From 182ea1d71750ff9a41e7f8225c842246a4375983 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Tue, 6 Sep 2022 19:48:56 +0000 Subject: coredump: remove vma linked list walk Use the Maple Tree iterator instead. This is too complicated for the VMA iterator to handle, so let's open-code it for now. If this turns out to be a common pattern, we can migrate it to common code. Link: https://lkml.kernel.org/r/20220906194824.2110408-41-Liam.Howlett@oracle.com Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Liam R. Howlett Tested-by: Yu Zhao Cc: Catalin Marinas Cc: David Hildenbrand Cc: David Howells Cc: Davidlohr Bueso Cc: SeongJae Park Cc: Sven Schnelle Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton --- fs/coredump.c | 34 ++++++++++++---------------------- 1 file changed, 12 insertions(+), 22 deletions(-) (limited to 'fs/coredump.c') diff --git a/fs/coredump.c b/fs/coredump.c index 9f4aae202109..35f2af85b9bc 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -1072,30 +1072,20 @@ whole: return vma->vm_end - vma->vm_start; } -static struct vm_area_struct *first_vma(struct task_struct *tsk, - struct vm_area_struct *gate_vma) -{ - struct vm_area_struct *ret = tsk->mm->mmap; - - if (ret) - return ret; - return gate_vma; -} - /* * Helper function for iterating across a vma list. It ensures that the caller * will visit `gate_vma' prior to terminating the search. */ -static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma, +static struct vm_area_struct *coredump_next_vma(struct ma_state *mas, + struct vm_area_struct *vma, struct vm_area_struct *gate_vma) { - struct vm_area_struct *ret; - - ret = this_vma->vm_next; - if (ret) - return ret; - if (this_vma == gate_vma) + if (gate_vma && (vma == gate_vma)) return NULL; + + vma = mas_next(mas, ULONG_MAX); + if (vma) + return vma; return gate_vma; } @@ -1119,9 +1109,10 @@ static void free_vma_snapshot(struct coredump_params *cprm) */ static bool dump_vma_snapshot(struct coredump_params *cprm) { - struct vm_area_struct *vma, *gate_vma; + struct vm_area_struct *gate_vma, *vma = NULL; struct mm_struct *mm = current->mm; - int i; + MA_STATE(mas, &mm->mm_mt, 0, 0); + int i = 0; /* * Once the stack expansion code is fixed to not change VMA bounds @@ -1141,8 +1132,7 @@ static bool dump_vma_snapshot(struct coredump_params *cprm) return false; } - for (i = 0, vma = first_vma(current, gate_vma); vma != NULL; - vma = next_vma(vma, gate_vma), i++) { + while ((vma = coredump_next_vma(&mas, vma, gate_vma)) != NULL) { struct core_vma_metadata *m = cprm->vma_meta + i; m->start = vma->vm_start; @@ -1150,10 +1140,10 @@ static bool dump_vma_snapshot(struct coredump_params *cprm) m->flags = vma->vm_flags; m->dump_size = vma_dump_size(vma, cprm->mm_flags); m->pgoff = vma->vm_pgoff; - m->file = vma->vm_file; if (m->file) get_file(m->file); + i++; } mmap_write_unlock(mm); -- cgit v1.2.3