Author: imp Date: Tue May 29 03:58:29 2018 New Revision: 334310 URL: https://svnweb.freebsd.org/changeset/base/334310
Log: Teach ufs_module.c about bsd labels and probe 'a' partition. If the check for a UFS partition at offset 0 on the disk fails, check to see if there's a BSD disklabel at block 1 (standard) or at offset 512 (install images assume 512 sector size). If found, probe for UFS on the 'a' partition. This fixes UEFI booting images from a BSD labeled MBR slice when the 'a' partiton isn't at offset 0. This is a stop-gap fix since we plan on removing boot1.efi in FreeBSD 12. We can't easily do that for 11.2, however, hence the short MFC window. Tested by: emaste@ MFC After: 3 days Sponsored by: Netflix Differential Revision: https://reviews.freebsd.org/D15598 Modified: head/stand/efi/boot1/boot_module.h head/stand/efi/boot1/ufs_module.c Modified: head/stand/efi/boot1/boot_module.h ============================================================================== --- head/stand/efi/boot1/boot_module.h Tue May 29 03:19:56 2018 (r334309) +++ head/stand/efi/boot1/boot_module.h Tue May 29 03:58:29 2018 (r334310) @@ -50,6 +50,7 @@ typedef struct dev_info EFI_DEVICE_PATH *devpath; EFI_HANDLE *devhandle; void *devdata; + uint64_t partoff; BOOLEAN preferred; struct dev_info *next; } dev_info_t; Modified: head/stand/efi/boot1/ufs_module.c ============================================================================== --- head/stand/efi/boot1/ufs_module.c Tue May 29 03:19:56 2018 (r334309) +++ head/stand/efi/boot1/ufs_module.c Tue May 29 03:58:29 2018 (r334310) @@ -36,10 +36,14 @@ #include <stdbool.h> #include <sys/cdefs.h> #include <sys/param.h> +#include <sys/disk/bsd.h> #include <efi.h> #include "boot_module.h" +#define BSD_LABEL_BUFFER 8192 +#define BSD_LABEL_OFFSET DEV_BSIZE + static dev_info_t *devinfo; static dev_info_t *devices; @@ -49,6 +53,7 @@ dskread(void *buf, uint64_t lba, int nblk) int size; EFI_STATUS status; + lba += devinfo->partoff; lba = lba / (devinfo->dev->Media->BlockSize / DEV_BSIZE); size = nblk * DEV_BSIZE; @@ -73,11 +78,50 @@ static struct dmadat __dmadat; static int init_dev(dev_info_t* dev) { + char buffer[BSD_LABEL_BUFFER]; + struct disklabel *dl; + uint64_t bs; + int ok; devinfo = dev; dmadat = &__dmadat; - return fsread(0, NULL, 0); + /* + * First try offset 0. This is the typical GPT case where we have no + * further partitioning (as well as the degenerate MBR case where + * the bsdlabel has a 0 offset). + */ + devinfo->partoff = 0; + ok = fsread(0, NULL, 0); + if (ok >= 0) + return (ok); + + /* + * Next, we look for a bsdlabel. This is technically located in sector + * 1. For 4k sectors, this offset is 4096, for 512b sectors it's + * 512. However, we have to fall back to 512 here because we create + * images that assume 512 byte blocks, but these can be put on devices + * who have 4k (or other) block sizes. If there's a crazy block size, we + * skip the 'at one sector' and go stright to checking at 512 bytes. + * There are other offsets that are historic, but we don't probe those + * since they were never used for MBR disks on FreeBSD on systems that + * could boot UEFI. UEFI is little endian only, as are BSD labels. We + * will retry fsread(0) only if there's a label found with a non-zero + * offset. + */ + if (dskread(buffer, 0, BSD_LABEL_BUFFER / DEV_BSIZE) != 0) + return (-1); + dl = NULL; + bs = devinfo->dev->Media->BlockSize; + if (bs != 0 && bs <= BSD_LABEL_BUFFER / 2) + dl = (struct disklabel *)&buffer[bs]; + if (dl == NULL || dl->d_magic != BSD_MAGIC || dl->d_magic2 != BSD_MAGIC) + dl = (struct disklabel *)&buffer[BSD_LABEL_OFFSET]; + if (dl->d_magic != BSD_MAGIC || dl->d_magic2 != BSD_MAGIC || + dl->d_partitions[0].p_offset == 0) + return (-1); + devinfo->partoff = dl->d_partitions[0].p_offset; + return (fsread(0, NULL, 0)); } static EFI_STATUS _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
