| Message ID | 20240531163217.1584450-5-Liam.Howlett@oracle.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Avoid MAP_FIXED gap exposure | expand |
On Fri, May 31, 2024 at 9:33 AM Liam R. Howlett <Liam.Howlett@oracle.com> wrote: > > 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 reduce to almost nothing. The remains of the function can be added > to vms_complete_munmap_vmas(). > > Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> > --- > mm/internal.h | 6 ++++ > mm/mmap.c | 85 +++++++++++++++++++++++++++------------------------ > 2 files changed, 51 insertions(+), 40 deletions(-) > > diff --git a/mm/internal.h b/mm/internal.h > index 6ebf77853d68..8c02ebf5736c 100644 > --- a/mm/internal.h > +++ b/mm/internal.h > @@ -1435,12 +1435,18 @@ 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 *next; /* vma after the munmap area */ > + struct vm_area_struct *prev; /* vma before the munmap area */ > struct list_head *uf; /* Userfaultfd list_head */ > unsigned long start; /* Aligned start addr */ > unsigned long end; /* Aligned end addr */ > 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 */ > }; > > diff --git a/mm/mmap.c b/mm/mmap.c > index 57f2383245ea..3e0930c09213 100644 > --- a/mm/mmap.c > +++ b/mm/mmap.c > @@ -482,7 +482,8 @@ static inline void init_vma_munmap(struct vma_munmap_struct *vms, > 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; > } > > /* > @@ -604,7 +605,6 @@ static inline void vma_complete(struct vma_prepare *vp, > } > if (vp->insert && vp->file) > uprobe_mmap(vp->insert); > - validate_mm(mm); vma_complete() is used in places other than vma_shrink(). You effectively removed validate_mm() for all those other users. Is that intentional? If so, that should be documented in the changelog. > } > > /* > @@ -733,6 +733,7 @@ int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma, > vma_iter_clear(vmi); > vma_set_range(vma, start, end, pgoff); > vma_complete(&vp, vmi, vma->vm_mm); > + validate_mm(vma->vm_mm); > return 0; > } > > @@ -2347,30 +2348,6 @@ struct vm_area_struct *expand_stack(struct mm_struct *mm, unsigned long addr) > return vma; > } > > -/* > - * 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); > -} > - > /* > * Get rid of page table information in the indicated region. > * > @@ -2625,13 +2602,14 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, > if (error) > 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; > /* Does it split the end? */ > if (next->vm_end > vms->end) { > error = __split_vma(vms->vmi, next, vms->end, 0); > @@ -2640,8 +2618,21 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, > } > vma_start_write(next); > mas_set(mas_detach, vms->vma_count++); > + 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; > > error = mas_store_gfp(mas_detach, next, GFP_KERNEL); > if (error) > @@ -2667,7 +2658,9 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, > 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. */ > @@ -2712,10 +2705,11 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, > * @mas_detach: The maple state of the detached vmas > * > */ > +static inline void vms_vm_stat_account(struct vma_munmap_struct *vms); > 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; > @@ -2724,21 +2718,21 @@ static void vms_complete_munmap_vmas(struct vma_munmap_struct *vms, > 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); > + vms_vm_stat_account(vms); > 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); > @@ -3631,6 +3625,17 @@ void vm_stat_account(struct mm_struct *mm, vm_flags_t flags, long npages) > mm->data_vm += npages; > } > > +/* Accounting for munmap */ > +static inline void vms_vm_stat_account(struct vma_munmap_struct *vms) > +{ > + struct mm_struct *mm = vms->mm; > + > + WRITE_ONCE(mm->total_vm, READ_ONCE(mm->total_vm) - vms->nr_pages); > + mm->exec_vm -= vms->exec_vm; > + mm->stack_vm -= vms->stack_vm; > + mm->data_vm -= vms->data_vm; > +} > + > static vm_fault_t special_mapping_fault(struct vm_fault *vmf); > > /* > -- > 2.43.0 >
* Suren Baghdasaryan <surenb@google.com> [240607 10:38]: > On Fri, May 31, 2024 at 9:33 AM Liam R. Howlett <Liam.Howlett@oracle.com> wrote: > > > > 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 reduce to almost nothing. The remains of the function can be added > > to vms_complete_munmap_vmas(). > > > > Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> > > --- > > mm/internal.h | 6 ++++ > > mm/mmap.c | 85 +++++++++++++++++++++++++++------------------------ > > 2 files changed, 51 insertions(+), 40 deletions(-) > > > > diff --git a/mm/internal.h b/mm/internal.h > > index 6ebf77853d68..8c02ebf5736c 100644 > > --- a/mm/internal.h > > +++ b/mm/internal.h > > @@ -1435,12 +1435,18 @@ 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 *next; /* vma after the munmap area */ > > + struct vm_area_struct *prev; /* vma before the munmap area */ > > struct list_head *uf; /* Userfaultfd list_head */ > > unsigned long start; /* Aligned start addr */ > > unsigned long end; /* Aligned end addr */ > > 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 */ > > }; > > > > diff --git a/mm/mmap.c b/mm/mmap.c > > index 57f2383245ea..3e0930c09213 100644 > > --- a/mm/mmap.c > > +++ b/mm/mmap.c > > @@ -482,7 +482,8 @@ static inline void init_vma_munmap(struct vma_munmap_struct *vms, > > 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; > > } > > > > /* > > @@ -604,7 +605,6 @@ static inline void vma_complete(struct vma_prepare *vp, > > } > > if (vp->insert && vp->file) > > uprobe_mmap(vp->insert); > > - validate_mm(mm); > > vma_complete() is used in places other than vma_shrink(). You > effectively removed validate_mm() for all those other users. Is that > intentional? If so, that should be documented in the changelog. Oh, right. Yes. This needs to be extracted into its own patch. We cannot validate_mm() in vma_complete() due to vma_expand() being called prior to the completion of the MAP_FIXED munmap. I will extract this into its own patch for the next revision. > > > } > > > > /* > > @@ -733,6 +733,7 @@ int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma, > > vma_iter_clear(vmi); > > vma_set_range(vma, start, end, pgoff); > > vma_complete(&vp, vmi, vma->vm_mm); > > + validate_mm(vma->vm_mm); > > return 0; > > } > > > > @@ -2347,30 +2348,6 @@ struct vm_area_struct *expand_stack(struct mm_struct *mm, unsigned long addr) > > return vma; > > } > > > > -/* > > - * 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); > > -} > > - > > /* > > * Get rid of page table information in the indicated region. > > * > > @@ -2625,13 +2602,14 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, > > if (error) > > 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; > > /* Does it split the end? */ > > if (next->vm_end > vms->end) { > > error = __split_vma(vms->vmi, next, vms->end, 0); > > @@ -2640,8 +2618,21 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, > > } > > vma_start_write(next); > > mas_set(mas_detach, vms->vma_count++); > > + 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; > > > > error = mas_store_gfp(mas_detach, next, GFP_KERNEL); > > if (error) > > @@ -2667,7 +2658,9 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, > > 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. */ > > @@ -2712,10 +2705,11 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, > > * @mas_detach: The maple state of the detached vmas > > * > > */ > > +static inline void vms_vm_stat_account(struct vma_munmap_struct *vms); > > 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; > > @@ -2724,21 +2718,21 @@ static void vms_complete_munmap_vmas(struct vma_munmap_struct *vms, > > 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); > > + vms_vm_stat_account(vms); > > 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); > > @@ -3631,6 +3625,17 @@ void vm_stat_account(struct mm_struct *mm, vm_flags_t flags, long npages) > > mm->data_vm += npages; > > } > > > > +/* Accounting for munmap */ > > +static inline void vms_vm_stat_account(struct vma_munmap_struct *vms) > > +{ > > + struct mm_struct *mm = vms->mm; > > + > > + WRITE_ONCE(mm->total_vm, READ_ONCE(mm->total_vm) - vms->nr_pages); > > + mm->exec_vm -= vms->exec_vm; > > + mm->stack_vm -= vms->stack_vm; > > + mm->data_vm -= vms->data_vm; > > +} > > + > > static vm_fault_t special_mapping_fault(struct vm_fault *vmf); > > > > /* > > -- > > 2.43.0 > > >
diff --git a/mm/internal.h b/mm/internal.h index 6ebf77853d68..8c02ebf5736c 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1435,12 +1435,18 @@ 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 *next; /* vma after the munmap area */ + struct vm_area_struct *prev; /* vma before the munmap area */ struct list_head *uf; /* Userfaultfd list_head */ unsigned long start; /* Aligned start addr */ unsigned long end; /* Aligned end addr */ 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 */ }; diff --git a/mm/mmap.c b/mm/mmap.c index 57f2383245ea..3e0930c09213 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -482,7 +482,8 @@ static inline void init_vma_munmap(struct vma_munmap_struct *vms, 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; } /* @@ -604,7 +605,6 @@ static inline void vma_complete(struct vma_prepare *vp, } if (vp->insert && vp->file) uprobe_mmap(vp->insert); - validate_mm(mm); } /* @@ -733,6 +733,7 @@ int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma, vma_iter_clear(vmi); vma_set_range(vma, start, end, pgoff); vma_complete(&vp, vmi, vma->vm_mm); + validate_mm(vma->vm_mm); return 0; } @@ -2347,30 +2348,6 @@ struct vm_area_struct *expand_stack(struct mm_struct *mm, unsigned long addr) return vma; } -/* - * 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); -} - /* * Get rid of page table information in the indicated region. * @@ -2625,13 +2602,14 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, if (error) 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; /* Does it split the end? */ if (next->vm_end > vms->end) { error = __split_vma(vms->vmi, next, vms->end, 0); @@ -2640,8 +2618,21 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, } vma_start_write(next); mas_set(mas_detach, vms->vma_count++); + 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; error = mas_store_gfp(mas_detach, next, GFP_KERNEL); if (error) @@ -2667,7 +2658,9 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, 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. */ @@ -2712,10 +2705,11 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, * @mas_detach: The maple state of the detached vmas * */ +static inline void vms_vm_stat_account(struct vma_munmap_struct *vms); 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; @@ -2724,21 +2718,21 @@ static void vms_complete_munmap_vmas(struct vma_munmap_struct *vms, 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); + vms_vm_stat_account(vms); 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); @@ -3631,6 +3625,17 @@ void vm_stat_account(struct mm_struct *mm, vm_flags_t flags, long npages) mm->data_vm += npages; } +/* Accounting for munmap */ +static inline void vms_vm_stat_account(struct vma_munmap_struct *vms) +{ + struct mm_struct *mm = vms->mm; + + WRITE_ONCE(mm->total_vm, READ_ONCE(mm->total_vm) - vms->nr_pages); + mm->exec_vm -= vms->exec_vm; + mm->stack_vm -= vms->stack_vm; + mm->data_vm -= vms->data_vm; +} + static vm_fault_t special_mapping_fault(struct vm_fault *vmf); /*
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 reduce to almost nothing. The remains of the function can be added to vms_complete_munmap_vmas(). Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> --- mm/internal.h | 6 ++++ mm/mmap.c | 85 +++++++++++++++++++++++++++------------------------ 2 files changed, 51 insertions(+), 40 deletions(-)