7 files changed, 149 insertions, 89 deletions

diff --git a/fs/bio-integrity.c b/fs/bio-integrity.c
index 63e2ee63058d..c3e174b35fe6 100644
--- a/fs/bio-integrity.c
+++ b/fs/bio-integrity.c
@@ -705,7 +705,6 @@ void __init bio_integrity_init_slab(void)
         bio_integrity_slab = KMEM_CACHE(bio_integrity_payload,
                                         SLAB_HWCACHE_ALIGN|SLAB_PANIC);
 }
-EXPORT_SYMBOL(bio_integrity_init_slab);
 
 static int __init integrity_init(void)
 {
diff --git a/fs/buffer.c b/fs/buffer.c
index f95805019639..ca12a6bb82b1 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2096,6 +2096,52 @@ int generic_write_end(struct file *file, struct address_space *mapping,
 EXPORT_SYMBOL(generic_write_end);
 
 /*
+ * block_is_partially_uptodate checks whether buffers within a page are
+ * uptodate or not.
+ *
+ * Returns true if all buffers which correspond to a file portion
+ * we want to read are uptodate.
+ */
+int block_is_partially_uptodate(struct page *page, read_descriptor_t *desc,
+                                        unsigned long from)
+{
+        struct inode *inode = page->mapping->host;
+        unsigned block_start, block_end, blocksize;
+        unsigned to;
+        struct buffer_head *bh, *head;
+        int ret = 1;
+
+        if (!page_has_buffers(page))
+                return 0;
+
+        blocksize = 1 << inode->i_blkbits;
+        to = min_t(unsigned, PAGE_CACHE_SIZE - from, desc->count);
+        to = from + to;
+        if (from < blocksize && to > PAGE_CACHE_SIZE - blocksize)
+                return 0;
+
+        head = page_buffers(page);
+        bh = head;
+        block_start = 0;
+        do {
+                block_end = block_start + blocksize;
+                if (block_end > from && block_start < to) {
+                        if (!buffer_uptodate(bh)) {
+                                ret = 0;
+                                break;
+                        }
+                        if (block_end >= to)
+                                break;
+                }
+                block_start = block_end;
+                bh = bh->b_this_page;
+        } while (bh != head);
+
+        return ret;
+}
+EXPORT_SYMBOL(block_is_partially_uptodate);
+
+/*
  * Generic "read page" function for block devices that have the normal
  * get_block functionality. This is most of the block device filesystems.
  * Reads the page asynchronously --- the unlock_buffer() and
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index 7b99917ffadc..06db79d05c12 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -475,8 +475,8 @@ int ecryptfs_encrypt_page(struct page *page)
 {
         struct inode *ecryptfs_inode;
         struct ecryptfs_crypt_stat *crypt_stat;
-        char *enc_extent_virt = NULL;
-        struct page *enc_extent_page;
+        char *enc_extent_virt;
+        struct page *enc_extent_page = NULL;
         loff_t extent_offset;
         int rc = 0;
 
@@ -492,14 +492,14 @@ int ecryptfs_encrypt_page(struct page *page)
                                page->index);
                 goto out;
         }
-        enc_extent_virt = kmalloc(PAGE_CACHE_SIZE, GFP_USER);
-        if (!enc_extent_virt) {
+        enc_extent_page = alloc_page(GFP_USER);
+        if (!enc_extent_page) {
                 rc = -ENOMEM;
                 ecryptfs_printk(KERN_ERR, "Error allocating memory for "
                                 "encrypted extent\n");
                 goto out;
         }
-        enc_extent_page = virt_to_page(enc_extent_virt);
+        enc_extent_virt = kmap(enc_extent_page);
         for (extent_offset = 0;
              extent_offset < (PAGE_CACHE_SIZE / crypt_stat->extent_size);
              extent_offset++) {
@@ -527,7 +527,10 @@ int ecryptfs_encrypt_page(struct page *page)
                 }
         }
 out:
-        kfree(enc_extent_virt);
+        if (enc_extent_page) {
+                kunmap(enc_extent_page);
+                __free_page(enc_extent_page);
+        }
         return rc;
 }
 
@@ -609,8 +612,8 @@ int ecryptfs_decrypt_page(struct page *page)
 {
         struct inode *ecryptfs_inode;
         struct ecryptfs_crypt_stat *crypt_stat;
-        char *enc_extent_virt = NULL;
-        struct page *enc_extent_page;
+        char *enc_extent_virt;
+        struct page *enc_extent_page = NULL;
         unsigned long extent_offset;
         int rc = 0;
 
@@ -627,14 +630,14 @@ int ecryptfs_decrypt_page(struct page *page)
                                page->index);
                 goto out;
         }
-        enc_extent_virt = kmalloc(PAGE_CACHE_SIZE, GFP_USER);
-        if (!enc_extent_virt) {
+        enc_extent_page = alloc_page(GFP_USER);
+        if (!enc_extent_page) {
                 rc = -ENOMEM;
                 ecryptfs_printk(KERN_ERR, "Error allocating memory for "
                                 "encrypted extent\n");
                 goto out;
         }
-        enc_extent_page = virt_to_page(enc_extent_virt);
+        enc_extent_virt = kmap(enc_extent_page);
         for (extent_offset = 0;
              extent_offset < (PAGE_CACHE_SIZE / crypt_stat->extent_size);
              extent_offset++) {
@@ -662,7 +665,10 @@ int ecryptfs_decrypt_page(struct page *page)
                 }
         }
 out:
-        kfree(enc_extent_virt);
+        if (enc_extent_page) {
+                kunmap(enc_extent_page);
+                __free_page(enc_extent_page);
+        }
         return rc;
 }
 
diff --git a/fs/exec.c b/fs/exec.c
index 9696bbf0f0b1..32993beecbe9 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -32,6 +32,7 @@
 #include <linux/swap.h>
 #include <linux/string.h>
 #include <linux/init.h>
+#include <linux/pagemap.h>
 #include <linux/highmem.h>
 #include <linux/spinlock.h>
 #include <linux/key.h>
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 384fc0d1dd74..991d6dfeb51f 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -791,6 +791,7 @@ const struct address_space_operations ext2_aops = {
         .direct_IO              = ext2_direct_IO,
         .writepages             = ext2_writepages,
         .migratepage            = buffer_migrate_page,
+        .is_partially_uptodate  = block_is_partially_uptodate,
 };
 
 const struct address_space_operations ext2_aops_xip = {
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 3bf07d70b914..507d8689b111 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -1767,44 +1767,47 @@ static int ext3_journalled_set_page_dirty(struct page *page)
 }
 
 static const struct address_space_operations ext3_ordered_aops = {
-        .readpage       = ext3_readpage,
-        .readpages      = ext3_readpages,
-        .writepage      = ext3_ordered_writepage,
-        .sync_page      = block_sync_page,
-        .write_begin    = ext3_write_begin,
-        .write_end      = ext3_ordered_write_end,
-        .bmap           = ext3_bmap,
-        .invalidatepage = ext3_invalidatepage,
-        .releasepage    = ext3_releasepage,
-        .direct_IO      = ext3_direct_IO,
-        .migratepage    = buffer_migrate_page,
+        .readpage               = ext3_readpage,
+        .readpages              = ext3_readpages,
+        .writepage              = ext3_ordered_writepage,
+        .sync_page              = block_sync_page,
+        .write_begin            = ext3_write_begin,
+        .write_end              = ext3_ordered_write_end,
+        .bmap                   = ext3_bmap,
+        .invalidatepage         = ext3_invalidatepage,
+        .releasepage            = ext3_releasepage,
+        .direct_IO              = ext3_direct_IO,
+        .migratepage            = buffer_migrate_page,
+        .is_partially_uptodate  = block_is_partially_uptodate,
 };
 
 static const struct address_space_operations ext3_writeback_aops = {
-        .readpage       = ext3_readpage,
-        .readpages      = ext3_readpages,
-        .writepage      = ext3_writeback_writepage,
-        .sync_page      = block_sync_page,
-        .write_begin    = ext3_write_begin,
-        .write_end      = ext3_writeback_write_end,
-        .bmap           = ext3_bmap,
-        .invalidatepage = ext3_invalidatepage,
-        .releasepage    = ext3_releasepage,
-        .direct_IO      = ext3_direct_IO,
-        .migratepage    = buffer_migrate_page,
+        .readpage               = ext3_readpage,
+        .readpages              = ext3_readpages,
+        .writepage              = ext3_writeback_writepage,
+        .sync_page              = block_sync_page,
+        .write_begin            = ext3_write_begin,
+        .write_end              = ext3_writeback_write_end,
+        .bmap                   = ext3_bmap,
+        .invalidatepage         = ext3_invalidatepage,
+        .releasepage            = ext3_releasepage,
+        .direct_IO              = ext3_direct_IO,
+        .migratepage            = buffer_migrate_page,
+        .is_partially_uptodate  = block_is_partially_uptodate,
 };
 
 static const struct address_space_operations ext3_journalled_aops = {
-        .readpage       = ext3_readpage,
-        .readpages      = ext3_readpages,
-        .writepage      = ext3_journalled_writepage,
-        .sync_page      = block_sync_page,
-        .write_begin    = ext3_write_begin,
-        .write_end      = ext3_journalled_write_end,
-        .set_page_dirty = ext3_journalled_set_page_dirty,
-        .bmap           = ext3_bmap,
-        .invalidatepage = ext3_invalidatepage,
-        .releasepage    = ext3_releasepage,
+        .readpage               = ext3_readpage,
+        .readpages              = ext3_readpages,
+        .writepage              = ext3_journalled_writepage,
+        .sync_page              = block_sync_page,
+        .write_begin            = ext3_write_begin,
+        .write_end              = ext3_journalled_write_end,
+        .set_page_dirty         = ext3_journalled_set_page_dirty,
+        .bmap                   = ext3_bmap,
+        .invalidatepage         = ext3_invalidatepage,
+        .releasepage            = ext3_releasepage,
+        .is_partially_uptodate  = block_is_partially_uptodate,
 };
 
 void ext3_set_aops(struct inode *inode)
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 8ca2763df091..9843b046c235 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2806,59 +2806,63 @@ static int ext4_journalled_set_page_dirty(struct page *page)
 }
 
 static const struct address_space_operations ext4_ordered_aops = {
-        .readpage       = ext4_readpage,
-        .readpages      = ext4_readpages,
-        .writepage      = ext4_normal_writepage,
-        .sync_page      = block_sync_page,
-        .write_begin    = ext4_write_begin,
-        .write_end      = ext4_ordered_write_end,
-        .bmap           = ext4_bmap,
-        .invalidatepage = ext4_invalidatepage,
-        .releasepage    = ext4_releasepage,
-        .direct_IO      = ext4_direct_IO,
-        .migratepage    = buffer_migrate_page,
+        .readpage               = ext4_readpage,
+        .readpages              = ext4_readpages,
+        .writepage              = ext4_normal_writepage,
+        .sync_page              = block_sync_page,
+        .write_begin            = ext4_write_begin,
+        .write_end              = ext4_ordered_write_end,
+        .bmap                   = ext4_bmap,
+        .invalidatepage         = ext4_invalidatepage,
+        .releasepage            = ext4_releasepage,
+        .direct_IO              = ext4_direct_IO,
+        .migratepage            = buffer_migrate_page,
+        .is_partially_uptodate  = block_is_partially_uptodate,
 };
 
 static const struct address_space_operations ext4_writeback_aops = {
-        .readpage       = ext4_readpage,
-        .readpages      = ext4_readpages,
-        .writepage      = ext4_normal_writepage,
-        .sync_page      = block_sync_page,
-        .write_begin    = ext4_write_begin,
-        .write_end      = ext4_writeback_write_end,
-        .bmap           = ext4_bmap,
-        .invalidatepage = ext4_invalidatepage,
-        .releasepage    = ext4_releasepage,
-        .direct_IO      = ext4_direct_IO,
-        .migratepage    = buffer_migrate_page,
+        .readpage               = ext4_readpage,
+        .readpages              = ext4_readpages,
+        .writepage              = ext4_normal_writepage,
+        .sync_page              = block_sync_page,
+        .write_begin            = ext4_write_begin,
+        .write_end              = ext4_writeback_write_end,
+        .bmap                   = ext4_bmap,
+        .invalidatepage         = ext4_invalidatepage,
+        .releasepage            = ext4_releasepage,
+        .direct_IO              = ext4_direct_IO,
+        .migratepage            = buffer_migrate_page,
+        .is_partially_uptodate  = block_is_partially_uptodate,
 };
 
 static const struct address_space_operations ext4_journalled_aops = {
-        .readpage       = ext4_readpage,
-        .readpages      = ext4_readpages,
-        .writepage      = ext4_journalled_writepage,
-        .sync_page      = block_sync_page,
-        .write_begin    = ext4_write_begin,
-        .write_end      = ext4_journalled_write_end,
-        .set_page_dirty = ext4_journalled_set_page_dirty,
-        .bmap           = ext4_bmap,
-        .invalidatepage = ext4_invalidatepage,
-        .releasepage    = ext4_releasepage,
+        .readpage               = ext4_readpage,
+        .readpages              = ext4_readpages,
+        .writepage              = ext4_journalled_writepage,
+        .sync_page              = block_sync_page,
+        .write_begin            = ext4_write_begin,
+        .write_end              = ext4_journalled_write_end,
+        .set_page_dirty         = ext4_journalled_set_page_dirty,
+        .bmap                   = ext4_bmap,
+        .invalidatepage         = ext4_invalidatepage,
+        .releasepage            = ext4_releasepage,
+        .is_partially_uptodate  = block_is_partially_uptodate,
 };
 
 static const struct address_space_operations ext4_da_aops = {
-        .readpage       = ext4_readpage,
-        .readpages      = ext4_readpages,
-        .writepage      = ext4_da_writepage,
-        .writepages     = ext4_da_writepages,
-        .sync_page      = block_sync_page,
-        .write_begin    = ext4_da_write_begin,
-        .write_end      = ext4_da_write_end,
-        .bmap           = ext4_bmap,
-        .invalidatepage = ext4_da_invalidatepage,
-        .releasepage    = ext4_releasepage,
-        .direct_IO      = ext4_direct_IO,
-        .migratepage    = buffer_migrate_page,
+        .readpage               = ext4_readpage,
+        .readpages              = ext4_readpages,
+        .writepage              = ext4_da_writepage,
+        .writepages             = ext4_da_writepages,
+        .sync_page              = block_sync_page,
+        .write_begin            = ext4_da_write_begin,
+        .write_end              = ext4_da_write_end,
+        .bmap                   = ext4_bmap,
+        .invalidatepage         = ext4_da_invalidatepage,
+        .releasepage            = ext4_releasepage,
+        .direct_IO              = ext4_direct_IO,
+        .migratepage            = buffer_migrate_page,
+        .is_partially_uptodate  = block_is_partially_uptodate,
 };
 
 void ext4_set_aops(struct inode *inode)