ceph: factor out libceph from Ceph file system

This factors out protocol and low-level storage parts of ceph into a
separate libceph module living in net/ceph and include/linux/ceph.  This
is mostly a matter of moving files around.  However, a few key pieces
of the interface change as well:

 - ceph_client becomes ceph_fs_client and ceph_client, where the latter
   captures the mon and osd clients, and the fs_client gets the mds client
   and file system specific pieces.
 - Mount option parsing and debugfs setup is correspondingly broken into
   two pieces.
 - The mon client gets a generic handler callback for otherwise unknown
   messages (mds map, in this case).
 - The basic supported/required feature bits can be expanded (and are by
   ceph_fs_client).

No functional change, aside from some subtle error handling cases that got
cleaned up in the refactoring process.

Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 68 insertions, 0 deletions

diff --git a/net/ceph/buffer.c b/net/ceph/buffer.c
new file mode 100644
index 000000000000..53d8abfa25d5
--- /dev/null
+++ b/net/ceph/buffer.c
@@ -0,0 +1,68 @@
+
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include <linux/ceph/buffer.h>
+#include <linux/ceph/decode.h>
+
+struct ceph_buffer *ceph_buffer_new(size_t len, gfp_t gfp)
+{
+        struct ceph_buffer *b;
+
+        b = kmalloc(sizeof(*b), gfp);
+        if (!b)
+                return NULL;
+
+        b->vec.iov_base = kmalloc(len, gfp | __GFP_NOWARN);
+        if (b->vec.iov_base) {
+                b->is_vmalloc = false;
+        } else {
+                b->vec.iov_base = __vmalloc(len, gfp, PAGE_KERNEL);
+                if (!b->vec.iov_base) {
+                        kfree(b);
+                        return NULL;
+                }
+                b->is_vmalloc = true;
+        }
+
+        kref_init(&b->kref);
+        b->alloc_len = len;
+        b->vec.iov_len = len;
+        dout("buffer_new %p\n", b);
+        return b;
+}
+EXPORT_SYMBOL(ceph_buffer_new);
+
+void ceph_buffer_release(struct kref *kref)
+{
+        struct ceph_buffer *b = container_of(kref, struct ceph_buffer, kref);
+
+        dout("buffer_release %p\n", b);
+        if (b->vec.iov_base) {
+                if (b->is_vmalloc)
+                        vfree(b->vec.iov_base);
+                else
+                        kfree(b->vec.iov_base);
+        }
+        kfree(b);
+}
+EXPORT_SYMBOL(ceph_buffer_release);
+
+int ceph_decode_buffer(struct ceph_buffer **b, void **p, void *end)
+{
+        size_t len;
+
+        ceph_decode_need(p, end, sizeof(u32), bad);
+        len = ceph_decode_32(p);
+        dout("decode_buffer len %d\n", (int)len);
+        ceph_decode_need(p, end, len, bad);
+        *b = ceph_buffer_new(len, GFP_NOFS);
+        if (!*b)
+                return -ENOMEM;
+        ceph_decode_copy(p, (*b)->vec.iov_base, len);
+        return 0;
+bad:
+        return -EINVAL;
+}