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int gen_pool_add_owner(struct gen_pool *pool, unsigned long virt, phys_addr_t phys,// 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> */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 int bitmap_set_ll(unsigned long *map, int start, int nr){ unsigned long *p = map + BIT_WORD(start); const int 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 >= 0) { if (set_bits_ll(p, mask_to_set))