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-rw-r--r--fs/nilfs2/super.c1502
1 files changed, 1502 insertions, 0 deletions
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
new file mode 100644
index 000000000..9ba493308
--- /dev/null
+++ b/fs/nilfs2/super.c
@@ -0,0 +1,1502 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * NILFS module and super block management.
+ *
+ * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
+ *
+ * Written by Ryusuke Konishi.
+ */
+/*
+ * linux/fs/ext2/super.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/fs/minix/inode.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <linux/parser.h>
+#include <linux/crc32.h>
+#include <linux/vfs.h>
+#include <linux/writeback.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include "nilfs.h"
+#include "export.h"
+#include "mdt.h"
+#include "alloc.h"
+#include "btree.h"
+#include "btnode.h"
+#include "page.h"
+#include "cpfile.h"
+#include "sufile.h" /* nilfs_sufile_resize(), nilfs_sufile_set_alloc_range() */
+#include "ifile.h"
+#include "dat.h"
+#include "segment.h"
+#include "segbuf.h"
+
+MODULE_AUTHOR("NTT Corp.");
+MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
+ "(NILFS)");
+MODULE_LICENSE("GPL");
+
+static struct kmem_cache *nilfs_inode_cachep;
+struct kmem_cache *nilfs_transaction_cachep;
+struct kmem_cache *nilfs_segbuf_cachep;
+struct kmem_cache *nilfs_btree_path_cache;
+
+static int nilfs_setup_super(struct super_block *sb, int is_mount);
+static int nilfs_remount(struct super_block *sb, int *flags, char *data);
+
+void __nilfs_msg(struct super_block *sb, const char *fmt, ...)
+{
+ struct va_format vaf;
+ va_list args;
+ int level;
+
+ va_start(args, fmt);
+
+ level = printk_get_level(fmt);
+ vaf.fmt = printk_skip_level(fmt);
+ vaf.va = &args;
+
+ if (sb)
+ printk("%c%cNILFS (%s): %pV\n",
+ KERN_SOH_ASCII, level, sb->s_id, &vaf);
+ else
+ printk("%c%cNILFS: %pV\n",
+ KERN_SOH_ASCII, level, &vaf);
+
+ va_end(args);
+}
+
+static void nilfs_set_error(struct super_block *sb)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_super_block **sbp;
+
+ down_write(&nilfs->ns_sem);
+ if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
+ nilfs->ns_mount_state |= NILFS_ERROR_FS;
+ sbp = nilfs_prepare_super(sb, 0);
+ if (likely(sbp)) {
+ sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
+ if (sbp[1])
+ sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
+ nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
+ }
+ }
+ up_write(&nilfs->ns_sem);
+}
+
+/**
+ * __nilfs_error() - report failure condition on a filesystem
+ *
+ * __nilfs_error() sets an ERROR_FS flag on the superblock as well as
+ * reporting an error message. This function should be called when
+ * NILFS detects incoherences or defects of meta data on disk.
+ *
+ * This implements the body of nilfs_error() macro. Normally,
+ * nilfs_error() should be used. As for sustainable errors such as a
+ * single-shot I/O error, nilfs_err() should be used instead.
+ *
+ * Callers should not add a trailing newline since this will do it.
+ */
+void __nilfs_error(struct super_block *sb, const char *function,
+ const char *fmt, ...)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct va_format vaf;
+ va_list args;
+
+ va_start(args, fmt);
+
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+ printk(KERN_CRIT "NILFS error (device %s): %s: %pV\n",
+ sb->s_id, function, &vaf);
+
+ va_end(args);
+
+ if (!sb_rdonly(sb)) {
+ nilfs_set_error(sb);
+
+ if (nilfs_test_opt(nilfs, ERRORS_RO)) {
+ printk(KERN_CRIT "Remounting filesystem read-only\n");
+ sb->s_flags |= SB_RDONLY;
+ }
+ }
+
+ if (nilfs_test_opt(nilfs, ERRORS_PANIC))
+ panic("NILFS (device %s): panic forced after error\n",
+ sb->s_id);
+}
+
+struct inode *nilfs_alloc_inode(struct super_block *sb)
+{
+ struct nilfs_inode_info *ii;
+
+ ii = alloc_inode_sb(sb, nilfs_inode_cachep, GFP_NOFS);
+ if (!ii)
+ return NULL;
+ ii->i_bh = NULL;
+ ii->i_state = 0;
+ ii->i_cno = 0;
+ ii->i_assoc_inode = NULL;
+ ii->i_bmap = &ii->i_bmap_data;
+ return &ii->vfs_inode;
+}
+
+static void nilfs_free_inode(struct inode *inode)
+{
+ if (nilfs_is_metadata_file_inode(inode))
+ nilfs_mdt_destroy(inode);
+
+ kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
+}
+
+static int nilfs_sync_super(struct super_block *sb, int flag)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ int err;
+
+ retry:
+ set_buffer_dirty(nilfs->ns_sbh[0]);
+ if (nilfs_test_opt(nilfs, BARRIER)) {
+ err = __sync_dirty_buffer(nilfs->ns_sbh[0],
+ REQ_SYNC | REQ_PREFLUSH | REQ_FUA);
+ } else {
+ err = sync_dirty_buffer(nilfs->ns_sbh[0]);
+ }
+
+ if (unlikely(err)) {
+ nilfs_err(sb, "unable to write superblock: err=%d", err);
+ if (err == -EIO && nilfs->ns_sbh[1]) {
+ /*
+ * sbp[0] points to newer log than sbp[1],
+ * so copy sbp[0] to sbp[1] to take over sbp[0].
+ */
+ memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0],
+ nilfs->ns_sbsize);
+ nilfs_fall_back_super_block(nilfs);
+ goto retry;
+ }
+ } else {
+ struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
+
+ nilfs->ns_sbwcount++;
+
+ /*
+ * The latest segment becomes trailable from the position
+ * written in superblock.
+ */
+ clear_nilfs_discontinued(nilfs);
+
+ /* update GC protection for recent segments */
+ if (nilfs->ns_sbh[1]) {
+ if (flag == NILFS_SB_COMMIT_ALL) {
+ set_buffer_dirty(nilfs->ns_sbh[1]);
+ if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0)
+ goto out;
+ }
+ if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) <
+ le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno))
+ sbp = nilfs->ns_sbp[1];
+ }
+
+ spin_lock(&nilfs->ns_last_segment_lock);
+ nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
+ spin_unlock(&nilfs->ns_last_segment_lock);
+ }
+ out:
+ return err;
+}
+
+void nilfs_set_log_cursor(struct nilfs_super_block *sbp,
+ struct the_nilfs *nilfs)
+{
+ sector_t nfreeblocks;
+
+ /* nilfs->ns_sem must be locked by the caller. */
+ nilfs_count_free_blocks(nilfs, &nfreeblocks);
+ sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks);
+
+ spin_lock(&nilfs->ns_last_segment_lock);
+ sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
+ sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
+ sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
+ spin_unlock(&nilfs->ns_last_segment_lock);
+}
+
+struct nilfs_super_block **nilfs_prepare_super(struct super_block *sb,
+ int flip)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_super_block **sbp = nilfs->ns_sbp;
+
+ /* nilfs->ns_sem must be locked by the caller. */
+ if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
+ if (sbp[1] &&
+ sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) {
+ memcpy(sbp[0], sbp[1], nilfs->ns_sbsize);
+ } else {
+ nilfs_crit(sb, "superblock broke");
+ return NULL;
+ }
+ } else if (sbp[1] &&
+ sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
+ memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
+ }
+
+ if (flip && sbp[1])
+ nilfs_swap_super_block(nilfs);
+
+ return sbp;
+}
+
+int nilfs_commit_super(struct super_block *sb, int flag)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_super_block **sbp = nilfs->ns_sbp;
+ time64_t t;
+
+ /* nilfs->ns_sem must be locked by the caller. */
+ t = ktime_get_real_seconds();
+ nilfs->ns_sbwtime = t;
+ sbp[0]->s_wtime = cpu_to_le64(t);
+ sbp[0]->s_sum = 0;
+ sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
+ (unsigned char *)sbp[0],
+ nilfs->ns_sbsize));
+ if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) {
+ sbp[1]->s_wtime = sbp[0]->s_wtime;
+ sbp[1]->s_sum = 0;
+ sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
+ (unsigned char *)sbp[1],
+ nilfs->ns_sbsize));
+ }
+ clear_nilfs_sb_dirty(nilfs);
+ nilfs->ns_flushed_device = 1;
+ /* make sure store to ns_flushed_device cannot be reordered */
+ smp_wmb();
+ return nilfs_sync_super(sb, flag);
+}
+
+/**
+ * nilfs_cleanup_super() - write filesystem state for cleanup
+ * @sb: super block instance to be unmounted or degraded to read-only
+ *
+ * This function restores state flags in the on-disk super block.
+ * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
+ * filesystem was not clean previously.
+ */
+int nilfs_cleanup_super(struct super_block *sb)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_super_block **sbp;
+ int flag = NILFS_SB_COMMIT;
+ int ret = -EIO;
+
+ sbp = nilfs_prepare_super(sb, 0);
+ if (sbp) {
+ sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state);
+ nilfs_set_log_cursor(sbp[0], nilfs);
+ if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) {
+ /*
+ * make the "clean" flag also to the opposite
+ * super block if both super blocks point to
+ * the same checkpoint.
+ */
+ sbp[1]->s_state = sbp[0]->s_state;
+ flag = NILFS_SB_COMMIT_ALL;
+ }
+ ret = nilfs_commit_super(sb, flag);
+ }
+ return ret;
+}
+
+/**
+ * nilfs_move_2nd_super - relocate secondary super block
+ * @sb: super block instance
+ * @sb2off: new offset of the secondary super block (in bytes)
+ */
+static int nilfs_move_2nd_super(struct super_block *sb, loff_t sb2off)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct buffer_head *nsbh;
+ struct nilfs_super_block *nsbp;
+ sector_t blocknr, newblocknr;
+ unsigned long offset;
+ int sb2i; /* array index of the secondary superblock */
+ int ret = 0;
+
+ /* nilfs->ns_sem must be locked by the caller. */
+ if (nilfs->ns_sbh[1] &&
+ nilfs->ns_sbh[1]->b_blocknr > nilfs->ns_first_data_block) {
+ sb2i = 1;
+ blocknr = nilfs->ns_sbh[1]->b_blocknr;
+ } else if (nilfs->ns_sbh[0]->b_blocknr > nilfs->ns_first_data_block) {
+ sb2i = 0;
+ blocknr = nilfs->ns_sbh[0]->b_blocknr;
+ } else {
+ sb2i = -1;
+ blocknr = 0;
+ }
+ if (sb2i >= 0 && (u64)blocknr << nilfs->ns_blocksize_bits == sb2off)
+ goto out; /* super block location is unchanged */
+
+ /* Get new super block buffer */
+ newblocknr = sb2off >> nilfs->ns_blocksize_bits;
+ offset = sb2off & (nilfs->ns_blocksize - 1);
+ nsbh = sb_getblk(sb, newblocknr);
+ if (!nsbh) {
+ nilfs_warn(sb,
+ "unable to move secondary superblock to block %llu",
+ (unsigned long long)newblocknr);
+ ret = -EIO;
+ goto out;
+ }
+ nsbp = (void *)nsbh->b_data + offset;
+
+ lock_buffer(nsbh);
+ if (sb2i >= 0) {
+ /*
+ * The position of the second superblock only changes by 4KiB,
+ * which is larger than the maximum superblock data size
+ * (= 1KiB), so there is no need to use memmove() to allow
+ * overlap between source and destination.
+ */
+ memcpy(nsbp, nilfs->ns_sbp[sb2i], nilfs->ns_sbsize);
+
+ /*
+ * Zero fill after copy to avoid overwriting in case of move
+ * within the same block.
+ */
+ memset(nsbh->b_data, 0, offset);
+ memset((void *)nsbp + nilfs->ns_sbsize, 0,
+ nsbh->b_size - offset - nilfs->ns_sbsize);
+ } else {
+ memset(nsbh->b_data, 0, nsbh->b_size);
+ }
+ set_buffer_uptodate(nsbh);
+ unlock_buffer(nsbh);
+
+ if (sb2i >= 0) {
+ brelse(nilfs->ns_sbh[sb2i]);
+ nilfs->ns_sbh[sb2i] = nsbh;
+ nilfs->ns_sbp[sb2i] = nsbp;
+ } else if (nilfs->ns_sbh[0]->b_blocknr < nilfs->ns_first_data_block) {
+ /* secondary super block will be restored to index 1 */
+ nilfs->ns_sbh[1] = nsbh;
+ nilfs->ns_sbp[1] = nsbp;
+ } else {
+ brelse(nsbh);
+ }
+out:
+ return ret;
+}
+
+/**
+ * nilfs_resize_fs - resize the filesystem
+ * @sb: super block instance
+ * @newsize: new size of the filesystem (in bytes)
+ */
+int nilfs_resize_fs(struct super_block *sb, __u64 newsize)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_super_block **sbp;
+ __u64 devsize, newnsegs;
+ loff_t sb2off;
+ int ret;
+
+ ret = -ERANGE;
+ devsize = bdev_nr_bytes(sb->s_bdev);
+ if (newsize > devsize)
+ goto out;
+
+ /*
+ * Prevent underflow in second superblock position calculation.
+ * The exact minimum size check is done in nilfs_sufile_resize().
+ */
+ if (newsize < 4096) {
+ ret = -ENOSPC;
+ goto out;
+ }
+
+ /*
+ * Write lock is required to protect some functions depending
+ * on the number of segments, the number of reserved segments,
+ * and so forth.
+ */
+ down_write(&nilfs->ns_segctor_sem);
+
+ sb2off = NILFS_SB2_OFFSET_BYTES(newsize);
+ newnsegs = sb2off >> nilfs->ns_blocksize_bits;
+ do_div(newnsegs, nilfs->ns_blocks_per_segment);
+
+ ret = nilfs_sufile_resize(nilfs->ns_sufile, newnsegs);
+ up_write(&nilfs->ns_segctor_sem);
+ if (ret < 0)
+ goto out;
+
+ ret = nilfs_construct_segment(sb);
+ if (ret < 0)
+ goto out;
+
+ down_write(&nilfs->ns_sem);
+ nilfs_move_2nd_super(sb, sb2off);
+ ret = -EIO;
+ sbp = nilfs_prepare_super(sb, 0);
+ if (likely(sbp)) {
+ nilfs_set_log_cursor(sbp[0], nilfs);
+ /*
+ * Drop NILFS_RESIZE_FS flag for compatibility with
+ * mount-time resize which may be implemented in a
+ * future release.
+ */
+ sbp[0]->s_state = cpu_to_le16(le16_to_cpu(sbp[0]->s_state) &
+ ~NILFS_RESIZE_FS);
+ sbp[0]->s_dev_size = cpu_to_le64(newsize);
+ sbp[0]->s_nsegments = cpu_to_le64(nilfs->ns_nsegments);
+ if (sbp[1])
+ memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
+ ret = nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
+ }
+ up_write(&nilfs->ns_sem);
+
+ /*
+ * Reset the range of allocatable segments last. This order
+ * is important in the case of expansion because the secondary
+ * superblock must be protected from log write until migration
+ * completes.
+ */
+ if (!ret)
+ nilfs_sufile_set_alloc_range(nilfs->ns_sufile, 0, newnsegs - 1);
+out:
+ return ret;
+}
+
+static void nilfs_put_super(struct super_block *sb)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+
+ nilfs_detach_log_writer(sb);
+
+ if (!sb_rdonly(sb)) {
+ down_write(&nilfs->ns_sem);
+ nilfs_cleanup_super(sb);
+ up_write(&nilfs->ns_sem);
+ }
+
+ nilfs_sysfs_delete_device_group(nilfs);
+ iput(nilfs->ns_sufile);
+ iput(nilfs->ns_cpfile);
+ iput(nilfs->ns_dat);
+
+ destroy_nilfs(nilfs);
+ sb->s_fs_info = NULL;
+}
+
+static int nilfs_sync_fs(struct super_block *sb, int wait)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_super_block **sbp;
+ int err = 0;
+
+ /* This function is called when super block should be written back */
+ if (wait)
+ err = nilfs_construct_segment(sb);
+
+ down_write(&nilfs->ns_sem);
+ if (nilfs_sb_dirty(nilfs)) {
+ sbp = nilfs_prepare_super(sb, nilfs_sb_will_flip(nilfs));
+ if (likely(sbp)) {
+ nilfs_set_log_cursor(sbp[0], nilfs);
+ nilfs_commit_super(sb, NILFS_SB_COMMIT);
+ }
+ }
+ up_write(&nilfs->ns_sem);
+
+ if (!err)
+ err = nilfs_flush_device(nilfs);
+
+ return err;
+}
+
+int nilfs_attach_checkpoint(struct super_block *sb, __u64 cno, int curr_mnt,
+ struct nilfs_root **rootp)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_root *root;
+ struct nilfs_checkpoint *raw_cp;
+ struct buffer_head *bh_cp;
+ int err = -ENOMEM;
+
+ root = nilfs_find_or_create_root(
+ nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno);
+ if (!root)
+ return err;
+
+ if (root->ifile)
+ goto reuse; /* already attached checkpoint */
+
+ down_read(&nilfs->ns_segctor_sem);
+ err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
+ &bh_cp);
+ up_read(&nilfs->ns_segctor_sem);
+ if (unlikely(err)) {
+ if (err == -ENOENT || err == -EINVAL) {
+ nilfs_err(sb,
+ "Invalid checkpoint (checkpoint number=%llu)",
+ (unsigned long long)cno);
+ err = -EINVAL;
+ }
+ goto failed;
+ }
+
+ err = nilfs_ifile_read(sb, root, nilfs->ns_inode_size,
+ &raw_cp->cp_ifile_inode, &root->ifile);
+ if (err)
+ goto failed_bh;
+
+ atomic64_set(&root->inodes_count,
+ le64_to_cpu(raw_cp->cp_inodes_count));
+ atomic64_set(&root->blocks_count,
+ le64_to_cpu(raw_cp->cp_blocks_count));
+
+ nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
+
+ reuse:
+ *rootp = root;
+ return 0;
+
+ failed_bh:
+ nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
+ failed:
+ nilfs_put_root(root);
+
+ return err;
+}
+
+static int nilfs_freeze(struct super_block *sb)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ int err;
+
+ if (sb_rdonly(sb))
+ return 0;
+
+ /* Mark super block clean */
+ down_write(&nilfs->ns_sem);
+ err = nilfs_cleanup_super(sb);
+ up_write(&nilfs->ns_sem);
+ return err;
+}
+
+static int nilfs_unfreeze(struct super_block *sb)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+
+ if (sb_rdonly(sb))
+ return 0;
+
+ down_write(&nilfs->ns_sem);
+ nilfs_setup_super(sb, false);
+ up_write(&nilfs->ns_sem);
+ return 0;
+}
+
+static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct super_block *sb = dentry->d_sb;
+ struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root;
+ struct the_nilfs *nilfs = root->nilfs;
+ u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
+ unsigned long long blocks;
+ unsigned long overhead;
+ unsigned long nrsvblocks;
+ sector_t nfreeblocks;
+ u64 nmaxinodes, nfreeinodes;
+ int err;
+
+ /*
+ * Compute all of the segment blocks
+ *
+ * The blocks before first segment and after last segment
+ * are excluded.
+ */
+ blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments
+ - nilfs->ns_first_data_block;
+ nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment;
+
+ /*
+ * Compute the overhead
+ *
+ * When distributing meta data blocks outside segment structure,
+ * We must count them as the overhead.
+ */
+ overhead = 0;
+
+ err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
+ if (unlikely(err))
+ return err;
+
+ err = nilfs_ifile_count_free_inodes(root->ifile,
+ &nmaxinodes, &nfreeinodes);
+ if (unlikely(err)) {
+ nilfs_warn(sb, "failed to count free inodes: err=%d", err);
+ if (err == -ERANGE) {
+ /*
+ * If nilfs_palloc_count_max_entries() returns
+ * -ERANGE error code then we simply treat
+ * curent inodes count as maximum possible and
+ * zero as free inodes value.
+ */
+ nmaxinodes = atomic64_read(&root->inodes_count);
+ nfreeinodes = 0;
+ err = 0;
+ } else
+ return err;
+ }
+
+ buf->f_type = NILFS_SUPER_MAGIC;
+ buf->f_bsize = sb->s_blocksize;
+ buf->f_blocks = blocks - overhead;
+ buf->f_bfree = nfreeblocks;
+ buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
+ (buf->f_bfree - nrsvblocks) : 0;
+ buf->f_files = nmaxinodes;
+ buf->f_ffree = nfreeinodes;
+ buf->f_namelen = NILFS_NAME_LEN;
+ buf->f_fsid = u64_to_fsid(id);
+
+ return 0;
+}
+
+static int nilfs_show_options(struct seq_file *seq, struct dentry *dentry)
+{
+ struct super_block *sb = dentry->d_sb;
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root;
+
+ if (!nilfs_test_opt(nilfs, BARRIER))
+ seq_puts(seq, ",nobarrier");
+ if (root->cno != NILFS_CPTREE_CURRENT_CNO)
+ seq_printf(seq, ",cp=%llu", (unsigned long long)root->cno);
+ if (nilfs_test_opt(nilfs, ERRORS_PANIC))
+ seq_puts(seq, ",errors=panic");
+ if (nilfs_test_opt(nilfs, ERRORS_CONT))
+ seq_puts(seq, ",errors=continue");
+ if (nilfs_test_opt(nilfs, STRICT_ORDER))
+ seq_puts(seq, ",order=strict");
+ if (nilfs_test_opt(nilfs, NORECOVERY))
+ seq_puts(seq, ",norecovery");
+ if (nilfs_test_opt(nilfs, DISCARD))
+ seq_puts(seq, ",discard");
+
+ return 0;
+}
+
+static const struct super_operations nilfs_sops = {
+ .alloc_inode = nilfs_alloc_inode,
+ .free_inode = nilfs_free_inode,
+ .dirty_inode = nilfs_dirty_inode,
+ .evict_inode = nilfs_evict_inode,
+ .put_super = nilfs_put_super,
+ .sync_fs = nilfs_sync_fs,
+ .freeze_fs = nilfs_freeze,
+ .unfreeze_fs = nilfs_unfreeze,
+ .statfs = nilfs_statfs,
+ .remount_fs = nilfs_remount,
+ .show_options = nilfs_show_options
+};
+
+enum {
+ Opt_err_cont, Opt_err_panic, Opt_err_ro,
+ Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,
+ Opt_discard, Opt_nodiscard, Opt_err,
+};
+
+static match_table_t tokens = {
+ {Opt_err_cont, "errors=continue"},
+ {Opt_err_panic, "errors=panic"},
+ {Opt_err_ro, "errors=remount-ro"},
+ {Opt_barrier, "barrier"},
+ {Opt_nobarrier, "nobarrier"},
+ {Opt_snapshot, "cp=%u"},
+ {Opt_order, "order=%s"},
+ {Opt_norecovery, "norecovery"},
+ {Opt_discard, "discard"},
+ {Opt_nodiscard, "nodiscard"},
+ {Opt_err, NULL}
+};
+
+static int parse_options(char *options, struct super_block *sb, int is_remount)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ char *p;
+ substring_t args[MAX_OPT_ARGS];
+
+ if (!options)
+ return 1;
+
+ while ((p = strsep(&options, ",")) != NULL) {
+ int token;
+
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_barrier:
+ nilfs_set_opt(nilfs, BARRIER);
+ break;
+ case Opt_nobarrier:
+ nilfs_clear_opt(nilfs, BARRIER);
+ break;
+ case Opt_order:
+ if (strcmp(args[0].from, "relaxed") == 0)
+ /* Ordered data semantics */
+ nilfs_clear_opt(nilfs, STRICT_ORDER);
+ else if (strcmp(args[0].from, "strict") == 0)
+ /* Strict in-order semantics */
+ nilfs_set_opt(nilfs, STRICT_ORDER);
+ else
+ return 0;
+ break;
+ case Opt_err_panic:
+ nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_PANIC);
+ break;
+ case Opt_err_ro:
+ nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_RO);
+ break;
+ case Opt_err_cont:
+ nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_CONT);
+ break;
+ case Opt_snapshot:
+ if (is_remount) {
+ nilfs_err(sb,
+ "\"%s\" option is invalid for remount",
+ p);
+ return 0;
+ }
+ break;
+ case Opt_norecovery:
+ nilfs_set_opt(nilfs, NORECOVERY);
+ break;
+ case Opt_discard:
+ nilfs_set_opt(nilfs, DISCARD);
+ break;
+ case Opt_nodiscard:
+ nilfs_clear_opt(nilfs, DISCARD);
+ break;
+ default:
+ nilfs_err(sb, "unrecognized mount option \"%s\"", p);
+ return 0;
+ }
+ }
+ return 1;
+}
+
+static inline void
+nilfs_set_default_options(struct super_block *sb,
+ struct nilfs_super_block *sbp)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+
+ nilfs->ns_mount_opt =
+ NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER;
+}
+
+static int nilfs_setup_super(struct super_block *sb, int is_mount)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_super_block **sbp;
+ int max_mnt_count;
+ int mnt_count;
+
+ /* nilfs->ns_sem must be locked by the caller. */
+ sbp = nilfs_prepare_super(sb, 0);
+ if (!sbp)
+ return -EIO;
+
+ if (!is_mount)
+ goto skip_mount_setup;
+
+ max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count);
+ mnt_count = le16_to_cpu(sbp[0]->s_mnt_count);
+
+ if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
+ nilfs_warn(sb, "mounting fs with errors");
+#if 0
+ } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
+ nilfs_warn(sb, "maximal mount count reached");
+#endif
+ }
+ if (!max_mnt_count)
+ sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
+
+ sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1);
+ sbp[0]->s_mtime = cpu_to_le64(ktime_get_real_seconds());
+
+skip_mount_setup:
+ sbp[0]->s_state =
+ cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
+ /* synchronize sbp[1] with sbp[0] */
+ if (sbp[1])
+ memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
+ return nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
+}
+
+struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
+ u64 pos, int blocksize,
+ struct buffer_head **pbh)
+{
+ unsigned long long sb_index = pos;
+ unsigned long offset;
+
+ offset = do_div(sb_index, blocksize);
+ *pbh = sb_bread(sb, sb_index);
+ if (!*pbh)
+ return NULL;
+ return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
+}
+
+int nilfs_store_magic_and_option(struct super_block *sb,
+ struct nilfs_super_block *sbp,
+ char *data)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+
+ sb->s_magic = le16_to_cpu(sbp->s_magic);
+
+ /* FS independent flags */
+#ifdef NILFS_ATIME_DISABLE
+ sb->s_flags |= SB_NOATIME;
+#endif
+
+ nilfs_set_default_options(sb, sbp);
+
+ nilfs->ns_resuid = le16_to_cpu(sbp->s_def_resuid);
+ nilfs->ns_resgid = le16_to_cpu(sbp->s_def_resgid);
+ nilfs->ns_interval = le32_to_cpu(sbp->s_c_interval);
+ nilfs->ns_watermark = le32_to_cpu(sbp->s_c_block_max);
+
+ return !parse_options(data, sb, 0) ? -EINVAL : 0;
+}
+
+int nilfs_check_feature_compatibility(struct super_block *sb,
+ struct nilfs_super_block *sbp)
+{
+ __u64 features;
+
+ features = le64_to_cpu(sbp->s_feature_incompat) &
+ ~NILFS_FEATURE_INCOMPAT_SUPP;
+ if (features) {
+ nilfs_err(sb,
+ "couldn't mount because of unsupported optional features (%llx)",
+ (unsigned long long)features);
+ return -EINVAL;
+ }
+ features = le64_to_cpu(sbp->s_feature_compat_ro) &
+ ~NILFS_FEATURE_COMPAT_RO_SUPP;
+ if (!sb_rdonly(sb) && features) {
+ nilfs_err(sb,
+ "couldn't mount RDWR because of unsupported optional features (%llx)",
+ (unsigned long long)features);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int nilfs_get_root_dentry(struct super_block *sb,
+ struct nilfs_root *root,
+ struct dentry **root_dentry)
+{
+ struct inode *inode;
+ struct dentry *dentry;
+ int ret = 0;
+
+ inode = nilfs_iget(sb, root, NILFS_ROOT_INO);
+ if (IS_ERR(inode)) {
+ ret = PTR_ERR(inode);
+ nilfs_err(sb, "error %d getting root inode", ret);
+ goto out;
+ }
+ if (!S_ISDIR(inode->i_mode) || !inode->i_blocks || !inode->i_size) {
+ iput(inode);
+ nilfs_err(sb, "corrupt root inode");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (root->cno == NILFS_CPTREE_CURRENT_CNO) {
+ dentry = d_find_alias(inode);
+ if (!dentry) {
+ dentry = d_make_root(inode);
+ if (!dentry) {
+ ret = -ENOMEM;
+ goto failed_dentry;
+ }
+ } else {
+ iput(inode);
+ }
+ } else {
+ dentry = d_obtain_root(inode);
+ if (IS_ERR(dentry)) {
+ ret = PTR_ERR(dentry);
+ goto failed_dentry;
+ }
+ }
+ *root_dentry = dentry;
+ out:
+ return ret;
+
+ failed_dentry:
+ nilfs_err(sb, "error %d getting root dentry", ret);
+ goto out;
+}
+
+static int nilfs_attach_snapshot(struct super_block *s, __u64 cno,
+ struct dentry **root_dentry)
+{
+ struct the_nilfs *nilfs = s->s_fs_info;
+ struct nilfs_root *root;
+ int ret;
+
+ mutex_lock(&nilfs->ns_snapshot_mount_mutex);
+
+ down_read(&nilfs->ns_segctor_sem);
+ ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno);
+ up_read(&nilfs->ns_segctor_sem);
+ if (ret < 0) {
+ ret = (ret == -ENOENT) ? -EINVAL : ret;
+ goto out;
+ } else if (!ret) {
+ nilfs_err(s,
+ "The specified checkpoint is not a snapshot (checkpoint number=%llu)",
+ (unsigned long long)cno);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = nilfs_attach_checkpoint(s, cno, false, &root);
+ if (ret) {
+ nilfs_err(s,
+ "error %d while loading snapshot (checkpoint number=%llu)",
+ ret, (unsigned long long)cno);
+ goto out;
+ }
+ ret = nilfs_get_root_dentry(s, root, root_dentry);
+ nilfs_put_root(root);
+ out:
+ mutex_unlock(&nilfs->ns_snapshot_mount_mutex);
+ return ret;
+}
+
+/**
+ * nilfs_tree_is_busy() - try to shrink dentries of a checkpoint
+ * @root_dentry: root dentry of the tree to be shrunk
+ *
+ * This function returns true if the tree was in-use.
+ */
+static bool nilfs_tree_is_busy(struct dentry *root_dentry)
+{
+ shrink_dcache_parent(root_dentry);
+ return d_count(root_dentry) > 1;
+}
+
+int nilfs_checkpoint_is_mounted(struct super_block *sb, __u64 cno)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_root *root;
+ struct inode *inode;
+ struct dentry *dentry;
+ int ret;
+
+ if (cno > nilfs->ns_cno)
+ return false;
+
+ if (cno >= nilfs_last_cno(nilfs))
+ return true; /* protect recent checkpoints */
+
+ ret = false;
+ root = nilfs_lookup_root(nilfs, cno);
+ if (root) {
+ inode = nilfs_ilookup(sb, root, NILFS_ROOT_INO);
+ if (inode) {
+ dentry = d_find_alias(inode);
+ if (dentry) {
+ ret = nilfs_tree_is_busy(dentry);
+ dput(dentry);
+ }
+ iput(inode);
+ }
+ nilfs_put_root(root);
+ }
+ return ret;
+}
+
+/**
+ * nilfs_fill_super() - initialize a super block instance
+ * @sb: super_block
+ * @data: mount options
+ * @silent: silent mode flag
+ *
+ * This function is called exclusively by nilfs->ns_mount_mutex.
+ * So, the recovery process is protected from other simultaneous mounts.
+ */
+static int
+nilfs_fill_super(struct super_block *sb, void *data, int silent)
+{
+ struct the_nilfs *nilfs;
+ struct nilfs_root *fsroot;
+ __u64 cno;
+ int err;
+
+ nilfs = alloc_nilfs(sb);
+ if (!nilfs)
+ return -ENOMEM;
+
+ sb->s_fs_info = nilfs;
+
+ err = init_nilfs(nilfs, sb, (char *)data);
+ if (err)
+ goto failed_nilfs;
+
+ sb->s_op = &nilfs_sops;
+ sb->s_export_op = &nilfs_export_ops;
+ sb->s_root = NULL;
+ sb->s_time_gran = 1;
+ sb->s_max_links = NILFS_LINK_MAX;
+
+ sb->s_bdi = bdi_get(sb->s_bdev->bd_disk->bdi);
+
+ err = load_nilfs(nilfs, sb);
+ if (err)
+ goto failed_nilfs;
+
+ cno = nilfs_last_cno(nilfs);
+ err = nilfs_attach_checkpoint(sb, cno, true, &fsroot);
+ if (err) {
+ nilfs_err(sb,
+ "error %d while loading last checkpoint (checkpoint number=%llu)",
+ err, (unsigned long long)cno);
+ goto failed_unload;
+ }
+
+ if (!sb_rdonly(sb)) {
+ err = nilfs_attach_log_writer(sb, fsroot);
+ if (err)
+ goto failed_checkpoint;
+ }
+
+ err = nilfs_get_root_dentry(sb, fsroot, &sb->s_root);
+ if (err)
+ goto failed_segctor;
+
+ nilfs_put_root(fsroot);
+
+ if (!sb_rdonly(sb)) {
+ down_write(&nilfs->ns_sem);
+ nilfs_setup_super(sb, true);
+ up_write(&nilfs->ns_sem);
+ }
+
+ return 0;
+
+ failed_segctor:
+ nilfs_detach_log_writer(sb);
+
+ failed_checkpoint:
+ nilfs_put_root(fsroot);
+
+ failed_unload:
+ nilfs_sysfs_delete_device_group(nilfs);
+ iput(nilfs->ns_sufile);
+ iput(nilfs->ns_cpfile);
+ iput(nilfs->ns_dat);
+
+ failed_nilfs:
+ destroy_nilfs(nilfs);
+ return err;
+}
+
+static int nilfs_remount(struct super_block *sb, int *flags, char *data)
+{
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ unsigned long old_sb_flags;
+ unsigned long old_mount_opt;
+ int err;
+
+ sync_filesystem(sb);
+ old_sb_flags = sb->s_flags;
+ old_mount_opt = nilfs->ns_mount_opt;
+
+ if (!parse_options(data, sb, 1)) {
+ err = -EINVAL;
+ goto restore_opts;
+ }
+ sb->s_flags = (sb->s_flags & ~SB_POSIXACL);
+
+ err = -EINVAL;
+
+ if (!nilfs_valid_fs(nilfs)) {
+ nilfs_warn(sb,
+ "couldn't remount because the filesystem is in an incomplete recovery state");
+ goto restore_opts;
+ }
+
+ if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
+ goto out;
+ if (*flags & SB_RDONLY) {
+ sb->s_flags |= SB_RDONLY;
+
+ /*
+ * Remounting a valid RW partition RDONLY, so set
+ * the RDONLY flag and then mark the partition as valid again.
+ */
+ down_write(&nilfs->ns_sem);
+ nilfs_cleanup_super(sb);
+ up_write(&nilfs->ns_sem);
+ } else {
+ __u64 features;
+ struct nilfs_root *root;
+
+ /*
+ * Mounting a RDONLY partition read-write, so reread and
+ * store the current valid flag. (It may have been changed
+ * by fsck since we originally mounted the partition.)
+ */
+ down_read(&nilfs->ns_sem);
+ features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) &
+ ~NILFS_FEATURE_COMPAT_RO_SUPP;
+ up_read(&nilfs->ns_sem);
+ if (features) {
+ nilfs_warn(sb,
+ "couldn't remount RDWR because of unsupported optional features (%llx)",
+ (unsigned long long)features);
+ err = -EROFS;
+ goto restore_opts;
+ }
+
+ sb->s_flags &= ~SB_RDONLY;
+
+ root = NILFS_I(d_inode(sb->s_root))->i_root;
+ err = nilfs_attach_log_writer(sb, root);
+ if (err)
+ goto restore_opts;
+
+ down_write(&nilfs->ns_sem);
+ nilfs_setup_super(sb, true);
+ up_write(&nilfs->ns_sem);
+ }
+ out:
+ return 0;
+
+ restore_opts:
+ sb->s_flags = old_sb_flags;
+ nilfs->ns_mount_opt = old_mount_opt;
+ return err;
+}
+
+struct nilfs_super_data {
+ struct block_device *bdev;
+ __u64 cno;
+ int flags;
+};
+
+static int nilfs_parse_snapshot_option(const char *option,
+ const substring_t *arg,
+ struct nilfs_super_data *sd)
+{
+ unsigned long long val;
+ const char *msg = NULL;
+ int err;
+
+ if (!(sd->flags & SB_RDONLY)) {
+ msg = "read-only option is not specified";
+ goto parse_error;
+ }
+
+ err = kstrtoull(arg->from, 0, &val);
+ if (err) {
+ if (err == -ERANGE)
+ msg = "too large checkpoint number";
+ else
+ msg = "malformed argument";
+ goto parse_error;
+ } else if (val == 0) {
+ msg = "invalid checkpoint number 0";
+ goto parse_error;
+ }
+ sd->cno = val;
+ return 0;
+
+parse_error:
+ nilfs_err(NULL, "invalid option \"%s\": %s", option, msg);
+ return 1;
+}
+
+/**
+ * nilfs_identify - pre-read mount options needed to identify mount instance
+ * @data: mount options
+ * @sd: nilfs_super_data
+ */
+static int nilfs_identify(char *data, struct nilfs_super_data *sd)
+{
+ char *p, *options = data;
+ substring_t args[MAX_OPT_ARGS];
+ int token;
+ int ret = 0;
+
+ do {
+ p = strsep(&options, ",");
+ if (p != NULL && *p) {
+ token = match_token(p, tokens, args);
+ if (token == Opt_snapshot)
+ ret = nilfs_parse_snapshot_option(p, &args[0],
+ sd);
+ }
+ if (!options)
+ break;
+ BUG_ON(options == data);
+ *(options - 1) = ',';
+ } while (!ret);
+ return ret;
+}
+
+static int nilfs_set_bdev_super(struct super_block *s, void *data)
+{
+ s->s_bdev = data;
+ s->s_dev = s->s_bdev->bd_dev;
+ return 0;
+}
+
+static int nilfs_test_bdev_super(struct super_block *s, void *data)
+{
+ return (void *)s->s_bdev == data;
+}
+
+static struct dentry *
+nilfs_mount(struct file_system_type *fs_type, int flags,
+ const char *dev_name, void *data)
+{
+ struct nilfs_super_data sd;
+ struct super_block *s;
+ fmode_t mode = FMODE_READ | FMODE_EXCL;
+ struct dentry *root_dentry;
+ int err, s_new = false;
+
+ if (!(flags & SB_RDONLY))
+ mode |= FMODE_WRITE;
+
+ sd.bdev = blkdev_get_by_path(dev_name, mode, fs_type);
+ if (IS_ERR(sd.bdev))
+ return ERR_CAST(sd.bdev);
+
+ sd.cno = 0;
+ sd.flags = flags;
+ if (nilfs_identify((char *)data, &sd)) {
+ err = -EINVAL;
+ goto failed;
+ }
+
+ /*
+ * once the super is inserted into the list by sget, s_umount
+ * will protect the lockfs code from trying to start a snapshot
+ * while we are mounting
+ */
+ mutex_lock(&sd.bdev->bd_fsfreeze_mutex);
+ if (sd.bdev->bd_fsfreeze_count > 0) {
+ mutex_unlock(&sd.bdev->bd_fsfreeze_mutex);
+ err = -EBUSY;
+ goto failed;
+ }
+ s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, flags,
+ sd.bdev);
+ mutex_unlock(&sd.bdev->bd_fsfreeze_mutex);
+ if (IS_ERR(s)) {
+ err = PTR_ERR(s);
+ goto failed;
+ }
+
+ if (!s->s_root) {
+ s_new = true;
+
+ /* New superblock instance created */
+ s->s_mode = mode;
+ snprintf(s->s_id, sizeof(s->s_id), "%pg", sd.bdev);
+ sb_set_blocksize(s, block_size(sd.bdev));
+
+ err = nilfs_fill_super(s, data, flags & SB_SILENT ? 1 : 0);
+ if (err)
+ goto failed_super;
+
+ s->s_flags |= SB_ACTIVE;
+ } else if (!sd.cno) {
+ if (nilfs_tree_is_busy(s->s_root)) {
+ if ((flags ^ s->s_flags) & SB_RDONLY) {
+ nilfs_err(s,
+ "the device already has a %s mount.",
+ sb_rdonly(s) ? "read-only" : "read/write");
+ err = -EBUSY;
+ goto failed_super;
+ }
+ } else {
+ /*
+ * Try remount to setup mount states if the current
+ * tree is not mounted and only snapshots use this sb.
+ */
+ err = nilfs_remount(s, &flags, data);
+ if (err)
+ goto failed_super;
+ }
+ }
+
+ if (sd.cno) {
+ err = nilfs_attach_snapshot(s, sd.cno, &root_dentry);
+ if (err)
+ goto failed_super;
+ } else {
+ root_dentry = dget(s->s_root);
+ }
+
+ if (!s_new)
+ blkdev_put(sd.bdev, mode);
+
+ return root_dentry;
+
+ failed_super:
+ deactivate_locked_super(s);
+
+ failed:
+ if (!s_new)
+ blkdev_put(sd.bdev, mode);
+ return ERR_PTR(err);
+}
+
+struct file_system_type nilfs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "nilfs2",
+ .mount = nilfs_mount,
+ .kill_sb = kill_block_super,
+ .fs_flags = FS_REQUIRES_DEV,
+};
+MODULE_ALIAS_FS("nilfs2");
+
+static void nilfs_inode_init_once(void *obj)
+{
+ struct nilfs_inode_info *ii = obj;
+
+ INIT_LIST_HEAD(&ii->i_dirty);
+#ifdef CONFIG_NILFS_XATTR
+ init_rwsem(&ii->xattr_sem);
+#endif
+ inode_init_once(&ii->vfs_inode);
+}
+
+static void nilfs_segbuf_init_once(void *obj)
+{
+ memset(obj, 0, sizeof(struct nilfs_segment_buffer));
+}
+
+static void nilfs_destroy_cachep(void)
+{
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy cache.
+ */
+ rcu_barrier();
+
+ kmem_cache_destroy(nilfs_inode_cachep);
+ kmem_cache_destroy(nilfs_transaction_cachep);
+ kmem_cache_destroy(nilfs_segbuf_cachep);
+ kmem_cache_destroy(nilfs_btree_path_cache);
+}
+
+static int __init nilfs_init_cachep(void)
+{
+ nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
+ sizeof(struct nilfs_inode_info), 0,
+ SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT,
+ nilfs_inode_init_once);
+ if (!nilfs_inode_cachep)
+ goto fail;
+
+ nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache",
+ sizeof(struct nilfs_transaction_info), 0,
+ SLAB_RECLAIM_ACCOUNT, NULL);
+ if (!nilfs_transaction_cachep)
+ goto fail;
+
+ nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache",
+ sizeof(struct nilfs_segment_buffer), 0,
+ SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once);
+ if (!nilfs_segbuf_cachep)
+ goto fail;
+
+ nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache",
+ sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX,
+ 0, 0, NULL);
+ if (!nilfs_btree_path_cache)
+ goto fail;
+
+ return 0;
+
+fail:
+ nilfs_destroy_cachep();
+ return -ENOMEM;
+}
+
+static int __init init_nilfs_fs(void)
+{
+ int err;
+
+ err = nilfs_init_cachep();
+ if (err)
+ goto fail;
+
+ err = nilfs_sysfs_init();
+ if (err)
+ goto free_cachep;
+
+ err = register_filesystem(&nilfs_fs_type);
+ if (err)
+ goto deinit_sysfs_entry;
+
+ printk(KERN_INFO "NILFS version 2 loaded\n");
+ return 0;
+
+deinit_sysfs_entry:
+ nilfs_sysfs_exit();
+free_cachep:
+ nilfs_destroy_cachep();
+fail:
+ return err;
+}
+
+static void __exit exit_nilfs_fs(void)
+{
+ nilfs_destroy_cachep();
+ nilfs_sysfs_exit();
+ unregister_filesystem(&nilfs_fs_type);
+}
+
+module_init(init_nilfs_fs)
+module_exit(exit_nilfs_fs)
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-08 12:44:03 +0000