There is a potential bug in __lmb_alloc_base where we subtract `size'
from the base address of a reserved region without checking whether
the subtraction could wrap around and produce a very large unsigned
value. In fact it probably isn't possible to hit the bug in practice
since it would only occur in the situation where we can't satisfy the
allocation request and there is a reserved region starting at 0.
This fixes the potential bug by breaking out of the loop when we get
to the point where the base of the reserved region is less than the
size requested. This also restructures the loop to be a bit easier to
follow.
The same logic got copied into lmb_alloc_nid_unreserved, so this makes
a similar change there. Here the bug is more likely to be hit because
the outer loop (in lmb_alloc_nid) goes through the memory regions in
increasing order rather than decreasing order as __lmb_alloc_base
does, and we are therefore more likely to hit the case where we are
testing against a reserved region with a base address of 0.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes no semantic changes. It fixes the whitespace and formatting
a bit, gets rid of a local DBG macro and uses the equivalent pr_debug
instead, and restructures one while loop that had a function call and
assignment in the condition to be a bit more readable. Some comments
about functions being called with relocation disabled were also removed
as they would just be confusing to most readers now that the code is
in lib/.
Signed-off-by: Paul Mackerras <paulus@samba.org>
A variant of lmb_alloc() that tries to allocate memory on a specified
NUMA node 'nid' but falls back to normal lmb_alloc() if that fails.
The caller provides a 'nid_range' function pointer which assists the
allocator. It is given args 'start', 'end', and pointer to integer
'this_nid'.
It places at 'this_nid' the NUMA node id that corresponds to 'start',
and returns the end address within 'start' to 'end' at which memory
assosciated with 'nid' ends.
This callback allows a platform to use lmb_alloc_nid() in just
about any context, even ones in which early_pfn_to_nid() might
not be working yet.
This function will be used by the NUMA setup code on sparc64, and also
it can be used by powerpc, replacing it's hand crafted
"careful_allocation()" function in arch/powerpc/mm/numa.c
If x86 ever converts it's NUMA support over to using the LMB helpers,
it can use this too as it has something entirely similar.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We introduced a bug in fixing lmb_add_region to handle an initial
region being non-zero. Before that fix it was impossible to insert a
region at the head of the list since the first region always started
at zero.
Now that its possible for the first region to be non-zero we need to
check to see if the new region should be added at the head and if so
actually add it.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert the lmb code to use u64 instead of unsigned long for physical
addresses and sizes. This is needed to support large amounts of RAM
on 32-bit systems that support 36-bit physical addressing.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If we add to an empty lmb region with a non-zero base we will not
coalesce the number of regions down to one. This causes problems on
ppc32 for the memory region as its assumed to only have one region.
We can fix this be easily specially casing the initial add to just
replace the dummy region.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We need to check lmb_add_region() for errors, it can run out
of regions etc.
Also, the size needs to be padded to the given alignment
or else the lmb.reserved regions don't get expanded and
instead we get tons of holes and eventually run out of
regions prematurely.
Signed-off-by: David S. Miller <davem@davemloft.net>
Paul Mackerras