docs/core-api: memory-allocation: remove uses of c:func:
These are no longer needed as the documentation build will automatically add the cross references. Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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@ -88,10 +88,10 @@ Selecting memory allocator
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==========================
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The most straightforward way to allocate memory is to use a function
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from the :c:func:`kmalloc` family. And, to be on the safe side it's
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best to use routines that set memory to zero, like
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:c:func:`kzalloc`. If you need to allocate memory for an array, there
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are :c:func:`kmalloc_array` and :c:func:`kcalloc` helpers.
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from the kmalloc() family. And, to be on the safe side it's best to use
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routines that set memory to zero, like kzalloc(). If you need to
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allocate memory for an array, there are kmalloc_array() and kcalloc()
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helpers.
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The maximal size of a chunk that can be allocated with `kmalloc` is
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limited. The actual limit depends on the hardware and the kernel
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@ -102,29 +102,26 @@ The address of a chunk allocated with `kmalloc` is aligned to at least
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ARCH_KMALLOC_MINALIGN bytes. For sizes which are a power of two, the
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alignment is also guaranteed to be at least the respective size.
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For large allocations you can use :c:func:`vmalloc` and
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:c:func:`vzalloc`, or directly request pages from the page
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allocator. The memory allocated by `vmalloc` and related functions is
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not physically contiguous.
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For large allocations you can use vmalloc() and vzalloc(), or directly
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request pages from the page allocator. The memory allocated by `vmalloc`
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and related functions is not physically contiguous.
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If you are not sure whether the allocation size is too large for
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`kmalloc`, it is possible to use :c:func:`kvmalloc` and its
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derivatives. It will try to allocate memory with `kmalloc` and if the
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allocation fails it will be retried with `vmalloc`. There are
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restrictions on which GFP flags can be used with `kvmalloc`; please
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see :c:func:`kvmalloc_node` reference documentation. Note that
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`kvmalloc` may return memory that is not physically contiguous.
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`kmalloc`, it is possible to use kvmalloc() and its derivatives. It will
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try to allocate memory with `kmalloc` and if the allocation fails it
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will be retried with `vmalloc`. There are restrictions on which GFP
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flags can be used with `kvmalloc`; please see kvmalloc_node() reference
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documentation. Note that `kvmalloc` may return memory that is not
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physically contiguous.
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If you need to allocate many identical objects you can use the slab
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cache allocator. The cache should be set up with
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:c:func:`kmem_cache_create` or :c:func:`kmem_cache_create_usercopy`
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before it can be used. The second function should be used if a part of
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the cache might be copied to the userspace. After the cache is
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created :c:func:`kmem_cache_alloc` and its convenience wrappers can
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allocate memory from that cache.
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cache allocator. The cache should be set up with kmem_cache_create() or
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kmem_cache_create_usercopy() before it can be used. The second function
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should be used if a part of the cache might be copied to the userspace.
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After the cache is created kmem_cache_alloc() and its convenience
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wrappers can allocate memory from that cache.
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When the allocated memory is no longer needed it must be freed. You
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can use :c:func:`kvfree` for the memory allocated with `kmalloc`,
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`vmalloc` and `kvmalloc`. The slab caches should be freed with
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:c:func:`kmem_cache_free`. And don't forget to destroy the cache with
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:c:func:`kmem_cache_destroy`.
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When the allocated memory is no longer needed it must be freed. You can
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use kvfree() for the memory allocated with `kmalloc`, `vmalloc` and
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`kvmalloc`. The slab caches should be freed with kmem_cache_free(). And
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don't forget to destroy the cache with kmem_cache_destroy().
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