Messages in this thread Patch in this message |  | | From | Liam Howlett <> | Subject | [PATCH v11 36/69] xtensa: remove vma linked list walks | Date | Sun, 17 Jul 2022 02:46:49 +0000 |
| |
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Use the VMA iterator instead. Since VMA can no longer be NULL in the loop, then deal with out-of-memory outside the loop. This means a slightly longer run time in the failure case (-ENOMEM) - it will run to the end of the VMAs before erroring instead of in the middle of the loop.
Link: https://lkml.kernel.org/r/20220504011345.662299-21-Liam.Howlett@oracle.com Link: https://lkml.kernel.org/r/20220621204632.3370049-37-Liam.Howlett@oracle.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Howells <dhowells@redhat.com> Cc: SeongJae Park <sj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> --- arch/xtensa/kernel/syscall.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/arch/xtensa/kernel/syscall.c b/arch/xtensa/kernel/syscall.c index 201356faa7e6..b3c2450d6f23 100644 --- a/arch/xtensa/kernel/syscall.c +++ b/arch/xtensa/kernel/syscall.c @@ -58,6 +58,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags) { struct vm_area_struct *vmm; + struct vma_iterator vmi; if (flags & MAP_FIXED) { /* We do not accept a shared mapping if it would violate @@ -79,15 +80,20 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, else addr = PAGE_ALIGN(addr); - for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) { - /* At this point: (!vmm || addr < vmm->vm_end). */ - if (TASK_SIZE - len < addr) - return -ENOMEM; - if (!vmm || addr + len <= vm_start_gap(vmm)) - return addr; + vma_iter_init(&vmi, current->mm, addr); + for_each_vma(vmi, vmm) { + /* At this point: (addr < vmm->vm_end). */ + if (addr + len <= vm_start_gap(vmm)) + break; + addr = vmm->vm_end; if (flags & MAP_SHARED) addr = COLOUR_ALIGN(addr, pgoff); } + + if (TASK_SIZE - len < addr) + return -ENOMEM; + + return addr; } #endif -- 2.35.1
|  |