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From:   Daniel Xu <dxu@dxuuu.xyz>
To:     cgroups@vger.kernel.org, tj@kernel.org, lizefan@huawei.com,
        hannes@cmpxchg.org, viro@zeniv.linux.org.uk
Cc:     Daniel Xu <dxu@dxuuu.xyz>, shakeelb@google.com,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        gregkh@linuxfoundation.org, kernel-team@fb.com
Subject: [PATCH v3 1/4] kernfs: kvmalloc xattr value instead of kmalloc
Date:   Thu, 12 Mar 2020 13:03:14 -0700
Message-Id: <20200312200317.31736-2-dxu@dxuuu.xyz>
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xattr values have a 64k maximum size. This can result in an order 4
kmalloc request which can be difficult to fulfill. Since xattrs do not
need physically contiguous memory, we can switch to kvmalloc and not
have to worry about higher order allocations failing.

Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
---
 fs/xattr.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/xattr.c b/fs/xattr.c
index 90dd78f0eb27..0d3c9b4d1914 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -817,7 +817,7 @@ struct simple_xattr *simple_xattr_alloc(const void *value, size_t size)
 	if (len < sizeof(*new_xattr))
 		return NULL;
 
-	new_xattr = kmalloc(len, GFP_KERNEL);
+	new_xattr = kvmalloc(len, GFP_KERNEL);
 	if (!new_xattr)
 		return NULL;
 
@@ -882,7 +882,7 @@ int simple_xattr_set(struct simple_xattrs *xattrs, const char *name,
 
 		new_xattr->name = kstrdup(name, GFP_KERNEL);
 		if (!new_xattr->name) {
-			kfree(new_xattr);
+			kvfree(new_xattr);
 			return -ENOMEM;
 		}
 	}
@@ -912,7 +912,7 @@ int simple_xattr_set(struct simple_xattrs *xattrs, const char *name,
 	spin_unlock(&xattrs->lock);
 	if (xattr) {
 		kfree(xattr->name);
-		kfree(xattr);
+		kvfree(xattr);
 	}
 	return err;
 
-- 
2.21.1