From 3f31d07571eeea18a7d34db9af21d2285b807a17 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Tue, 29 May 2012 15:06:40 -0700 Subject: [PATCH] mm/fs: route MADV_REMOVE to FALLOC_FL_PUNCH_HOLE Now tmpfs supports hole-punching via fallocate(), switch madvise_remove() to use do_fallocate() instead of vmtruncate_range(): which extends madvise(,,MADV_REMOVE) support from tmpfs to ext4, ocfs2 and xfs. There is one more user of vmtruncate_range() in our tree, staging/android's ashmem_shrink(): convert it to use do_fallocate() too (but if its unpinned areas are already unmapped - I don't know - then it would do better to use shmem_truncate_range() directly). Based-on-patch-by: Cong Wang Signed-off-by: Hugh Dickins Cc: Christoph Hellwig Cc: Al Viro Cc: Colin Cross Cc: John Stultz Cc: Greg Kroah-Hartman Cc: "Theodore Ts'o" Cc: Andreas Dilger Cc: Mark Fasheh Cc: Joel Becker Cc: Dave Chinner Cc: Ben Myers Cc: Michael Kerrisk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/staging/android/ashmem.c | 8 +++++--- mm/madvise.c | 15 +++++++-------- 2 files changed, 12 insertions(+), 11 deletions(-) diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c index 4511420849bc..e84dbecd0991 100644 --- a/drivers/staging/android/ashmem.c +++ b/drivers/staging/android/ashmem.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -363,11 +364,12 @@ static int ashmem_shrink(struct shrinker *s, struct shrink_control *sc) mutex_lock(&ashmem_mutex); list_for_each_entry_safe(range, next, &ashmem_lru_list, lru) { - struct inode *inode = range->asma->file->f_dentry->d_inode; loff_t start = range->pgstart * PAGE_SIZE; - loff_t end = (range->pgend + 1) * PAGE_SIZE - 1; + loff_t end = (range->pgend + 1) * PAGE_SIZE; - vmtruncate_range(inode, start, end); + do_fallocate(range->asma->file, + FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, + start, end - start); range->purged = ASHMEM_WAS_PURGED; lru_del(range); diff --git a/mm/madvise.c b/mm/madvise.c index 1ccbba5b6674..deff1b64a08c 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -11,8 +11,10 @@ #include #include #include +#include #include #include +#include /* * Any behaviour which results in changes to the vma->vm_flags needs to @@ -200,8 +202,7 @@ static long madvise_remove(struct vm_area_struct *vma, struct vm_area_struct **prev, unsigned long start, unsigned long end) { - struct address_space *mapping; - loff_t offset, endoff; + loff_t offset; int error; *prev = NULL; /* tell sys_madvise we drop mmap_sem */ @@ -217,16 +218,14 @@ static long madvise_remove(struct vm_area_struct *vma, if ((vma->vm_flags & (VM_SHARED|VM_WRITE)) != (VM_SHARED|VM_WRITE)) return -EACCES; - mapping = vma->vm_file->f_mapping; - offset = (loff_t)(start - vma->vm_start) + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); - endoff = (loff_t)(end - vma->vm_start - 1) - + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); - /* vmtruncate_range needs to take i_mutex */ + /* filesystem's fallocate may need to take i_mutex */ up_read(¤t->mm->mmap_sem); - error = vmtruncate_range(mapping->host, offset, endoff); + error = do_fallocate(vma->vm_file, + FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, + offset, end - start); down_read(¤t->mm->mmap_sem); return error; } -- 2.30.2