > AFAIK, we need to find the device path of the booted disk. (not the > > booted parition) So I belive "full path comparison" is not usable. > > > > --yasuoka > > > > I see the problem. The way people do it with hard drives and cdroms is > to trim/cut away the last node of the device path, because then you get > the device path to the entire device instead of just a subnode. Then > you can compare the pathes. >
Also that makes me wonder, if the device path is the one to the booted partition, wouldn't blkio point to the booted partition instead of the full device as well?
