These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / fs / cachefiles / rdwr.c

diff --git a/kernel/fs/cachefiles/rdwr.c b/kernel/fs/cachefiles/rdwr.c
index 3cbb0e8..c0f3da3 100644 (file)
--- a/kernel/fs/cachefiles/rdwr.c
+++ b/kernel/fs/cachefiles/rdwr.c
@@ -414,9 +414,6 @@ int cachefiles_read_or_alloc_page(struct fscache_retrieval *op,
        ASSERT(inode->i_mapping->a_ops->readpages);
 
        /* calculate the shift required to use bmap */
-       if (inode->i_sb->s_blocksize > PAGE_SIZE)
-               goto enobufs;
-
        shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits;
 
        op->op.flags &= FSCACHE_OP_KEEP_FLAGS;
@@ -711,9 +708,6 @@ int cachefiles_read_or_alloc_pages(struct fscache_retrieval *op,
        ASSERT(inode->i_mapping->a_ops->readpages);
 
        /* calculate the shift required to use bmap */
-       if (inode->i_sb->s_blocksize > PAGE_SIZE)
-               goto all_enobufs;
-
        shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits;
 
        pagevec_init(&pagevec, 0);
@@ -885,7 +879,7 @@ int cachefiles_write_page(struct fscache_storage *op, struct page *page)
        loff_t pos, eof;
        size_t len;
        void *data;
-       int ret;
+       int ret = -ENOBUFS;
 
        ASSERT(op != NULL);
        ASSERT(page != NULL);
@@ -905,6 +899,15 @@ int cachefiles_write_page(struct fscache_storage *op, struct page *page)
        cache = container_of(object->fscache.cache,
                             struct cachefiles_cache, cache);
 
+       pos = (loff_t)page->index << PAGE_SHIFT;
+
+       /* We mustn't write more data than we have, so we have to beware of a
+        * partial page at EOF.
+        */
+       eof = object->fscache.store_limit_l;
+       if (pos >= eof)
+               goto error;
+
        /* write the page to the backing filesystem and let it store it in its
         * own time */
        path.mnt = cache->mnt;
@@ -912,40 +915,38 @@ int cachefiles_write_page(struct fscache_storage *op, struct page *page)
        file = dentry_open(&path, O_RDWR | O_LARGEFILE, cache->cache_cred);
        if (IS_ERR(file)) {
                ret = PTR_ERR(file);
-       } else {
-               pos = (loff_t) page->index << PAGE_SHIFT;
-
-               /* we mustn't write more data than we have, so we have
-                * to beware of a partial page at EOF */
-               eof = object->fscache.store_limit_l;
-               len = PAGE_SIZE;
-               if (eof & ~PAGE_MASK) {
-                       ASSERTCMP(pos, <, eof);
-                       if (eof - pos < PAGE_SIZE) {
-                               _debug("cut short %llx to %llx",
-                                      pos, eof);
-                               len = eof - pos;
-                               ASSERTCMP(pos + len, ==, eof);
-                       }
-               }
-
-               data = kmap(page);
-               ret = __kernel_write(file, data, len, &pos);
-               kunmap(page);
-               if (ret != len)
-                       ret = -EIO;
-               fput(file);
+               goto error_2;
        }
 
-       if (ret < 0) {
-               if (ret == -EIO)
-                       cachefiles_io_error_obj(
-                               object, "Write page to backing file failed");
-               ret = -ENOBUFS;
+       len = PAGE_SIZE;
+       if (eof & ~PAGE_MASK) {
+               if (eof - pos < PAGE_SIZE) {
+                       _debug("cut short %llx to %llx",
+                              pos, eof);
+                       len = eof - pos;
+                       ASSERTCMP(pos + len, ==, eof);
+               }
        }
 
-       _leave(" = %d", ret);
-       return ret;
+       data = kmap(page);
+       ret = __kernel_write(file, data, len, &pos);
+       kunmap(page);
+       fput(file);
+       if (ret != len)
+               goto error_eio;
+
+       _leave(" = 0");
+       return 0;
+
+error_eio:
+       ret = -EIO;
+error_2:
+       if (ret == -EIO)
+               cachefiles_io_error_obj(object,
+                                       "Write page to backing file failed");
+error:
+       _leave(" = -ENOBUFS [%d]", ret);
+       return -ENOBUFS;
 }
 
 /*