On 2/17/20 1:54 PM, Heinrich Schuchardt wrote: > Provide descriptions of: > > * efi_get_memory_map() > * efi_low_alloc_above() > * efi_free() > > Signed-off-by: Heinrich Schuchardt <xypron.glpk@xxxxxx> > --- > v2: > point out how efi_free() is rounding up the memory size > --- > drivers/firmware/efi/libstub/mem.c | 36 ++++++++++++++++++++++++++++-- > 1 file changed, 34 insertions(+), 2 deletions(-) > > diff --git a/drivers/firmware/efi/libstub/mem.c b/drivers/firmware/efi/libstub/mem.c > index c25fd9174b74..49116b9b0801 100644 > --- a/drivers/firmware/efi/libstub/mem.c > +++ b/drivers/firmware/efi/libstub/mem.c > @@ -16,6 +16,15 @@ static inline bool mmap_has_headroom(unsigned long buff_size, > return slack / desc_size >= EFI_MMAP_NR_SLACK_SLOTS; > } > Hi, Please use proper kernel-doc notation. See below... > +/** > + * efi_get_memory_map() - get memory map > + * @map on return pointer to memory map * @map: > + * > + * Retrieve the UEFI memory map. The allocated memory leaves room for > + * up to EFI_MMAP_NR_SLACK_SLOTS additional memory map entries. > + * > + * Return: status code > + */ > efi_status_t efi_get_memory_map(struct efi_boot_memmap *map) > { > efi_memory_desc_t *m = NULL; > @@ -109,8 +118,20 @@ efi_status_t efi_allocate_pages(unsigned long size, unsigned long *addr, > } > return EFI_SUCCESS; > } > -/* > - * Allocate at the lowest possible address that is not below 'min'. > +/** > + * efi_low_alloc_above() - allocate pages at or above given address > + * @size: size of the memory area to allocate > + * @align: minimum alignment of the allocated memory area. It should > + * a power of two. > + * @addr: on exit the address of the allocated memory > + * @min: minimum address to used for the memory allocation > + * > + * Allocate at the lowest possible address that is not below 'min' as > + * EFI_LOADER_DATA. The allocated pages are aligned according to 'align' but at > + * least EFI_ALLOC_ALIGN. The first allocated page will not below the address > + * given by 'min'. > + * > + * Return: status code > */ > efi_status_t efi_low_alloc_above(unsigned long size, unsigned long align, > unsigned long *addr, unsigned long min) > @@ -187,6 +208,17 @@ efi_status_t efi_low_alloc_above(unsigned long size, unsigned long align, > return status; > } > > +/** > + * efi_free() - free memory pages > + * @size size of the memory area to free in bytes * @size: * @addr: > + * @addr start of the memory area to free (must be EFI_PAGE_SIZE > + * aligned) > + * > + * 'size' is rounded up to a multiple of EFI_ALLOC_ALIGN which is an > + * architecture specific multiple of EFI_PAGE_SIZE. So this function should > + * only be used to return pages allocated with efi_allocate_pages() or > + * efi_low_alloc_above(). > + */ > void efi_free(unsigned long size, unsigned long addr) > { > unsigned long nr_pages; > -- > 2.25.0 > Thanks. -- ~Randy