kevin/linux
1
Fork 0
Code

resource: Export find_resource_space()

Browse Source 
PCI bridge window logic needs to find out in advance to the actual
allocation if there is an empty space big enough to fit the window.

Export find_resource_space() for the purpose. Also move the struct
resource_constraint into generic header to be able to use the new
interface.

Link: https://lore.kernel.org/r/20240507102523.57320-7-ilpo.jarvinen@linux.intel.com
Tested-by: Lidong Wang <lidong.wang@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
This commit is contained in:
Ilpo Järvinen 2024-05-07 13:25:21 +03:00 committed by Bjorn Helgaas
parent 094c0ce545
commit 2700225304
2 changed files with 26 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
include/linux/ioport.h
View File

@ -205,6 +205,25 @@ typedef resource_size_t (*resource_alignf)(void *data,
resource_size_t size,
resource_size_t align);
/**
* struct resource_constraint - constraints to be met while searching empty
* resource space
* @min: The minimum address for the memory range
* @max: The maximum address for the memory range
* @align: Alignment for the start address of the empty space
* @alignf: Additional alignment constraints callback
* @alignf_data: Data provided for @alignf callback
*
* Contains the range and alignment constraints that have to be met during
* find_resource_space(). @alignf can be NULL indicating no alignment beyond
* @align is necessary.
*/
struct resource_constraint {
resource_size_t min, max, align;
resource_alignf alignf;
void *alignf_data;
};
/* PC/ISA/whatever - the normal PC address spaces: IO and memory */
extern struct resource ioport_resource;
extern struct resource iomem_resource;
@ -278,6 +297,9 @@ static inline bool resource_union(const struct resource *r1, const struct resour
return true;
}
int find_resource_space(struct resource *root, struct resource *new,
resource_size_t size, struct resource_constraint *constraint);
/* Convenience shorthand with allocation */
#define request_region(start,n,name) __request_region(&ioport_resource, (start), (n), (name), 0)
#define request_muxed_region(start,n,name) __request_region(&ioport_resource, (start), (n), (name), IORESOURCE_MUXED)

26
kernel/resource.c
View File

@ -48,25 +48,6 @@ struct resource iomem_resource = {
};
EXPORT_SYMBOL(iomem_resource);
/**
* struct resource_constraint - constraints to be met while searching empty
* resource space
* @min: The minimum address for the memory range
* @max: The maximum address for the memory range
* @align: Alignment for the start address of the empty space
* @alignf: Additional alignment constraints callback
* @alignf_data: Data provided for @alignf callback
*
* Contains the range and alignment constraints that have to be met during
* find_resource_space(). @alignf can be NULL indicating no alignment beyond
* @align is necessary.
*/
struct resource_constraint {
resource_size_t min, max, align;
resource_alignf alignf;
void *alignf_data;
};
static DEFINE_RWLOCK(resource_lock);
static struct resource *next_resource(struct resource *p, bool skip_children)
@ -708,12 +689,13 @@ next: if (!this || this->end == root->end)
* * %0 - if successful, @new members start, end, and flags are altered.
* * %-EBUSY - if no empty space was found.
*/
static int find_resource_space(struct resource *root, struct resource *new,
resource_size_t size,
struct resource_constraint *constraint)
int find_resource_space(struct resource *root, struct resource *new,
resource_size_t size,
struct resource_constraint *constraint)
{
return __find_resource_space(root, NULL, new, size, constraint);
}
EXPORT_SYMBOL_GPL(find_resource_space);
/**
* reallocate_resource - allocate a slot in the resource tree given range & alignment.