lmb_add_region handles overlapping regions wrong: instead of merging or rejecting to add a new reserved region that overlaps an existing one, it just adds the new region.
Since internally the same function is used for lmb_alloc, change lmb_add_region to reject overlapping regions.
Also, to keep reserved memory correct after 'free', reserved entries created by allocating memory must not set their size to a multiple of alignment but to the original size. This ensures the reserved region is completely removed when the caller calls 'lmb_free', as this one takes the same size as passed to 'lmb_alloc' etc.
Add test to assert this.
Signed-off-by: Simon Goldschmidt simon.k.r.goldschmidt@gmail.com ---
Changes in v6: - fix size of allocated regions that need alignment padding
Changes in v5: - added a test for this bug
Changes in v4: None Changes in v2: None
lib/lmb.c | 11 +++--- test/lib/lmb.c | 94 +++++++++++++++++++++++++++++++++++++++++++++----- 2 files changed, 90 insertions(+), 15 deletions(-)
diff --git a/lib/lmb.c b/lib/lmb.c index 6d3dcf4e09..cd297f8202 100644 --- a/lib/lmb.c +++ b/lib/lmb.c @@ -131,6 +131,9 @@ static long lmb_add_region(struct lmb_region *rgn, phys_addr_t base, phys_size_t rgn->region[i].size += size; coalesced++; break; + } else if (lmb_addrs_overlap(base, size, rgnbase, rgnsize)) { + /* regions overlap */ + return -1; } }
@@ -269,11 +272,6 @@ static phys_addr_t lmb_align_down(phys_addr_t addr, phys_size_t size) return addr & ~(size - 1); }
-static phys_addr_t lmb_align_up(phys_addr_t addr, ulong size) -{ - return (addr + (size - 1)) & ~(size - 1); -} - phys_addr_t __lmb_alloc_base(struct lmb *lmb, phys_size_t size, ulong align, phys_addr_t max_addr) { long i, j; @@ -302,8 +300,7 @@ phys_addr_t __lmb_alloc_base(struct lmb *lmb, phys_size_t size, ulong align, phy if (j < 0) { /* This area isn't reserved, take it */ if (lmb_add_region(&lmb->reserved, base, - lmb_align_up(size, - align)) < 0) + size) < 0) return 0; return base; } diff --git a/test/lib/lmb.c b/test/lib/lmb.c index fb7ca45ef1..ffa3d53bf1 100644 --- a/test/lib/lmb.c +++ b/test/lib/lmb.c @@ -227,13 +227,16 @@ static int lib_test_lmb_big(struct unit_test_state *uts) DM_TEST(lib_test_lmb_big, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
/* Simulate 512 MiB RAM, allocate a block without previous reservation */ -static int test_noreserved(struct unit_test_state *uts, const phys_addr_t ram) +static int test_noreserved(struct unit_test_state *uts, const phys_addr_t ram, + const phys_addr_t alloc_size, const ulong align) { const phys_size_t ram_size = 0x20000000; const phys_addr_t ram_end = ram + ram_size; struct lmb lmb; long ret; phys_addr_t a, b; + const phys_addr_t alloc_size_aligned = (alloc_size + align - 1) & + ~(align - 1);
/* check for overflow */ ut_assert(ram_end == 0 || ram_end > ram); @@ -242,20 +245,42 @@ static int test_noreserved(struct unit_test_state *uts, const phys_addr_t ram)
ret = lmb_add(&lmb, ram, ram_size); ut_asserteq(ret, 0); + ASSERT_LMB(&lmb, ram, ram_size, 0, 0, 0, 0, 0, 0, 0);
/* allocate a block */ - a = lmb_alloc(&lmb, 4, 1); + a = lmb_alloc(&lmb, alloc_size, align); ut_assert(a != 0); - /* and free it */ - ret = lmb_free(&lmb, a, 4); + ASSERT_LMB(&lmb, ram, ram_size, 1, ram + ram_size - alloc_size_aligned, + alloc_size, 0, 0, 0, 0); + /* allocate another block */ + b = lmb_alloc(&lmb, alloc_size, align); + ut_assert(b != 0); + if (alloc_size == alloc_size_aligned) + ASSERT_LMB(&lmb, ram, ram_size, 1, ram + ram_size - + (alloc_size_aligned * 2), alloc_size * 2, 0, 0, 0, + 0); + else + ASSERT_LMB(&lmb, ram, ram_size, 2, ram + ram_size - + (alloc_size_aligned * 2), alloc_size, ram + ram_size + - alloc_size_aligned, alloc_size, 0, 0); + /* and free them */ + ret = lmb_free(&lmb, b, alloc_size); + ut_asserteq(ret, 0); + ASSERT_LMB(&lmb, ram, ram_size, 1, ram + ram_size - alloc_size_aligned, + alloc_size, 0, 0, 0, 0); + ret = lmb_free(&lmb, a, alloc_size); ut_asserteq(ret, 0); + ASSERT_LMB(&lmb, ram, ram_size, 0, 0, 0, 0, 0, 0, 0);
/* allocate a block with base*/ - b = lmb_alloc_base(&lmb, 4, 1, ram_end); + b = lmb_alloc_base(&lmb, alloc_size, align, ram_end); ut_assert(a == b); + ASSERT_LMB(&lmb, ram, ram_size, 1, ram + ram_size - alloc_size_aligned, + alloc_size, 0, 0, 0, 0); /* and free it */ - ret = lmb_free(&lmb, b, 4); + ret = lmb_free(&lmb, b, alloc_size); ut_asserteq(ret, 0); + ASSERT_LMB(&lmb, ram, ram_size, 0, 0, 0, 0, 0, 0, 0);
return 0; } @@ -265,16 +290,30 @@ static int lib_test_lmb_noreserved(struct unit_test_state *uts) int ret;
/* simulate 512 MiB RAM beginning at 1GiB */ - ret = test_noreserved(uts, 0x40000000); + ret = test_noreserved(uts, 0x40000000, 4, 1); if (ret) return ret;
/* simulate 512 MiB RAM beginning at 1.5GiB */ - return test_noreserved(uts, 0xE0000000); + return test_noreserved(uts, 0xE0000000, 4, 1); }
DM_TEST(lib_test_lmb_noreserved, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+static int lib_test_lmb_unaligned_size(struct unit_test_state *uts) +{ + int ret; + + /* simulate 512 MiB RAM beginning at 1GiB */ + ret = test_noreserved(uts, 0x40000000, 5, 8); + if (ret) + return ret; + + /* simulate 512 MiB RAM beginning at 1.5GiB */ + return test_noreserved(uts, 0xE0000000, 5, 8); +} + +DM_TEST(lib_test_lmb_unaligned_size, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT); /* * Simulate a RAM that starts at 0 and allocate down to address 0, which must * fail as '0' means failure for the lmb_alloc functions. @@ -318,3 +357,42 @@ static int lib_test_lmb_at_0(struct unit_test_state *uts) }
DM_TEST(lib_test_lmb_at_0, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT); + +/* Check that calling lmb_reserve with overlapping regions fails. */ +static int lib_test_lmb_overlapping_reserve(struct unit_test_state *uts) +{ + const phys_addr_t ram = 0x40000000; + const phys_size_t ram_size = 0x20000000; + struct lmb lmb; + long ret; + + lmb_init(&lmb); + + ret = lmb_add(&lmb, ram, ram_size); + ut_asserteq(ret, 0); + + ret = lmb_reserve(&lmb, 0x40010000, 0x10000); + ut_asserteq(ret, 0); + ASSERT_LMB(&lmb, ram, ram_size, 1, 0x40010000, 0x10000, + 0, 0, 0, 0); + /* allocate overlapping region should fail */ + ret = lmb_reserve(&lmb, 0x40011000, 0x10000); + ut_asserteq(ret, -1); + ASSERT_LMB(&lmb, ram, ram_size, 1, 0x40010000, 0x10000, + 0, 0, 0, 0); + /* allocate 3nd region */ + ret = lmb_reserve(&lmb, 0x40030000, 0x10000); + ut_asserteq(ret, 0); + ASSERT_LMB(&lmb, ram, ram_size, 2, 0x40010000, 0x10000, + 0x40030000, 0x10000, 0, 0); + /* allocate 2nd region */ + ret = lmb_reserve(&lmb, 0x40020000, 0x10000); + ut_assert(ret >= 0); + ASSERT_LMB(&lmb, ram, ram_size, 1, 0x40010000, 0x30000, + 0, 0, 0, 0); + + return 0; +} + +DM_TEST(lib_test_lmb_overlapping_reserve, + DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);