[PATCH 1/8] exofs: Kbuild, Headers and osd utils

From: Boaz Harrosh
Date: Mon Feb 09 2009 - 08:12:30 EST


This patch includes osd infrastructure that will be used later by
the file system.

Also the declarations of constants, on disk structures,
and prototypes.

And the Kbuild+Kconfig files needed to build the exofs module.

Signed-off-by: Boaz Harrosh <bharrosh@xxxxxxxxxxx>
---
fs/exofs/Kbuild | 30 +++++++
fs/exofs/Kconfig | 13 +++
fs/exofs/common.h | 181 +++++++++++++++++++++++++++++++++++++++++
fs/exofs/exofs.h | 139 ++++++++++++++++++++++++++++++++
fs/exofs/osd.c | 230 +++++++++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 593 insertions(+), 0 deletions(-)
create mode 100644 fs/exofs/Kbuild
create mode 100644 fs/exofs/Kconfig
create mode 100644 fs/exofs/common.h
create mode 100644 fs/exofs/exofs.h
create mode 100644 fs/exofs/osd.c

diff --git a/fs/exofs/Kbuild b/fs/exofs/Kbuild
new file mode 100644
index 0000000..c806738
--- /dev/null
+++ b/fs/exofs/Kbuild
@@ -0,0 +1,30 @@
+#
+# Kbuild for the EXOFS module
+#
+# Copyright (C) 2008 Panasas Inc. All rights reserved.
+#
+# Authors:
+# Boaz Harrosh <bharrosh@xxxxxxxxxxx>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2
+#
+# Kbuild - Gets included from the Kernels Makefile and build system
+#
+
+ifneq ($(OSD_INC),)
+# we are built out-of-tree Kconfigure everything as on
+
+CONFIG_EXOFS_FS=m
+ccflags-y += -DCONFIG_EXOFS_FS -DCONFIG_EXOFS_FS_MODULE
+# ccflags-y += -DCONFIG_EXOFS_DEBUG
+
+# if we are built out-of-tree and the hosting kernel has OSD headers
+# then "ccflags-y +=" will not pick the out-off-tree headers. Only by doing
+# this it will work. This might break in future kernels
+KBUILD_CPPFLAGS := -I$(OSD_INC) $(KBUILD_CPPFLAGS)
+
+endif
+
+exofs-objs := osd.o
+obj-$(CONFIG_EXOFS_FS) += exofs.o
diff --git a/fs/exofs/Kconfig b/fs/exofs/Kconfig
new file mode 100644
index 0000000..86194b2
--- /dev/null
+++ b/fs/exofs/Kconfig
@@ -0,0 +1,13 @@
+config EXOFS_FS
+ tristate "exofs: OSD based file system support"
+ depends on SCSI_OSD_ULD
+ help
+ EXOFS is a file system that uses an OSD storage device,
+ as its backing storage.
+
+# Debugging-related stuff
+config EXOFS_DEBUG
+ bool "Enable debugging"
+ depends on EXOFS_FS
+ help
+ This option enables EXOFS debug prints.
diff --git a/fs/exofs/common.h b/fs/exofs/common.h
new file mode 100644
index 0000000..894487e
--- /dev/null
+++ b/fs/exofs/common.h
@@ -0,0 +1,181 @@
+/*
+ * common.h - Common definitions for both Kernel and user-mode utilities
+ *
+ * Copyright (C) 2005, 2006
+ * Avishay Traeger (avishay@xxxxxxxxx) (avishay@xxxxxxxxxx)
+ * Copyright (C) 2005, 2006
+ * International Business Machines
+ * Copyright (C) 2008, 2009
+ * Boaz Harrosh <bharrosh@xxxxxxxxxxx>
+ *
+ * Copyrights for code taken from ext2:
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@xxxxxxxxxxx)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ * from
+ * linux/fs/minix/inode.c
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * This file is part of exofs.
+ *
+ * exofs is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation. Since it is based on ext2, and the only
+ * valid version of GPL for the Linux kernel is version 2, the only valid
+ * version of GPL for exofs is version 2.
+ *
+ * exofs is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with exofs; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef __EXOFS_COM_H__
+#define __EXOFS_COM_H__
+
+#include <linux/types.h>
+
+#include <scsi/osd_attributes.h>
+#include <scsi/osd_initiator.h>
+#include <scsi/osd_sec.h>
+
+/****************************************************************************
+ * Object ID related defines
+ * NOTE: inode# = object ID - EXOFS_OBJ_OFF
+ ****************************************************************************/
+#define EXOFS_MIN_PID 0x10000 /* Smallest partition ID */
+#define EXOFS_OBJ_OFF 0x10000 /* offset for objects */
+#define EXOFS_SUPER_ID 0x10000 /* object ID for on-disk superblock */
+#define EXOFS_ROOT_ID 0x10002 /* object ID for root directory */
+
+/* exofs Application specific page/attribute */
+# define EXOFS_APAGE_FS_DATA (OSD_APAGE_APP_DEFINED_FIRST + 3)
+# define EXOFS_ATTR_INODE_DATA 1
+
+/*
+ * The maximum number of files we can have is limited by the size of the
+ * inode number. This is the largest object ID that the file system supports.
+ * Object IDs 0, 1, and 2 are always in use (see above defines).
+ */
+enum {
+ EXOFS_UINT64_MAX = (~0LL),
+ EXOFS_MAX_INO_ID = (sizeof(ino_t) * 8 == 64) ? EXOFS_UINT64_MAX :
+ (1LL << (sizeof(ino_t) * 8 - 1)),
+ EXOFS_MAX_ID = (EXOFS_MAX_INO_ID - 1 - EXOFS_OBJ_OFF),
+};
+
+/****************************************************************************
+ * Misc.
+ ****************************************************************************/
+#define EXOFS_BLKSHIFT 12
+#define EXOFS_BLKSIZE (1UL << EXOFS_BLKSHIFT)
+
+/****************************************************************************
+ * superblock-related things
+ ****************************************************************************/
+#define EXOFS_SUPER_MAGIC 0x5DF5
+
+/*
+ * The file system control block - stored in an object's data (mainly, the one
+ * with ID EXOFS_SUPER_ID). This is where the in-memory superblock is stored
+ * on disk. Right now it just has a magic value, which is basically a sanity
+ * check on our ability to communicate with the object store.
+ */
+struct exofs_fscb {
+ __le64 s_nextid; /* Highest object ID used */
+ __le32 s_numfiles; /* Number of files on fs */
+ __le16 s_magic; /* Magic signature */
+ __le16 s_newfs; /* Non-zero if this is a new fs */
+};
+
+/****************************************************************************
+ * inode-related things
+ ****************************************************************************/
+#define EXOFS_IDATA 5
+
+/*
+ * The file control block - stored in an object's attributes. This is where
+ * the in-memory inode is stored on disk.
+ */
+struct exofs_fcb {
+ __le64 i_size; /* Size of the file */
+ __le16 i_mode; /* File mode */
+ __le16 i_links_count; /* Links count */
+ __le32 i_uid; /* Owner Uid */
+ __le32 i_gid; /* Group Id */
+ __le32 i_atime; /* Access time */
+ __le32 i_ctime; /* Creation time */
+ __le32 i_mtime; /* Modification time */
+ __le32 i_flags; /* File flags (unused for now)*/
+ __le32 i_generation; /* File version (for NFS) */
+ __le32 i_data[EXOFS_IDATA]; /* Short symlink names and device #s */
+};
+
+#define EXOFS_INO_ATTR_SIZE sizeof(struct exofs_fcb)
+
+/* This is the Attribute the fcb is stored in */
+static const struct __weak osd_attr g_attr_inode_data = ATTR_DEF(
+ EXOFS_APAGE_FS_DATA,
+ EXOFS_ATTR_INODE_DATA,
+ EXOFS_INO_ATTR_SIZE);
+
+/****************************************************************************
+ * dentry-related things
+ ****************************************************************************/
+#define EXOFS_NAME_LEN 255
+
+/*
+ * The on-disk directory entry
+ */
+struct exofs_dir_entry {
+ __le64 inode_no; /* inode number */
+ __le16 rec_len; /* directory entry length */
+ u8 name_len; /* name length */
+ u8 file_type; /* umm...file type */
+ char name[EXOFS_NAME_LEN]; /* file name */
+};
+
+enum {
+ EXOFS_FT_UNKNOWN,
+ EXOFS_FT_REG_FILE,
+ EXOFS_FT_DIR,
+ EXOFS_FT_CHRDEV,
+ EXOFS_FT_BLKDEV,
+ EXOFS_FT_FIFO,
+ EXOFS_FT_SOCK,
+ EXOFS_FT_SYMLINK,
+ EXOFS_FT_MAX
+};
+
+#define EXOFS_DIR_PAD 4
+#define EXOFS_DIR_ROUND (EXOFS_DIR_PAD - 1)
+#define EXOFS_DIR_REC_LEN(name_len) \
+ (((name_len) + offsetof(struct exofs_dir_entry, name) + \
+ EXOFS_DIR_ROUND) & ~EXOFS_DIR_ROUND)
+
+/*************************
+ * function declarations *
+ *************************/
+/* osd.c */
+void exofs_make_credential(u8 cred_a[OSD_CAP_LEN],
+ const struct osd_obj_id *obj);
+
+int exofs_check_ok(struct osd_request *or);
+int exofs_sync_op(struct osd_request *or, int timeout, u8 *cred);
+int exofs_async_op(struct osd_request *or,
+ osd_req_done_fn *async_done, void *caller_context, u8 *cred);
+
+int extract_attr_from_req(struct osd_request *or, struct osd_attr *attr);
+
+int osd_req_read_kern(struct osd_request *or,
+ const struct osd_obj_id *obj, u64 offset, void *buff, u64 len);
+
+int osd_req_write_kern(struct osd_request *or,
+ const struct osd_obj_id *obj, u64 offset, void *buff, u64 len);
+
+#endif /*ifndef __EXOFS_COM_H__*/
diff --git a/fs/exofs/exofs.h b/fs/exofs/exofs.h
new file mode 100644
index 0000000..0637237
--- /dev/null
+++ b/fs/exofs/exofs.h
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2005, 2006
+ * Avishay Traeger (avishay@xxxxxxxxx) (avishay@xxxxxxxxxx)
+ * Copyright (C) 2005, 2006
+ * International Business Machines
+ * Copyright (C) 2008, 2009
+ * Boaz Harrosh <bharrosh@xxxxxxxxxxx>
+ *
+ * Copyrights for code taken from ext2:
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@xxxxxxxxxxx)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ * from
+ * linux/fs/minix/inode.c
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * This file is part of exofs.
+ *
+ * exofs is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation. Since it is based on ext2, and the only
+ * valid version of GPL for the Linux kernel is version 2, the only valid
+ * version of GPL for exofs is version 2.
+ *
+ * exofs is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with exofs; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/fs.h>
+#include <linux/time.h>
+#include "common.h"
+
+#ifndef __EXOFS_H__
+#define __EXOFS_H__
+
+#define EXOFS_ERR(fmt, a...) printk(KERN_ERR "exofs: " fmt, ##a)
+
+#ifdef CONFIG_EXOFS_DEBUG
+#define EXOFS_DBGMSG(fmt, a...) \
+ printk(KERN_NOTICE "exofs @%s:%d: " fmt, __func__, __LINE__, ##a)
+#else
+#define EXOFS_DBGMSG(fmt, a...) \
+ do {} while (0)
+#endif
+
+/* u64 has problems with printk this will cast it to unsigned long long */
+#define _LLU(x) (unsigned long long)(x)
+
+/*
+ * our extension to the in-memory superblock
+ */
+struct exofs_sb_info {
+ struct osd_dev *s_dev; /* returned by get_osd_dev */
+ osd_id s_pid; /* partition ID of file system*/
+ int s_timeout; /* timeout for OSD operations */
+ uint64_t s_nextid; /* highest object ID used */
+ uint32_t s_numfiles; /* number of files on fs */
+ spinlock_t s_next_gen_lock; /* spinlock for gen # update */
+ u32 s_next_generation; /* next gen # to use */
+ atomic_t s_curr_pending; /* number of pending commands */
+ uint8_t s_cred[OSD_CAP_LEN]; /* all-powerful credential */
+};
+
+/*
+ * our extension to the in-memory inode
+ */
+struct exofs_i_info {
+ unsigned long i_flags; /* various atomic flags */
+ uint32_t i_data[EXOFS_IDATA];/*short symlink names and device #s*/
+ uint32_t i_dir_start_lookup; /* which page to start lookup */
+ wait_queue_head_t i_wq; /* wait queue for inode */
+ uint64_t i_commit_size; /* the object's written length */
+ uint8_t i_cred[OSD_CAP_LEN];/* all-powerful credential */
+ struct inode vfs_inode; /* normal in-memory inode */
+};
+
+/*
+ * our inode flags
+ */
+#define OBJ_2BCREATED 0 /* object will be created soon*/
+#define OBJ_CREATED 1 /* object has been created on the osd*/
+
+static inline int obj_2bcreated(struct exofs_i_info *oi)
+{
+ return test_bit(OBJ_2BCREATED, &(oi->i_flags));
+}
+
+static inline void set_obj_2bcreated(struct exofs_i_info *oi)
+{
+ set_bit(OBJ_2BCREATED, &(oi->i_flags));
+}
+
+static inline int obj_created(struct exofs_i_info *oi)
+{
+ return test_bit(OBJ_CREATED, &(oi->i_flags));
+}
+
+static inline void set_obj_created(struct exofs_i_info *oi)
+{
+ set_bit(OBJ_CREATED, &(oi->i_flags));
+}
+
+int __exofs_wait_obj_created(struct exofs_i_info *oi);
+static inline int wait_obj_created(struct exofs_i_info *oi)
+{
+ if (likely(obj_created(oi)))
+ return 0;
+
+ return __exofs_wait_obj_created(oi);
+}
+
+/*
+ * get to our inode from the vfs inode
+ */
+static inline struct exofs_i_info *exofs_i(struct inode *inode)
+{
+ return container_of(inode, struct exofs_i_info, vfs_inode);
+}
+
+/*************************
+ * function declarations *
+ *************************/
+/* osd.c */
+int osd_req_read_pages(struct osd_request *or,
+ const struct osd_obj_id *, u64 offset, u64 length,
+ struct page **pages, int page_count);
+
+int osd_req_write_pages(struct osd_request *or,
+ const struct osd_obj_id *, u64 offset, u64 length,
+ struct page **pages, int page_count);
+
+#endif
diff --git a/fs/exofs/osd.c b/fs/exofs/osd.c
new file mode 100644
index 0000000..84c573d
--- /dev/null
+++ b/fs/exofs/osd.c
@@ -0,0 +1,230 @@
+/*
+ * Copyright (C) 2005, 2006
+ * Avishay Traeger (avishay@xxxxxxxxx) (avishay@xxxxxxxxxx)
+ * Copyright (C) 2005, 2006
+ * International Business Machines
+ * Copyright (C) 2008, 2009
+ * Boaz Harrosh <bharrosh@xxxxxxxxxxx>
+ *
+ * This file is part of exofs.
+ *
+ * exofs is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation. Since it is based on ext2, and the only
+ * valid version of GPL for the Linux kernel is version 2, the only valid
+ * version of GPL for exofs is version 2.
+ *
+ * exofs is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with exofs; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <scsi/scsi_device.h>
+#include <scsi/osd_sense.h>
+
+#include "exofs.h"
+
+int exofs_check_ok(struct osd_request *or)
+{
+ struct osd_sense_info osi;
+ int ret = osd_req_decode_sense(or, &osi);
+
+ if (ret) { /* translate to Linux codes */
+ if (osi.additional_code == scsi_invalid_field_in_cdb) {
+ if (osi.cdb_field_offset == OSD_CFO_STARTING_BYTE)
+ ret = -EFAULT;
+ if (osi.cdb_field_offset == OSD_CFO_OBJECT_ID)
+ ret = -ENOENT;
+ else
+ ret = -EINVAL;
+ } else if (osi.additional_code == osd_quota_error)
+ ret = -ENOSPC;
+ else
+ ret = -EIO;
+ }
+
+ return ret;
+}
+
+void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
+{
+ osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
+}
+
+/*
+ * Perform a synchronous OSD operation.
+ */
+int exofs_sync_op(struct osd_request *or, int timeout, uint8_t *credential)
+{
+ int ret;
+
+ or->timeout = timeout;
+ ret = osd_finalize_request(or, 0, credential, NULL);
+ if (ret) {
+ EXOFS_DBGMSG("Faild to osd_finalize_request() => %d\n", ret);
+ return ret;
+ }
+
+ ret = osd_execute_request(or);
+
+ if (ret)
+ EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
+ /* osd_req_decode_sense(or, ret); */
+ return ret;
+}
+
+/*
+ * Perform an asynchronous OSD operation.
+ */
+int exofs_async_op(struct osd_request *or, osd_req_done_fn *async_done,
+ void *caller_context, u8 *cred)
+{
+ int ret;
+
+ ret = osd_finalize_request(or, 0, cred, NULL);
+ if (ret) {
+ EXOFS_DBGMSG("Faild to osd_finalize_request() => %d\n", ret);
+ return ret;
+ }
+
+ ret = osd_execute_request_async(or, async_done, caller_context);
+
+ if (ret)
+ EXOFS_DBGMSG("osd_execute_request_async() => %d\n", ret);
+ return ret;
+}
+
+int extract_attr_from_req(struct osd_request *or, struct osd_attr *attr)
+{
+ struct osd_attr cur_attr = {.attr_page = 0}; /* start with zeros */
+ void *iter = NULL;
+ int nelem;
+
+ do {
+ nelem = 1;
+ osd_req_decode_get_attr_list(or, &cur_attr, &nelem, &iter);
+ if ((cur_attr.attr_page == attr->attr_page) &&
+ (cur_attr.attr_id == attr->attr_id)) {
+ attr->len = cur_attr.len;
+ attr->val_ptr = cur_attr.val_ptr;
+ return 0;
+ }
+ } while (iter);
+
+ return -EIO;
+}
+
+static void _osd_read(struct osd_request *or,
+ const struct osd_obj_id *obj, uint64_t offset, struct bio *bio)
+{
+ osd_req_read(or, obj, bio, offset);
+ EXOFS_DBGMSG("osd_req_read(p=%llX, ob=%llX, l=%llu, of=%llu)\n",
+ _LLU(obj->partition), _LLU(obj->id), _LLU(bio->bi_size),
+ _LLU(offset));
+}
+
+#ifdef __KERNEL__
+static struct bio *_bio_map_pages(struct request_queue *req_q,
+ struct page **pages, unsigned page_count,
+ size_t length, gfp_t gfp_mask)
+{
+ struct bio *bio;
+ int i;
+
+ bio = bio_alloc(gfp_mask, page_count);
+ if (!bio) {
+ EXOFS_DBGMSG("Failed to bio_alloc page_count=%d\n", page_count);
+ return NULL;
+ }
+
+ for (i = 0; i < page_count && length; i++) {
+ size_t use_len = min(length, PAGE_SIZE);
+
+ if (use_len !=
+ bio_add_pc_page(req_q, bio, pages[i], use_len, 0)) {
+ EXOFS_ERR("Failed bio_add_pc_page req_q=%p pages[i]=%p "
+ "use_len=%Zd page_count=%d length=%Zd\n",
+ req_q, pages[i], use_len, page_count, length);
+ bio_put(bio);
+ return NULL;
+ }
+
+ length -= use_len;
+ }
+
+ WARN_ON(length);
+ return bio;
+}
+
+int osd_req_read_pages(struct osd_request *or,
+ const struct osd_obj_id *obj, u64 offset, u64 length,
+ struct page **pages, int page_count)
+{
+ struct request_queue *req_q = or->osd_dev->scsi_device->request_queue;
+ struct bio *bio = _bio_map_pages(req_q, pages, page_count, length,
+ GFP_KERNEL);
+
+ if (!bio)
+ return -ENOMEM;
+
+ _osd_read(or, obj, offset, bio);
+ return 0;
+}
+#endif /* def __KERNEL__ */
+
+int osd_req_read_kern(struct osd_request *or,
+ const struct osd_obj_id *obj, u64 offset, void* buff, u64 len)
+{
+ struct request_queue *req_q = or->osd_dev->scsi_device->request_queue;
+ struct bio *bio = bio_map_kern(req_q, buff, len, GFP_KERNEL);
+
+ if (!bio)
+ return -ENOMEM;
+
+ _osd_read(or, obj, offset, bio);
+ return 0;
+}
+
+static void _osd_write(struct osd_request *or,
+ const struct osd_obj_id *obj, uint64_t offset, struct bio *bio)
+{
+ osd_req_write(or, obj, bio, offset);
+ EXOFS_DBGMSG("osd_req_write(p=%llX, ob=%llX, l=%llu, of=%llu)\n",
+ _LLU(obj->partition), _LLU(obj->id), _LLU(bio->bi_size),
+ _LLU(offset));
+}
+
+#ifdef __KERNEL__
+int osd_req_write_pages(struct osd_request *or,
+ const struct osd_obj_id *obj, u64 offset, u64 length,
+ struct page **pages, int page_count)
+{
+ struct request_queue *req_q = or->osd_dev->scsi_device->request_queue;
+ struct bio *bio = _bio_map_pages(req_q, pages, page_count, length,
+ GFP_KERNEL);
+
+ if (!bio)
+ return -ENOMEM;
+
+ _osd_write(or, obj, offset, bio);
+ return 0;
+}
+#endif /* def __KERNEL__ */
+
+int osd_req_write_kern(struct osd_request *or,
+ const struct osd_obj_id *obj, u64 offset, void* buff, u64 len)
+{
+ struct request_queue *req_q = or->osd_dev->scsi_device->request_queue;
+ struct bio *bio = bio_map_kern(req_q, buff, len, GFP_KERNEL);
+
+ if (!bio)
+ return -ENOMEM;
+
+ _osd_write(or, obj, offset, bio);
+ return 0;
+}
--
1.6.0.1

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