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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /lib/generic-radix-tree.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'lib/generic-radix-tree.c')
-rw-r--r--lib/generic-radix-tree.c230
1 files changed, 230 insertions, 0 deletions
diff --git a/lib/generic-radix-tree.c b/lib/generic-radix-tree.c
new file mode 100644
index 000000000..79e067b51
--- /dev/null
+++ b/lib/generic-radix-tree.c
@@ -0,0 +1,230 @@
+
+#include <linux/atomic.h>
+#include <linux/export.h>
+#include <linux/generic-radix-tree.h>
+#include <linux/gfp.h>
+#include <linux/kmemleak.h>
+
+/*
+ * Returns pointer to the specified byte @offset within @radix, or NULL if not
+ * allocated
+ */
+void *__genradix_ptr(struct __genradix *radix, size_t offset)
+{
+ return __genradix_ptr_inlined(radix, offset);
+}
+EXPORT_SYMBOL(__genradix_ptr);
+
+/*
+ * Returns pointer to the specified byte @offset within @radix, allocating it if
+ * necessary - newly allocated slots are always zeroed out:
+ */
+void *__genradix_ptr_alloc(struct __genradix *radix, size_t offset,
+ struct genradix_node **preallocated,
+ gfp_t gfp_mask)
+{
+ struct genradix_root *v = READ_ONCE(radix->root);
+ struct genradix_node *n, *new_node = NULL;
+ unsigned level;
+
+ if (preallocated)
+ swap(new_node, *preallocated);
+
+ /* Increase tree depth if necessary: */
+ while (1) {
+ struct genradix_root *r = v, *new_root;
+
+ n = genradix_root_to_node(r);
+ level = genradix_root_to_depth(r);
+
+ if (n && ilog2(offset) < genradix_depth_shift(level))
+ break;
+
+ if (!new_node) {
+ new_node = genradix_alloc_node(gfp_mask);
+ if (!new_node)
+ return NULL;
+ }
+
+ new_node->children[0] = n;
+ new_root = ((struct genradix_root *)
+ ((unsigned long) new_node | (n ? level + 1 : 0)));
+
+ if ((v = cmpxchg_release(&radix->root, r, new_root)) == r) {
+ v = new_root;
+ new_node = NULL;
+ } else {
+ new_node->children[0] = NULL;
+ }
+ }
+
+ while (level--) {
+ struct genradix_node **p =
+ &n->children[offset >> genradix_depth_shift(level)];
+ offset &= genradix_depth_size(level) - 1;
+
+ n = READ_ONCE(*p);
+ if (!n) {
+ if (!new_node) {
+ new_node = genradix_alloc_node(gfp_mask);
+ if (!new_node)
+ return NULL;
+ }
+
+ if (!(n = cmpxchg_release(p, NULL, new_node)))
+ swap(n, new_node);
+ }
+ }
+
+ if (new_node)
+ genradix_free_node(new_node);
+
+ return &n->data[offset];
+}
+EXPORT_SYMBOL(__genradix_ptr_alloc);
+
+void *__genradix_iter_peek(struct genradix_iter *iter,
+ struct __genradix *radix,
+ size_t objs_per_page)
+{
+ struct genradix_root *r;
+ struct genradix_node *n;
+ unsigned level, i;
+
+ if (iter->offset == SIZE_MAX)
+ return NULL;
+
+restart:
+ r = READ_ONCE(radix->root);
+ if (!r)
+ return NULL;
+
+ n = genradix_root_to_node(r);
+ level = genradix_root_to_depth(r);
+
+ if (ilog2(iter->offset) >= genradix_depth_shift(level))
+ return NULL;
+
+ while (level) {
+ level--;
+
+ i = (iter->offset >> genradix_depth_shift(level)) &
+ (GENRADIX_ARY - 1);
+
+ while (!n->children[i]) {
+ size_t objs_per_ptr = genradix_depth_size(level);
+
+ if (iter->offset + objs_per_ptr < iter->offset) {
+ iter->offset = SIZE_MAX;
+ iter->pos = SIZE_MAX;
+ return NULL;
+ }
+
+ i++;
+ iter->offset = round_down(iter->offset + objs_per_ptr,
+ objs_per_ptr);
+ iter->pos = (iter->offset >> GENRADIX_NODE_SHIFT) *
+ objs_per_page;
+ if (i == GENRADIX_ARY)
+ goto restart;
+ }
+
+ n = n->children[i];
+ }
+
+ return &n->data[iter->offset & (GENRADIX_NODE_SIZE - 1)];
+}
+EXPORT_SYMBOL(__genradix_iter_peek);
+
+void *__genradix_iter_peek_prev(struct genradix_iter *iter,
+ struct __genradix *radix,
+ size_t objs_per_page,
+ size_t obj_size_plus_page_remainder)
+{
+ struct genradix_root *r;
+ struct genradix_node *n;
+ unsigned level, i;
+
+ if (iter->offset == SIZE_MAX)
+ return NULL;
+
+restart:
+ r = READ_ONCE(radix->root);
+ if (!r)
+ return NULL;
+
+ n = genradix_root_to_node(r);
+ level = genradix_root_to_depth(r);
+
+ if (ilog2(iter->offset) >= genradix_depth_shift(level)) {
+ iter->offset = genradix_depth_size(level);
+ iter->pos = (iter->offset >> GENRADIX_NODE_SHIFT) * objs_per_page;
+
+ iter->offset -= obj_size_plus_page_remainder;
+ iter->pos--;
+ }
+
+ while (level) {
+ level--;
+
+ i = (iter->offset >> genradix_depth_shift(level)) &
+ (GENRADIX_ARY - 1);
+
+ while (!n->children[i]) {
+ size_t objs_per_ptr = genradix_depth_size(level);
+
+ iter->offset = round_down(iter->offset, objs_per_ptr);
+ iter->pos = (iter->offset >> GENRADIX_NODE_SHIFT) * objs_per_page;
+
+ if (!iter->offset)
+ return NULL;
+
+ iter->offset -= obj_size_plus_page_remainder;
+ iter->pos--;
+
+ if (!i)
+ goto restart;
+ --i;
+ }
+
+ n = n->children[i];
+ }
+
+ return &n->data[iter->offset & (GENRADIX_NODE_SIZE - 1)];
+}
+EXPORT_SYMBOL(__genradix_iter_peek_prev);
+
+static void genradix_free_recurse(struct genradix_node *n, unsigned level)
+{
+ if (level) {
+ unsigned i;
+
+ for (i = 0; i < GENRADIX_ARY; i++)
+ if (n->children[i])
+ genradix_free_recurse(n->children[i], level - 1);
+ }
+
+ genradix_free_node(n);
+}
+
+int __genradix_prealloc(struct __genradix *radix, size_t size,
+ gfp_t gfp_mask)
+{
+ size_t offset;
+
+ for (offset = 0; offset < size; offset += GENRADIX_NODE_SIZE)
+ if (!__genradix_ptr_alloc(radix, offset, NULL, gfp_mask))
+ return -ENOMEM;
+
+ return 0;
+}
+EXPORT_SYMBOL(__genradix_prealloc);
+
+void __genradix_free(struct __genradix *radix)
+{
+ struct genradix_root *r = xchg(&radix->root, NULL);
+
+ genradix_free_recurse(genradix_root_to_node(r),
+ genradix_root_to_depth(r));
+}
+EXPORT_SYMBOL(__genradix_free);