The quilt patch titled Subject: mm/vma: change munmap to use vma_munmap_struct() for accounting and surrounding vmas has been removed from the -mm tree. Its filename was mm-vma-change-munmap-to-use-vma_munmap_struct-for-accounting-and-surrounding-vmas.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx> Subject: mm/vma: change munmap to use vma_munmap_struct() for accounting and surrounding vmas Date: Fri, 30 Aug 2024 00:00:46 -0400 Clean up the code by changing the munmap operation to use a structure for the accounting and munmap variables. Since remove_mt() is only called in one location and the contents will be reduced to almost nothing. The remains of the function can be added to vms_complete_munmap_vmas(). Link: https://lkml.kernel.org/r/20240830040101.822209-7-Liam.Howlett@xxxxxxxxxx Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> Reviewed-by: Suren Baghdasaryan <surenb@xxxxxxxxxx> Cc: Bert Karwatzki <spasswolf@xxxxxx> Cc: Jeff Xu <jeffxu@xxxxxxxxxxxx> Cc: Jiri Olsa <olsajiri@xxxxxxxxx> Cc: Kees Cook <kees@xxxxxxxxxx> Cc: Lorenzo Stoakes <lstoakes@xxxxxxxxx> Cc: Mark Brown <broonie@xxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxx> Cc: Paul Moore <paul@xxxxxxxxxxxxxx> Cc: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vma.c | 83 +++++++++++++++++++++++++++-------------------------- mm/vma.h | 6 +++ 2 files changed, 49 insertions(+), 40 deletions(-) --- a/mm/vma.c~mm-vma-change-munmap-to-use-vma_munmap_struct-for-accounting-and-surrounding-vmas +++ a/mm/vma.c @@ -103,7 +103,8 @@ static inline void init_vma_munmap(struc vms->unlock = unlock; vms->uf = uf; vms->vma_count = 0; - vms->nr_pages = vms->locked_vm = 0; + vms->nr_pages = vms->locked_vm = vms->nr_accounted = 0; + vms->exec_vm = vms->stack_vm = vms->data_vm = 0; } /* @@ -300,30 +301,6 @@ static int split_vma(struct vma_iterator } /* - * Ok - we have the memory areas we should free on a maple tree so release them, - * and do the vma updates. - * - * Called with the mm semaphore held. - */ -static inline void remove_mt(struct mm_struct *mm, struct ma_state *mas) -{ - unsigned long nr_accounted = 0; - struct vm_area_struct *vma; - - /* Update high watermark before we lower total_vm */ - update_hiwater_vm(mm); - mas_for_each(mas, vma, ULONG_MAX) { - long nrpages = vma_pages(vma); - - if (vma->vm_flags & VM_ACCOUNT) - nr_accounted += nrpages; - vm_stat_account(mm, vma->vm_flags, -nrpages); - remove_vma(vma, false); - } - vm_unacct_memory(nr_accounted); -} - -/* * init_vma_prep() - Initializer wrapper for vma_prepare struct * @vp: The vma_prepare struct * @vma: The vma that will be altered once locked @@ -722,7 +699,7 @@ static inline void abort_munmap_vmas(str static void vms_complete_munmap_vmas(struct vma_munmap_struct *vms, struct ma_state *mas_detach) { - struct vm_area_struct *prev, *next; + struct vm_area_struct *vma; struct mm_struct *mm; mm = vms->mm; @@ -731,21 +708,31 @@ static void vms_complete_munmap_vmas(str if (vms->unlock) mmap_write_downgrade(mm); - prev = vma_iter_prev_range(vms->vmi); - next = vma_next(vms->vmi); - if (next) - vma_iter_prev_range(vms->vmi); - /* * We can free page tables without write-locking mmap_lock because VMAs * were isolated before we downgraded mmap_lock. */ mas_set(mas_detach, 1); - unmap_region(mm, mas_detach, vms->vma, prev, next, vms->start, vms->end, - vms->vma_count, !vms->unlock); - /* Statistics and freeing VMAs */ + unmap_region(mm, mas_detach, vms->vma, vms->prev, vms->next, + vms->start, vms->end, vms->vma_count, !vms->unlock); + /* Update high watermark before we lower total_vm */ + update_hiwater_vm(mm); + /* Stat accounting */ + WRITE_ONCE(mm->total_vm, READ_ONCE(mm->total_vm) - vms->nr_pages); + /* Paranoid bookkeeping */ + VM_WARN_ON(vms->exec_vm > mm->exec_vm); + VM_WARN_ON(vms->stack_vm > mm->stack_vm); + VM_WARN_ON(vms->data_vm > mm->data_vm); + mm->exec_vm -= vms->exec_vm; + mm->stack_vm -= vms->stack_vm; + mm->data_vm -= vms->data_vm; + + /* Remove and clean up vmas */ mas_set(mas_detach, 0); - remove_mt(mm, mas_detach); + mas_for_each(mas_detach, vma, ULONG_MAX) + remove_vma(vma, false); + + vm_unacct_memory(vms->nr_accounted); validate_mm(mm); if (vms->unlock) mmap_read_unlock(mm); @@ -798,18 +785,19 @@ static int vms_gather_munmap_vmas(struct if (__split_vma(vms->vmi, vms->vma, vms->start, 1)) goto start_split_failed; } + vms->prev = vma_prev(vms->vmi); /* * Detach a range of VMAs from the mm. Using next as a temp variable as * it is always overwritten. */ - next = vms->vma; - do { + for_each_vma_range(*(vms->vmi), next, vms->end) { + long nrpages; + if (!can_modify_vma(next)) { error = -EPERM; goto modify_vma_failed; } - /* Does it split the end? */ if (next->vm_end > vms->end) { if (__split_vma(vms->vmi, next, vms->end, 0)) @@ -821,8 +809,21 @@ static int vms_gather_munmap_vmas(struct goto munmap_gather_failed; vma_mark_detached(next, true); + nrpages = vma_pages(next); + + vms->nr_pages += nrpages; if (next->vm_flags & VM_LOCKED) - vms->locked_vm += vma_pages(next); + vms->locked_vm += nrpages; + + if (next->vm_flags & VM_ACCOUNT) + vms->nr_accounted += nrpages; + + if (is_exec_mapping(next->vm_flags)) + vms->exec_vm += nrpages; + else if (is_stack_mapping(next->vm_flags)) + vms->stack_vm += nrpages; + else if (is_data_mapping(next->vm_flags)) + vms->data_vm += nrpages; if (unlikely(vms->uf)) { /* @@ -842,7 +843,9 @@ static int vms_gather_munmap_vmas(struct BUG_ON(next->vm_start < vms->start); BUG_ON(next->vm_start > vms->end); #endif - } for_each_vma_range(*(vms->vmi), next, vms->end); + } + + vms->next = vma_next(vms->vmi); #if defined(CONFIG_DEBUG_VM_MAPLE_TREE) /* Make sure no VMAs are about to be lost. */ --- a/mm/vma.h~mm-vma-change-munmap-to-use-vma_munmap_struct-for-accounting-and-surrounding-vmas +++ a/mm/vma.h @@ -33,12 +33,18 @@ struct vma_munmap_struct { struct vma_iterator *vmi; struct mm_struct *mm; struct vm_area_struct *vma; /* The first vma to munmap */ + struct vm_area_struct *prev; /* vma before the munmap area */ + struct vm_area_struct *next; /* vma after the munmap area */ struct list_head *uf; /* Userfaultfd list_head */ unsigned long start; /* Aligned start addr (inclusive) */ unsigned long end; /* Aligned end addr (exclusive) */ int vma_count; /* Number of vmas that will be removed */ unsigned long nr_pages; /* Number of pages being removed */ unsigned long locked_vm; /* Number of locked pages */ + unsigned long nr_accounted; /* Number of VM_ACCOUNT pages */ + unsigned long exec_vm; + unsigned long stack_vm; + unsigned long data_vm; bool unlock; /* Unlock after the munmap */ }; _ Patches currently in -mm which might be from Liam.Howlett@xxxxxxxxxx are