diff options
Diffstat (limited to 'sys/boot/i386/zfsboot/zfsldr.S')
| -rw-r--r-- | sys/boot/i386/zfsboot/zfsldr.S | 65 |
1 files changed, 41 insertions, 24 deletions
diff --git a/sys/boot/i386/zfsboot/zfsldr.S b/sys/boot/i386/zfsboot/zfsldr.S index b8be28265fc2..3e85e27aa38c 100644 --- a/sys/boot/i386/zfsboot/zfsldr.S +++ b/sys/boot/i386/zfsboot/zfsldr.S @@ -32,8 +32,11 @@ /* Misc. Constants */ .set SIZ_PAG,0x1000 # Page size .set SIZ_SEC,0x200 # Sector size - - .set NSECT,0x80 + .set COPY_BLKS,0x8 # Number of blocks + # to copy for boot2 + .set COPY_BLK_SZ,0x8000 # Copy in 32k blocks; must be + # a multiple of 16 bytes + .set NSECT,(COPY_BLK_SZ / SIZ_SEC * COPY_BLKS) .globl start .code16 @@ -88,12 +91,12 @@ main.3: add $0x10,%si # Next entry /* * Ok, we have a slice and drive in %dx now, so use that to locate and * load boot2. %si references the start of the slice we are looking - * for, so go ahead and load up the 128 sectors starting at sector 1024 - * (i.e. after the two vdev labels). We don't have do anything fancy - * here to allow for an extra copy of boot1 and a partition table - * (compare to this section of the UFS bootstrap) so we just load it - * all at 0x9000. The first part of boot2 is BTX, which wants to run - * at 0x9000. The boot2.bin binary starts right after the end of BTX, + * for, so go ahead and load up the COPY_BLKS*COPY_BLK_SZ/SIZ_SEC sectors + * starting at sector 1024 (i.e. after the two vdev labels). We don't + * have do anything fancy here to allow for an extra copy of boot1 and + * a partition table (compare to this section of the UFS bootstrap) so we + * just load it all at 0x9000. The first part of boot2 is BTX, which wants + * to run at 0x9000. The boot2.bin binary starts right after the end of BTX, * so we have to figure out where the start of it is and then move the * binary to 0xc000. Normally, BTX clients start at MEM_USR, or 0xa000, * but when we use btxld to create zfsboot2, we use an entry point of @@ -116,23 +119,37 @@ main.6: pushal # Save params incl %eax # Advance to add $SIZ_SEC,%ebx # next sector loop main.6 # If not last, read another - mov MEM_BTX+0xa,%bx # Get BTX length - mov $NSECT*SIZ_SEC-1,%di # Size of load area (less one) - mov %di,%si # End of load area, 0x9000 rel - sub %bx,%di # End of client, 0xc000 rel - mov %di,%cx # Size of - inc %cx # client - mov $(MEM_BTX)>>4,%dx # Segment - mov %dx,%ds # addressing 0x9000 - mov $(MEM_USR+2*SIZ_PAG)>>4,%dx # Segment - mov %dx,%es # addressing 0xc000 - std # Move with decrement - rep # Relocate - movsb # client + + mov $MEM_BTX,%bx # BTX + mov 0xa(%bx),%si # Get BTX length and set + add %bx,%si # %si to start of boot2 + dec %si # Set %ds:%si to point at the + mov %si,%ax # last byte we want to copy + shr $4,%ax # from boot2, with %si made as + add $(COPY_BLKS*COPY_BLK_SZ/16),%ax # small as possible. + and $0xf,%si # + mov %ax,%ds # + mov $(MEM_USR+2*SIZ_PAG)/16,%ax # Set %es:(-1) to point at + add $(COPY_BLKS*COPY_BLK_SZ/16),%ax # the last byte we + mov %ax,%es # want to copy boot2 into. + mov $COPY_BLKS,%bx # Copy COPY_BLKS 32k blocks +copyloop: + add $COPY_BLK_SZ,%si # Adjust %ds:%si to point at + mov %ds,%ax # the end of the next 32k to + sub $COPY_BLK_SZ/16,%ax # copy from boot2 + mov %ax,%ds + mov $COPY_BLK_SZ-1,%di # Adjust %es:%di to point at + mov %es,%ax # the end of the next 32k into + sub $COPY_BLK_SZ/16,%ax # which we want boot2 copied + mov %ax,%es + mov $COPY_BLK_SZ,%cx # Copy 32k + std + rep movsb + dec %bx + jnz copyloop + mov %cx,%ds # Reset %ds and %es + mov %cx,%es cld # Back to increment - xor %dx,%dx # Back - mov %ds,%dx # to zero - mov %dx,%es # segment /* * Enable A20 so we can access memory above 1 meg. |