As soon as a mapping is unlinked from the list, there are no further
references to it, so it should be freed. If it not unlinked,
update the start address and length.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
The code assumes sorted mappings in descending address order. When
splitting a mapping, insert the new part next to the current mapping.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
Currently each allocation creates a new mapping. Readding the mapping
as free memory (EFI_CONVENTIONAL_MEMORY) potentially allows to hand out
an existing mapping, thus limiting the number of mapping descriptors in
the memory map.
Mitigates a problem with current (4.8rc7) linux kernels when doing an
efi_get_memory map, resulting in an infinite loop. Space for the memory
map is reserved with allocate_pool (implicitly creating a new mapping) and
filled. If there is insufficient slack space (8 entries) in the map, the
space is freed and a new round is started, with space for one more entry.
As each round increases requirement and allocation by exactly one, there
is never enough slack space. (At least 32 entries are allocated, so as
long as there are less than 24 entries, there is enough slack).
Earlier kernels reserved no slack, and did less allocations, so this
problem was not visible.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
We need a functional free_pool implementation, as otherwise each
allocate_pool causes growth of the memory descriptor table.
Different to free_pages, free_pool does not provide the size for the
to be freed allocation, thus we have to track the size ourselves.
As the only EFI requirement for pool allocation is an alignment of
8 bytes, we can keep allocating a range using the page allocator,
reserve the first 8 bytes for our bookkeeping and hand out the
remainder to the caller. This saves us from having to use any
independent data structures for tracking.
To simplify the conversion between pool allocations and the corresponding
page allocation, we create an auxiliary struct efi_pool_allocation.
Given the allocation size free_pool size can handoff freeing the page
range, which was indirectly allocated by a call to allocate_pool,
to free_pages.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
We currently handle efi_allocate_pool() in our boot time service
file. In the following patch, pool allocation will receive additional
internal semantics that we should preserve inside efi_memory.c instead.
As foundation for those changes, split the function into an externally
facing efi_allocate_pool_ext() for use by payloads and an internal helper
efi_allocate_pool() in efi_memory.c that handles the actual allocation.
While at it, change the magic 0xfff / 12 constants to the more obvious
EFI_PAGE_MASK/SHIFT defines.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
The current efi_get_memory_map() function overwrites the map_size
property before reading its value. That way the sanity check whether our
memory map fits into the given array always succeeds, potentially
overwriting arbitrary payload memory.
This patch moves the property update write after its sanity check, so
that the check actually verifies the correct value.
So far this has not triggered any known bugs, but we're better off safe
than sorry.
If the buffer is to small, the returned memory_map_size indicates the
required size to the caller.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
In 74c16acce3 the return values where
changed, but the description was kept.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
Provide version of struct efi_mem_desc in efi_get_memory_map().
EFI_BOOT_SERVICES.GetMemoryMap() in UEFI specification v2.6 defines
memory descriptor version to 1. Linux kernel also expects descriptor
version to be 1 and prints following warning during boot if its not:
Unexpected EFI_MEMORY_DESCRIPTOR version 0
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@gmail.com>
Tracing the arguments has been helpful for pinpointing overflows.
Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
When a payload calls our memory allocator with the exact address hint, we
happily allocate memory from completely unpopulated regions. Payloads however
expect this to only succeed if they would be allocating from free conventional
memory.
This patch makes the logic behind those checks a bit more obvious and ensures
that we always allocate from known good free conventional memory regions if we
want to allocate ram.
Reported-by: Jonathan Gray <jsg@jsg.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
We introduced special "DEBUG_EFI" defines when the efi loader
support was new. After giving it a bit of thought, turns out
we really didn't have to - the normal #define DEBUG infrastructure
works well enough for efi loader as well.
So this patch switches to the common debug() and #define DEBUG
way of printing debug information.
Signed-off-by: Alexander Graf <agraf@suse.de>
Some hardware that is supported by U-Boot can not handle DMA above 32bits.
For these systems, we need to come up with a way to expose the disk interface
in a safe way.
This patch implements EFI specific bounce buffers. For non-EFI cases, this
apparently was no issue so far, since we can just define our environment
variables conveniently.
Signed-off-by: Alexander Graf <agraf@suse.de>
jetson-tk1 has 2 GB of RAM at 0x80000000, causing gd->ram_top to be zero.
Handle this by either avoiding ram_top or by using the same type as
ram_top to reverse the overflow effect.
Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
The EFI memory map does not need to be in a strict order, but 32bit
grub2 does expect it to be ascending. If it's not, it may try to
allocate memory inside the U-Boot data memory region.
We already sort the memory map in descending order, so let's just
reverse it when we pass it to a payload.
Signed-off-by: Alexander Graf <agraf@suse.de>
Tested-by: Andreas Färber <afaerber@suse.de>
Some EFI applications (grub2) expect that an allocation always returns
the highest available memory address for the given size.
Without this, we may run into situations where the initrd gets allocated
at a lower address than the kernel.
This patch fixes booting in such situations for me.
Signed-off-by: Alexander Graf <agraf@suse.de>
The EFI loader needs to maintain views of memory - general system memory
windows as well as used locations inside those and potential runtime service
MMIO windows.
To manage all of these, add a few helpers that maintain an internal
representation of the map the similar to how the EFI API later on reports
it to the application.
For allocations, the scheme is very simple. We basically allow allocations
to replace chunks of previously done maps, so that a new LOADER_DATA
allocation for example can remove a piece of the RAM map. When no specific
address is given, we just take the highest possible address in the lowest
RAM map that fits the allocation size.
Signed-off-by: Alexander Graf <agraf@suse.de>
Tested-by: Simon Glass <sjg@chromium.org>
Stefan Brüns
Mian Yousaf Kaukab
Andreas Färber
Alexander Graf