Merge commit 'v2.6.30-rc1' into perfcounters/core

Conflicts:
	arch/powerpc/include/asm/systbl.h
	arch/powerpc/include/asm/unistd.h
	include/linux/init_task.h

Merge reason: the conflicts are non-trivial: PowerPC placement
              of sys_perf_counter_open has to be mixed with the
	      new preadv/pwrite syscalls.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 298 insertions, 0 deletions

diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h
new file mode 100644
index 000000000000..30fe58778d05
--- /dev/null
+++ b/fs/nilfs2/the_nilfs.h
@@ -0,0 +1,298 @@
+/*
+ * the_nilfs.h - the_nilfs shared structure.
+ *
+ * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
+ *
+ * This program 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Written by Ryusuke Konishi <ryusuke@osrg.net>
+ *
+ */
+
+#ifndef _THE_NILFS_H
+#define _THE_NILFS_H
+
+#include <linux/types.h>
+#include <linux/buffer_head.h>
+#include <linux/fs.h>
+#include <linux/blkdev.h>
+#include <linux/backing-dev.h>
+#include "sb.h"
+
+/* the_nilfs struct */
+enum {
+        THE_NILFS_INIT = 0,     /* Information from super_block is set */
+        THE_NILFS_LOADED,       /* Roll-back/roll-forward has done and
+                                   the latest checkpoint was loaded */
+        THE_NILFS_DISCONTINUED, /* 'next' pointer chain has broken */
+};
+
+/**
+ * struct the_nilfs - struct to supervise multiple nilfs mount points
+ * @ns_flags: flags
+ * @ns_count: reference count
+ * @ns_bdev: block device
+ * @ns_bdi: backing dev info
+ * @ns_writer: back pointer to writable nilfs_sb_info
+ * @ns_sem: semaphore for shared states
+ * @ns_writer_mutex: mutex protecting ns_writer attach/detach
+ * @ns_writer_refcount: number of referrers on ns_writer
+ * @ns_sbh: buffer heads of on-disk super blocks
+ * @ns_sbp: pointers to super block data
+ * @ns_sbwtime: previous write time of super blocks
+ * @ns_sbsize: size of valid data in super block
+ * @ns_supers: list of nilfs super block structs
+ * @ns_seg_seq: segment sequence counter
+ * @ns_segnum: index number of the latest full segment.
+ * @ns_nextnum: index number of the full segment index to be used next
+ * @ns_pseg_offset: offset of next partial segment in the current full segment
+ * @ns_cno: next checkpoint number
+ * @ns_ctime: write time of the last segment
+ * @ns_nongc_ctime: write time of the last segment not for cleaner operation
+ * @ns_ndirtyblks: Number of dirty data blocks
+ * @ns_last_segment_lock: lock protecting fields for the latest segment
+ * @ns_last_pseg: start block number of the latest segment
+ * @ns_last_seq: sequence value of the latest segment
+ * @ns_last_cno: checkpoint number of the latest segment
+ * @ns_prot_seq: least sequence number of segments which must not be reclaimed
+ * @ns_free_segments_count: counter of free segments
+ * @ns_segctor_sem: segment constructor semaphore
+ * @ns_dat: DAT file inode
+ * @ns_cpfile: checkpoint file inode
+ * @ns_sufile: segusage file inode
+ * @ns_gc_dat: shadow inode of the DAT file inode for GC
+ * @ns_gc_inodes: dummy inodes to keep live blocks
+ * @ns_gc_inodes_h: hash list to keep dummy inode holding live blocks
+ * @ns_blocksize_bits: bit length of block size
+ * @ns_nsegments: number of segments in filesystem
+ * @ns_blocks_per_segment: number of blocks per segment
+ * @ns_r_segments_percentage: reserved segments percentage
+ * @ns_nrsvsegs: number of reserved segments
+ * @ns_first_data_block: block number of first data block
+ * @ns_inode_size: size of on-disk inode
+ * @ns_first_ino: first not-special inode number
+ * @ns_crc_seed: seed value of CRC32 calculation
+ */
+struct the_nilfs {
+        unsigned long           ns_flags;
+        atomic_t                ns_count;
+
+        struct block_device    *ns_bdev;
+        struct backing_dev_info *ns_bdi;
+        struct nilfs_sb_info   *ns_writer;
+        struct rw_semaphore     ns_sem;
+        struct mutex            ns_writer_mutex;
+        atomic_t                ns_writer_refcount;
+
+        /*
+         * used for
+         * - loading the latest checkpoint exclusively.
+         * - allocating a new full segment.
+         * - protecting s_dirt in the super_block struct
+         *   (see nilfs_write_super) and the following fields.
+         */
+        struct buffer_head     *ns_sbh[2];
+        struct nilfs_super_block *ns_sbp[2];
+        time_t                  ns_sbwtime[2];
+        unsigned                ns_sbsize;
+        unsigned                ns_mount_state;
+        struct list_head        ns_supers;
+
+        /*
+         * Following fields are dedicated to a writable FS-instance.
+         * Except for the period seeking checkpoint, code outside the segment
+         * constructor must lock a segment semaphore while accessing these
+         * fields.
+         * The writable FS-instance is sole during a lifetime of the_nilfs.
+         */
+        u64                     ns_seg_seq;
+        __u64                   ns_segnum;
+        __u64                   ns_nextnum;
+        unsigned long           ns_pseg_offset;
+        __u64                   ns_cno;
+        time_t                  ns_ctime;
+        time_t                  ns_nongc_ctime;
+        atomic_t                ns_ndirtyblks;
+
+        /*
+         * The following fields hold information on the latest partial segment
+         * written to disk with a super root.  These fields are protected by
+         * ns_last_segment_lock.
+         */
+        spinlock_t              ns_last_segment_lock;
+        sector_t                ns_last_pseg;
+        u64                     ns_last_seq;
+        __u64                   ns_last_cno;
+        u64                     ns_prot_seq;
+        unsigned long           ns_free_segments_count;
+
+        struct rw_semaphore     ns_segctor_sem;
+
+        /*
+         * Following fields are lock free except for the period before
+         * the_nilfs is initialized.
+         */
+        struct inode           *ns_dat;
+        struct inode           *ns_cpfile;
+        struct inode           *ns_sufile;
+        struct inode           *ns_gc_dat;
+
+        /* GC inode list and hash table head */
+        struct list_head        ns_gc_inodes;
+        struct hlist_head      *ns_gc_inodes_h;
+
+        /* Disk layout information (static) */
+        unsigned int            ns_blocksize_bits;
+        unsigned long           ns_nsegments;
+        unsigned long           ns_blocks_per_segment;
+        unsigned long           ns_r_segments_percentage;
+        unsigned long           ns_nrsvsegs;
+        unsigned long           ns_first_data_block;
+        int                     ns_inode_size;
+        int                     ns_first_ino;
+        u32                     ns_crc_seed;
+};
+
+#define NILFS_GCINODE_HASH_BITS         8
+#define NILFS_GCINODE_HASH_SIZE         (1<<NILFS_GCINODE_HASH_BITS)
+
+#define THE_NILFS_FNS(bit, name)                                        \
+static inline void set_nilfs_##name(struct the_nilfs *nilfs)            \
+{                                                                       \
+        set_bit(THE_NILFS_##bit, &(nilfs)->ns_flags);                   \
+}                                                                       \
+static inline void clear_nilfs_##name(struct the_nilfs *nilfs)          \
+{                                                                       \
+        clear_bit(THE_NILFS_##bit, &(nilfs)->ns_flags);                 \
+}                                                                       \
+static inline int nilfs_##name(struct the_nilfs *nilfs)                 \
+{                                                                       \
+        return test_bit(THE_NILFS_##bit, &(nilfs)->ns_flags);           \
+}
+
+THE_NILFS_FNS(INIT, init)
+THE_NILFS_FNS(LOADED, loaded)
+THE_NILFS_FNS(DISCONTINUED, discontinued)
+
+/* Minimum interval of periodical update of superblocks (in seconds) */
+#define NILFS_SB_FREQ           10
+#define NILFS_ALTSB_FREQ        60  /* spare superblock */
+
+void nilfs_set_last_segment(struct the_nilfs *, sector_t, u64, __u64);
+struct the_nilfs *alloc_nilfs(struct block_device *);
+void put_nilfs(struct the_nilfs *);
+int init_nilfs(struct the_nilfs *, struct nilfs_sb_info *, char *);
+int load_nilfs(struct the_nilfs *, struct nilfs_sb_info *);
+int nilfs_count_free_blocks(struct the_nilfs *, sector_t *);
+int nilfs_checkpoint_is_mounted(struct the_nilfs *, __u64, int);
+int nilfs_near_disk_full(struct the_nilfs *);
+void nilfs_fall_back_super_block(struct the_nilfs *);
+void nilfs_swap_super_block(struct the_nilfs *);
+
+
+static inline void get_nilfs(struct the_nilfs *nilfs)
+{
+        /* Caller must have at least one reference of the_nilfs. */
+        atomic_inc(&nilfs->ns_count);
+}
+
+static inline struct nilfs_sb_info *nilfs_get_writer(struct the_nilfs *nilfs)
+{
+        if (atomic_inc_and_test(&nilfs->ns_writer_refcount))
+                mutex_lock(&nilfs->ns_writer_mutex);
+        return nilfs->ns_writer;
+}
+
+static inline void nilfs_put_writer(struct the_nilfs *nilfs)
+{
+        if (atomic_add_negative(-1, &nilfs->ns_writer_refcount))
+                mutex_unlock(&nilfs->ns_writer_mutex);
+}
+
+static inline void
+nilfs_attach_writer(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi)
+{
+        mutex_lock(&nilfs->ns_writer_mutex);
+        nilfs->ns_writer = sbi;
+        mutex_unlock(&nilfs->ns_writer_mutex);
+}
+
+static inline void
+nilfs_detach_writer(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi)
+{
+        mutex_lock(&nilfs->ns_writer_mutex);
+        if (sbi == nilfs->ns_writer)
+                nilfs->ns_writer = NULL;
+        mutex_unlock(&nilfs->ns_writer_mutex);
+}
+
+static inline void
+nilfs_get_segment_range(struct the_nilfs *nilfs, __u64 segnum,
+                        sector_t *seg_start, sector_t *seg_end)
+{
+        *seg_start = (sector_t)nilfs->ns_blocks_per_segment * segnum;
+        *seg_end = *seg_start + nilfs->ns_blocks_per_segment - 1;
+        if (segnum == 0)
+                *seg_start = nilfs->ns_first_data_block;
+}
+
+static inline sector_t
+nilfs_get_segment_start_blocknr(struct the_nilfs *nilfs, __u64 segnum)
+{
+        return (segnum == 0) ? nilfs->ns_first_data_block :
+                (sector_t)nilfs->ns_blocks_per_segment * segnum;
+}
+
+static inline __u64
+nilfs_get_segnum_of_block(struct the_nilfs *nilfs, sector_t blocknr)
+{
+        sector_t segnum = blocknr;
+
+        sector_div(segnum, nilfs->ns_blocks_per_segment);
+        return segnum;
+}
+
+static inline void
+nilfs_terminate_segment(struct the_nilfs *nilfs, sector_t seg_start,
+                        sector_t seg_end)
+{
+        /* terminate the current full segment (used in case of I/O-error) */
+        nilfs->ns_pseg_offset = seg_end - seg_start + 1;
+}
+
+static inline void nilfs_shift_to_next_segment(struct the_nilfs *nilfs)
+{
+        /* move forward with a full segment */
+        nilfs->ns_segnum = nilfs->ns_nextnum;
+        nilfs->ns_pseg_offset = 0;
+        nilfs->ns_seg_seq++;
+}
+
+static inline __u64 nilfs_last_cno(struct the_nilfs *nilfs)
+{
+        __u64 cno;
+
+        spin_lock(&nilfs->ns_last_segment_lock);
+        cno = nilfs->ns_last_cno;
+        spin_unlock(&nilfs->ns_last_segment_lock);
+        return cno;
+}
+
+static inline int nilfs_segment_is_active(struct the_nilfs *nilfs, __u64 n)
+{
+        return n == nilfs->ns_segnum || n == nilfs->ns_nextnum;
+}
+
+#endif /* _THE_NILFS_H */