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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /lib/genalloc.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'lib/genalloc.c')
-rw-r--r--lib/genalloc.c909
1 files changed, 909 insertions, 0 deletions
diff --git a/lib/genalloc.c b/lib/genalloc.c
new file mode 100644
index 000000000..00fc50d0a
--- /dev/null
+++ b/lib/genalloc.c
@@ -0,0 +1,909 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Basic general purpose allocator for managing special purpose
+ * memory, for example, memory that is not managed by the regular
+ * kmalloc/kfree interface. Uses for this includes on-device special
+ * memory, uncached memory etc.
+ *
+ * It is safe to use the allocator in NMI handlers and other special
+ * unblockable contexts that could otherwise deadlock on locks. This
+ * is implemented by using atomic operations and retries on any
+ * conflicts. The disadvantage is that there may be livelocks in
+ * extreme cases. For better scalability, one allocator can be used
+ * for each CPU.
+ *
+ * The lockless operation only works if there is enough memory
+ * available. If new memory is added to the pool a lock has to be
+ * still taken. So any user relying on locklessness has to ensure
+ * that sufficient memory is preallocated.
+ *
+ * The basic atomic operation of this allocator is cmpxchg on long.
+ * On architectures that don't have NMI-safe cmpxchg implementation,
+ * the allocator can NOT be used in NMI handler. So code uses the
+ * allocator in NMI handler should depend on
+ * CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG.
+ *
+ * Copyright 2005 (C) Jes Sorensen <jes@trained-monkey.org>
+ */
+
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <linux/bitmap.h>
+#include <linux/rculist.h>
+#include <linux/interrupt.h>
+#include <linux/genalloc.h>
+#include <linux/of_device.h>
+#include <linux/vmalloc.h>
+
+static inline size_t chunk_size(const struct gen_pool_chunk *chunk)
+{
+ return chunk->end_addr - chunk->start_addr + 1;
+}
+
+static int set_bits_ll(unsigned long *addr, unsigned long mask_to_set)
+{
+ unsigned long val, nval;
+
+ nval = *addr;
+ do {
+ val = nval;
+ if (val & mask_to_set)
+ return -EBUSY;
+ cpu_relax();
+ } while ((nval = cmpxchg(addr, val, val | mask_to_set)) != val);
+
+ return 0;
+}
+
+static int clear_bits_ll(unsigned long *addr, unsigned long mask_to_clear)
+{
+ unsigned long val, nval;
+
+ nval = *addr;
+ do {
+ val = nval;
+ if ((val & mask_to_clear) != mask_to_clear)
+ return -EBUSY;
+ cpu_relax();
+ } while ((nval = cmpxchg(addr, val, val & ~mask_to_clear)) != val);
+
+ return 0;
+}
+
+/*
+ * bitmap_set_ll - set the specified number of bits at the specified position
+ * @map: pointer to a bitmap
+ * @start: a bit position in @map
+ * @nr: number of bits to set
+ *
+ * Set @nr bits start from @start in @map lock-lessly. Several users
+ * can set/clear the same bitmap simultaneously without lock. If two
+ * users set the same bit, one user will return remain bits, otherwise
+ * return 0.
+ */
+static unsigned long
+bitmap_set_ll(unsigned long *map, unsigned long start, unsigned long nr)
+{
+ unsigned long *p = map + BIT_WORD(start);
+ const unsigned long size = start + nr;
+ int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
+ unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
+
+ while (nr >= bits_to_set) {
+ if (set_bits_ll(p, mask_to_set))
+ return nr;
+ nr -= bits_to_set;
+ bits_to_set = BITS_PER_LONG;
+ mask_to_set = ~0UL;
+ p++;
+ }
+ if (nr) {
+ mask_to_set &= BITMAP_LAST_WORD_MASK(size);
+ if (set_bits_ll(p, mask_to_set))
+ return nr;
+ }
+
+ return 0;
+}
+
+/*
+ * bitmap_clear_ll - clear the specified number of bits at the specified position
+ * @map: pointer to a bitmap
+ * @start: a bit position in @map
+ * @nr: number of bits to set
+ *
+ * Clear @nr bits start from @start in @map lock-lessly. Several users
+ * can set/clear the same bitmap simultaneously without lock. If two
+ * users clear the same bit, one user will return remain bits,
+ * otherwise return 0.
+ */
+static unsigned long
+bitmap_clear_ll(unsigned long *map, unsigned long start, unsigned long nr)
+{
+ unsigned long *p = map + BIT_WORD(start);
+ const unsigned long size = start + nr;
+ int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
+ unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
+
+ while (nr >= bits_to_clear) {
+ if (clear_bits_ll(p, mask_to_clear))
+ return nr;
+ nr -= bits_to_clear;
+ bits_to_clear = BITS_PER_LONG;
+ mask_to_clear = ~0UL;
+ p++;
+ }
+ if (nr) {
+ mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
+ if (clear_bits_ll(p, mask_to_clear))
+ return nr;
+ }
+
+ return 0;
+}
+
+/**
+ * gen_pool_create - create a new special memory pool
+ * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents
+ * @nid: node id of the node the pool structure should be allocated on, or -1
+ *
+ * Create a new special memory pool that can be used to manage special purpose
+ * memory not managed by the regular kmalloc/kfree interface.
+ */
+struct gen_pool *gen_pool_create(int min_alloc_order, int nid)
+{
+ struct gen_pool *pool;
+
+ pool = kmalloc_node(sizeof(struct gen_pool), GFP_KERNEL, nid);
+ if (pool != NULL) {
+ spin_lock_init(&pool->lock);
+ INIT_LIST_HEAD(&pool->chunks);
+ pool->min_alloc_order = min_alloc_order;
+ pool->algo = gen_pool_first_fit;
+ pool->data = NULL;
+ pool->name = NULL;
+ }
+ return pool;
+}
+EXPORT_SYMBOL(gen_pool_create);
+
+/**
+ * gen_pool_add_owner- add a new chunk of special memory to the pool
+ * @pool: pool to add new memory chunk to
+ * @virt: virtual starting address of memory chunk to add to pool
+ * @phys: physical starting address of memory chunk to add to pool
+ * @size: size in bytes of the memory chunk to add to pool
+ * @nid: node id of the node the chunk structure and bitmap should be
+ * allocated on, or -1
+ * @owner: private data the publisher would like to recall at alloc time
+ *
+ * Add a new chunk of special memory to the specified pool.
+ *
+ * Returns 0 on success or a -ve errno on failure.
+ */
+int gen_pool_add_owner(struct gen_pool *pool, unsigned long virt, phys_addr_t phys,
+ size_t size, int nid, void *owner)
+{
+ struct gen_pool_chunk *chunk;
+ unsigned long nbits = size >> pool->min_alloc_order;
+ unsigned long nbytes = sizeof(struct gen_pool_chunk) +
+ BITS_TO_LONGS(nbits) * sizeof(long);
+
+ chunk = vzalloc_node(nbytes, nid);
+ if (unlikely(chunk == NULL))
+ return -ENOMEM;
+
+ chunk->phys_addr = phys;
+ chunk->start_addr = virt;
+ chunk->end_addr = virt + size - 1;
+ chunk->owner = owner;
+ atomic_long_set(&chunk->avail, size);
+
+ spin_lock(&pool->lock);
+ list_add_rcu(&chunk->next_chunk, &pool->chunks);
+ spin_unlock(&pool->lock);
+
+ return 0;
+}
+EXPORT_SYMBOL(gen_pool_add_owner);
+
+/**
+ * gen_pool_virt_to_phys - return the physical address of memory
+ * @pool: pool to allocate from
+ * @addr: starting address of memory
+ *
+ * Returns the physical address on success, or -1 on error.
+ */
+phys_addr_t gen_pool_virt_to_phys(struct gen_pool *pool, unsigned long addr)
+{
+ struct gen_pool_chunk *chunk;
+ phys_addr_t paddr = -1;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) {
+ if (addr >= chunk->start_addr && addr <= chunk->end_addr) {
+ paddr = chunk->phys_addr + (addr - chunk->start_addr);
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ return paddr;
+}
+EXPORT_SYMBOL(gen_pool_virt_to_phys);
+
+/**
+ * gen_pool_destroy - destroy a special memory pool
+ * @pool: pool to destroy
+ *
+ * Destroy the specified special memory pool. Verifies that there are no
+ * outstanding allocations.
+ */
+void gen_pool_destroy(struct gen_pool *pool)
+{
+ struct list_head *_chunk, *_next_chunk;
+ struct gen_pool_chunk *chunk;
+ int order = pool->min_alloc_order;
+ unsigned long bit, end_bit;
+
+ list_for_each_safe(_chunk, _next_chunk, &pool->chunks) {
+ chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk);
+ list_del(&chunk->next_chunk);
+
+ end_bit = chunk_size(chunk) >> order;
+ bit = find_first_bit(chunk->bits, end_bit);
+ BUG_ON(bit < end_bit);
+
+ vfree(chunk);
+ }
+ kfree_const(pool->name);
+ kfree(pool);
+}
+EXPORT_SYMBOL(gen_pool_destroy);
+
+/**
+ * gen_pool_alloc_algo_owner - allocate special memory from the pool
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @algo: algorithm passed from caller
+ * @data: data passed to algorithm
+ * @owner: optionally retrieve the chunk owner
+ *
+ * Allocate the requested number of bytes from the specified pool.
+ * Uses the pool allocation function (with first-fit algorithm by default).
+ * Can not be used in NMI handler on architectures without
+ * NMI-safe cmpxchg implementation.
+ */
+unsigned long gen_pool_alloc_algo_owner(struct gen_pool *pool, size_t size,
+ genpool_algo_t algo, void *data, void **owner)
+{
+ struct gen_pool_chunk *chunk;
+ unsigned long addr = 0;
+ int order = pool->min_alloc_order;
+ unsigned long nbits, start_bit, end_bit, remain;
+
+#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
+ BUG_ON(in_nmi());
+#endif
+
+ if (owner)
+ *owner = NULL;
+
+ if (size == 0)
+ return 0;
+
+ nbits = (size + (1UL << order) - 1) >> order;
+ rcu_read_lock();
+ list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) {
+ if (size > atomic_long_read(&chunk->avail))
+ continue;
+
+ start_bit = 0;
+ end_bit = chunk_size(chunk) >> order;
+retry:
+ start_bit = algo(chunk->bits, end_bit, start_bit,
+ nbits, data, pool, chunk->start_addr);
+ if (start_bit >= end_bit)
+ continue;
+ remain = bitmap_set_ll(chunk->bits, start_bit, nbits);
+ if (remain) {
+ remain = bitmap_clear_ll(chunk->bits, start_bit,
+ nbits - remain);
+ BUG_ON(remain);
+ goto retry;
+ }
+
+ addr = chunk->start_addr + ((unsigned long)start_bit << order);
+ size = nbits << order;
+ atomic_long_sub(size, &chunk->avail);
+ if (owner)
+ *owner = chunk->owner;
+ break;
+ }
+ rcu_read_unlock();
+ return addr;
+}
+EXPORT_SYMBOL(gen_pool_alloc_algo_owner);
+
+/**
+ * gen_pool_dma_alloc - allocate special memory from the pool for DMA usage
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: dma-view physical address return value. Use %NULL if unneeded.
+ *
+ * Allocate the requested number of bytes from the specified pool.
+ * Uses the pool allocation function (with first-fit algorithm by default).
+ * Can not be used in NMI handler on architectures without
+ * NMI-safe cmpxchg implementation.
+ *
+ * Return: virtual address of the allocated memory, or %NULL on failure
+ */
+void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
+{
+ return gen_pool_dma_alloc_algo(pool, size, dma, pool->algo, pool->data);
+}
+EXPORT_SYMBOL(gen_pool_dma_alloc);
+
+/**
+ * gen_pool_dma_alloc_algo - allocate special memory from the pool for DMA
+ * usage with the given pool algorithm
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: DMA-view physical address return value. Use %NULL if unneeded.
+ * @algo: algorithm passed from caller
+ * @data: data passed to algorithm
+ *
+ * Allocate the requested number of bytes from the specified pool. Uses the
+ * given pool allocation function. Can not be used in NMI handler on
+ * architectures without NMI-safe cmpxchg implementation.
+ *
+ * Return: virtual address of the allocated memory, or %NULL on failure
+ */
+void *gen_pool_dma_alloc_algo(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, genpool_algo_t algo, void *data)
+{
+ unsigned long vaddr;
+
+ if (!pool)
+ return NULL;
+
+ vaddr = gen_pool_alloc_algo(pool, size, algo, data);
+ if (!vaddr)
+ return NULL;
+
+ if (dma)
+ *dma = gen_pool_virt_to_phys(pool, vaddr);
+
+ return (void *)vaddr;
+}
+EXPORT_SYMBOL(gen_pool_dma_alloc_algo);
+
+/**
+ * gen_pool_dma_alloc_align - allocate special memory from the pool for DMA
+ * usage with the given alignment
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: DMA-view physical address return value. Use %NULL if unneeded.
+ * @align: alignment in bytes for starting address
+ *
+ * Allocate the requested number bytes from the specified pool, with the given
+ * alignment restriction. Can not be used in NMI handler on architectures
+ * without NMI-safe cmpxchg implementation.
+ *
+ * Return: virtual address of the allocated memory, or %NULL on failure
+ */
+void *gen_pool_dma_alloc_align(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, int align)
+{
+ struct genpool_data_align data = { .align = align };
+
+ return gen_pool_dma_alloc_algo(pool, size, dma,
+ gen_pool_first_fit_align, &data);
+}
+EXPORT_SYMBOL(gen_pool_dma_alloc_align);
+
+/**
+ * gen_pool_dma_zalloc - allocate special zeroed memory from the pool for
+ * DMA usage
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: dma-view physical address return value. Use %NULL if unneeded.
+ *
+ * Allocate the requested number of zeroed bytes from the specified pool.
+ * Uses the pool allocation function (with first-fit algorithm by default).
+ * Can not be used in NMI handler on architectures without
+ * NMI-safe cmpxchg implementation.
+ *
+ * Return: virtual address of the allocated zeroed memory, or %NULL on failure
+ */
+void *gen_pool_dma_zalloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
+{
+ return gen_pool_dma_zalloc_algo(pool, size, dma, pool->algo, pool->data);
+}
+EXPORT_SYMBOL(gen_pool_dma_zalloc);
+
+/**
+ * gen_pool_dma_zalloc_algo - allocate special zeroed memory from the pool for
+ * DMA usage with the given pool algorithm
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: DMA-view physical address return value. Use %NULL if unneeded.
+ * @algo: algorithm passed from caller
+ * @data: data passed to algorithm
+ *
+ * Allocate the requested number of zeroed bytes from the specified pool. Uses
+ * the given pool allocation function. Can not be used in NMI handler on
+ * architectures without NMI-safe cmpxchg implementation.
+ *
+ * Return: virtual address of the allocated zeroed memory, or %NULL on failure
+ */
+void *gen_pool_dma_zalloc_algo(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, genpool_algo_t algo, void *data)
+{
+ void *vaddr = gen_pool_dma_alloc_algo(pool, size, dma, algo, data);
+
+ if (vaddr)
+ memset(vaddr, 0, size);
+
+ return vaddr;
+}
+EXPORT_SYMBOL(gen_pool_dma_zalloc_algo);
+
+/**
+ * gen_pool_dma_zalloc_align - allocate special zeroed memory from the pool for
+ * DMA usage with the given alignment
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: DMA-view physical address return value. Use %NULL if unneeded.
+ * @align: alignment in bytes for starting address
+ *
+ * Allocate the requested number of zeroed bytes from the specified pool,
+ * with the given alignment restriction. Can not be used in NMI handler on
+ * architectures without NMI-safe cmpxchg implementation.
+ *
+ * Return: virtual address of the allocated zeroed memory, or %NULL on failure
+ */
+void *gen_pool_dma_zalloc_align(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, int align)
+{
+ struct genpool_data_align data = { .align = align };
+
+ return gen_pool_dma_zalloc_algo(pool, size, dma,
+ gen_pool_first_fit_align, &data);
+}
+EXPORT_SYMBOL(gen_pool_dma_zalloc_align);
+
+/**
+ * gen_pool_free_owner - free allocated special memory back to the pool
+ * @pool: pool to free to
+ * @addr: starting address of memory to free back to pool
+ * @size: size in bytes of memory to free
+ * @owner: private data stashed at gen_pool_add() time
+ *
+ * Free previously allocated special memory back to the specified
+ * pool. Can not be used in NMI handler on architectures without
+ * NMI-safe cmpxchg implementation.
+ */
+void gen_pool_free_owner(struct gen_pool *pool, unsigned long addr, size_t size,
+ void **owner)
+{
+ struct gen_pool_chunk *chunk;
+ int order = pool->min_alloc_order;
+ unsigned long start_bit, nbits, remain;
+
+#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
+ BUG_ON(in_nmi());
+#endif
+
+ if (owner)
+ *owner = NULL;
+
+ nbits = (size + (1UL << order) - 1) >> order;
+ rcu_read_lock();
+ list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) {
+ if (addr >= chunk->start_addr && addr <= chunk->end_addr) {
+ BUG_ON(addr + size - 1 > chunk->end_addr);
+ start_bit = (addr - chunk->start_addr) >> order;
+ remain = bitmap_clear_ll(chunk->bits, start_bit, nbits);
+ BUG_ON(remain);
+ size = nbits << order;
+ atomic_long_add(size, &chunk->avail);
+ if (owner)
+ *owner = chunk->owner;
+ rcu_read_unlock();
+ return;
+ }
+ }
+ rcu_read_unlock();
+ BUG();
+}
+EXPORT_SYMBOL(gen_pool_free_owner);
+
+/**
+ * gen_pool_for_each_chunk - call func for every chunk of generic memory pool
+ * @pool: the generic memory pool
+ * @func: func to call
+ * @data: additional data used by @func
+ *
+ * Call @func for every chunk of generic memory pool. The @func is
+ * called with rcu_read_lock held.
+ */
+void gen_pool_for_each_chunk(struct gen_pool *pool,
+ void (*func)(struct gen_pool *pool, struct gen_pool_chunk *chunk, void *data),
+ void *data)
+{
+ struct gen_pool_chunk *chunk;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk)
+ func(pool, chunk, data);
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(gen_pool_for_each_chunk);
+
+/**
+ * gen_pool_has_addr - checks if an address falls within the range of a pool
+ * @pool: the generic memory pool
+ * @start: start address
+ * @size: size of the region
+ *
+ * Check if the range of addresses falls within the specified pool. Returns
+ * true if the entire range is contained in the pool and false otherwise.
+ */
+bool gen_pool_has_addr(struct gen_pool *pool, unsigned long start,
+ size_t size)
+{
+ bool found = false;
+ unsigned long end = start + size - 1;
+ struct gen_pool_chunk *chunk;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk) {
+ if (start >= chunk->start_addr && start <= chunk->end_addr) {
+ if (end <= chunk->end_addr) {
+ found = true;
+ break;
+ }
+ }
+ }
+ rcu_read_unlock();
+ return found;
+}
+EXPORT_SYMBOL(gen_pool_has_addr);
+
+/**
+ * gen_pool_avail - get available free space of the pool
+ * @pool: pool to get available free space
+ *
+ * Return available free space of the specified pool.
+ */
+size_t gen_pool_avail(struct gen_pool *pool)
+{
+ struct gen_pool_chunk *chunk;
+ size_t avail = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk)
+ avail += atomic_long_read(&chunk->avail);
+ rcu_read_unlock();
+ return avail;
+}
+EXPORT_SYMBOL_GPL(gen_pool_avail);
+
+/**
+ * gen_pool_size - get size in bytes of memory managed by the pool
+ * @pool: pool to get size
+ *
+ * Return size in bytes of memory managed by the pool.
+ */
+size_t gen_pool_size(struct gen_pool *pool)
+{
+ struct gen_pool_chunk *chunk;
+ size_t size = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk)
+ size += chunk_size(chunk);
+ rcu_read_unlock();
+ return size;
+}
+EXPORT_SYMBOL_GPL(gen_pool_size);
+
+/**
+ * gen_pool_set_algo - set the allocation algorithm
+ * @pool: pool to change allocation algorithm
+ * @algo: custom algorithm function
+ * @data: additional data used by @algo
+ *
+ * Call @algo for each memory allocation in the pool.
+ * If @algo is NULL use gen_pool_first_fit as default
+ * memory allocation function.
+ */
+void gen_pool_set_algo(struct gen_pool *pool, genpool_algo_t algo, void *data)
+{
+ rcu_read_lock();
+
+ pool->algo = algo;
+ if (!pool->algo)
+ pool->algo = gen_pool_first_fit;
+
+ pool->data = data;
+
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(gen_pool_set_algo);
+
+/**
+ * gen_pool_first_fit - find the first available region
+ * of memory matching the size requirement (no alignment constraint)
+ * @map: The address to base the search on
+ * @size: The bitmap size in bits
+ * @start: The bitnumber to start searching at
+ * @nr: The number of zeroed bits we're looking for
+ * @data: additional data - unused
+ * @pool: pool to find the fit region memory from
+ * @start_addr: not used in this function
+ */
+unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size,
+ unsigned long start, unsigned int nr, void *data,
+ struct gen_pool *pool, unsigned long start_addr)
+{
+ return bitmap_find_next_zero_area(map, size, start, nr, 0);
+}
+EXPORT_SYMBOL(gen_pool_first_fit);
+
+/**
+ * gen_pool_first_fit_align - find the first available region
+ * of memory matching the size requirement (alignment constraint)
+ * @map: The address to base the search on
+ * @size: The bitmap size in bits
+ * @start: The bitnumber to start searching at
+ * @nr: The number of zeroed bits we're looking for
+ * @data: data for alignment
+ * @pool: pool to get order from
+ * @start_addr: start addr of alloction chunk
+ */
+unsigned long gen_pool_first_fit_align(unsigned long *map, unsigned long size,
+ unsigned long start, unsigned int nr, void *data,
+ struct gen_pool *pool, unsigned long start_addr)
+{
+ struct genpool_data_align *alignment;
+ unsigned long align_mask, align_off;
+ int order;
+
+ alignment = data;
+ order = pool->min_alloc_order;
+ align_mask = ((alignment->align + (1UL << order) - 1) >> order) - 1;
+ align_off = (start_addr & (alignment->align - 1)) >> order;
+
+ return bitmap_find_next_zero_area_off(map, size, start, nr,
+ align_mask, align_off);
+}
+EXPORT_SYMBOL(gen_pool_first_fit_align);
+
+/**
+ * gen_pool_fixed_alloc - reserve a specific region
+ * @map: The address to base the search on
+ * @size: The bitmap size in bits
+ * @start: The bitnumber to start searching at
+ * @nr: The number of zeroed bits we're looking for
+ * @data: data for alignment
+ * @pool: pool to get order from
+ * @start_addr: not used in this function
+ */
+unsigned long gen_pool_fixed_alloc(unsigned long *map, unsigned long size,
+ unsigned long start, unsigned int nr, void *data,
+ struct gen_pool *pool, unsigned long start_addr)
+{
+ struct genpool_data_fixed *fixed_data;
+ int order;
+ unsigned long offset_bit;
+ unsigned long start_bit;
+
+ fixed_data = data;
+ order = pool->min_alloc_order;
+ offset_bit = fixed_data->offset >> order;
+ if (WARN_ON(fixed_data->offset & ((1UL << order) - 1)))
+ return size;
+
+ start_bit = bitmap_find_next_zero_area(map, size,
+ start + offset_bit, nr, 0);
+ if (start_bit != offset_bit)
+ start_bit = size;
+ return start_bit;
+}
+EXPORT_SYMBOL(gen_pool_fixed_alloc);
+
+/**
+ * gen_pool_first_fit_order_align - find the first available region
+ * of memory matching the size requirement. The region will be aligned
+ * to the order of the size specified.
+ * @map: The address to base the search on
+ * @size: The bitmap size in bits
+ * @start: The bitnumber to start searching at
+ * @nr: The number of zeroed bits we're looking for
+ * @data: additional data - unused
+ * @pool: pool to find the fit region memory from
+ * @start_addr: not used in this function
+ */
+unsigned long gen_pool_first_fit_order_align(unsigned long *map,
+ unsigned long size, unsigned long start,
+ unsigned int nr, void *data, struct gen_pool *pool,
+ unsigned long start_addr)
+{
+ unsigned long align_mask = roundup_pow_of_two(nr) - 1;
+
+ return bitmap_find_next_zero_area(map, size, start, nr, align_mask);
+}
+EXPORT_SYMBOL(gen_pool_first_fit_order_align);
+
+/**
+ * gen_pool_best_fit - find the best fitting region of memory
+ * matching the size requirement (no alignment constraint)
+ * @map: The address to base the search on
+ * @size: The bitmap size in bits
+ * @start: The bitnumber to start searching at
+ * @nr: The number of zeroed bits we're looking for
+ * @data: additional data - unused
+ * @pool: pool to find the fit region memory from
+ * @start_addr: not used in this function
+ *
+ * Iterate over the bitmap to find the smallest free region
+ * which we can allocate the memory.
+ */
+unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size,
+ unsigned long start, unsigned int nr, void *data,
+ struct gen_pool *pool, unsigned long start_addr)
+{
+ unsigned long start_bit = size;
+ unsigned long len = size + 1;
+ unsigned long index;
+
+ index = bitmap_find_next_zero_area(map, size, start, nr, 0);
+
+ while (index < size) {
+ unsigned long next_bit = find_next_bit(map, size, index + nr);
+ if ((next_bit - index) < len) {
+ len = next_bit - index;
+ start_bit = index;
+ if (len == nr)
+ return start_bit;
+ }
+ index = bitmap_find_next_zero_area(map, size,
+ next_bit + 1, nr, 0);
+ }
+
+ return start_bit;
+}
+EXPORT_SYMBOL(gen_pool_best_fit);
+
+static void devm_gen_pool_release(struct device *dev, void *res)
+{
+ gen_pool_destroy(*(struct gen_pool **)res);
+}
+
+static int devm_gen_pool_match(struct device *dev, void *res, void *data)
+{
+ struct gen_pool **p = res;
+
+ /* NULL data matches only a pool without an assigned name */
+ if (!data && !(*p)->name)
+ return 1;
+
+ if (!data || !(*p)->name)
+ return 0;
+
+ return !strcmp((*p)->name, data);
+}
+
+/**
+ * gen_pool_get - Obtain the gen_pool (if any) for a device
+ * @dev: device to retrieve the gen_pool from
+ * @name: name of a gen_pool or NULL, identifies a particular gen_pool on device
+ *
+ * Returns the gen_pool for the device if one is present, or NULL.
+ */
+struct gen_pool *gen_pool_get(struct device *dev, const char *name)
+{
+ struct gen_pool **p;
+
+ p = devres_find(dev, devm_gen_pool_release, devm_gen_pool_match,
+ (void *)name);
+ if (!p)
+ return NULL;
+ return *p;
+}
+EXPORT_SYMBOL_GPL(gen_pool_get);
+
+/**
+ * devm_gen_pool_create - managed gen_pool_create
+ * @dev: device that provides the gen_pool
+ * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents
+ * @nid: node selector for allocated gen_pool, %NUMA_NO_NODE for all nodes
+ * @name: name of a gen_pool or NULL, identifies a particular gen_pool on device
+ *
+ * Create a new special memory pool that can be used to manage special purpose
+ * memory not managed by the regular kmalloc/kfree interface. The pool will be
+ * automatically destroyed by the device management code.
+ */
+struct gen_pool *devm_gen_pool_create(struct device *dev, int min_alloc_order,
+ int nid, const char *name)
+{
+ struct gen_pool **ptr, *pool;
+ const char *pool_name = NULL;
+
+ /* Check that genpool to be created is uniquely addressed on device */
+ if (gen_pool_get(dev, name))
+ return ERR_PTR(-EINVAL);
+
+ if (name) {
+ pool_name = kstrdup_const(name, GFP_KERNEL);
+ if (!pool_name)
+ return ERR_PTR(-ENOMEM);
+ }
+
+ ptr = devres_alloc(devm_gen_pool_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ goto free_pool_name;
+
+ pool = gen_pool_create(min_alloc_order, nid);
+ if (!pool)
+ goto free_devres;
+
+ *ptr = pool;
+ pool->name = pool_name;
+ devres_add(dev, ptr);
+
+ return pool;
+
+free_devres:
+ devres_free(ptr);
+free_pool_name:
+ kfree_const(pool_name);
+
+ return ERR_PTR(-ENOMEM);
+}
+EXPORT_SYMBOL(devm_gen_pool_create);
+
+#ifdef CONFIG_OF
+/**
+ * of_gen_pool_get - find a pool by phandle property
+ * @np: device node
+ * @propname: property name containing phandle(s)
+ * @index: index into the phandle array
+ *
+ * Returns the pool that contains the chunk starting at the physical
+ * address of the device tree node pointed at by the phandle property,
+ * or NULL if not found.
+ */
+struct gen_pool *of_gen_pool_get(struct device_node *np,
+ const char *propname, int index)
+{
+ struct platform_device *pdev;
+ struct device_node *np_pool, *parent;
+ const char *name = NULL;
+ struct gen_pool *pool = NULL;
+
+ np_pool = of_parse_phandle(np, propname, index);
+ if (!np_pool)
+ return NULL;
+
+ pdev = of_find_device_by_node(np_pool);
+ if (!pdev) {
+ /* Check if named gen_pool is created by parent node device */
+ parent = of_get_parent(np_pool);
+ pdev = of_find_device_by_node(parent);
+ of_node_put(parent);
+
+ of_property_read_string(np_pool, "label", &name);
+ if (!name)
+ name = np_pool->name;
+ }
+ if (pdev)
+ pool = gen_pool_get(&pdev->dev, name);
+ of_node_put(np_pool);
+
+ return pool;
+}
+EXPORT_SYMBOL_GPL(of_gen_pool_get);
+#endif /* CONFIG_OF */