diff options
Diffstat (limited to 'drivers/xen/unpopulated-alloc.c')
| -rw-r--r-- | drivers/xen/unpopulated-alloc.c | 87 |
1 files changed, 82 insertions, 5 deletions
diff --git a/drivers/xen/unpopulated-alloc.c b/drivers/xen/unpopulated-alloc.c index 87e6b7db892f..a8b41057c382 100644 --- a/drivers/xen/unpopulated-alloc.c +++ b/drivers/xen/unpopulated-alloc.c @@ -8,6 +8,7 @@ #include <asm/page.h> +#include <xen/balloon.h> #include <xen/page.h> #include <xen/xen.h> @@ -15,13 +16,29 @@ static DEFINE_MUTEX(list_lock); static struct page *page_list; static unsigned int list_count; +static struct resource *target_resource; + +/* + * If arch is not happy with system "iomem_resource" being used for + * the region allocation it can provide it's own view by creating specific + * Xen resource with unused regions of guest physical address space provided + * by the hypervisor. + */ +int __weak __init arch_xen_unpopulated_init(struct resource **res) +{ + *res = &iomem_resource; + + return 0; +} + static int fill_list(unsigned int nr_pages) { struct dev_pagemap *pgmap; - struct resource *res; + struct resource *res, *tmp_res = NULL; void *vaddr; unsigned int i, alloc_pages = round_up(nr_pages, PAGES_PER_SECTION); - int ret = -ENOMEM; + struct range mhp_range; + int ret; res = kzalloc(sizeof(*res), GFP_KERNEL); if (!res) @@ -30,14 +47,40 @@ static int fill_list(unsigned int nr_pages) res->name = "Xen scratch"; res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; - ret = allocate_resource(&iomem_resource, res, - alloc_pages * PAGE_SIZE, 0, -1, + mhp_range = mhp_get_pluggable_range(true); + + ret = allocate_resource(target_resource, res, + alloc_pages * PAGE_SIZE, mhp_range.start, mhp_range.end, PAGES_PER_SECTION * PAGE_SIZE, NULL, NULL); if (ret < 0) { pr_err("Cannot allocate new IOMEM resource\n"); goto err_resource; } + /* + * Reserve the region previously allocated from Xen resource to avoid + * re-using it by someone else. + */ + if (target_resource != &iomem_resource) { + tmp_res = kzalloc(sizeof(*tmp_res), GFP_KERNEL); + if (!tmp_res) { + ret = -ENOMEM; + goto err_insert; + } + + tmp_res->name = res->name; + tmp_res->start = res->start; + tmp_res->end = res->end; + tmp_res->flags = res->flags; + + ret = request_resource(&iomem_resource, tmp_res); + if (ret < 0) { + pr_err("Cannot request resource %pR (%d)\n", tmp_res, ret); + kfree(tmp_res); + goto err_insert; + } + } + pgmap = kzalloc(sizeof(*pgmap), GFP_KERNEL); if (!pgmap) { ret = -ENOMEM; @@ -85,7 +128,6 @@ static int fill_list(unsigned int nr_pages) for (i = 0; i < alloc_pages; i++) { struct page *pg = virt_to_page(vaddr + PAGE_SIZE * i); - BUG_ON(!virt_addr_valid(vaddr + PAGE_SIZE * i)); pg->zone_device_data = page_list; page_list = pg; list_count++; @@ -96,6 +138,11 @@ static int fill_list(unsigned int nr_pages) err_memremap: kfree(pgmap); err_pgmap: + if (tmp_res) { + release_resource(tmp_res); + kfree(tmp_res); + } +err_insert: release_resource(res); err_resource: kfree(res); @@ -113,6 +160,14 @@ int xen_alloc_unpopulated_pages(unsigned int nr_pages, struct page **pages) unsigned int i; int ret = 0; + /* + * Fallback to default behavior if we do not have any suitable resource + * to allocate required region from and as the result we won't be able to + * construct pages. + */ + if (!target_resource) + return xen_alloc_ballooned_pages(nr_pages, pages); + mutex_lock(&list_lock); if (list_count < nr_pages) { ret = fill_list(nr_pages - list_count); @@ -160,6 +215,11 @@ void xen_free_unpopulated_pages(unsigned int nr_pages, struct page **pages) { unsigned int i; + if (!target_resource) { + xen_free_ballooned_pages(nr_pages, pages); + return; + } + mutex_lock(&list_lock); for (i = 0; i < nr_pages; i++) { pages[i]->zone_device_data = page_list; @@ -202,3 +262,20 @@ static int __init init(void) } subsys_initcall(init); #endif + +static int __init unpopulated_init(void) +{ + int ret; + + if (!xen_domain()) + return -ENODEV; + + ret = arch_xen_unpopulated_init(&target_resource); + if (ret) { + pr_err("xen:unpopulated: Cannot initialize target resource\n"); + target_resource = NULL; + } + + return ret; +} +early_initcall(unpopulated_init); |