[Sheepdog] [PATCH v2 07/15] sheepfs: add 'volume' entry
Liu Yuan
namei.unix at gmail.com
Mon May 14 11:47:32 CEST 2012
From: Liu Yuan <tailai.ly at taobao.com>
This is where we can access sheepdog's storage from well received 'file'
abstraction. All the attatched volume will be seen as a file in volume
directory.
To attatch a volume:
echo test > sheepfs_dir/vdi/mount
Then you will see a file entry in sheepfs_dir/volume/test, which you can do
the tricks you are fond of. For, e.g, we can boot an sheepdog image as normally
as for an ordinary raw image:
$ qemu-system-x86_64 --enable-kvm -m 1024 -drive \
file=sheepfs_dir/volume/test,cache=writeback.
This file abstraction integrates well with kernel's other component such as
pagecache.
Signed-off-by: Liu Yuan <tailai.ly at taobao.com>
---
sheepfs/Makefile.am | 2 +-
sheepfs/core.c | 8 +-
sheepfs/sheepfs.h | 8 ++
sheepfs/volume.c | 299 +++++++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 314 insertions(+), 3 deletions(-)
create mode 100644 sheepfs/volume.c
diff --git a/sheepfs/Makefile.am b/sheepfs/Makefile.am
index f6201a6..c451b86 100644
--- a/sheepfs/Makefile.am
+++ b/sheepfs/Makefile.am
@@ -23,7 +23,7 @@ INCLUDES = -I$(top_builddir)/include -I$(top_srcdir)/include
sbin_PROGRAMS = sheepfs
-sheepfs_SOURCES = core.c cluster.c vdi.c shadow_file.c
+sheepfs_SOURCES = core.c cluster.c vdi.c shadow_file.c volume.c
sheepfs_LDADD = ../lib/libsheepdog.a $(fuse_LIBS) $(LIBS)
sheepfs_DEPENDENCIES = ../lib/libsheepdog.a
diff --git a/sheepfs/core.c b/sheepfs/core.c
index c042245..0f4f451 100644
--- a/sheepfs/core.c
+++ b/sheepfs/core.c
@@ -48,10 +48,10 @@ static struct sheepfs_file_operation {
size_t (*get_size)(const char *path);
} sheepfs_file_ops[] = {
[OP_NULL ] = { NULL, NULL, NULL },
- [OP_CLUSTER_INFO] = { cluster_info_read, NULL,
- cluster_info_get_size },
+ [OP_CLUSTER_INFO] = { cluster_info_read, NULL, cluster_info_get_size },
[OP_VDI_LIST] = { vdi_list_read, NULL, vdi_list_get_size },
[OP_VDI_MOUNT] = { NULL, vdi_mount_write, NULL },
+ [OP_VOLUME] = { volume_read, volume_write, volume_get_size },
};
int sheepfs_set_op(const char *path, unsigned opcode)
@@ -184,6 +184,8 @@ static int sheepfs_main_loop(char *mountpoint)
int ret = -1;
fuse_opt_add_arg(&args, "sheepfs"); /* placeholder for argv[0] */
+ fuse_opt_add_arg(&args, "-oallow_root");
+ fuse_opt_add_arg(&args, "-obig_writes");
fuse_opt_add_arg(&args, "-ofsname=sheepfs");
fuse_opt_add_arg(&args, mountpoint);
if (sheepfs_debug)
@@ -204,6 +206,8 @@ static int create_sheepfs_layout(void)
return -1;
if (create_vdi_layout() < 0)
return -1;
+ if (create_volume_layout() < 0)
+ return -1;
return 0;
}
diff --git a/sheepfs/sheepfs.h b/sheepfs/sheepfs.h
index 48f3dbc..cfb1402 100644
--- a/sheepfs/sheepfs.h
+++ b/sheepfs/sheepfs.h
@@ -6,6 +6,7 @@ enum sheepfs_opcode {
OP_CLUSTER_INFO,
OP_VDI_LIST,
OP_VDI_MOUNT,
+ OP_VOLUME,
};
extern char sheepfs_shadow[];
@@ -25,6 +26,13 @@ extern int shadow_file_getxattr(const char *path, const char *name,
extern int shadow_file_delete(const char *path);
extern int shadow_file_exsit(const char *path);
+/* volume.c */
+extern int create_volume_layout(void);
+extern int volume_read(const char *path, char *buf, size_t size, off_t offset);
+extern int volume_write(const char *, const char *buf, size_t size, off_t);
+extern size_t volume_get_size(const char *);
+extern int volume_create_entry(const char *entry);
+
/* cluster.c */
extern int cluster_info_read(const char *path, char *buf, size_t size, off_t);
extern size_t cluster_info_get_size(const char *path);
diff --git a/sheepfs/volume.c b/sheepfs/volume.c
new file mode 100644
index 0000000..438e9a2
--- /dev/null
+++ b/sheepfs/volume.c
@@ -0,0 +1,299 @@
+/*
+ * Copyright (C) 2012 Taobao Inc.
+ *
+ * Liu Yuan <namei.unix at gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <time.h>
+#include <assert.h>
+#include <syslog.h>
+
+#include "strbuf.h"
+#include "sheepfs.h"
+#include "net.h"
+#include "rbtree.h"
+
+#define PATH_VOLUME "/volume"
+
+#define SH_VID_NAME "user.volume.vid"
+#define SH_VID_SIZE sizeof(uint32_t)
+
+#define SH_SIZE_NAME "user.volume.size"
+#define SH_SIZE_SIZE sizeof(size_t)
+
+#define VOLUME_READ 0
+#define VOLUME_WRITE 1
+
+struct vdi_inode {
+ struct rb_node rb;
+ uint32_t vid;
+ struct sheepdog_inode *inode;
+};
+
+static struct rb_root vdi_inode_tree = RB_ROOT;
+
+static struct vdi_inode *vdi_inode_tree_insert(struct vdi_inode *new)
+{
+ struct rb_node **p = &vdi_inode_tree.rb_node;
+ struct rb_node *parent = NULL;
+ struct vdi_inode *entry;
+
+ while (*p) {
+ parent = *p;
+ entry = rb_entry(parent, struct vdi_inode, rb);
+
+ if (new->vid < entry->vid)
+ p = &(*p)->rb_left;
+ else if (new->vid > entry->vid)
+ p = &(*p)->rb_right;
+ else
+ return entry; /* already has this entry */
+ }
+ rb_link_node(&new->rb, parent, p);
+ rb_insert_color(&new->rb, &vdi_inode_tree);
+
+ return NULL; /* insert successfully */
+}
+
+static struct vdi_inode *vdi_inode_tree_search(uint32_t vid)
+{
+ struct rb_node *n = vdi_inode_tree.rb_node;
+ struct vdi_inode *t;
+
+ while (n) {
+ t = rb_entry(n, struct vdi_inode, rb);
+
+ if (vid < t->vid)
+ n = n->rb_left;
+ else if (vid > t->vid)
+ n = n->rb_right;
+ else
+ return t; /* found it */
+ }
+
+ return NULL;
+}
+
+int create_volume_layout(void)
+{
+ if (shadow_dir_create(PATH_VOLUME) < 0)
+ return -1;
+ return 0;
+}
+
+static int volume_rw_object(char *buf, uint64_t oid, size_t size,
+ off_t off, int rw)
+{
+ struct sd_obj_req hdr = { 0 };
+ struct sd_obj_rsp *rsp = (struct sd_obj_rsp *)&hdr;
+ int ret;
+ unsigned wlen = 0, rlen = 0;
+ int create = 0;
+ uint32_t vid = oid_to_vid(oid);
+ struct vdi_inode *vdi = vdi_inode_tree_search(vid);
+ unsigned long idx = 0;
+
+ if (is_data_obj(oid)) {
+ idx = data_oid_to_idx(oid);
+ assert(vdi);
+ if (!vdi->inode->data_vdi_id[idx]) {
+ /* if object doesn't exist, we'er done */
+ if (rw == VOLUME_READ) {
+ memset(buf, 0, size);
+ goto done;
+ }
+ create = 1;
+ }
+ }
+
+ if (rw == VOLUME_READ) {
+ rlen = size;
+ hdr.opcode = SD_OP_READ_OBJ;
+ } else {
+ wlen = size;
+ hdr.opcode = create ?
+ SD_OP_CREATE_AND_WRITE_OBJ : SD_OP_WRITE_OBJ;
+ hdr.flags |= SD_FLAG_CMD_WRITE;
+ }
+
+ hdr.oid = oid;
+ hdr.data_length = size;
+ hdr.offset = off;
+ hdr.flags |= SD_FLAG_CMD_CACHE;
+
+ ret = exec_req(0, (struct sd_req *)&hdr, buf, &wlen, &rlen);
+
+ if (ret || rsp->result != SD_RES_SUCCESS) {
+ syslog(LOG_ERR, "failed to %s object %" PRIx64 " ret %d, res %d\n",
+ rw == VOLUME_READ ? "read" : "write", oid, ret,
+ rsp->result);
+ return -1;
+ }
+
+ if (create) {
+ vdi->inode->data_vdi_id[idx] = vid;
+ /* writeback inode update */
+ if (volume_rw_object((char *)&vid, vid_to_vdi_oid(vid),
+ sizeof(vid),
+ SD_INODE_HEADER_SIZE + sizeof(vid) * idx,
+ VOLUME_WRITE) < 0)
+ return -1;
+ }
+done:
+ return size;
+}
+
+/* Do sync read/write */
+static int volume_do_rw(const char *path, char *buf, size_t size,
+ off_t offset, int rw)
+{
+ uint32_t vid;
+ uint64_t oid;
+ unsigned long idx;
+ off_t start;
+ size_t len, ret;
+
+ if (shadow_file_getxattr(path, SH_VID_NAME, &vid, SH_VID_SIZE) < 0)
+ return -1;
+
+ idx = offset / SD_DATA_OBJ_SIZE;
+ oid = vid_to_data_oid(vid, idx);
+ start = offset % SD_DATA_OBJ_SIZE;
+
+ len = SD_DATA_OBJ_SIZE - start;
+ if (size < len)
+ len = size;
+
+ do {
+ syslog(LOG_ERR, "%s oid %"PRIx64", off %ju, len %zu,"
+ " size %zu\n",
+ rw == VOLUME_READ ? "read" : "write",
+ oid, start, len, size);
+ ret = volume_rw_object(buf, oid, len, start, rw);
+
+ if (ret != len)
+ return -1;
+
+ oid++;
+ size -= len;
+ start = (start + len) % SD_DATA_OBJ_SIZE;
+ buf += len;
+ len = size > SD_DATA_OBJ_SIZE ? SD_DATA_OBJ_SIZE : size;
+ } while (size > 0);
+
+ return 0;
+}
+
+int volume_read(const char *path, char *buf, size_t size, off_t offset)
+{
+
+ if (volume_do_rw(path, buf, size, offset, VOLUME_READ) < 0)
+ return -EIO;
+
+ return size;
+}
+
+int volume_write(const char *path, const char *buf, size_t size, off_t offset)
+{
+ if (volume_do_rw(path, (char *)buf, size, offset, VOLUME_WRITE) < 0)
+ return -EIO;
+
+ return size;
+}
+
+size_t volume_get_size(const char *path)
+{
+ size_t size = 0;
+
+ shadow_file_getxattr(path, SH_SIZE_NAME, &size, SH_SIZE_SIZE);
+ return size;
+}
+
+static int init_vdi_info(const char *entry, uint32_t *vid, size_t *size)
+{
+ struct strbuf *buf;
+ void *inode_buf;
+ struct vdi_inode *inode;
+ char command[256] = { 0 };
+ int ret = -1;
+
+ sprintf(command, "%s %s\n", "collie vdi list -r", entry);
+ buf = sheepfs_run_cmd(command);
+ if (!buf)
+ return -1;
+ if (sscanf(buf->buf, "%*s %*s %*d %zu %*s %*s %*s %"PRIx32,
+ size, vid) < 2) {
+ syslog(LOG_ERR, "[%s] %m\n", __func__);
+ goto out;
+ }
+
+ inode_buf = malloc(SD_INODE_SIZE);
+ if (!inode_buf) {
+ syslog(LOG_ERR, "[%s] %m\n", __func__);
+ goto out;
+ }
+
+ if (volume_rw_object(inode_buf, vid_to_vdi_oid(*vid), SD_INODE_SIZE,
+ 0, VOLUME_READ) < 0) {
+ free(inode_buf);
+ goto out;
+ }
+
+ inode = xzalloc(sizeof(*inode));
+ inode->vid = *vid;
+ inode->inode = inode_buf;
+ if (vdi_inode_tree_insert(inode)) {
+ free(inode_buf);
+ free(inode);
+ }
+ ret = 0;
+out:
+ strbuf_release(buf);
+ return ret;
+}
+
+int volume_create_entry(const char *entry)
+{
+ char path[PATH_MAX], *ch;
+ uint32_t vid;
+ size_t size;
+
+ ch = strchr(entry, '\n');
+ if (ch != NULL)
+ *ch = '\0';
+
+ sprintf(path, "%s/%s", PATH_VOLUME, entry);
+ if (shadow_file_exsit(path))
+ return 0;
+
+ if (shadow_file_create(path) < 0)
+ return -1;
+
+ if (init_vdi_info(entry, &vid, &size) < 0)
+ return -1;
+ if (shadow_file_setxattr(path, SH_VID_NAME, &vid, SH_VID_SIZE) < 0) {
+ shadow_file_delete(path);
+ return -1;
+ }
+ if (shadow_file_setxattr(path, SH_SIZE_NAME, &size, SH_SIZE_SIZE) < 0) {
+ shadow_file_delete(path);
+ return -1;
+ }
+ if (sheepfs_set_op(path, OP_VOLUME) < 0)
+ return -1;
+
+ return 0;
+}
--
1.7.8.2
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