* Vitaly Wool <vitaly.wool@xxxxxxxxxxx> [250709 13:24]: > Reimplement vrealloc() to be able to set node and alignment should > a user need to do so. Rename the function to vrealloc_node_align() > to better match what it actually does now and introduce macros for > vrealloc() and friends for backward compatibility. > > With that change we also provide the ability for the Rust part of > the kernel to set node and alignment in its allocations. > > Signed-off-by: Vitaly Wool <vitaly.wool@xxxxxxxxxxx> > Reviewed-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx> > Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx> > --- > include/linux/vmalloc.h | 12 +++++++++--- > mm/nommu.c | 3 ++- > mm/vmalloc.c | 31 ++++++++++++++++++++++++++----- > 3 files changed, 37 insertions(+), 9 deletions(-) > ... > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index 6dbcdceecae1..03dd06097b25 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -4089,19 +4089,31 @@ void *vzalloc_node_noprof(unsigned long size, int node) > EXPORT_SYMBOL(vzalloc_node_noprof); > > /** > - * vrealloc - reallocate virtually contiguous memory; contents remain unchanged > + * vrealloc_node_align_noprof - reallocate virtually contiguous memory; contents > + * remain unchanged > * @p: object to reallocate memory for > * @size: the size to reallocate > + * @align: requested alignment > * @flags: the flags for the page level allocator > + * @nid: node number of the target node > + * > + * If @p is %NULL, vrealloc_XXX() behaves exactly like vmalloc(). If @size is > + * 0 and @p is not a %NULL pointer, the object pointed to is freed. > * > - * If @p is %NULL, vrealloc() behaves exactly like vmalloc(). If @size is 0 and > - * @p is not a %NULL pointer, the object pointed to is freed. > + * if @nid is not NUMA_NO_NODE, this function will try to allocate memory on > + * the given node. If reallocation is not necessary (e. g. the new size is less > + * than the current allocated size), the current allocation will be preserved > + * unless __GFP_THISNODE is set. In the latter case a new allocation on the > + * requested node will be attempted. I am having a very hard time understanding what you mean here. What is the latter case? If @nis is !NUMA_NO_NODE, the allocation will be attempted on the given node. Then things sort of get confusing. What is the latter case? > * > * If __GFP_ZERO logic is requested, callers must ensure that, starting with the > * initial memory allocation, every subsequent call to this API for the same > * memory allocation is flagged with __GFP_ZERO. Otherwise, it is possible that > * __GFP_ZERO is not fully honored by this API. > * > + * If the requested alignment is bigger than the one the *existing* allocation > + * has, this function will fail. > + * It might be better to say something like: Requesting an alignment that is bigger than the alignment of the *existing* allocation will fail. ... Thanks, Liam
