LinuxKPI: make __kmalloc() play by the rules

According to Documentation/core-api/dma-api.rst kmalloc() is supposd
to provide physically contiguous memory. [1]

In order to guarantee that allocations are contiguous even if using
PAGE_SIZE or larger check the size and use contigmalloc if needed.
This makes use of 9e6544dd6e (and following) allowing free(9) to
also work for contigmalloced memory.

Sponsored by:	The FreeBSD Foundation
Pointed out by:	jhb [1]
Reviewed by:	jhb, emaste
MFC after:	3 days
Differential Revision: https://reviews.freebsd.org/D46656
This commit is contained in:
Bjoern A. Zeeb 2024-09-12 18:11:01 +00:00
parent a5c7b44d6a
commit 19df0c5abc

View file

@ -215,7 +215,11 @@ lkpi___kmalloc(size_t size, gfp_t flags)
/* sizeof(struct llist_node) is used for kfree_async(). */
_s = MAX(size, sizeof(struct llist_node));
return (malloc(_s, M_KMALLOC, linux_check_m_flags(flags)));
if (_s < PAGE_SIZE)
return (malloc(_s, M_KMALLOC, linux_check_m_flags(flags)));
else
return (contigmalloc(_s, M_KMALLOC, linux_check_m_flags(flags),
0, -1UL, PAGE_SIZE, 0));
}
struct lkpi_kmalloc_ctx {