1 files changed, 75 insertions, 34 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index 3464b681f844..7b84dc814347 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -75,8 +75,8 @@ generic_file_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
  *  ->mmap_sem
  *    ->lock_page               (access_process_vm)
  *
- *  ->mmap_sem
- *    ->i_mutex                 (msync)
+ *  ->i_mutex                   (generic_file_buffered_write)
+ *    ->mmap_sem                (fault_in_pages_readable->do_page_fault)
  *
  *  ->i_mutex
  *    ->i_alloc_sem             (various)
@@ -467,25 +467,15 @@ int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
 }
 
 #ifdef CONFIG_NUMA
-struct page *page_cache_alloc(struct address_space *x)
+struct page *__page_cache_alloc(gfp_t gfp)
 {
         if (cpuset_do_page_mem_spread()) {
                 int n = cpuset_mem_spread_node();
-                return alloc_pages_node(n, mapping_gfp_mask(x), 0);
+                return alloc_pages_node(n, gfp, 0);
         }
-        return alloc_pages(mapping_gfp_mask(x), 0);
+        return alloc_pages(gfp, 0);
 }
-EXPORT_SYMBOL(page_cache_alloc);
-
-struct page *page_cache_alloc_cold(struct address_space *x)
-{
-        if (cpuset_do_page_mem_spread()) {
-                int n = cpuset_mem_spread_node();
-                return alloc_pages_node(n, mapping_gfp_mask(x)|__GFP_COLD, 0);
-        }
-        return alloc_pages(mapping_gfp_mask(x)|__GFP_COLD, 0);
-}
-EXPORT_SYMBOL(page_cache_alloc_cold);
+EXPORT_SYMBOL(__page_cache_alloc);
 #endif
 
 static int __sleep_on_page_lock(void *word)
@@ -826,7 +816,6 @@ struct page *
 grab_cache_page_nowait(struct address_space *mapping, unsigned long index)
 {
         struct page *page = find_get_page(mapping, index);
-        gfp_t gfp_mask;
 
         if (page) {
                 if (!TestSetPageLocked(page))
@@ -834,9 +823,8 @@ grab_cache_page_nowait(struct address_space *mapping, unsigned long index)
                 page_cache_release(page);
                 return NULL;
         }
-        gfp_mask = mapping_gfp_mask(mapping) & ~__GFP_FS;
-        page = alloc_pages(gfp_mask, 0);
-        if (page && add_to_page_cache_lru(page, mapping, index, gfp_mask)) {
+        page = __page_cache_alloc(mapping_gfp_mask(mapping) & ~__GFP_FS);
+        if (page && add_to_page_cache_lru(page, mapping, index, GFP_KERNEL)) {
                 page_cache_release(page);
                 page = NULL;
         }
@@ -1884,11 +1872,10 @@ repeat:
  *      if suid or (sgid and xgrp)
  *              remove privs
  */
-int remove_suid(struct dentry *dentry)
+int should_remove_suid(struct dentry *dentry)
 {
         mode_t mode = dentry->d_inode->i_mode;
         int kill = 0;
-        int result = 0;
 
         /* suid always must be killed */
         if (unlikely(mode & S_ISUID))
@@ -1901,13 +1888,28 @@ int remove_suid(struct dentry *dentry)
         if (unlikely((mode & S_ISGID) && (mode & S_IXGRP)))
                 kill |= ATTR_KILL_SGID;
 
-        if (unlikely(kill && !capable(CAP_FSETID))) {
-                struct iattr newattrs;
+        if (unlikely(kill && !capable(CAP_FSETID)))
+                return kill;
 
-                newattrs.ia_valid = ATTR_FORCE | kill;
-                result = notify_change(dentry, &newattrs);
-        }
-        return result;
+        return 0;
+}
+
+int __remove_suid(struct dentry *dentry, int kill)
+{
+        struct iattr newattrs;
+
+        newattrs.ia_valid = ATTR_FORCE | kill;
+        return notify_change(dentry, &newattrs);
+}
+
+int remove_suid(struct dentry *dentry)
+{
+        int kill = should_remove_suid(dentry);
+
+        if (unlikely(kill))
+                return __remove_suid(dentry, kill);
+
+        return 0;
 }
 EXPORT_SYMBOL(remove_suid);
 
@@ -2222,7 +2224,7 @@ __generic_file_aio_write_nolock(struct kiocb *iocb, const struct iovec *iov,
                                 unsigned long nr_segs, loff_t *ppos)
 {
         struct file *file = iocb->ki_filp;
-        const struct address_space * mapping = file->f_mapping;
+        struct address_space * mapping = file->f_mapping;
         size_t ocount;          /* original count */
         size_t count;           /* after file limit checks */
         struct inode    *inode = mapping->host;
@@ -2275,8 +2277,11 @@ __generic_file_aio_write_nolock(struct kiocb *iocb, const struct iovec *iov,
 
         /* coalesce the iovecs and go direct-to-BIO for O_DIRECT */
         if (unlikely(file->f_flags & O_DIRECT)) {
-                written = generic_file_direct_write(iocb, iov,
-                                &nr_segs, pos, ppos, count, ocount);
+                loff_t endbyte;
+                ssize_t written_buffered;
+
+                written = generic_file_direct_write(iocb, iov, &nr_segs, pos,
+                                                        ppos, count, ocount);
                 if (written < 0 || written == count)
                         goto out;
                 /*
@@ -2285,10 +2290,46 @@ __generic_file_aio_write_nolock(struct kiocb *iocb, const struct iovec *iov,
                  */
                 pos += written;
                 count -= written;
-        }
+                written_buffered = generic_file_buffered_write(iocb, iov,
+                                                nr_segs, pos, ppos, count,
+                                                written);
+                /*
+                 * If generic_file_buffered_write() retuned a synchronous error
+                 * then we want to return the number of bytes which were
+                 * direct-written, or the error code if that was zero.  Note
+                 * that this differs from normal direct-io semantics, which
+                 * will return -EFOO even if some bytes were written.
+                 */
+                if (written_buffered < 0) {
+                        err = written_buffered;
+                        goto out;
+                }
 
-        written = generic_file_buffered_write(iocb, iov, nr_segs,
-                        pos, ppos, count, written);
+                /*
+                 * We need to ensure that the page cache pages are written to
+                 * disk and invalidated to preserve the expected O_DIRECT
+                 * semantics.
+                 */
+                endbyte = pos + written_buffered - written - 1;
+                err = do_sync_file_range(file, pos, endbyte,
+                                         SYNC_FILE_RANGE_WAIT_BEFORE|
+                                         SYNC_FILE_RANGE_WRITE|
+                                         SYNC_FILE_RANGE_WAIT_AFTER);
+                if (err == 0) {
+                        written = written_buffered;
+                        invalidate_mapping_pages(mapping,
+                                                 pos >> PAGE_CACHE_SHIFT,
+                                                 endbyte >> PAGE_CACHE_SHIFT);
+                } else {
+                        /*
+                         * We don't know how much we wrote, so just return
+                         * the number of bytes which were direct-written
+                         */
+                }
+        } else {
+                written = generic_file_buffered_write(iocb, iov, nr_segs,
+                                pos, ppos, count, written);
+        }
 out:
         current->backing_dev_info = NULL;
         return written ? written : err;