diff --git a/include/asm-alpha/mman.h b/include/asm-alpha/mman.h
index eb9c279045efe07573e308c5715eb7458c4e91df..f6439532a262d45e2ff47655edfd87cb9fcf55fb 100644
--- a/include/asm-alpha/mman.h
+++ b/include/asm-alpha/mman.h
@@ -42,6 +42,7 @@
#define MADV_WILLNEED 3 /* will need these pages */
#define MADV_SPACEAVAIL 5 /* ensure resources are available */
#define MADV_DONTNEED 6 /* don't need these pages */
+#define MADV_REMOVE 7 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-arm/mman.h b/include/asm-arm/mman.h
index 8e4f69c4fa5faa845479b68e4e3159374576f5f1..f0bebca2ac214a5b6b87dc8413c18b3cd9115ceb 100644
--- a/include/asm-arm/mman.h
+++ b/include/asm-arm/mman.h
@@ -35,6 +35,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-arm26/mman.h b/include/asm-arm26/mman.h
index cc27b824026564af2b61d9373923b9d6bebbd709..0ed7780541fa1b27abba46b8541bcb6cf583d1c6 100644
--- a/include/asm-arm26/mman.h
+++ b/include/asm-arm26/mman.h
@@ -35,6 +35,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-cris/mman.h b/include/asm-cris/mman.h
index 8570e72b9502cd73d560785ba9acdb9b8525db4f..5a382b8bf3f738effedd851b6887f7ce4197817b 100644
--- a/include/asm-cris/mman.h
+++ b/include/asm-cris/mman.h
@@ -37,6 +37,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-frv/mman.h b/include/asm-frv/mman.h
index c684720dfbdd15fd5c312243e7a0ecc95c374b76..8af4a41c255e113b6bf38b37fb0eafb26e312f65 100644
--- a/include/asm-frv/mman.h
+++ b/include/asm-frv/mman.h
@@ -35,6 +35,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-h8300/mman.h b/include/asm-h8300/mman.h
index 63f727a59850bfa64f3723d30d2dc7a324553ed6..744a8fb485c230780ff6256abc483a58bab647b2 100644
--- a/include/asm-h8300/mman.h
+++ b/include/asm-h8300/mman.h
@@ -35,6 +35,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-i386/mman.h b/include/asm-i386/mman.h
index 196619a838543e044f9e81088e63d28ebf899ace..ba4941e6f643213f39bcff3379259cdadf8584d3 100644
--- a/include/asm-i386/mman.h
+++ b/include/asm-i386/mman.h
@@ -35,6 +35,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-ia64/mman.h b/include/asm-ia64/mman.h
index 1c0a73af1461363a225eb0af75ecb7c5ba012694..828beb24a20ec7837fe7a00dde7c4b8b93bbe941 100644
--- a/include/asm-ia64/mman.h
+++ b/include/asm-ia64/mman.h
@@ -43,6 +43,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-m32r/mman.h b/include/asm-m32r/mman.h
index 011f6d9ec5cc79c5271e2e7c7791decfa8e626a7..12e29747bc84a510163f6e948f3d6834047e0c7c 100644
--- a/include/asm-m32r/mman.h
+++ b/include/asm-m32r/mman.h
@@ -37,6 +37,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-m68k/mman.h b/include/asm-m68k/mman.h
index f831c4eeae6e0fd05c0cdd3552615cad83a1736c..ea262ab88b3bb547761227d0a039e7800674bc4c 100644
--- a/include/asm-m68k/mman.h
+++ b/include/asm-m68k/mman.h
@@ -35,6 +35,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-mips/mman.h b/include/asm-mips/mman.h
index 62060957ba93a743d8b8ceaa11b11f2706ffb578..dd17c8bd62a1cbc4450db3b21035f8de94826639 100644
--- a/include/asm-mips/mman.h
+++ b/include/asm-mips/mman.h
@@ -65,6 +65,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-parisc/mman.h b/include/asm-parisc/mman.h
index e829607eb8bc2a4d2e77c48bc93362cc311ddeee..736b0abcac052b1ad468ff0362bfe8e3173c531a 100644
--- a/include/asm-parisc/mman.h
+++ b/include/asm-parisc/mman.h
@@ -38,6 +38,7 @@
#define MADV_SPACEAVAIL 5 /* insure that resources are reserved */
#define MADV_VPS_PURGE 6 /* Purge pages from VM page cache */
#define MADV_VPS_INHERIT 7 /* Inherit parents page size */
+#define MADV_REMOVE 8 /* remove these pages & resources */
/* The range 12-64 is reserved for page size specification. */
#define MADV_4K_PAGES 12 /* Use 4K pages */
diff --git a/include/asm-powerpc/mman.h b/include/asm-powerpc/mman.h
index f5e5342fcac52f94761089e9b4c12f0aebb23b96..a2e34c21b44f8f09455dad99aef78285d166da1a 100644
--- a/include/asm-powerpc/mman.h
+++ b/include/asm-powerpc/mman.h
@@ -44,6 +44,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-s390/mman.h b/include/asm-s390/mman.h
index ea86bd12204fe55032fe1418ed62924b606bda29..c8d5409b5d563c383e9fa4f8378504b41c992473 100644
--- a/include/asm-s390/mman.h
+++ b/include/asm-s390/mman.h
@@ -43,6 +43,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-sh/mman.h b/include/asm-sh/mman.h
index 3ebab5f79db794d34afa60a62ce8ec9a462a49c4..693bd55a37104f543a2c5e3a21878bbc5cd3d395 100644
--- a/include/asm-sh/mman.h
+++ b/include/asm-sh/mman.h
@@ -35,6 +35,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-sparc/mman.h b/include/asm-sparc/mman.h
index 138eb81dd70d3fd5a1c0a9f2b1e266049e960d47..98435ad8619e0b0b5f5cd9aa882de51d6ea89948 100644
--- a/include/asm-sparc/mman.h
+++ b/include/asm-sparc/mman.h
@@ -54,6 +54,7 @@
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
#define MADV_FREE 0x5 /* (Solaris) contents can be freed */
+#define MADV_REMOVE 0x6 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-sparc64/mman.h b/include/asm-sparc64/mman.h
index 01cecf54357b876d3fe5d8f31c33ac181a8bb670..cb4b6156194dbe12dc92adfba8c3247400ebd0f8 100644
--- a/include/asm-sparc64/mman.h
+++ b/include/asm-sparc64/mman.h
@@ -54,6 +54,7 @@
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
#define MADV_FREE 0x5 /* (Solaris) contents can be freed */
+#define MADV_REMOVE 0x6 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-v850/mman.h b/include/asm-v850/mman.h
index e2b90081b56f8ca2d7b3f9dc6a6012b249ee9add..edc79965193aa589e6810b35903fb7262c404927 100644
--- a/include/asm-v850/mman.h
+++ b/include/asm-v850/mman.h
@@ -32,6 +32,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-x86_64/mman.h b/include/asm-x86_64/mman.h
index 78e60a4fd4ee543c58ba359f9488bddcc95741f4..d0e97b74f73591d0e430719f0861dc00dda1d224 100644
--- a/include/asm-x86_64/mman.h
+++ b/include/asm-x86_64/mman.h
@@ -36,6 +36,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/asm-xtensa/mman.h b/include/asm-xtensa/mman.h
index 9a95a45df99634f08ef0d84fd9a8ed808ab0975b..082a7504925ed5bebeda7b910b25de6bc58075c1 100644
--- a/include/asm-xtensa/mman.h
+++ b/include/asm-xtensa/mman.h
@@ -72,6 +72,7 @@
#define MADV_SEQUENTIAL 0x2 /* read-ahead aggressively */
#define MADV_WILLNEED 0x3 /* pre-fault pages */
#define MADV_DONTNEED 0x4 /* discard these pages */
+#define MADV_REMOVE 0x5 /* remove these pages & resources */
/* compatibility flags */
#define MAP_ANON MAP_ANONYMOUS
diff --git a/include/linux/fs.h b/include/linux/fs.h
index ed9a41a71e8b57ff62ea245fbbe46e586d74c5ee..115e72be25d0cd7b7a7436e4d82f389b7cbf7c8f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1050,6 +1050,7 @@ struct inode_operations {
ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
ssize_t (*listxattr) (struct dentry *, char *, size_t);
int (*removexattr) (struct dentry *, const char *);
+ void (*truncate_range)(struct inode *, loff_t, loff_t);
};
struct seq_file;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 92acae9f1f4cb14bf543e277b7228e5fec369a02..6c9be99429f31639e4a0b1809bbd6f758299202b 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -690,6 +690,7 @@ static inline void unmap_shared_mapping_range(struct address_space *mapping,
}
extern int vmtruncate(struct inode * inode, loff_t offset);
+extern int vmtruncate_range(struct inode * inode, loff_t offset, loff_t end);
extern int install_page(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, struct page *page, pgprot_t prot);
extern int install_file_pte(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, unsigned long pgoff, pgprot_t prot);
extern int __handle_mm_fault(struct mm_struct *mm,struct vm_area_struct *vma, unsigned long address, int write_access);
diff --git a/mm/madvise.c b/mm/madvise.c
index 2b7cf0400a217cd453641eaf097d1291125e1431..ae0ae3ea299a7a83b72939236ef4931eb5ac16d0 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -140,6 +140,36 @@ static long madvise_dontneed(struct vm_area_struct * vma,
return 0;
}
+/*
+ * Application wants to free up the pages and associated backing store.
+ * This is effectively punching a hole into the middle of a file.
+ *
+ * NOTE: Currently, only shmfs/tmpfs is supported for this operation.
+ * Other filesystems return -ENOSYS.
+ */
+static long madvise_remove(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end)
+{
+ struct address_space *mapping;
+ loff_t offset, endoff;
+
+ if (vma->vm_flags & (VM_LOCKED|VM_NONLINEAR|VM_HUGETLB))
+ return -EINVAL;
+
+ if (!vma->vm_file || !vma->vm_file->f_mapping
+ || !vma->vm_file->f_mapping->host) {
+ return -EINVAL;
+ }
+
+ 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);
+ return vmtruncate_range(mapping->host, offset, endoff);
+}
+
static long
madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
unsigned long start, unsigned long end, int behavior)
@@ -152,6 +182,9 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
case MADV_RANDOM:
error = madvise_behavior(vma, prev, start, end, behavior);
break;
+ case MADV_REMOVE:
+ error = madvise_remove(vma, start, end);
+ break;
case MADV_WILLNEED:
error = madvise_willneed(vma, prev, start, end);
@@ -190,6 +223,8 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
* some pages ahead.
* MADV_DONTNEED - the application is finished with the given range,
* so the kernel can free resources associated with it.
+ * MADV_REMOVE - the application wants to free up the given range of
+ * pages and associated backing store.
*
* return values:
* zero - success
diff --git a/mm/memory.c b/mm/memory.c
index d8dde07a36566fc6463b7b9b95305d9b0505427e..e249088908c436940386cbf161f1b6d0c7c39c0b 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1770,9 +1770,32 @@ int vmtruncate(struct inode * inode, loff_t offset)
out_busy:
return -ETXTBSY;
}
-
EXPORT_SYMBOL(vmtruncate);
+int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end)
+{
+ struct address_space *mapping = inode->i_mapping;
+
+ /*
+ * If the underlying filesystem is not going to provide
+ * a way to truncate a range of blocks (punch a hole) -
+ * we should return failure right now.
+ */
+ if (!inode->i_op || !inode->i_op->truncate_range)
+ return -ENOSYS;
+
+ down(&inode->i_sem);
+ down_write(&inode->i_alloc_sem);
+ unmap_mapping_range(mapping, offset, (end - offset), 1);
+ truncate_inode_pages_range(mapping, offset, end);
+ inode->i_op->truncate_range(inode, offset, end);
+ up_write(&inode->i_alloc_sem);
+ up(&inode->i_sem);
+
+ return 0;
+}
+EXPORT_SYMBOL(vmtruncate_range);
+
/*
* Primitive swap readahead code. We simply read an aligned block of
* (1 << page_cluster) entries in the swap area. This method is chosen
diff --git a/mm/shmem.c b/mm/shmem.c
index d9fc277940da5473e472087c115f5be10608c190..65c148efa2ed90f2f1921b2b9a7ddde5bde8d035 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -457,7 +457,7 @@ static void shmem_free_pages(struct list_head *next)
} while (next);
}
-static void shmem_truncate(struct inode *inode)
+static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end)
{
struct shmem_inode_info *info = SHMEM_I(inode);
unsigned long idx;
@@ -475,18 +475,27 @@ static void shmem_truncate(struct inode *inode)
long nr_swaps_freed = 0;
int offset;
int freed;
+ int punch_hole = 0;
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
- idx = (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+ idx = (start + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
if (idx >= info->next_index)
return;
spin_lock(&info->lock);
info->flags |= SHMEM_TRUNCATE;
- limit = info->next_index;
- info->next_index = idx;
+ if (likely(end == (loff_t) -1)) {
+ limit = info->next_index;
+ info->next_index = idx;
+ } else {
+ limit = (end + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+ if (limit > info->next_index)
+ limit = info->next_index;
+ punch_hole = 1;
+ }
+
topdir = info->i_indirect;
- if (topdir && idx <= SHMEM_NR_DIRECT) {
+ if (topdir && idx <= SHMEM_NR_DIRECT && !punch_hole) {
info->i_indirect = NULL;
nr_pages_to_free++;
list_add(&topdir->lru, &pages_to_free);
@@ -573,11 +582,12 @@ static void shmem_truncate(struct inode *inode)
set_page_private(subdir, page_private(subdir) - freed);
if (offset)
spin_unlock(&info->lock);
- BUG_ON(page_private(subdir) > offset);
+ if (!punch_hole)
+ BUG_ON(page_private(subdir) > offset);
}
if (offset)
offset = 0;
- else if (subdir) {
+ else if (subdir && !page_private(subdir)) {
dir[diroff] = NULL;
nr_pages_to_free++;
list_add(&subdir->lru, &pages_to_free);
@@ -594,7 +604,7 @@ static void shmem_truncate(struct inode *inode)
* Also, though shmem_getpage checks i_size before adding to
* cache, no recheck after: so fix the narrow window there too.
*/
- truncate_inode_pages(inode->i_mapping, inode->i_size);
+ truncate_inode_pages_range(inode->i_mapping, start, end);
}
spin_lock(&info->lock);
@@ -614,6 +624,11 @@ static void shmem_truncate(struct inode *inode)
}
}
+static void shmem_truncate(struct inode *inode)
+{
+ shmem_truncate_range(inode, inode->i_size, (loff_t)-1);
+}
+
static int shmem_notify_change(struct dentry *dentry, struct iattr *attr)
{
struct inode *inode = dentry->d_inode;
@@ -2083,6 +2098,7 @@ static struct file_operations shmem_file_operations = {
static struct inode_operations shmem_inode_operations = {
.truncate = shmem_truncate,
.setattr = shmem_notify_change,
+ .truncate_range = shmem_truncate_range,
};
static struct inode_operations shmem_dir_inode_operations = {