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-rw-r--r--fs/zonefs/super.c1252
1 files changed, 1252 insertions, 0 deletions
diff --git a/fs/zonefs/super.c b/fs/zonefs/super.c
new file mode 100644
index 000000000..270ded209
--- /dev/null
+++ b/fs/zonefs/super.c
@@ -0,0 +1,1252 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Simple file system for zoned block devices exposing zones as files.
+ *
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ */
+#include <linux/module.h>
+#include <linux/pagemap.h>
+#include <linux/magic.h>
+#include <linux/iomap.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/blkdev.h>
+#include <linux/statfs.h>
+#include <linux/writeback.h>
+#include <linux/quotaops.h>
+#include <linux/seq_file.h>
+#include <linux/parser.h>
+#include <linux/uio.h>
+#include <linux/mman.h>
+#include <linux/sched/mm.h>
+#include <linux/crc32.h>
+#include <linux/task_io_accounting_ops.h>
+
+#include "zonefs.h"
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
+
+/*
+ * Get the name of a zone group directory.
+ */
+static const char *zonefs_zgroup_name(enum zonefs_ztype ztype)
+{
+ switch (ztype) {
+ case ZONEFS_ZTYPE_CNV:
+ return "cnv";
+ case ZONEFS_ZTYPE_SEQ:
+ return "seq";
+ default:
+ WARN_ON_ONCE(1);
+ return "???";
+ }
+}
+
+/*
+ * Manage the active zone count.
+ */
+static void zonefs_account_active(struct super_block *sb,
+ struct zonefs_zone *z)
+{
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+
+ if (zonefs_zone_is_cnv(z))
+ return;
+
+ /*
+ * For zones that transitioned to the offline or readonly condition,
+ * we only need to clear the active state.
+ */
+ if (z->z_flags & (ZONEFS_ZONE_OFFLINE | ZONEFS_ZONE_READONLY))
+ goto out;
+
+ /*
+ * If the zone is active, that is, if it is explicitly open or
+ * partially written, check if it was already accounted as active.
+ */
+ if ((z->z_flags & ZONEFS_ZONE_OPEN) ||
+ (z->z_wpoffset > 0 && z->z_wpoffset < z->z_capacity)) {
+ if (!(z->z_flags & ZONEFS_ZONE_ACTIVE)) {
+ z->z_flags |= ZONEFS_ZONE_ACTIVE;
+ atomic_inc(&sbi->s_active_seq_files);
+ }
+ return;
+ }
+
+out:
+ /* The zone is not active. If it was, update the active count */
+ if (z->z_flags & ZONEFS_ZONE_ACTIVE) {
+ z->z_flags &= ~ZONEFS_ZONE_ACTIVE;
+ atomic_dec(&sbi->s_active_seq_files);
+ }
+}
+
+/*
+ * Manage the active zone count. Called with zi->i_truncate_mutex held.
+ */
+void zonefs_inode_account_active(struct inode *inode)
+{
+ lockdep_assert_held(&ZONEFS_I(inode)->i_truncate_mutex);
+
+ return zonefs_account_active(inode->i_sb, zonefs_inode_zone(inode));
+}
+
+/*
+ * Execute a zone management operation.
+ */
+static int zonefs_zone_mgmt(struct super_block *sb,
+ struct zonefs_zone *z, enum req_op op)
+{
+ int ret;
+
+ /*
+ * With ZNS drives, closing an explicitly open zone that has not been
+ * written will change the zone state to "closed", that is, the zone
+ * will remain active. Since this can then cause failure of explicit
+ * open operation on other zones if the drive active zone resources
+ * are exceeded, make sure that the zone does not remain active by
+ * resetting it.
+ */
+ if (op == REQ_OP_ZONE_CLOSE && !z->z_wpoffset)
+ op = REQ_OP_ZONE_RESET;
+
+ trace_zonefs_zone_mgmt(sb, z, op);
+ ret = blkdev_zone_mgmt(sb->s_bdev, op, z->z_sector,
+ z->z_size >> SECTOR_SHIFT, GFP_NOFS);
+ if (ret) {
+ zonefs_err(sb,
+ "Zone management operation %s at %llu failed %d\n",
+ blk_op_str(op), z->z_sector, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+int zonefs_inode_zone_mgmt(struct inode *inode, enum req_op op)
+{
+ lockdep_assert_held(&ZONEFS_I(inode)->i_truncate_mutex);
+
+ return zonefs_zone_mgmt(inode->i_sb, zonefs_inode_zone(inode), op);
+}
+
+void zonefs_i_size_write(struct inode *inode, loff_t isize)
+{
+ struct zonefs_zone *z = zonefs_inode_zone(inode);
+
+ i_size_write(inode, isize);
+
+ /*
+ * A full zone is no longer open/active and does not need
+ * explicit closing.
+ */
+ if (isize >= z->z_capacity) {
+ struct zonefs_sb_info *sbi = ZONEFS_SB(inode->i_sb);
+
+ if (z->z_flags & ZONEFS_ZONE_ACTIVE)
+ atomic_dec(&sbi->s_active_seq_files);
+ z->z_flags &= ~(ZONEFS_ZONE_OPEN | ZONEFS_ZONE_ACTIVE);
+ }
+}
+
+void zonefs_update_stats(struct inode *inode, loff_t new_isize)
+{
+ struct super_block *sb = inode->i_sb;
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+ loff_t old_isize = i_size_read(inode);
+ loff_t nr_blocks;
+
+ if (new_isize == old_isize)
+ return;
+
+ spin_lock(&sbi->s_lock);
+
+ /*
+ * This may be called for an update after an IO error.
+ * So beware of the values seen.
+ */
+ if (new_isize < old_isize) {
+ nr_blocks = (old_isize - new_isize) >> sb->s_blocksize_bits;
+ if (sbi->s_used_blocks > nr_blocks)
+ sbi->s_used_blocks -= nr_blocks;
+ else
+ sbi->s_used_blocks = 0;
+ } else {
+ sbi->s_used_blocks +=
+ (new_isize - old_isize) >> sb->s_blocksize_bits;
+ if (sbi->s_used_blocks > sbi->s_blocks)
+ sbi->s_used_blocks = sbi->s_blocks;
+ }
+
+ spin_unlock(&sbi->s_lock);
+}
+
+/*
+ * Check a zone condition. Return the amount of written (and still readable)
+ * data in the zone.
+ */
+static loff_t zonefs_check_zone_condition(struct super_block *sb,
+ struct zonefs_zone *z,
+ struct blk_zone *zone)
+{
+ switch (zone->cond) {
+ case BLK_ZONE_COND_OFFLINE:
+ zonefs_warn(sb, "Zone %llu: offline zone\n",
+ z->z_sector);
+ z->z_flags |= ZONEFS_ZONE_OFFLINE;
+ return 0;
+ case BLK_ZONE_COND_READONLY:
+ /*
+ * The write pointer of read-only zones is invalid, so we cannot
+ * determine the zone wpoffset (inode size). We thus keep the
+ * zone wpoffset as is, which leads to an empty file
+ * (wpoffset == 0) on mount. For a runtime error, this keeps
+ * the inode size as it was when last updated so that the user
+ * can recover data.
+ */
+ zonefs_warn(sb, "Zone %llu: read-only zone\n",
+ z->z_sector);
+ z->z_flags |= ZONEFS_ZONE_READONLY;
+ if (zonefs_zone_is_cnv(z))
+ return z->z_capacity;
+ return z->z_wpoffset;
+ case BLK_ZONE_COND_FULL:
+ /* The write pointer of full zones is invalid. */
+ return z->z_capacity;
+ default:
+ if (zonefs_zone_is_cnv(z))
+ return z->z_capacity;
+ return (zone->wp - zone->start) << SECTOR_SHIFT;
+ }
+}
+
+/*
+ * Check a zone condition and adjust its inode access permissions for
+ * offline and readonly zones.
+ */
+static void zonefs_inode_update_mode(struct inode *inode)
+{
+ struct zonefs_zone *z = zonefs_inode_zone(inode);
+
+ if (z->z_flags & ZONEFS_ZONE_OFFLINE) {
+ /* Offline zones cannot be read nor written */
+ inode->i_flags |= S_IMMUTABLE;
+ inode->i_mode &= ~0777;
+ } else if (z->z_flags & ZONEFS_ZONE_READONLY) {
+ /* Readonly zones cannot be written */
+ inode->i_flags |= S_IMMUTABLE;
+ if (z->z_flags & ZONEFS_ZONE_INIT_MODE)
+ inode->i_mode &= ~0777;
+ else
+ inode->i_mode &= ~0222;
+ }
+
+ z->z_flags &= ~ZONEFS_ZONE_INIT_MODE;
+}
+
+struct zonefs_ioerr_data {
+ struct inode *inode;
+ bool write;
+};
+
+static int zonefs_io_error_cb(struct blk_zone *zone, unsigned int idx,
+ void *data)
+{
+ struct zonefs_ioerr_data *err = data;
+ struct inode *inode = err->inode;
+ struct zonefs_zone *z = zonefs_inode_zone(inode);
+ struct super_block *sb = inode->i_sb;
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+ loff_t isize, data_size;
+
+ /*
+ * Check the zone condition: if the zone is not "bad" (offline or
+ * read-only), read errors are simply signaled to the IO issuer as long
+ * as there is no inconsistency between the inode size and the amount of
+ * data writen in the zone (data_size).
+ */
+ data_size = zonefs_check_zone_condition(sb, z, zone);
+ isize = i_size_read(inode);
+ if (!(z->z_flags & (ZONEFS_ZONE_READONLY | ZONEFS_ZONE_OFFLINE)) &&
+ !err->write && isize == data_size)
+ return 0;
+
+ /*
+ * At this point, we detected either a bad zone or an inconsistency
+ * between the inode size and the amount of data written in the zone.
+ * For the latter case, the cause may be a write IO error or an external
+ * action on the device. Two error patterns exist:
+ * 1) The inode size is lower than the amount of data in the zone:
+ * a write operation partially failed and data was writen at the end
+ * of the file. This can happen in the case of a large direct IO
+ * needing several BIOs and/or write requests to be processed.
+ * 2) The inode size is larger than the amount of data in the zone:
+ * this can happen with a deferred write error with the use of the
+ * device side write cache after getting successful write IO
+ * completions. Other possibilities are (a) an external corruption,
+ * e.g. an application reset the zone directly, or (b) the device
+ * has a serious problem (e.g. firmware bug).
+ *
+ * In all cases, warn about inode size inconsistency and handle the
+ * IO error according to the zone condition and to the mount options.
+ */
+ if (zonefs_zone_is_seq(z) && isize != data_size)
+ zonefs_warn(sb,
+ "inode %lu: invalid size %lld (should be %lld)\n",
+ inode->i_ino, isize, data_size);
+
+ /*
+ * First handle bad zones signaled by hardware. The mount options
+ * errors=zone-ro and errors=zone-offline result in changing the
+ * zone condition to read-only and offline respectively, as if the
+ * condition was signaled by the hardware.
+ */
+ if ((z->z_flags & ZONEFS_ZONE_OFFLINE) ||
+ (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_ZOL)) {
+ zonefs_warn(sb, "inode %lu: read/write access disabled\n",
+ inode->i_ino);
+ if (!(z->z_flags & ZONEFS_ZONE_OFFLINE))
+ z->z_flags |= ZONEFS_ZONE_OFFLINE;
+ zonefs_inode_update_mode(inode);
+ data_size = 0;
+ } else if ((z->z_flags & ZONEFS_ZONE_READONLY) ||
+ (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_ZRO)) {
+ zonefs_warn(sb, "inode %lu: write access disabled\n",
+ inode->i_ino);
+ if (!(z->z_flags & ZONEFS_ZONE_READONLY))
+ z->z_flags |= ZONEFS_ZONE_READONLY;
+ zonefs_inode_update_mode(inode);
+ data_size = isize;
+ } else if (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_RO &&
+ data_size > isize) {
+ /* Do not expose garbage data */
+ data_size = isize;
+ }
+
+ /*
+ * If the filesystem is mounted with the explicit-open mount option, we
+ * need to clear the ZONEFS_ZONE_OPEN flag if the zone transitioned to
+ * the read-only or offline condition, to avoid attempting an explicit
+ * close of the zone when the inode file is closed.
+ */
+ if ((sbi->s_mount_opts & ZONEFS_MNTOPT_EXPLICIT_OPEN) &&
+ (z->z_flags & (ZONEFS_ZONE_READONLY | ZONEFS_ZONE_OFFLINE)))
+ z->z_flags &= ~ZONEFS_ZONE_OPEN;
+
+ /*
+ * If error=remount-ro was specified, any error result in remounting
+ * the volume as read-only.
+ */
+ if ((sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_RO) && !sb_rdonly(sb)) {
+ zonefs_warn(sb, "remounting filesystem read-only\n");
+ sb->s_flags |= SB_RDONLY;
+ }
+
+ /*
+ * Update block usage stats and the inode size to prevent access to
+ * invalid data.
+ */
+ zonefs_update_stats(inode, data_size);
+ zonefs_i_size_write(inode, data_size);
+ z->z_wpoffset = data_size;
+ zonefs_inode_account_active(inode);
+
+ return 0;
+}
+
+/*
+ * When an file IO error occurs, check the file zone to see if there is a change
+ * in the zone condition (e.g. offline or read-only). For a failed write to a
+ * sequential zone, the zone write pointer position must also be checked to
+ * eventually correct the file size and zonefs inode write pointer offset
+ * (which can be out of sync with the drive due to partial write failures).
+ */
+void __zonefs_io_error(struct inode *inode, bool write)
+{
+ struct zonefs_zone *z = zonefs_inode_zone(inode);
+ struct super_block *sb = inode->i_sb;
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+ unsigned int noio_flag;
+ unsigned int nr_zones = 1;
+ struct zonefs_ioerr_data err = {
+ .inode = inode,
+ .write = write,
+ };
+ int ret;
+
+ /*
+ * The only files that have more than one zone are conventional zone
+ * files with aggregated conventional zones, for which the inode zone
+ * size is always larger than the device zone size.
+ */
+ if (z->z_size > bdev_zone_sectors(sb->s_bdev))
+ nr_zones = z->z_size >>
+ (sbi->s_zone_sectors_shift + SECTOR_SHIFT);
+
+ /*
+ * Memory allocations in blkdev_report_zones() can trigger a memory
+ * reclaim which may in turn cause a recursion into zonefs as well as
+ * struct request allocations for the same device. The former case may
+ * end up in a deadlock on the inode truncate mutex, while the latter
+ * may prevent IO forward progress. Executing the report zones under
+ * the GFP_NOIO context avoids both problems.
+ */
+ noio_flag = memalloc_noio_save();
+ ret = blkdev_report_zones(sb->s_bdev, z->z_sector, nr_zones,
+ zonefs_io_error_cb, &err);
+ if (ret != nr_zones)
+ zonefs_err(sb, "Get inode %lu zone information failed %d\n",
+ inode->i_ino, ret);
+ memalloc_noio_restore(noio_flag);
+}
+
+static struct kmem_cache *zonefs_inode_cachep;
+
+static struct inode *zonefs_alloc_inode(struct super_block *sb)
+{
+ struct zonefs_inode_info *zi;
+
+ zi = alloc_inode_sb(sb, zonefs_inode_cachep, GFP_KERNEL);
+ if (!zi)
+ return NULL;
+
+ inode_init_once(&zi->i_vnode);
+ mutex_init(&zi->i_truncate_mutex);
+ zi->i_wr_refcnt = 0;
+
+ return &zi->i_vnode;
+}
+
+static void zonefs_free_inode(struct inode *inode)
+{
+ kmem_cache_free(zonefs_inode_cachep, ZONEFS_I(inode));
+}
+
+/*
+ * File system stat.
+ */
+static int zonefs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct super_block *sb = dentry->d_sb;
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+ enum zonefs_ztype t;
+
+ buf->f_type = ZONEFS_MAGIC;
+ buf->f_bsize = sb->s_blocksize;
+ buf->f_namelen = ZONEFS_NAME_MAX;
+
+ spin_lock(&sbi->s_lock);
+
+ buf->f_blocks = sbi->s_blocks;
+ if (WARN_ON(sbi->s_used_blocks > sbi->s_blocks))
+ buf->f_bfree = 0;
+ else
+ buf->f_bfree = buf->f_blocks - sbi->s_used_blocks;
+ buf->f_bavail = buf->f_bfree;
+
+ for (t = 0; t < ZONEFS_ZTYPE_MAX; t++) {
+ if (sbi->s_zgroup[t].g_nr_zones)
+ buf->f_files += sbi->s_zgroup[t].g_nr_zones + 1;
+ }
+ buf->f_ffree = 0;
+
+ spin_unlock(&sbi->s_lock);
+
+ buf->f_fsid = uuid_to_fsid(sbi->s_uuid.b);
+
+ return 0;
+}
+
+enum {
+ Opt_errors_ro, Opt_errors_zro, Opt_errors_zol, Opt_errors_repair,
+ Opt_explicit_open, Opt_err,
+};
+
+static const match_table_t tokens = {
+ { Opt_errors_ro, "errors=remount-ro"},
+ { Opt_errors_zro, "errors=zone-ro"},
+ { Opt_errors_zol, "errors=zone-offline"},
+ { Opt_errors_repair, "errors=repair"},
+ { Opt_explicit_open, "explicit-open" },
+ { Opt_err, NULL}
+};
+
+static int zonefs_parse_options(struct super_block *sb, char *options)
+{
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+ substring_t args[MAX_OPT_ARGS];
+ char *p;
+
+ if (!options)
+ return 0;
+
+ while ((p = strsep(&options, ",")) != NULL) {
+ int token;
+
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_errors_ro:
+ sbi->s_mount_opts &= ~ZONEFS_MNTOPT_ERRORS_MASK;
+ sbi->s_mount_opts |= ZONEFS_MNTOPT_ERRORS_RO;
+ break;
+ case Opt_errors_zro:
+ sbi->s_mount_opts &= ~ZONEFS_MNTOPT_ERRORS_MASK;
+ sbi->s_mount_opts |= ZONEFS_MNTOPT_ERRORS_ZRO;
+ break;
+ case Opt_errors_zol:
+ sbi->s_mount_opts &= ~ZONEFS_MNTOPT_ERRORS_MASK;
+ sbi->s_mount_opts |= ZONEFS_MNTOPT_ERRORS_ZOL;
+ break;
+ case Opt_errors_repair:
+ sbi->s_mount_opts &= ~ZONEFS_MNTOPT_ERRORS_MASK;
+ sbi->s_mount_opts |= ZONEFS_MNTOPT_ERRORS_REPAIR;
+ break;
+ case Opt_explicit_open:
+ sbi->s_mount_opts |= ZONEFS_MNTOPT_EXPLICIT_OPEN;
+ break;
+ default:
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+static int zonefs_show_options(struct seq_file *seq, struct dentry *root)
+{
+ struct zonefs_sb_info *sbi = ZONEFS_SB(root->d_sb);
+
+ if (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_RO)
+ seq_puts(seq, ",errors=remount-ro");
+ if (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_ZRO)
+ seq_puts(seq, ",errors=zone-ro");
+ if (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_ZOL)
+ seq_puts(seq, ",errors=zone-offline");
+ if (sbi->s_mount_opts & ZONEFS_MNTOPT_ERRORS_REPAIR)
+ seq_puts(seq, ",errors=repair");
+
+ return 0;
+}
+
+static int zonefs_remount(struct super_block *sb, int *flags, char *data)
+{
+ sync_filesystem(sb);
+
+ return zonefs_parse_options(sb, data);
+}
+
+static int zonefs_inode_setattr(struct user_namespace *mnt_userns,
+ struct dentry *dentry, struct iattr *iattr)
+{
+ struct inode *inode = d_inode(dentry);
+ int ret;
+
+ if (unlikely(IS_IMMUTABLE(inode)))
+ return -EPERM;
+
+ ret = setattr_prepare(&init_user_ns, dentry, iattr);
+ if (ret)
+ return ret;
+
+ /*
+ * Since files and directories cannot be created nor deleted, do not
+ * allow setting any write attributes on the sub-directories grouping
+ * files by zone type.
+ */
+ if ((iattr->ia_valid & ATTR_MODE) && S_ISDIR(inode->i_mode) &&
+ (iattr->ia_mode & 0222))
+ return -EPERM;
+
+ if (((iattr->ia_valid & ATTR_UID) &&
+ !uid_eq(iattr->ia_uid, inode->i_uid)) ||
+ ((iattr->ia_valid & ATTR_GID) &&
+ !gid_eq(iattr->ia_gid, inode->i_gid))) {
+ ret = dquot_transfer(mnt_userns, inode, iattr);
+ if (ret)
+ return ret;
+ }
+
+ if (iattr->ia_valid & ATTR_SIZE) {
+ ret = zonefs_file_truncate(inode, iattr->ia_size);
+ if (ret)
+ return ret;
+ }
+
+ setattr_copy(&init_user_ns, inode, iattr);
+
+ return 0;
+}
+
+static const struct inode_operations zonefs_dir_inode_operations = {
+ .lookup = simple_lookup,
+ .setattr = zonefs_inode_setattr,
+};
+
+static void zonefs_init_dir_inode(struct inode *parent, struct inode *inode,
+ enum zonefs_ztype ztype)
+{
+ struct super_block *sb = parent->i_sb;
+
+ inode->i_ino = bdev_nr_zones(sb->s_bdev) + ztype + 1;
+ inode_init_owner(&init_user_ns, inode, parent, S_IFDIR | 0555);
+ inode->i_op = &zonefs_dir_inode_operations;
+ inode->i_fop = &simple_dir_operations;
+ set_nlink(inode, 2);
+ inc_nlink(parent);
+}
+
+static const struct inode_operations zonefs_file_inode_operations = {
+ .setattr = zonefs_inode_setattr,
+};
+
+static void zonefs_init_file_inode(struct inode *inode,
+ struct zonefs_zone *z)
+{
+ struct super_block *sb = inode->i_sb;
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+
+ inode->i_private = z;
+
+ inode->i_ino = z->z_sector >> sbi->s_zone_sectors_shift;
+ inode->i_mode = S_IFREG | sbi->s_perm;
+ inode->i_uid = sbi->s_uid;
+ inode->i_gid = sbi->s_gid;
+ inode->i_size = z->z_wpoffset;
+ inode->i_blocks = z->z_capacity >> SECTOR_SHIFT;
+
+ inode->i_op = &zonefs_file_inode_operations;
+ inode->i_fop = &zonefs_file_operations;
+ inode->i_mapping->a_ops = &zonefs_file_aops;
+
+ /* Update the inode access rights depending on the zone condition */
+ z->z_flags |= ZONEFS_ZONE_INIT_MODE;
+ zonefs_inode_update_mode(inode);
+}
+
+static struct dentry *zonefs_create_inode(struct dentry *parent,
+ const char *name,
+ struct zonefs_zone *z,
+ enum zonefs_ztype ztype)
+{
+ struct inode *dir = d_inode(parent);
+ struct dentry *dentry;
+ struct inode *inode;
+ int ret = -ENOMEM;
+
+ dentry = d_alloc_name(parent, name);
+ if (!dentry)
+ return ERR_PTR(ret);
+
+ inode = new_inode(parent->d_sb);
+ if (!inode)
+ goto dput;
+
+ inode->i_ctime = inode->i_mtime = inode->i_atime = dir->i_ctime;
+ if (z)
+ zonefs_init_file_inode(inode, z);
+ else
+ zonefs_init_dir_inode(dir, inode, ztype);
+
+ d_add(dentry, inode);
+ dir->i_size++;
+
+ return dentry;
+
+dput:
+ dput(dentry);
+
+ return ERR_PTR(ret);
+}
+
+struct zonefs_zone_data {
+ struct super_block *sb;
+ unsigned int nr_zones[ZONEFS_ZTYPE_MAX];
+ sector_t cnv_zone_start;
+ struct blk_zone *zones;
+};
+
+/*
+ * Create the inodes for a zone group.
+ */
+static int zonefs_create_zgroup_inodes(struct super_block *sb,
+ enum zonefs_ztype ztype)
+{
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+ struct zonefs_zone_group *zgroup = &sbi->s_zgroup[ztype];
+ struct dentry *dir, *dent;
+ char *file_name;
+ int i, ret = 0;
+
+ if (!zgroup)
+ return -ENOMEM;
+
+ /* If the group is empty, there is nothing to do */
+ if (!zgroup->g_nr_zones)
+ return 0;
+
+ file_name = kmalloc(ZONEFS_NAME_MAX, GFP_KERNEL);
+ if (!file_name)
+ return -ENOMEM;
+
+ dir = zonefs_create_inode(sb->s_root, zonefs_zgroup_name(ztype),
+ NULL, ztype);
+ if (IS_ERR(dir)) {
+ ret = PTR_ERR(dir);
+ goto free;
+ }
+
+ for (i = 0; i < zgroup->g_nr_zones; i++) {
+ /* Use the zone number within its group as the file name */
+ snprintf(file_name, ZONEFS_NAME_MAX - 1, "%u", i);
+ dent = zonefs_create_inode(dir, file_name,
+ &zgroup->g_zones[i], ztype);
+ if (IS_ERR(dent)) {
+ ret = PTR_ERR(dent);
+ break;
+ }
+ }
+
+free:
+ kfree(file_name);
+
+ return ret;
+}
+
+static int zonefs_get_zone_info_cb(struct blk_zone *zone, unsigned int idx,
+ void *data)
+{
+ struct zonefs_zone_data *zd = data;
+ struct super_block *sb = zd->sb;
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+
+ /*
+ * We do not care about the first zone: it contains the super block
+ * and not exposed as a file.
+ */
+ if (!idx)
+ return 0;
+
+ /*
+ * Count the number of zones that will be exposed as files.
+ * For sequential zones, we always have as many files as zones.
+ * FOr conventional zones, the number of files depends on if we have
+ * conventional zones aggregation enabled.
+ */
+ switch (zone->type) {
+ case BLK_ZONE_TYPE_CONVENTIONAL:
+ if (sbi->s_features & ZONEFS_F_AGGRCNV) {
+ /* One file per set of contiguous conventional zones */
+ if (!(sbi->s_zgroup[ZONEFS_ZTYPE_CNV].g_nr_zones) ||
+ zone->start != zd->cnv_zone_start)
+ sbi->s_zgroup[ZONEFS_ZTYPE_CNV].g_nr_zones++;
+ zd->cnv_zone_start = zone->start + zone->len;
+ } else {
+ /* One file per zone */
+ sbi->s_zgroup[ZONEFS_ZTYPE_CNV].g_nr_zones++;
+ }
+ break;
+ case BLK_ZONE_TYPE_SEQWRITE_REQ:
+ case BLK_ZONE_TYPE_SEQWRITE_PREF:
+ sbi->s_zgroup[ZONEFS_ZTYPE_SEQ].g_nr_zones++;
+ break;
+ default:
+ zonefs_err(zd->sb, "Unsupported zone type 0x%x\n",
+ zone->type);
+ return -EIO;
+ }
+
+ memcpy(&zd->zones[idx], zone, sizeof(struct blk_zone));
+
+ return 0;
+}
+
+static int zonefs_get_zone_info(struct zonefs_zone_data *zd)
+{
+ struct block_device *bdev = zd->sb->s_bdev;
+ int ret;
+
+ zd->zones = kvcalloc(bdev_nr_zones(bdev), sizeof(struct blk_zone),
+ GFP_KERNEL);
+ if (!zd->zones)
+ return -ENOMEM;
+
+ /* Get zones information from the device */
+ ret = blkdev_report_zones(bdev, 0, BLK_ALL_ZONES,
+ zonefs_get_zone_info_cb, zd);
+ if (ret < 0) {
+ zonefs_err(zd->sb, "Zone report failed %d\n", ret);
+ return ret;
+ }
+
+ if (ret != bdev_nr_zones(bdev)) {
+ zonefs_err(zd->sb, "Invalid zone report (%d/%u zones)\n",
+ ret, bdev_nr_zones(bdev));
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static inline void zonefs_free_zone_info(struct zonefs_zone_data *zd)
+{
+ kvfree(zd->zones);
+}
+
+/*
+ * Create a zone group and populate it with zone files.
+ */
+static int zonefs_init_zgroup(struct super_block *sb,
+ struct zonefs_zone_data *zd,
+ enum zonefs_ztype ztype)
+{
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+ struct zonefs_zone_group *zgroup = &sbi->s_zgroup[ztype];
+ struct blk_zone *zone, *next, *end;
+ struct zonefs_zone *z;
+ unsigned int n = 0;
+ int ret;
+
+ /* Allocate the zone group. If it is empty, we have nothing to do. */
+ if (!zgroup->g_nr_zones)
+ return 0;
+
+ zgroup->g_zones = kvcalloc(zgroup->g_nr_zones,
+ sizeof(struct zonefs_zone), GFP_KERNEL);
+ if (!zgroup->g_zones)
+ return -ENOMEM;
+
+ /*
+ * Initialize the zone groups using the device zone information.
+ * We always skip the first zone as it contains the super block
+ * and is not use to back a file.
+ */
+ end = zd->zones + bdev_nr_zones(sb->s_bdev);
+ for (zone = &zd->zones[1]; zone < end; zone = next) {
+
+ next = zone + 1;
+ if (zonefs_zone_type(zone) != ztype)
+ continue;
+
+ if (WARN_ON_ONCE(n >= zgroup->g_nr_zones))
+ return -EINVAL;
+
+ /*
+ * For conventional zones, contiguous zones can be aggregated
+ * together to form larger files. Note that this overwrites the
+ * length of the first zone of the set of contiguous zones
+ * aggregated together. If one offline or read-only zone is
+ * found, assume that all zones aggregated have the same
+ * condition.
+ */
+ if (ztype == ZONEFS_ZTYPE_CNV &&
+ (sbi->s_features & ZONEFS_F_AGGRCNV)) {
+ for (; next < end; next++) {
+ if (zonefs_zone_type(next) != ztype)
+ break;
+ zone->len += next->len;
+ zone->capacity += next->capacity;
+ if (next->cond == BLK_ZONE_COND_READONLY &&
+ zone->cond != BLK_ZONE_COND_OFFLINE)
+ zone->cond = BLK_ZONE_COND_READONLY;
+ else if (next->cond == BLK_ZONE_COND_OFFLINE)
+ zone->cond = BLK_ZONE_COND_OFFLINE;
+ }
+ }
+
+ z = &zgroup->g_zones[n];
+ if (ztype == ZONEFS_ZTYPE_CNV)
+ z->z_flags |= ZONEFS_ZONE_CNV;
+ z->z_sector = zone->start;
+ z->z_size = zone->len << SECTOR_SHIFT;
+ if (z->z_size > bdev_zone_sectors(sb->s_bdev) << SECTOR_SHIFT &&
+ !(sbi->s_features & ZONEFS_F_AGGRCNV)) {
+ zonefs_err(sb,
+ "Invalid zone size %llu (device zone sectors %llu)\n",
+ z->z_size,
+ bdev_zone_sectors(sb->s_bdev) << SECTOR_SHIFT);
+ return -EINVAL;
+ }
+
+ z->z_capacity = min_t(loff_t, MAX_LFS_FILESIZE,
+ zone->capacity << SECTOR_SHIFT);
+ z->z_wpoffset = zonefs_check_zone_condition(sb, z, zone);
+
+ sb->s_maxbytes = max(z->z_capacity, sb->s_maxbytes);
+ sbi->s_blocks += z->z_capacity >> sb->s_blocksize_bits;
+ sbi->s_used_blocks += z->z_wpoffset >> sb->s_blocksize_bits;
+
+ /*
+ * For sequential zones, make sure that any open zone is closed
+ * first to ensure that the initial number of open zones is 0,
+ * in sync with the open zone accounting done when the mount
+ * option ZONEFS_MNTOPT_EXPLICIT_OPEN is used.
+ */
+ if (ztype == ZONEFS_ZTYPE_SEQ &&
+ (zone->cond == BLK_ZONE_COND_IMP_OPEN ||
+ zone->cond == BLK_ZONE_COND_EXP_OPEN)) {
+ ret = zonefs_zone_mgmt(sb, z, REQ_OP_ZONE_CLOSE);
+ if (ret)
+ return ret;
+ }
+
+ zonefs_account_active(sb, z);
+
+ n++;
+ }
+
+ if (WARN_ON_ONCE(n != zgroup->g_nr_zones))
+ return -EINVAL;
+
+ zonefs_info(sb, "Zone group \"%s\" has %u file%s\n",
+ zonefs_zgroup_name(ztype),
+ zgroup->g_nr_zones,
+ zgroup->g_nr_zones > 1 ? "s" : "");
+
+ return 0;
+}
+
+static void zonefs_free_zgroups(struct super_block *sb)
+{
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+ enum zonefs_ztype ztype;
+
+ if (!sbi)
+ return;
+
+ for (ztype = 0; ztype < ZONEFS_ZTYPE_MAX; ztype++) {
+ kvfree(sbi->s_zgroup[ztype].g_zones);
+ sbi->s_zgroup[ztype].g_zones = NULL;
+ }
+}
+
+/*
+ * Create a zone group and populate it with zone files.
+ */
+static int zonefs_init_zgroups(struct super_block *sb)
+{
+ struct zonefs_zone_data zd;
+ enum zonefs_ztype ztype;
+ int ret;
+
+ /* First get the device zone information */
+ memset(&zd, 0, sizeof(struct zonefs_zone_data));
+ zd.sb = sb;
+ ret = zonefs_get_zone_info(&zd);
+ if (ret)
+ goto cleanup;
+
+ /* Allocate and initialize the zone groups */
+ for (ztype = 0; ztype < ZONEFS_ZTYPE_MAX; ztype++) {
+ ret = zonefs_init_zgroup(sb, &zd, ztype);
+ if (ret) {
+ zonefs_info(sb,
+ "Zone group \"%s\" initialization failed\n",
+ zonefs_zgroup_name(ztype));
+ break;
+ }
+ }
+
+cleanup:
+ zonefs_free_zone_info(&zd);
+ if (ret)
+ zonefs_free_zgroups(sb);
+
+ return ret;
+}
+
+/*
+ * Read super block information from the device.
+ */
+static int zonefs_read_super(struct super_block *sb)
+{
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+ struct zonefs_super *super;
+ u32 crc, stored_crc;
+ struct page *page;
+ struct bio_vec bio_vec;
+ struct bio bio;
+ int ret;
+
+ page = alloc_page(GFP_KERNEL);
+ if (!page)
+ return -ENOMEM;
+
+ bio_init(&bio, sb->s_bdev, &bio_vec, 1, REQ_OP_READ);
+ bio.bi_iter.bi_sector = 0;
+ bio_add_page(&bio, page, PAGE_SIZE, 0);
+
+ ret = submit_bio_wait(&bio);
+ if (ret)
+ goto free_page;
+
+ super = page_address(page);
+
+ ret = -EINVAL;
+ if (le32_to_cpu(super->s_magic) != ZONEFS_MAGIC)
+ goto free_page;
+
+ stored_crc = le32_to_cpu(super->s_crc);
+ super->s_crc = 0;
+ crc = crc32(~0U, (unsigned char *)super, sizeof(struct zonefs_super));
+ if (crc != stored_crc) {
+ zonefs_err(sb, "Invalid checksum (Expected 0x%08x, got 0x%08x)",
+ crc, stored_crc);
+ goto free_page;
+ }
+
+ sbi->s_features = le64_to_cpu(super->s_features);
+ if (sbi->s_features & ~ZONEFS_F_DEFINED_FEATURES) {
+ zonefs_err(sb, "Unknown features set 0x%llx\n",
+ sbi->s_features);
+ goto free_page;
+ }
+
+ if (sbi->s_features & ZONEFS_F_UID) {
+ sbi->s_uid = make_kuid(current_user_ns(),
+ le32_to_cpu(super->s_uid));
+ if (!uid_valid(sbi->s_uid)) {
+ zonefs_err(sb, "Invalid UID feature\n");
+ goto free_page;
+ }
+ }
+
+ if (sbi->s_features & ZONEFS_F_GID) {
+ sbi->s_gid = make_kgid(current_user_ns(),
+ le32_to_cpu(super->s_gid));
+ if (!gid_valid(sbi->s_gid)) {
+ zonefs_err(sb, "Invalid GID feature\n");
+ goto free_page;
+ }
+ }
+
+ if (sbi->s_features & ZONEFS_F_PERM)
+ sbi->s_perm = le32_to_cpu(super->s_perm);
+
+ if (memchr_inv(super->s_reserved, 0, sizeof(super->s_reserved))) {
+ zonefs_err(sb, "Reserved area is being used\n");
+ goto free_page;
+ }
+
+ import_uuid(&sbi->s_uuid, super->s_uuid);
+ ret = 0;
+
+free_page:
+ __free_page(page);
+
+ return ret;
+}
+
+static const struct super_operations zonefs_sops = {
+ .alloc_inode = zonefs_alloc_inode,
+ .free_inode = zonefs_free_inode,
+ .statfs = zonefs_statfs,
+ .remount_fs = zonefs_remount,
+ .show_options = zonefs_show_options,
+};
+
+/*
+ * Check that the device is zoned. If it is, get the list of zones and create
+ * sub-directories and files according to the device zone configuration and
+ * format options.
+ */
+static int zonefs_fill_super(struct super_block *sb, void *data, int silent)
+{
+ struct zonefs_sb_info *sbi;
+ struct inode *inode;
+ enum zonefs_ztype t;
+ int ret;
+
+ if (!bdev_is_zoned(sb->s_bdev)) {
+ zonefs_err(sb, "Not a zoned block device\n");
+ return -EINVAL;
+ }
+
+ /*
+ * Initialize super block information: the maximum file size is updated
+ * when the zone files are created so that the format option
+ * ZONEFS_F_AGGRCNV which increases the maximum file size of a file
+ * beyond the zone size is taken into account.
+ */
+ sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
+ if (!sbi)
+ return -ENOMEM;
+
+ spin_lock_init(&sbi->s_lock);
+ sb->s_fs_info = sbi;
+ sb->s_magic = ZONEFS_MAGIC;
+ sb->s_maxbytes = 0;
+ sb->s_op = &zonefs_sops;
+ sb->s_time_gran = 1;
+
+ /*
+ * The block size is set to the device zone write granularity to ensure
+ * that write operations are always aligned according to the device
+ * interface constraints.
+ */
+ sb_set_blocksize(sb, bdev_zone_write_granularity(sb->s_bdev));
+ sbi->s_zone_sectors_shift = ilog2(bdev_zone_sectors(sb->s_bdev));
+ sbi->s_uid = GLOBAL_ROOT_UID;
+ sbi->s_gid = GLOBAL_ROOT_GID;
+ sbi->s_perm = 0640;
+ sbi->s_mount_opts = ZONEFS_MNTOPT_ERRORS_RO;
+
+ atomic_set(&sbi->s_wro_seq_files, 0);
+ sbi->s_max_wro_seq_files = bdev_max_open_zones(sb->s_bdev);
+ atomic_set(&sbi->s_active_seq_files, 0);
+ sbi->s_max_active_seq_files = bdev_max_active_zones(sb->s_bdev);
+
+ ret = zonefs_read_super(sb);
+ if (ret)
+ return ret;
+
+ ret = zonefs_parse_options(sb, data);
+ if (ret)
+ return ret;
+
+ zonefs_info(sb, "Mounting %u zones", bdev_nr_zones(sb->s_bdev));
+
+ if (!sbi->s_max_wro_seq_files &&
+ !sbi->s_max_active_seq_files &&
+ sbi->s_mount_opts & ZONEFS_MNTOPT_EXPLICIT_OPEN) {
+ zonefs_info(sb,
+ "No open and active zone limits. Ignoring explicit_open mount option\n");
+ sbi->s_mount_opts &= ~ZONEFS_MNTOPT_EXPLICIT_OPEN;
+ }
+
+ /* Initialize the zone groups */
+ ret = zonefs_init_zgroups(sb);
+ if (ret)
+ goto cleanup;
+
+ /* Create root directory inode */
+ ret = -ENOMEM;
+ inode = new_inode(sb);
+ if (!inode)
+ goto cleanup;
+
+ inode->i_ino = bdev_nr_zones(sb->s_bdev);
+ inode->i_mode = S_IFDIR | 0555;
+ inode->i_ctime = inode->i_mtime = inode->i_atime = current_time(inode);
+ inode->i_op = &zonefs_dir_inode_operations;
+ inode->i_fop = &simple_dir_operations;
+ set_nlink(inode, 2);
+
+ sb->s_root = d_make_root(inode);
+ if (!sb->s_root)
+ goto cleanup;
+
+ /* Create and populate files in zone groups directories */
+ for (t = 0; t < ZONEFS_ZTYPE_MAX; t++) {
+ ret = zonefs_create_zgroup_inodes(sb, t);
+ if (ret)
+ goto cleanup;
+ }
+
+ ret = zonefs_sysfs_register(sb);
+ if (ret)
+ goto cleanup;
+
+ return 0;
+
+cleanup:
+ zonefs_free_zgroups(sb);
+
+ return ret;
+}
+
+static struct dentry *zonefs_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ return mount_bdev(fs_type, flags, dev_name, data, zonefs_fill_super);
+}
+
+static void zonefs_kill_super(struct super_block *sb)
+{
+ struct zonefs_sb_info *sbi = ZONEFS_SB(sb);
+
+ if (sb->s_root)
+ d_genocide(sb->s_root);
+
+ zonefs_sysfs_unregister(sb);
+ zonefs_free_zgroups(sb);
+ kill_block_super(sb);
+ kfree(sbi);
+}
+
+/*
+ * File system definition and registration.
+ */
+static struct file_system_type zonefs_type = {
+ .owner = THIS_MODULE,
+ .name = "zonefs",
+ .mount = zonefs_mount,
+ .kill_sb = zonefs_kill_super,
+ .fs_flags = FS_REQUIRES_DEV,
+};
+
+static int __init zonefs_init_inodecache(void)
+{
+ zonefs_inode_cachep = kmem_cache_create("zonefs_inode_cache",
+ sizeof(struct zonefs_inode_info), 0,
+ (SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT),
+ NULL);
+ if (zonefs_inode_cachep == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
+static void zonefs_destroy_inodecache(void)
+{
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy the inode cache.
+ */
+ rcu_barrier();
+ kmem_cache_destroy(zonefs_inode_cachep);
+}
+
+static int __init zonefs_init(void)
+{
+ int ret;
+
+ BUILD_BUG_ON(sizeof(struct zonefs_super) != ZONEFS_SUPER_SIZE);
+
+ ret = zonefs_init_inodecache();
+ if (ret)
+ return ret;
+
+ ret = zonefs_sysfs_init();
+ if (ret)
+ goto destroy_inodecache;
+
+ ret = register_filesystem(&zonefs_type);
+ if (ret)
+ goto sysfs_exit;
+
+ return 0;
+
+sysfs_exit:
+ zonefs_sysfs_exit();
+destroy_inodecache:
+ zonefs_destroy_inodecache();
+
+ return ret;
+}
+
+static void __exit zonefs_exit(void)
+{
+ unregister_filesystem(&zonefs_type);
+ zonefs_sysfs_exit();
+ zonefs_destroy_inodecache();
+}
+
+MODULE_AUTHOR("Damien Le Moal");
+MODULE_DESCRIPTION("Zone file system for zoned block devices");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_FS("zonefs");
+module_init(zonefs_init);
+module_exit(zonefs_exit);
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-09 00:56:08 +0000