The logic used in lmb_alloc() takes into consideration the existing
reserved regions, and ensures that the allocated region does not
overlap with any existing allocated regions. The lmb_reserve()
function is not doing any such checks -- the requested region might
overlap with an existing region. This also shows up with
lmb_alloc_addr() as this function ends up calling lmb_reserve().
Add a function which checks if the region requested is overlapping
with an existing reserved region, and allow for the reservation to
happen only if both the regions have LMB_NONE flag, which allows
re-requesting of the region. In any other scenario of an overlap, have
lmb_reserve() return -EEXIST, implying that the requested region is
already reserved.
Add corresponding test cases which check for overlapping reservation
requests made through lmb_reserve() and lmb_alloc_addr(). And while
here, fix some of the comments in the test function being touched.
Signed-off-by: Sughosh Ganu <sughosh.g...@linaro.org>
---
Changes since V1:
* Add documentation for the lmb_can_reserve_region() function.
* Add an additional test case where a new region is being added, and
the new region overlaps two different existing regions, with
mismatching flags.
* Some cleanup of comments in the lib_test_lmb_overlapping_reserve()
function.
lib/lmb.c | 36 ++++++++++++++++
test/lib/lmb.c | 114 +++++++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 146 insertions(+), 4 deletions(-)
diff --git a/lib/lmb.c b/lib/lmb.c
index 7ca44591e1d..d7d2c8c6dfd 100644
--- a/lib/lmb.c
+++ b/lib/lmb.c
@@ -595,6 +595,39 @@ static __maybe_unused void lmb_reserve_common_spl(void)
}
}
+/**
+ * lmb_can_reserve_region() - check if the region can be reserved
+ * @base: base address of region to be reserved
+ * @size: size of region to be reserved
+ * @flags: flag of the region to be reserved
+ *
+ * Go through all the reserved regions and ensure that the requested
+ * region does not overlap with any existing regions. An overlap is
+ * allowed only when the flag of the request region and the existing
+ * region is LMB_NONE.
+ *
+ * Return: true if region can be reserved, false otherwise
+ */
+static bool lmb_can_reserve_region(phys_addr_t base, phys_size_t size,
+ u32 flags)
+{
+ uint i;
+ struct lmb_region *lmb_reserved = lmb.used_mem.data;
+
+ for (i = 0; i < lmb.used_mem.count; i++) {
+ u32 rgnflags = lmb_reserved[i].flags;
+ phys_addr_t rgnbase = lmb_reserved[i].base;
+ phys_size_t rgnsize = lmb_reserved[i].size;
+
+ if (lmb_addrs_overlap(base, size, rgnbase, rgnsize)) {
+ if (flags != LMB_NONE || flags != rgnflags)
+ return false;
+ }
+ }
+
+ return true;
+}
+
void lmb_add_memory(void)
{
int i;
@@ -667,6 +700,9 @@ long lmb_reserve(phys_addr_t base, phys_size_t size, u32
flags)
long ret = 0;
struct alist *lmb_rgn_lst = &lmb.used_mem;
+ if (!lmb_can_reserve_region(base, size, flags))
+ return -EEXIST;
+
ret = lmb_add_region_flags(lmb_rgn_lst, base, size, flags);
if (ret)
return ret;
diff --git a/test/lib/lmb.c b/test/lib/lmb.c
index fcb5f1af532..24416e83491 100644
--- a/test/lib/lmb.c
+++ b/test/lib/lmb.c
@@ -471,17 +471,17 @@ static int lib_test_lmb_overlapping_reserve(struct
unit_test_state *uts)
ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 1, 0x40010000, 0x10000,
0, 0, 0, 0);
- /* allocate overlapping region should return the coalesced count */
+ /* allocate overlapping region */
ret = lmb_reserve(0x40011000, 0x10000, LMB_NONE);
ut_asserteq(ret, 0);
ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 1, 0x40010000, 0x11000,
0, 0, 0, 0);
- /* allocate 3nd region */
+ /* allocate 2nd region */
ret = lmb_reserve(0x40030000, 0x10000, LMB_NONE);
ut_asserteq(ret, 0);
ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 2, 0x40010000, 0x11000,
0x40030000, 0x10000, 0, 0);
- /* allocate 2nd region , This should coalesced all region into one */
+ /* allocate 3rd region , This should coalesce all regions into one */
ret = lmb_reserve(0x40020000, 0x10000, LMB_NONE);
ut_assert(ret >= 0);
ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 1, 0x40010000, 0x30000,
@@ -499,6 +499,41 @@ static int lib_test_lmb_overlapping_reserve(struct
unit_test_state *uts)
ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 1, 0x40000000, 0x40000,
0, 0, 0, 0);
+ /* try to allocate overlapping region with a different flag, should
fail */
+ ret = lmb_reserve(0x40008000, 0x1000, LMB_NOOVERWRITE);
+ ut_asserteq(ret, -EEXIST);
+
+ /* allocate another region at 0x40050000 with a different flag */
+ ret = lmb_reserve(0x40050000, 0x10000, LMB_NOOVERWRITE);
+ ut_asserteq(ret, 0);
+ ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 2, 0x40000000, 0x40000,
+ 0x40050000, 0x10000, 0, 0);
+
+ /*
+ * try to reserve a region adjacent to region 1 overlapping the 2nd
region,
+ * should fail
+ */
+ ret = lmb_reserve(0x40040000, 0x20000, LMB_NONE);
+ ut_asserteq(ret, -EEXIST);
+
+ /*
+ * try to reserve a region between the two regions, but without an
overlap,
+ * should succeed. this added region coalesces with the region 1
+ */
+ ret = lmb_reserve(0x40040000, 0x10000, LMB_NONE);
+ ut_asserteq(ret, 0);
+ ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 2, 0x40000000, 0x50000,
+ 0x40050000, 0x10000, 0, 0);
+
+ /*
+ * try to reserve a region which overlaps with both the regions,
+ * should fail as the flags do not match
+ */
+ ret = lmb_reserve(0x40020000, 0x80000, LMB_NONE);
+ ut_asserteq(ret, -EEXIST);
+ ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 2, 0x40000000, 0x50000,
+ 0x40050000, 0x10000, 0, 0);
+
lmb_pop(&store);
return 0;
@@ -549,6 +584,77 @@ static int test_alloc_addr(struct unit_test_state *uts,
const phys_addr_t ram)
ret = lmb_free(alloc_addr_a, 0x1000);
ut_asserteq(ret, 0);
+ /*
+ * Add two regions with different flags, region1 and region2 with
+ * a gap between them.
+ * Try adding another region, adjacent to region 1 and overlapping
+ * region 2. Should fail.
+ */
+ a = lmb_alloc_addr(alloc_addr_a, 0x1000, LMB_NONE);
+ ut_asserteq(a, alloc_addr_a);
+
+ b = lmb_alloc_addr(alloc_addr_a + 0x4000, 0x1000, LMB_NOOVERWRITE);
+ ut_asserteq(b, alloc_addr_a + 0x4000);
+ ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 2, a, 0x1000,
+ b, 0x1000, 0, 0);
+
+ c = lmb_alloc_addr(alloc_addr_a + 0x1000, 0x5000, LMB_NONE);
+ ut_asserteq(c, 0);
+ ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 2, a, 0x1000,
+ b, 0x1000, 0, 0);
+
+ ret = lmb_free(a, 0x1000);
+ ut_asserteq(ret, 0);
+ ret = lmb_free(b, 0x1000);
+ ut_asserteq(ret, 0);
+
+ /*
+ * Add two regions with same flags(LMB_NONE), region1 and region2
+ * with a gap between them.
+ * Try adding another region, adjacent to region 1 and overlapping
+ * region 2. Should succeed. All regions should coalesce into a
+ * single region.
+ */
+ a = lmb_alloc_addr(alloc_addr_a, 0x1000, LMB_NONE);
+ ut_asserteq(a, alloc_addr_a);
+
+ b = lmb_alloc_addr(alloc_addr_a + 0x4000, 0x1000, LMB_NONE);
+ ut_asserteq(b, alloc_addr_a + 0x4000);
+ ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 2, a, 0x1000,
+ b, 0x1000, 0, 0);
+
+ c = lmb_alloc_addr(alloc_addr_a + 0x1000, 0x5000, LMB_NONE);
+ ut_asserteq(c, alloc_addr_a + 0x1000);
+ ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 1, a, 0x6000,
+ 0, 0, 0, 0);
+
+ ret = lmb_free(a, 0x6000);
+ ut_asserteq(ret, 0);
+
+ /*
+ * Add two regions with same flags(LMB_NOOVERWRITE), region1 and
+ * region2 with a gap between them.
+ * Try adding another region, adjacent to region 1 and overlapping
+ * region 2. Should fail.
+ */
+ a = lmb_alloc_addr(alloc_addr_a, 0x1000, LMB_NOOVERWRITE);
+ ut_asserteq(a, alloc_addr_a);
+
+ b = lmb_alloc_addr(alloc_addr_a + 0x4000, 0x1000, LMB_NOOVERWRITE);
+ ut_asserteq(b, alloc_addr_a + 0x4000);
+ ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 2, a, 0x1000,
+ b, 0x1000, 0, 0);
+
+ c = lmb_alloc_addr(alloc_addr_a + 0x1000, 0x5000, LMB_NOOVERWRITE);
+ ut_asserteq(c, 0);
+ ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 2, a, 0x1000,
+ b, 0x1000, 0, 0);
+
+ ret = lmb_free(a, 0x1000);
+ ut_asserteq(ret, 0);
+ ret = lmb_free(b, 0x1000);
+ ut_asserteq(ret, 0);
+
/* reserve 3 blocks */
ret = lmb_reserve(alloc_addr_a, 0x10000, LMB_NONE);
ut_asserteq(ret, 0);
@@ -760,7 +866,7 @@ static int lib_test_lmb_flags(struct unit_test_state *uts)
/* reserve again, new flag */
ret = lmb_reserve(0x40010000, 0x10000, LMB_NONE);
- ut_asserteq(ret, -1);
+ ut_asserteq(ret, -EEXIST);
ASSERT_LMB(mem_lst, used_lst, ram, ram_size, 1, 0x40010000, 0x10000,
0, 0, 0, 0);
--
2.34.1
