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bounds checking for most architectures on SLAB and SLUB. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Kees Cook <kees@outflux.net> iQIcBAABCgAGBQJXl9tlAAoJEIly9N/cbcAm5BoP/ikTtDp2bFw1sn92yHTnIWzl O+dcKVAeRgjfnSvPfb1JITpaM58exQSaDsPBeR0DbVzU1zDdhLcwHHiQupFh98Ka vBZthbrlL/u4NB26enEEW0iyA32BsxYBMnIu0z5ux9RbZflmQwGQ0c0rvy3dJ7/b FzB5ayVST5y/a0m6/sImeeExh78GU9rsMb1XmJRMwlJAy6miDz/F9TP0LnuW6PhG J5XC99ygNJS1pQBLACRsrZw6ImgBxXnWCok6tWPMxFfD+rJBU2//wqS+HozyMWHL iYP7+ytVo/ZVok4114X/V4Oof3a6wqgpBuYrivJ228QO+UsLYbYLo6sZ8kRK7VFm 9GgHo/8rWB1T9lBbSaa7UL5r0dVNNLjFGS42vwV+YlgUMQ1A35VRojO0jUnJSIQU Ug1IxKmylLd0nEcwD8/l3DXeQABsfL8GsoKW0OtdTZtW4RND4gzq34LK6t7hvayF kUkLg1OLNdUJwOi16M/rhugwYFZIMfoxQtjkRXKWN4RZ2QgSHnx2lhqNmRGPAXBG uy21wlzUTfLTqTpoeOyHzJwyF2qf2y4nsziBMhvmlrUvIzW1LIrYUKCNT4HR8Sh5 lC2WMGYuIqaiu+NOF3v6CgvKd9UW+mxMRyPEybH8mEgfm+FLZlWABiBjIUpSEZuB JFfuMv1zlljj/okIQRg8 =USIR -----END PGP SIGNATURE----- Merge tag 'usercopy-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull usercopy protection from Kees Cook: "Tbhis implements HARDENED_USERCOPY verification of copy_to_user and copy_from_user bounds checking for most architectures on SLAB and SLUB" * tag 'usercopy-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: mm: SLUB hardened usercopy support mm: SLAB hardened usercopy support s390/uaccess: Enable hardened usercopy sparc/uaccess: Enable hardened usercopy powerpc/uaccess: Enable hardened usercopy ia64/uaccess: Enable hardened usercopy arm64/uaccess: Enable hardened usercopy ARM: uaccess: Enable hardened usercopy x86/uaccess: Enable hardened usercopy mm: Hardened usercopy mm: Implement stack frame object validation mm: Add is_migrate_cma_page
653 lines
20 KiB
C
653 lines
20 KiB
C
/*
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* Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
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*
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* (C) SGI 2006, Christoph Lameter
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* Cleaned up and restructured to ease the addition of alternative
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* implementations of SLAB allocators.
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* (C) Linux Foundation 2008-2013
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* Unified interface for all slab allocators
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*/
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#ifndef _LINUX_SLAB_H
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#define _LINUX_SLAB_H
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#include <linux/gfp.h>
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#include <linux/types.h>
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#include <linux/workqueue.h>
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/*
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* Flags to pass to kmem_cache_create().
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* The ones marked DEBUG are only valid if CONFIG_DEBUG_SLAB is set.
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*/
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#define SLAB_CONSISTENCY_CHECKS 0x00000100UL /* DEBUG: Perform (expensive) checks on alloc/free */
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#define SLAB_RED_ZONE 0x00000400UL /* DEBUG: Red zone objs in a cache */
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#define SLAB_POISON 0x00000800UL /* DEBUG: Poison objects */
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#define SLAB_HWCACHE_ALIGN 0x00002000UL /* Align objs on cache lines */
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#define SLAB_CACHE_DMA 0x00004000UL /* Use GFP_DMA memory */
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#define SLAB_STORE_USER 0x00010000UL /* DEBUG: Store the last owner for bug hunting */
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#define SLAB_PANIC 0x00040000UL /* Panic if kmem_cache_create() fails */
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/*
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* SLAB_DESTROY_BY_RCU - **WARNING** READ THIS!
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*
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* This delays freeing the SLAB page by a grace period, it does _NOT_
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* delay object freeing. This means that if you do kmem_cache_free()
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* that memory location is free to be reused at any time. Thus it may
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* be possible to see another object there in the same RCU grace period.
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*
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* This feature only ensures the memory location backing the object
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* stays valid, the trick to using this is relying on an independent
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* object validation pass. Something like:
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*
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* rcu_read_lock()
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* again:
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* obj = lockless_lookup(key);
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* if (obj) {
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* if (!try_get_ref(obj)) // might fail for free objects
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* goto again;
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*
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* if (obj->key != key) { // not the object we expected
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* put_ref(obj);
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* goto again;
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* }
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* }
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* rcu_read_unlock();
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*
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* This is useful if we need to approach a kernel structure obliquely,
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* from its address obtained without the usual locking. We can lock
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* the structure to stabilize it and check it's still at the given address,
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* only if we can be sure that the memory has not been meanwhile reused
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* for some other kind of object (which our subsystem's lock might corrupt).
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*
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* rcu_read_lock before reading the address, then rcu_read_unlock after
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* taking the spinlock within the structure expected at that address.
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*/
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#define SLAB_DESTROY_BY_RCU 0x00080000UL /* Defer freeing slabs to RCU */
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#define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */
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#define SLAB_TRACE 0x00200000UL /* Trace allocations and frees */
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/* Flag to prevent checks on free */
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#ifdef CONFIG_DEBUG_OBJECTS
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# define SLAB_DEBUG_OBJECTS 0x00400000UL
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#else
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# define SLAB_DEBUG_OBJECTS 0x00000000UL
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#endif
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#define SLAB_NOLEAKTRACE 0x00800000UL /* Avoid kmemleak tracing */
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/* Don't track use of uninitialized memory */
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#ifdef CONFIG_KMEMCHECK
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# define SLAB_NOTRACK 0x01000000UL
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#else
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# define SLAB_NOTRACK 0x00000000UL
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#endif
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#ifdef CONFIG_FAILSLAB
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# define SLAB_FAILSLAB 0x02000000UL /* Fault injection mark */
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#else
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# define SLAB_FAILSLAB 0x00000000UL
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#endif
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#if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
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# define SLAB_ACCOUNT 0x04000000UL /* Account to memcg */
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#else
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# define SLAB_ACCOUNT 0x00000000UL
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#endif
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#ifdef CONFIG_KASAN
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#define SLAB_KASAN 0x08000000UL
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#else
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#define SLAB_KASAN 0x00000000UL
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#endif
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/* The following flags affect the page allocator grouping pages by mobility */
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#define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */
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#define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
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/*
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* ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
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*
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* Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
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*
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* ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
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* Both make kfree a no-op.
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*/
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#define ZERO_SIZE_PTR ((void *)16)
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#define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
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(unsigned long)ZERO_SIZE_PTR)
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#include <linux/kmemleak.h>
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#include <linux/kasan.h>
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struct mem_cgroup;
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/*
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* struct kmem_cache related prototypes
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*/
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void __init kmem_cache_init(void);
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bool slab_is_available(void);
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struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
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unsigned long,
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void (*)(void *));
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void kmem_cache_destroy(struct kmem_cache *);
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int kmem_cache_shrink(struct kmem_cache *);
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void memcg_create_kmem_cache(struct mem_cgroup *, struct kmem_cache *);
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void memcg_deactivate_kmem_caches(struct mem_cgroup *);
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void memcg_destroy_kmem_caches(struct mem_cgroup *);
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/*
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* Please use this macro to create slab caches. Simply specify the
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* name of the structure and maybe some flags that are listed above.
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*
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* The alignment of the struct determines object alignment. If you
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* f.e. add ____cacheline_aligned_in_smp to the struct declaration
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* then the objects will be properly aligned in SMP configurations.
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*/
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#define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\
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sizeof(struct __struct), __alignof__(struct __struct),\
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(__flags), NULL)
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/*
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* Common kmalloc functions provided by all allocators
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*/
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void * __must_check __krealloc(const void *, size_t, gfp_t);
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void * __must_check krealloc(const void *, size_t, gfp_t);
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void kfree(const void *);
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void kzfree(const void *);
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size_t ksize(const void *);
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#ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR
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const char *__check_heap_object(const void *ptr, unsigned long n,
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struct page *page);
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#else
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static inline const char *__check_heap_object(const void *ptr,
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unsigned long n,
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struct page *page)
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{
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return NULL;
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}
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#endif
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/*
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* Some archs want to perform DMA into kmalloc caches and need a guaranteed
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* alignment larger than the alignment of a 64-bit integer.
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* Setting ARCH_KMALLOC_MINALIGN in arch headers allows that.
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*/
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#if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8
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#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
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#define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN
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#define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN)
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#else
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#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
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#endif
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/*
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* Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
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* Intended for arches that get misalignment faults even for 64 bit integer
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* aligned buffers.
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*/
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#ifndef ARCH_SLAB_MINALIGN
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#define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
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#endif
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/*
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* kmalloc and friends return ARCH_KMALLOC_MINALIGN aligned
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* pointers. kmem_cache_alloc and friends return ARCH_SLAB_MINALIGN
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* aligned pointers.
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*/
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#define __assume_kmalloc_alignment __assume_aligned(ARCH_KMALLOC_MINALIGN)
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#define __assume_slab_alignment __assume_aligned(ARCH_SLAB_MINALIGN)
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#define __assume_page_alignment __assume_aligned(PAGE_SIZE)
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/*
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* Kmalloc array related definitions
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*/
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#ifdef CONFIG_SLAB
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/*
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* The largest kmalloc size supported by the SLAB allocators is
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* 32 megabyte (2^25) or the maximum allocatable page order if that is
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* less than 32 MB.
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*
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* WARNING: Its not easy to increase this value since the allocators have
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* to do various tricks to work around compiler limitations in order to
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* ensure proper constant folding.
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*/
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#define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \
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(MAX_ORDER + PAGE_SHIFT - 1) : 25)
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#define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH
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#ifndef KMALLOC_SHIFT_LOW
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#define KMALLOC_SHIFT_LOW 5
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#endif
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#endif
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#ifdef CONFIG_SLUB
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/*
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* SLUB directly allocates requests fitting in to an order-1 page
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* (PAGE_SIZE*2). Larger requests are passed to the page allocator.
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*/
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#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1)
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#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT)
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#ifndef KMALLOC_SHIFT_LOW
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#define KMALLOC_SHIFT_LOW 3
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#endif
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#endif
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#ifdef CONFIG_SLOB
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/*
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* SLOB passes all requests larger than one page to the page allocator.
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* No kmalloc array is necessary since objects of different sizes can
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* be allocated from the same page.
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*/
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#define KMALLOC_SHIFT_HIGH PAGE_SHIFT
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#define KMALLOC_SHIFT_MAX 30
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#ifndef KMALLOC_SHIFT_LOW
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#define KMALLOC_SHIFT_LOW 3
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#endif
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#endif
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/* Maximum allocatable size */
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#define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX)
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/* Maximum size for which we actually use a slab cache */
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#define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH)
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/* Maximum order allocatable via the slab allocagtor */
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#define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT)
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/*
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* Kmalloc subsystem.
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*/
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#ifndef KMALLOC_MIN_SIZE
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#define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW)
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#endif
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/*
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* This restriction comes from byte sized index implementation.
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* Page size is normally 2^12 bytes and, in this case, if we want to use
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* byte sized index which can represent 2^8 entries, the size of the object
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* should be equal or greater to 2^12 / 2^8 = 2^4 = 16.
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* If minimum size of kmalloc is less than 16, we use it as minimum object
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* size and give up to use byte sized index.
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*/
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#define SLAB_OBJ_MIN_SIZE (KMALLOC_MIN_SIZE < 16 ? \
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(KMALLOC_MIN_SIZE) : 16)
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#ifndef CONFIG_SLOB
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extern struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
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#ifdef CONFIG_ZONE_DMA
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extern struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
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#endif
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/*
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* Figure out which kmalloc slab an allocation of a certain size
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* belongs to.
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* 0 = zero alloc
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* 1 = 65 .. 96 bytes
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* 2 = 129 .. 192 bytes
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* n = 2^(n-1)+1 .. 2^n
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*/
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static __always_inline int kmalloc_index(size_t size)
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{
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if (!size)
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return 0;
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if (size <= KMALLOC_MIN_SIZE)
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return KMALLOC_SHIFT_LOW;
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if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96)
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return 1;
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if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192)
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return 2;
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if (size <= 8) return 3;
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if (size <= 16) return 4;
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if (size <= 32) return 5;
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if (size <= 64) return 6;
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if (size <= 128) return 7;
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if (size <= 256) return 8;
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if (size <= 512) return 9;
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if (size <= 1024) return 10;
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if (size <= 2 * 1024) return 11;
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if (size <= 4 * 1024) return 12;
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if (size <= 8 * 1024) return 13;
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if (size <= 16 * 1024) return 14;
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if (size <= 32 * 1024) return 15;
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if (size <= 64 * 1024) return 16;
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if (size <= 128 * 1024) return 17;
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if (size <= 256 * 1024) return 18;
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if (size <= 512 * 1024) return 19;
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if (size <= 1024 * 1024) return 20;
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if (size <= 2 * 1024 * 1024) return 21;
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if (size <= 4 * 1024 * 1024) return 22;
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if (size <= 8 * 1024 * 1024) return 23;
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if (size <= 16 * 1024 * 1024) return 24;
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if (size <= 32 * 1024 * 1024) return 25;
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if (size <= 64 * 1024 * 1024) return 26;
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BUG();
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/* Will never be reached. Needed because the compiler may complain */
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return -1;
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}
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#endif /* !CONFIG_SLOB */
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void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __malloc;
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void *kmem_cache_alloc(struct kmem_cache *, gfp_t flags) __assume_slab_alignment __malloc;
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void kmem_cache_free(struct kmem_cache *, void *);
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/*
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* Bulk allocation and freeing operations. These are accelerated in an
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* allocator specific way to avoid taking locks repeatedly or building
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* metadata structures unnecessarily.
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*
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* Note that interrupts must be enabled when calling these functions.
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*/
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void kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
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int kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
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/*
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* Caller must not use kfree_bulk() on memory not originally allocated
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* by kmalloc(), because the SLOB allocator cannot handle this.
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*/
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static __always_inline void kfree_bulk(size_t size, void **p)
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{
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kmem_cache_free_bulk(NULL, size, p);
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}
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#ifdef CONFIG_NUMA
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void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignment __malloc;
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void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node) __assume_slab_alignment __malloc;
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#else
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static __always_inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
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{
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return __kmalloc(size, flags);
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}
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static __always_inline void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node)
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{
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return kmem_cache_alloc(s, flags);
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}
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#endif
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#ifdef CONFIG_TRACING
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extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t) __assume_slab_alignment __malloc;
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#ifdef CONFIG_NUMA
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extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
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gfp_t gfpflags,
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int node, size_t size) __assume_slab_alignment __malloc;
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#else
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static __always_inline void *
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kmem_cache_alloc_node_trace(struct kmem_cache *s,
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gfp_t gfpflags,
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int node, size_t size)
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{
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return kmem_cache_alloc_trace(s, gfpflags, size);
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}
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#endif /* CONFIG_NUMA */
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#else /* CONFIG_TRACING */
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static __always_inline void *kmem_cache_alloc_trace(struct kmem_cache *s,
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gfp_t flags, size_t size)
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{
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void *ret = kmem_cache_alloc(s, flags);
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kasan_kmalloc(s, ret, size, flags);
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return ret;
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}
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static __always_inline void *
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kmem_cache_alloc_node_trace(struct kmem_cache *s,
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gfp_t gfpflags,
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int node, size_t size)
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{
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void *ret = kmem_cache_alloc_node(s, gfpflags, node);
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kasan_kmalloc(s, ret, size, gfpflags);
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return ret;
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}
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#endif /* CONFIG_TRACING */
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extern void *kmalloc_order(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
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#ifdef CONFIG_TRACING
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extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
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#else
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static __always_inline void *
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kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
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{
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return kmalloc_order(size, flags, order);
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}
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#endif
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static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
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{
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unsigned int order = get_order(size);
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return kmalloc_order_trace(size, flags, order);
|
|
}
|
|
|
|
/**
|
|
* kmalloc - allocate memory
|
|
* @size: how many bytes of memory are required.
|
|
* @flags: the type of memory to allocate.
|
|
*
|
|
* kmalloc is the normal method of allocating memory
|
|
* for objects smaller than page size in the kernel.
|
|
*
|
|
* The @flags argument may be one of:
|
|
*
|
|
* %GFP_USER - Allocate memory on behalf of user. May sleep.
|
|
*
|
|
* %GFP_KERNEL - Allocate normal kernel ram. May sleep.
|
|
*
|
|
* %GFP_ATOMIC - Allocation will not sleep. May use emergency pools.
|
|
* For example, use this inside interrupt handlers.
|
|
*
|
|
* %GFP_HIGHUSER - Allocate pages from high memory.
|
|
*
|
|
* %GFP_NOIO - Do not do any I/O at all while trying to get memory.
|
|
*
|
|
* %GFP_NOFS - Do not make any fs calls while trying to get memory.
|
|
*
|
|
* %GFP_NOWAIT - Allocation will not sleep.
|
|
*
|
|
* %__GFP_THISNODE - Allocate node-local memory only.
|
|
*
|
|
* %GFP_DMA - Allocation suitable for DMA.
|
|
* Should only be used for kmalloc() caches. Otherwise, use a
|
|
* slab created with SLAB_DMA.
|
|
*
|
|
* Also it is possible to set different flags by OR'ing
|
|
* in one or more of the following additional @flags:
|
|
*
|
|
* %__GFP_COLD - Request cache-cold pages instead of
|
|
* trying to return cache-warm pages.
|
|
*
|
|
* %__GFP_HIGH - This allocation has high priority and may use emergency pools.
|
|
*
|
|
* %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
|
|
* (think twice before using).
|
|
*
|
|
* %__GFP_NORETRY - If memory is not immediately available,
|
|
* then give up at once.
|
|
*
|
|
* %__GFP_NOWARN - If allocation fails, don't issue any warnings.
|
|
*
|
|
* %__GFP_REPEAT - If allocation fails initially, try once more before failing.
|
|
*
|
|
* There are other flags available as well, but these are not intended
|
|
* for general use, and so are not documented here. For a full list of
|
|
* potential flags, always refer to linux/gfp.h.
|
|
*/
|
|
static __always_inline void *kmalloc(size_t size, gfp_t flags)
|
|
{
|
|
if (__builtin_constant_p(size)) {
|
|
if (size > KMALLOC_MAX_CACHE_SIZE)
|
|
return kmalloc_large(size, flags);
|
|
#ifndef CONFIG_SLOB
|
|
if (!(flags & GFP_DMA)) {
|
|
int index = kmalloc_index(size);
|
|
|
|
if (!index)
|
|
return ZERO_SIZE_PTR;
|
|
|
|
return kmem_cache_alloc_trace(kmalloc_caches[index],
|
|
flags, size);
|
|
}
|
|
#endif
|
|
}
|
|
return __kmalloc(size, flags);
|
|
}
|
|
|
|
/*
|
|
* Determine size used for the nth kmalloc cache.
|
|
* return size or 0 if a kmalloc cache for that
|
|
* size does not exist
|
|
*/
|
|
static __always_inline int kmalloc_size(int n)
|
|
{
|
|
#ifndef CONFIG_SLOB
|
|
if (n > 2)
|
|
return 1 << n;
|
|
|
|
if (n == 1 && KMALLOC_MIN_SIZE <= 32)
|
|
return 96;
|
|
|
|
if (n == 2 && KMALLOC_MIN_SIZE <= 64)
|
|
return 192;
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
|
|
{
|
|
#ifndef CONFIG_SLOB
|
|
if (__builtin_constant_p(size) &&
|
|
size <= KMALLOC_MAX_CACHE_SIZE && !(flags & GFP_DMA)) {
|
|
int i = kmalloc_index(size);
|
|
|
|
if (!i)
|
|
return ZERO_SIZE_PTR;
|
|
|
|
return kmem_cache_alloc_node_trace(kmalloc_caches[i],
|
|
flags, node, size);
|
|
}
|
|
#endif
|
|
return __kmalloc_node(size, flags, node);
|
|
}
|
|
|
|
struct memcg_cache_array {
|
|
struct rcu_head rcu;
|
|
struct kmem_cache *entries[0];
|
|
};
|
|
|
|
/*
|
|
* This is the main placeholder for memcg-related information in kmem caches.
|
|
* Both the root cache and the child caches will have it. For the root cache,
|
|
* this will hold a dynamically allocated array large enough to hold
|
|
* information about the currently limited memcgs in the system. To allow the
|
|
* array to be accessed without taking any locks, on relocation we free the old
|
|
* version only after a grace period.
|
|
*
|
|
* Child caches will hold extra metadata needed for its operation. Fields are:
|
|
*
|
|
* @memcg: pointer to the memcg this cache belongs to
|
|
* @root_cache: pointer to the global, root cache, this cache was derived from
|
|
*
|
|
* Both root and child caches of the same kind are linked into a list chained
|
|
* through @list.
|
|
*/
|
|
struct memcg_cache_params {
|
|
bool is_root_cache;
|
|
struct list_head list;
|
|
union {
|
|
struct memcg_cache_array __rcu *memcg_caches;
|
|
struct {
|
|
struct mem_cgroup *memcg;
|
|
struct kmem_cache *root_cache;
|
|
};
|
|
};
|
|
};
|
|
|
|
int memcg_update_all_caches(int num_memcgs);
|
|
|
|
/**
|
|
* kmalloc_array - allocate memory for an array.
|
|
* @n: number of elements.
|
|
* @size: element size.
|
|
* @flags: the type of memory to allocate (see kmalloc).
|
|
*/
|
|
static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
|
|
{
|
|
if (size != 0 && n > SIZE_MAX / size)
|
|
return NULL;
|
|
if (__builtin_constant_p(n) && __builtin_constant_p(size))
|
|
return kmalloc(n * size, flags);
|
|
return __kmalloc(n * size, flags);
|
|
}
|
|
|
|
/**
|
|
* kcalloc - allocate memory for an array. The memory is set to zero.
|
|
* @n: number of elements.
|
|
* @size: element size.
|
|
* @flags: the type of memory to allocate (see kmalloc).
|
|
*/
|
|
static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
|
|
{
|
|
return kmalloc_array(n, size, flags | __GFP_ZERO);
|
|
}
|
|
|
|
/*
|
|
* kmalloc_track_caller is a special version of kmalloc that records the
|
|
* calling function of the routine calling it for slab leak tracking instead
|
|
* of just the calling function (confusing, eh?).
|
|
* It's useful when the call to kmalloc comes from a widely-used standard
|
|
* allocator where we care about the real place the memory allocation
|
|
* request comes from.
|
|
*/
|
|
extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
|
|
#define kmalloc_track_caller(size, flags) \
|
|
__kmalloc_track_caller(size, flags, _RET_IP_)
|
|
|
|
#ifdef CONFIG_NUMA
|
|
extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long);
|
|
#define kmalloc_node_track_caller(size, flags, node) \
|
|
__kmalloc_node_track_caller(size, flags, node, \
|
|
_RET_IP_)
|
|
|
|
#else /* CONFIG_NUMA */
|
|
|
|
#define kmalloc_node_track_caller(size, flags, node) \
|
|
kmalloc_track_caller(size, flags)
|
|
|
|
#endif /* CONFIG_NUMA */
|
|
|
|
/*
|
|
* Shortcuts
|
|
*/
|
|
static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags)
|
|
{
|
|
return kmem_cache_alloc(k, flags | __GFP_ZERO);
|
|
}
|
|
|
|
/**
|
|
* kzalloc - allocate memory. The memory is set to zero.
|
|
* @size: how many bytes of memory are required.
|
|
* @flags: the type of memory to allocate (see kmalloc).
|
|
*/
|
|
static inline void *kzalloc(size_t size, gfp_t flags)
|
|
{
|
|
return kmalloc(size, flags | __GFP_ZERO);
|
|
}
|
|
|
|
/**
|
|
* kzalloc_node - allocate zeroed memory from a particular memory node.
|
|
* @size: how many bytes of memory are required.
|
|
* @flags: the type of memory to allocate (see kmalloc).
|
|
* @node: memory node from which to allocate
|
|
*/
|
|
static inline void *kzalloc_node(size_t size, gfp_t flags, int node)
|
|
{
|
|
return kmalloc_node(size, flags | __GFP_ZERO, node);
|
|
}
|
|
|
|
unsigned int kmem_cache_size(struct kmem_cache *s);
|
|
void __init kmem_cache_init_late(void);
|
|
|
|
#endif /* _LINUX_SLAB_H */
|