Allow for resizing of LMB regions if the region attributes match. The
current code returns a failure status on detecting an overlapping
address. This worked up until now since the LMB calls were not
persistent and global -- the LMB memory map was specific and private
to a given caller of the LMB API's.
With the change in the LMB code to make the LMB reservations
persistent, there needs to be a check on whether the memory region can
be resized, and then do it if so. To distinguish between memory that
cannot be resized, add a new flag, LMB_NOOVERWRITE. Reserving a region
of memory with this attribute would indicate that the region cannot be
resized.
Signed-off-by: Sughosh Ganu <sughosh.g...@linaro.org>
---
include/lmb.h | 1 +
lib/lmb.c | 120 ++++++++++++++++++++++++++++++++++++++++++++------
2 files changed, 107 insertions(+), 14 deletions(-)
diff --git a/include/lmb.h b/include/lmb.h
index 03bce2a50c..1d4cd255d2 100644
--- a/include/lmb.h
+++ b/include/lmb.h
@@ -20,6 +20,7 @@
enum lmb_flags {
LMB_NONE = 0x0,
LMB_NOMAP = 0x4,
+ LMB_NOOVERWRITE = 0x8,
};
/**
diff --git a/lib/lmb.c b/lib/lmb.c
index de5a2cf23b..0a4f3d5bcd 100644
--- a/lib/lmb.c
+++ b/lib/lmb.c
@@ -260,12 +260,88 @@ void lmb_add_memory(struct bd_info *bd)
}
}
+static bool lmb_region_flags_match(struct lmb_region *rgn, unsigned long r1,
+ enum lmb_flags flags)
+{
+ return rgn->region[r1].flags == flags;
+}
+
+static long lmb_merge_overlap_regions(struct lmb_region *rgn, unsigned long i,
+ phys_addr_t base, phys_size_t size,
+ enum lmb_flags flags)
+{
+ phys_size_t rgnsize;
+ unsigned long rgn_cnt, idx;
+ phys_addr_t rgnbase, rgnend;
+ phys_addr_t mergebase, mergeend;
+
+ rgn_cnt = 0;
+ idx = i;
+ /*
+ * First thing to do is to identify how many regions does
+ * the requested region overlap.
+ * If the flags match, combine all these overlapping
+ * regions into a single region, and remove the merged
+ * regions.
+ */
+ while (idx < rgn->cnt - 1) {
+ rgnbase = rgn->region[idx].base;
+ rgnsize = rgn->region[idx].size;
+
+ if (lmb_addrs_overlap(base, size, rgnbase,
+ rgnsize)) {
+ if (!lmb_region_flags_match(rgn, idx, flags))
+ return -1;
+ rgn_cnt++;
+ idx++;
+ }
+ }
+
+ /* The merged region's base and size */
+ rgnbase = rgn->region[i].base;
+ mergebase = min(base, rgnbase);
+ rgnend = rgn->region[idx].base + rgn->region[idx].size;
+ mergeend = max(rgnend, (base + size));
+
+ rgn->region[i].base = mergebase;
+ rgn->region[i].size = mergeend - mergebase;
+
+ /* Now remove the merged regions */
+ while (--rgn_cnt)
+ lmb_remove_region(rgn, i + 1);
+
+ return 0;
+}
+
+static long lmb_resize_regions(struct lmb_region *rgn, unsigned long i,
+ phys_addr_t base, phys_size_t size,
+ enum lmb_flags flags)
+{
+ long ret = 0;
+ phys_addr_t rgnend;
+
+ if (i == rgn->cnt - 1 ||
+ base + size < rgn->region[i + 1].base) {
+ if (!lmb_region_flags_match(rgn, i, flags))
+ return -1;
+
+ rgnend = rgn->region[i].base + rgn->region[i].size;
+ rgn->region[i].base = min(base, rgn->region[i].base);
+ rgnend = max(base + size, rgnend);
+ rgn->region[i].size = rgnend - rgn->region[i].base;
+ } else {
+ ret = lmb_merge_overlap_regions(rgn, i, base, size, flags);
+ }
+
+ return ret;
+}
+
/* This routine called with relocation disabled. */
static long lmb_add_region_flags(struct lmb_region *rgn, phys_addr_t base,
phys_size_t size, enum lmb_flags flags)
{
unsigned long coalesced = 0;
- long adjacent, i;
+ long ret, i;
if (rgn->cnt == 0) {
rgn->region[0].base = base;
@@ -290,23 +366,32 @@ static long lmb_add_region_flags(struct lmb_region *rgn,
phys_addr_t base,
return -1; /* regions with new flags */
}
- adjacent = lmb_addrs_adjacent(base, size, rgnbase, rgnsize);
- if (adjacent > 0) {
+ ret = lmb_addrs_adjacent(base, size, rgnbase, rgnsize);
+ if (ret > 0) {
if (flags != rgnflags)
break;
rgn->region[i].base -= size;
rgn->region[i].size += size;
coalesced++;
break;
- } else if (adjacent < 0) {
+ } else if (ret < 0) {
if (flags != rgnflags)
break;
rgn->region[i].size += size;
coalesced++;
break;
} else if (lmb_addrs_overlap(base, size, rgnbase, rgnsize)) {
- /* regions overlap */
- return -1;
+ if (flags == LMB_NONE) {
+ ret = lmb_resize_regions(rgn, i, base, size,
+ flags);
+ if (ret < 0)
+ return -1;
+
+ coalesced++;
+ break;
+ } else {
+ return -1;
+ }
}
}
@@ -448,7 +533,7 @@ static phys_addr_t lmb_align_down(phys_addr_t addr,
phys_size_t size)
}
static phys_addr_t __lmb_alloc_base(phys_size_t size, ulong align,
- phys_addr_t max_addr)
+ phys_addr_t max_addr, enum lmb_flags flags)
{
long i, rgn;
phys_addr_t base = 0;
@@ -498,7 +583,7 @@ phys_addr_t lmb_alloc_base(phys_size_t size, ulong align,
phys_addr_t max_addr)
{
phys_addr_t alloc;
- alloc = __lmb_alloc_base(size, align, max_addr);
+ alloc = __lmb_alloc_base(size, align, max_addr, LMB_NONE);
if (alloc == 0)
printf("ERROR: Failed to allocate 0x%lx bytes below 0x%lx.\n",
@@ -507,11 +592,8 @@ phys_addr_t lmb_alloc_base(phys_size_t size, ulong align,
phys_addr_t max_addr)
return alloc;
}
-/*
- * Try to allocate a specific address range: must be in defined memory but not
- * reserved
- */
-phys_addr_t lmb_alloc_addr(phys_addr_t base, phys_size_t size)
+static phys_addr_t __lmb_alloc_addr(phys_addr_t base, phys_size_t size,
+ enum lmb_flags flags)
{
long rgn;
@@ -526,13 +608,23 @@ phys_addr_t lmb_alloc_addr(phys_addr_t base, phys_size_t
size)
lmb.memory.region[rgn].size,
base + size - 1, 1)) {
/* ok, reserve the memory */
- if (lmb_reserve(base, size) >= 0)
+ if (lmb_reserve_flags(base, size, flags) >= 0)
return base;
}
}
+
return 0;
}
+/*
+ * Try to allocate a specific address range: must be in defined memory but not
+ * reserved
+ */
+phys_addr_t lmb_alloc_addr(phys_addr_t base, phys_size_t size)
+{
+ return __lmb_alloc_addr(base, size, LMB_NONE);
+}
+
/* Return number of bytes from a given address that are free */
phys_size_t lmb_get_free_size(phys_addr_t addr)
{
--
2.34.1
