summaryrefslogtreecommitdiff
path: root/lib/efi_loader/efi_memory.c
AgeCommit message (Collapse)Author
2016-10-18efi_loader: Do not leak memory when unlinking a mappingStefan Brüns
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>
2016-10-18efi_loader: Keep memory mapping sorted when splitting an entryStefan Brüns
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>
2016-10-18efi_loader: Readd freed pages to memory poolStefan Brüns
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>
2016-10-18efi_loader: Track size of pool allocations to allow freeingStefan Brüns
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>
2016-10-18efi_loader: Move efi_allocate_pool implementation to efi_memory.cStefan Brüns
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>
2016-10-18efi_loader: Fix memory map size check to avoid out-of-bounds accessStefan Brüns
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>
2016-10-18efi_loader: Update description of internal efi_mem_carve_outStefan Brüns
In 74c16acce30bb882ad5951829d8dafef8eea564c 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>
2016-09-07efi_loader: provide efi_mem_desc versionMian Yousaf Kaukab
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>
2016-07-22efi_loader: Add debug output for efi_add_memory_map()Andreas Färber
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>
2016-06-06efi_loader: Don't allocate from memory holesAlexander Graf
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>
2016-06-06efi_loader: Move to normal debug infrastructureAlexander Graf
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>
2016-05-27efi_loader: Add bounce buffer supportAlexander Graf
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>
2016-04-18efi_loader: Handle memory overflowsAndreas Färber
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>
2016-04-18efi_loader: Expose ascending efi memory mapAlexander Graf
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>
2016-04-01efi_loader: Always allocate the highest available addressAlexander Graf
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>
2016-03-15efi_loader: Implement memory allocation and mapAlexander Graf
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>