Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 1003 insertions, 0 deletions

diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c
new file mode 100644
index 000000000..cbe59d231
--- /dev/null
+++ b/fs/ocfs2/ioctl.c
@@ -0,0 +1,1003 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/ocfs2/ioctl.c
+ *
+ * Copyright (C) 2006 Herbert Poetzl
+ * adapted from Remy Card's ext2/ioctl.c
+ */
+
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/blkdev.h>
+#include <linux/compat.h>
+#include <linux/fileattr.h>
+
+#include <cluster/masklog.h>
+
+#include "ocfs2.h"
+#include "alloc.h"
+#include "dlmglue.h"
+#include "file.h"
+#include "inode.h"
+#include "journal.h"
+
+#include "ocfs2_fs.h"
+#include "ioctl.h"
+#include "resize.h"
+#include "refcounttree.h"
+#include "sysfile.h"
+#include "dir.h"
+#include "buffer_head_io.h"
+#include "suballoc.h"
+#include "move_extents.h"
+
+#define o2info_from_user(a, b)	\
+		copy_from_user(&(a), (b), sizeof(a))
+#define o2info_to_user(a, b)	\
+		copy_to_user((typeof(a) __user *)b, &(a), sizeof(a))
+
+/*
+ * This is just a best-effort to tell userspace that this request
+ * caused the error.
+ */
+static inline void o2info_set_request_error(struct ocfs2_info_request *kreq,
+					struct ocfs2_info_request __user *req)
+{
+	kreq->ir_flags |= OCFS2_INFO_FL_ERROR;
+	(void)put_user(kreq->ir_flags, (__u32 __user *)&(req->ir_flags));
+}
+
+static inline void o2info_set_request_filled(struct ocfs2_info_request *req)
+{
+	req->ir_flags |= OCFS2_INFO_FL_FILLED;
+}
+
+static inline void o2info_clear_request_filled(struct ocfs2_info_request *req)
+{
+	req->ir_flags &= ~OCFS2_INFO_FL_FILLED;
+}
+
+static inline int o2info_coherent(struct ocfs2_info_request *req)
+{
+	return (!(req->ir_flags & OCFS2_INFO_FL_NON_COHERENT));
+}
+
+int ocfs2_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
+{
+	struct inode *inode = d_inode(dentry);
+	unsigned int flags;
+	int status;
+
+	status = ocfs2_inode_lock(inode, NULL, 0);
+	if (status < 0) {
+		mlog_errno(status);
+		return status;
+	}
+	ocfs2_get_inode_flags(OCFS2_I(inode));
+	flags = OCFS2_I(inode)->ip_attr;
+	ocfs2_inode_unlock(inode, 0);
+
+	fileattr_fill_flags(fa, flags & OCFS2_FL_VISIBLE);
+
+	return status;
+}
+
+int ocfs2_fileattr_set(struct mnt_idmap *idmap,
+		       struct dentry *dentry, struct file_kattr *fa)
+{
+	struct inode *inode = d_inode(dentry);
+	unsigned int flags = fa->flags;
+	struct ocfs2_inode_info *ocfs2_inode = OCFS2_I(inode);
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+	handle_t *handle = NULL;
+	struct buffer_head *bh = NULL;
+	unsigned oldflags;
+	int status;
+
+	if (fileattr_has_fsx(fa))
+		return -EOPNOTSUPP;
+
+	status = ocfs2_inode_lock(inode, &bh, 1);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
+	if (!S_ISDIR(inode->i_mode))
+		flags &= ~OCFS2_DIRSYNC_FL;
+
+	oldflags = ocfs2_inode->ip_attr;
+	flags = flags & OCFS2_FL_MODIFIABLE;
+	flags |= oldflags & ~OCFS2_FL_MODIFIABLE;
+
+	/* Check already done by VFS, but repeat with ocfs lock */
+	status = -EPERM;
+	if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL) &&
+	    !capable(CAP_LINUX_IMMUTABLE))
+		goto bail_unlock;
+
+	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
+	if (IS_ERR(handle)) {
+		status = PTR_ERR(handle);
+		mlog_errno(status);
+		goto bail_unlock;
+	}
+
+	ocfs2_inode->ip_attr = flags;
+	ocfs2_set_inode_flags(inode);
+	inode_set_ctime_current(inode);
+
+	status = ocfs2_mark_inode_dirty(handle, inode, bh);
+	if (status < 0)
+		mlog_errno(status);
+
+	ocfs2_commit_trans(osb, handle);
+
+bail_unlock:
+	ocfs2_inode_unlock(inode, 1);
+bail:
+	brelse(bh);
+
+	return status;
+}
+
+static int ocfs2_info_handle_blocksize(struct inode *inode,
+				       struct ocfs2_info_request __user *req)
+{
+	struct ocfs2_info_blocksize oib;
+
+	if (o2info_from_user(oib, req))
+		return -EFAULT;
+
+	oib.ib_blocksize = inode->i_sb->s_blocksize;
+
+	o2info_set_request_filled(&oib.ib_req);
+
+	if (o2info_to_user(oib, req))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int ocfs2_info_handle_clustersize(struct inode *inode,
+					 struct ocfs2_info_request __user *req)
+{
+	struct ocfs2_info_clustersize oic;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+	if (o2info_from_user(oic, req))
+		return -EFAULT;
+
+	oic.ic_clustersize = osb->s_clustersize;
+
+	o2info_set_request_filled(&oic.ic_req);
+
+	if (o2info_to_user(oic, req))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int ocfs2_info_handle_maxslots(struct inode *inode,
+				      struct ocfs2_info_request __user *req)
+{
+	struct ocfs2_info_maxslots oim;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+	if (o2info_from_user(oim, req))
+		return -EFAULT;
+
+	oim.im_max_slots = osb->max_slots;
+
+	o2info_set_request_filled(&oim.im_req);
+
+	if (o2info_to_user(oim, req))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int ocfs2_info_handle_label(struct inode *inode,
+				   struct ocfs2_info_request __user *req)
+{
+	struct ocfs2_info_label oil;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+	if (o2info_from_user(oil, req))
+		return -EFAULT;
+
+	memcpy(oil.il_label, osb->vol_label, OCFS2_MAX_VOL_LABEL_LEN);
+
+	o2info_set_request_filled(&oil.il_req);
+
+	if (o2info_to_user(oil, req))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int ocfs2_info_handle_uuid(struct inode *inode,
+				  struct ocfs2_info_request __user *req)
+{
+	struct ocfs2_info_uuid oiu;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+	if (o2info_from_user(oiu, req))
+		return -EFAULT;
+
+	memcpy(oiu.iu_uuid_str, osb->uuid_str, OCFS2_TEXT_UUID_LEN + 1);
+
+	o2info_set_request_filled(&oiu.iu_req);
+
+	if (o2info_to_user(oiu, req))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int ocfs2_info_handle_fs_features(struct inode *inode,
+					 struct ocfs2_info_request __user *req)
+{
+	struct ocfs2_info_fs_features oif;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+	if (o2info_from_user(oif, req))
+		return -EFAULT;
+
+	oif.if_compat_features = osb->s_feature_compat;
+	oif.if_incompat_features = osb->s_feature_incompat;
+	oif.if_ro_compat_features = osb->s_feature_ro_compat;
+
+	o2info_set_request_filled(&oif.if_req);
+
+	if (o2info_to_user(oif, req))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int ocfs2_info_handle_journal_size(struct inode *inode,
+					  struct ocfs2_info_request __user *req)
+{
+	struct ocfs2_info_journal_size oij;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+	if (o2info_from_user(oij, req))
+		return -EFAULT;
+
+	oij.ij_journal_size = i_size_read(osb->journal->j_inode);
+
+	o2info_set_request_filled(&oij.ij_req);
+
+	if (o2info_to_user(oij, req))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int ocfs2_info_scan_inode_alloc(struct ocfs2_super *osb,
+				       struct inode *inode_alloc, u64 blkno,
+				       struct ocfs2_info_freeinode *fi,
+				       u32 slot)
+{
+	int status = 0, unlock = 0;
+
+	struct buffer_head *bh = NULL;
+	struct ocfs2_dinode *dinode_alloc = NULL;
+
+	if (inode_alloc)
+		inode_lock(inode_alloc);
+
+	if (inode_alloc && o2info_coherent(&fi->ifi_req)) {
+		status = ocfs2_inode_lock(inode_alloc, &bh, 0);
+		if (status < 0) {
+			mlog_errno(status);
+			goto bail;
+		}
+		unlock = 1;
+	} else {
+		status = ocfs2_read_blocks_sync(osb, blkno, 1, &bh);
+		if (status < 0) {
+			mlog_errno(status);
+			goto bail;
+		}
+	}
+
+	dinode_alloc = (struct ocfs2_dinode *)bh->b_data;
+
+	fi->ifi_stat[slot].lfi_total =
+		le32_to_cpu(dinode_alloc->id1.bitmap1.i_total);
+	fi->ifi_stat[slot].lfi_free =
+		le32_to_cpu(dinode_alloc->id1.bitmap1.i_total) -
+		le32_to_cpu(dinode_alloc->id1.bitmap1.i_used);
+
+bail:
+	if (unlock)
+		ocfs2_inode_unlock(inode_alloc, 0);
+
+	if (inode_alloc)
+		inode_unlock(inode_alloc);
+
+	brelse(bh);
+
+	return status;
+}
+
+static int ocfs2_info_handle_freeinode(struct inode *inode,
+				       struct ocfs2_info_request __user *req)
+{
+	u32 i;
+	u64 blkno = -1;
+	char namebuf[40];
+	int status, type = INODE_ALLOC_SYSTEM_INODE;
+	struct ocfs2_info_freeinode *oifi = NULL;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+	struct inode *inode_alloc = NULL;
+
+	oifi = kzalloc_obj(struct ocfs2_info_freeinode);
+	if (!oifi) {
+		status = -ENOMEM;
+		mlog_errno(status);
+		goto out_err;
+	}
+
+	if (o2info_from_user(*oifi, req)) {
+		status = -EFAULT;
+		goto out_free;
+	}
+
+	oifi->ifi_slotnum = osb->max_slots;
+
+	for (i = 0; i < oifi->ifi_slotnum; i++) {
+		if (o2info_coherent(&oifi->ifi_req)) {
+			inode_alloc = ocfs2_get_system_file_inode(osb, type, i);
+			if (!inode_alloc) {
+				mlog(ML_ERROR, "unable to get alloc inode in "
+				    "slot %u\n", i);
+				status = -EIO;
+				goto bail;
+			}
+		} else {
+			int len = ocfs2_sprintf_system_inode_name(namebuf,
+								  sizeof(namebuf),
+								  type, i);
+			status = ocfs2_lookup_ino_from_name(osb->sys_root_inode,
+							    namebuf, len, &blkno);
+			if (status < 0) {
+				status = -ENOENT;
+				goto bail;
+			}
+		}
+
+		status = ocfs2_info_scan_inode_alloc(osb, inode_alloc, blkno, oifi, i);
+
+		iput(inode_alloc);
+		inode_alloc = NULL;
+
+		if (status < 0)
+			goto bail;
+	}
+
+	o2info_set_request_filled(&oifi->ifi_req);
+
+	if (o2info_to_user(*oifi, req)) {
+		status = -EFAULT;
+		goto out_free;
+	}
+
+	status = 0;
+bail:
+	if (status)
+		o2info_set_request_error(&oifi->ifi_req, req);
+out_free:
+	kfree(oifi);
+out_err:
+	return status;
+}
+
+static void o2ffg_update_histogram(struct ocfs2_info_free_chunk_list *hist,
+				   unsigned int chunksize)
+{
+	u32 index;
+
+	index = __ilog2_u32(chunksize);
+	if (index >= OCFS2_INFO_MAX_HIST)
+		index = OCFS2_INFO_MAX_HIST - 1;
+
+	hist->fc_chunks[index]++;
+	hist->fc_clusters[index] += chunksize;
+}
+
+static void o2ffg_update_stats(struct ocfs2_info_freefrag_stats *stats,
+			       unsigned int chunksize)
+{
+	if (chunksize > stats->ffs_max)
+		stats->ffs_max = chunksize;
+
+	if (chunksize < stats->ffs_min)
+		stats->ffs_min = chunksize;
+
+	stats->ffs_avg += chunksize;
+	stats->ffs_free_chunks_real++;
+}
+
+static void ocfs2_info_update_ffg(struct ocfs2_info_freefrag *ffg,
+				  unsigned int chunksize)
+{
+	o2ffg_update_histogram(&(ffg->iff_ffs.ffs_fc_hist), chunksize);
+	o2ffg_update_stats(&(ffg->iff_ffs), chunksize);
+}
+
+static int ocfs2_info_freefrag_scan_chain(struct ocfs2_super *osb,
+					  struct inode *gb_inode,
+					  struct ocfs2_dinode *gb_dinode,
+					  struct ocfs2_chain_rec *rec,
+					  struct ocfs2_info_freefrag *ffg,
+					  u32 chunks_in_group)
+{
+	int status = 0, used;
+	u64 blkno;
+
+	struct buffer_head *bh = NULL;
+	struct ocfs2_group_desc *bg = NULL;
+
+	unsigned int max_bits, max_bitmap_bits, num_clusters;
+	unsigned int offset = 0, cluster, chunk;
+	unsigned int chunk_free, last_chunksize = 0;
+
+	if (!le32_to_cpu(rec->c_free))
+		goto bail;
+
+	max_bitmap_bits = 8 * ocfs2_group_bitmap_size(osb->sb, 0,
+					      osb->s_feature_incompat);
+
+	do {
+		if (!bg)
+			blkno = le64_to_cpu(rec->c_blkno);
+		else
+			blkno = le64_to_cpu(bg->bg_next_group);
+
+		if (bh) {
+			brelse(bh);
+			bh = NULL;
+		}
+
+		if (o2info_coherent(&ffg->iff_req))
+			status = ocfs2_read_group_descriptor(gb_inode,
+							     gb_dinode,
+							     blkno, &bh);
+		else
+			status = ocfs2_read_blocks_sync(osb, blkno, 1, &bh);
+
+		if (status < 0) {
+			mlog(ML_ERROR, "Can't read the group descriptor # "
+			     "%llu from device.", (unsigned long long)blkno);
+			status = -EIO;
+			goto bail;
+		}
+
+		bg = (struct ocfs2_group_desc *)bh->b_data;
+
+		if (!le16_to_cpu(bg->bg_free_bits_count))
+			continue;
+
+		max_bits = le16_to_cpu(bg->bg_bits);
+
+		/*
+		 * Non-coherent scans read raw blocks and do not get the
+		 * bg_bits validation from
+		 * ocfs2_read_group_descriptor().
+		 */
+		if (max_bits > max_bitmap_bits) {
+			mlog(ML_ERROR,
+			     "Group desc #%llu has %u bits, max bitmap bits %u\n",
+			     (unsigned long long)blkno, max_bits, max_bitmap_bits);
+			max_bits = max_bitmap_bits;
+		}
+
+		offset = 0;
+
+		for (chunk = 0; chunk < chunks_in_group; chunk++) {
+			/*
+			 * last chunk may be not an entire one.
+			 */
+			if ((offset + ffg->iff_chunksize) > max_bits)
+				num_clusters = max_bits - offset;
+			else
+				num_clusters = ffg->iff_chunksize;
+
+			chunk_free = 0;
+			for (cluster = 0; cluster < num_clusters; cluster++) {
+				used = ocfs2_test_bit(offset,
+						(unsigned long *)bg->bg_bitmap);
+				/*
+				 * - chunk_free counts free clusters in #N chunk.
+				 * - last_chunksize records the size(in) clusters
+				 *   for the last real free chunk being counted.
+				 */
+				if (!used) {
+					last_chunksize++;
+					chunk_free++;
+				}
+
+				if (used && last_chunksize) {
+					ocfs2_info_update_ffg(ffg,
+							      last_chunksize);
+					last_chunksize = 0;
+				}
+
+				offset++;
+			}
+
+			if (chunk_free == ffg->iff_chunksize)
+				ffg->iff_ffs.ffs_free_chunks++;
+		}
+
+		/*
+		 * need to update the info for last free chunk.
+		 */
+		if (last_chunksize)
+			ocfs2_info_update_ffg(ffg, last_chunksize);
+
+	} while (le64_to_cpu(bg->bg_next_group));
+
+bail:
+	brelse(bh);
+
+	return status;
+}
+
+static int ocfs2_info_freefrag_scan_bitmap(struct ocfs2_super *osb,
+					   struct inode *gb_inode, u64 blkno,
+					   struct ocfs2_info_freefrag *ffg)
+{
+	u32 chunks_in_group;
+	int status = 0, unlock = 0, i;
+
+	struct buffer_head *bh = NULL;
+	struct ocfs2_chain_list *cl = NULL;
+	struct ocfs2_chain_rec *rec = NULL;
+	struct ocfs2_dinode *gb_dinode = NULL;
+
+	if (gb_inode)
+		inode_lock(gb_inode);
+
+	if (o2info_coherent(&ffg->iff_req)) {
+		status = ocfs2_inode_lock(gb_inode, &bh, 0);
+		if (status < 0) {
+			mlog_errno(status);
+			goto bail;
+		}
+		unlock = 1;
+	} else {
+		status = ocfs2_read_blocks_sync(osb, blkno, 1, &bh);
+		if (status < 0) {
+			mlog_errno(status);
+			goto bail;
+		}
+	}
+
+	gb_dinode = (struct ocfs2_dinode *)bh->b_data;
+	cl = &(gb_dinode->id2.i_chain);
+
+	/*
+	 * Chunksize(in) clusters from userspace should be
+	 * less than clusters in a group.
+	 */
+	if (ffg->iff_chunksize > le16_to_cpu(cl->cl_cpg)) {
+		status = -EINVAL;
+		goto bail;
+	}
+
+	memset(&ffg->iff_ffs, 0, sizeof(struct ocfs2_info_freefrag_stats));
+
+	ffg->iff_ffs.ffs_min = ~0U;
+	ffg->iff_ffs.ffs_clusters =
+			le32_to_cpu(gb_dinode->id1.bitmap1.i_total);
+	ffg->iff_ffs.ffs_free_clusters = ffg->iff_ffs.ffs_clusters -
+			le32_to_cpu(gb_dinode->id1.bitmap1.i_used);
+
+	chunks_in_group = le16_to_cpu(cl->cl_cpg) / ffg->iff_chunksize + 1;
+
+	for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
+		rec = &(cl->cl_recs[i]);
+		status = ocfs2_info_freefrag_scan_chain(osb, gb_inode,
+							gb_dinode,
+							rec, ffg,
+							chunks_in_group);
+		if (status)
+			goto bail;
+	}
+
+	if (ffg->iff_ffs.ffs_free_chunks_real)
+		ffg->iff_ffs.ffs_avg = (ffg->iff_ffs.ffs_avg /
+					ffg->iff_ffs.ffs_free_chunks_real);
+bail:
+	if (unlock)
+		ocfs2_inode_unlock(gb_inode, 0);
+
+	if (gb_inode)
+		inode_unlock(gb_inode);
+
+	iput(gb_inode);
+	brelse(bh);
+
+	return status;
+}
+
+static int ocfs2_info_handle_freefrag(struct inode *inode,
+				      struct ocfs2_info_request __user *req)
+{
+	u64 blkno = -1;
+	char namebuf[40];
+	int status, type = GLOBAL_BITMAP_SYSTEM_INODE;
+
+	struct ocfs2_info_freefrag *oiff;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+	struct inode *gb_inode = NULL;
+
+	oiff = kzalloc_obj(struct ocfs2_info_freefrag);
+	if (!oiff) {
+		status = -ENOMEM;
+		mlog_errno(status);
+		goto out_err;
+	}
+
+	if (o2info_from_user(*oiff, req)) {
+		status = -EFAULT;
+		goto out_free;
+	}
+	/*
+	 * chunksize from userspace should be power of 2.
+	 */
+	if ((oiff->iff_chunksize & (oiff->iff_chunksize - 1)) ||
+	    (!oiff->iff_chunksize)) {
+		status = -EINVAL;
+		goto bail;
+	}
+
+	if (o2info_coherent(&oiff->iff_req)) {
+		gb_inode = ocfs2_get_system_file_inode(osb, type,
+						       OCFS2_INVALID_SLOT);
+		if (!gb_inode) {
+			mlog(ML_ERROR, "unable to get global_bitmap inode\n");
+			status = -EIO;
+			goto bail;
+		}
+	} else {
+		int len = ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf),
+							  type, OCFS2_INVALID_SLOT);
+		status = ocfs2_lookup_ino_from_name(osb->sys_root_inode,
+						    namebuf, len, &blkno);
+		if (status < 0) {
+			status = -ENOENT;
+			goto bail;
+		}
+	}
+
+	status = ocfs2_info_freefrag_scan_bitmap(osb, gb_inode, blkno, oiff);
+	if (status < 0)
+		goto bail;
+
+	o2info_set_request_filled(&oiff->iff_req);
+
+	if (o2info_to_user(*oiff, req)) {
+		status = -EFAULT;
+		goto out_free;
+	}
+
+	status = 0;
+bail:
+	if (status)
+		o2info_set_request_error(&oiff->iff_req, req);
+out_free:
+	kfree(oiff);
+out_err:
+	return status;
+}
+
+static int ocfs2_info_handle_unknown(struct inode *inode,
+				     struct ocfs2_info_request __user *req)
+{
+	struct ocfs2_info_request oir;
+
+	if (o2info_from_user(oir, req))
+		return -EFAULT;
+
+	o2info_clear_request_filled(&oir);
+
+	if (o2info_to_user(oir, req))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * Validate and distinguish OCFS2_IOC_INFO requests.
+ *
+ * - validate the magic number.
+ * - distinguish different requests.
+ * - validate size of different requests.
+ */
+static int ocfs2_info_handle_request(struct inode *inode,
+				     struct ocfs2_info_request __user *req)
+{
+	int status = -EFAULT;
+	struct ocfs2_info_request oir;
+
+	if (o2info_from_user(oir, req))
+		goto bail;
+
+	status = -EINVAL;
+	if (oir.ir_magic != OCFS2_INFO_MAGIC)
+		goto bail;
+
+	switch (oir.ir_code) {
+	case OCFS2_INFO_BLOCKSIZE:
+		if (oir.ir_size == sizeof(struct ocfs2_info_blocksize))
+			status = ocfs2_info_handle_blocksize(inode, req);
+		break;
+	case OCFS2_INFO_CLUSTERSIZE:
+		if (oir.ir_size == sizeof(struct ocfs2_info_clustersize))
+			status = ocfs2_info_handle_clustersize(inode, req);
+		break;
+	case OCFS2_INFO_MAXSLOTS:
+		if (oir.ir_size == sizeof(struct ocfs2_info_maxslots))
+			status = ocfs2_info_handle_maxslots(inode, req);
+		break;
+	case OCFS2_INFO_LABEL:
+		if (oir.ir_size == sizeof(struct ocfs2_info_label))
+			status = ocfs2_info_handle_label(inode, req);
+		break;
+	case OCFS2_INFO_UUID:
+		if (oir.ir_size == sizeof(struct ocfs2_info_uuid))
+			status = ocfs2_info_handle_uuid(inode, req);
+		break;
+	case OCFS2_INFO_FS_FEATURES:
+		if (oir.ir_size == sizeof(struct ocfs2_info_fs_features))
+			status = ocfs2_info_handle_fs_features(inode, req);
+		break;
+	case OCFS2_INFO_JOURNAL_SIZE:
+		if (oir.ir_size == sizeof(struct ocfs2_info_journal_size))
+			status = ocfs2_info_handle_journal_size(inode, req);
+		break;
+	case OCFS2_INFO_FREEINODE:
+		if (oir.ir_size == sizeof(struct ocfs2_info_freeinode))
+			status = ocfs2_info_handle_freeinode(inode, req);
+		break;
+	case OCFS2_INFO_FREEFRAG:
+		if (oir.ir_size == sizeof(struct ocfs2_info_freefrag))
+			status = ocfs2_info_handle_freefrag(inode, req);
+		break;
+	default:
+		status = ocfs2_info_handle_unknown(inode, req);
+		break;
+	}
+
+bail:
+	return status;
+}
+
+static int ocfs2_get_request_ptr(struct ocfs2_info *info, int idx,
+				 u64 *req_addr, int compat_flag)
+{
+	int status = -EFAULT;
+	u64 __user *bp = NULL;
+
+	if (compat_flag) {
+#ifdef CONFIG_COMPAT
+		/*
+		 * pointer bp stores the base address of a pointers array,
+		 * which collects all addresses of separate request.
+		 */
+		bp = (u64 __user *)(unsigned long)compat_ptr(info->oi_requests);
+#else
+		BUG();
+#endif
+	} else
+		bp = (u64 __user *)(unsigned long)(info->oi_requests);
+
+	if (o2info_from_user(*req_addr, bp + idx))
+		goto bail;
+
+	status = 0;
+bail:
+	return status;
+}
+
+/*
+ * OCFS2_IOC_INFO handles an array of requests passed from userspace.
+ *
+ * ocfs2_info_handle() receives a large info aggregation, grab and
+ * validate the request count from header, then break it into small
+ * pieces, later specific handlers can handle them one by one.
+ *
+ * Idea here is to make each separate request small enough to ensure
+ * a better backward&forward compatibility, since a small piece of
+ * request will be less likely to be broken if disk layout get changed.
+ */
+static noinline_for_stack int
+ocfs2_info_handle(struct inode *inode, struct ocfs2_info *info, int compat_flag)
+{
+	int i, status = 0;
+	u64 req_addr;
+	struct ocfs2_info_request __user *reqp;
+
+	if ((info->oi_count > OCFS2_INFO_MAX_REQUEST) ||
+	    (!info->oi_requests)) {
+		status = -EINVAL;
+		goto bail;
+	}
+
+	for (i = 0; i < info->oi_count; i++) {
+
+		status = ocfs2_get_request_ptr(info, i, &req_addr, compat_flag);
+		if (status)
+			break;
+
+		reqp = (struct ocfs2_info_request __user *)(unsigned long)req_addr;
+		if (!reqp) {
+			status = -EINVAL;
+			goto bail;
+		}
+
+		status = ocfs2_info_handle_request(inode, reqp);
+		if (status)
+			break;
+	}
+
+bail:
+	return status;
+}
+
+long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+	struct inode *inode = file_inode(filp);
+	void __user *argp = (void __user *)arg;
+	int status;
+
+	switch (cmd) {
+	case OCFS2_IOC_RESVSP:
+	case OCFS2_IOC_RESVSP64:
+	case OCFS2_IOC_UNRESVSP:
+	case OCFS2_IOC_UNRESVSP64:
+	{
+		struct ocfs2_space_resv sr;
+
+		if (copy_from_user(&sr, (int __user *) arg, sizeof(sr)))
+			return -EFAULT;
+
+		return ocfs2_change_file_space(filp, cmd, &sr);
+	}
+	case OCFS2_IOC_GROUP_EXTEND:
+	{
+		int new_clusters;
+
+		if (!capable(CAP_SYS_RESOURCE))
+			return -EPERM;
+
+		if (get_user(new_clusters, (int __user *)arg))
+			return -EFAULT;
+
+		status = mnt_want_write_file(filp);
+		if (status)
+			return status;
+		status = ocfs2_group_extend(inode, new_clusters);
+		mnt_drop_write_file(filp);
+		return status;
+	}
+	case OCFS2_IOC_GROUP_ADD:
+	case OCFS2_IOC_GROUP_ADD64:
+	{
+		struct ocfs2_new_group_input input;
+
+		if (!capable(CAP_SYS_RESOURCE))
+			return -EPERM;
+
+		if (copy_from_user(&input, (int __user *) arg, sizeof(input)))
+			return -EFAULT;
+
+		status = mnt_want_write_file(filp);
+		if (status)
+			return status;
+		status = ocfs2_group_add(inode, &input);
+		mnt_drop_write_file(filp);
+		return status;
+	}
+	case OCFS2_IOC_REFLINK:
+	{
+		struct reflink_arguments args;
+		const char __user *old_path;
+		const char __user *new_path;
+		bool preserve;
+
+		if (copy_from_user(&args, argp, sizeof(args)))
+			return -EFAULT;
+		old_path = (const char __user *)(unsigned long)args.old_path;
+		new_path = (const char __user *)(unsigned long)args.new_path;
+		preserve = (args.preserve != 0);
+
+		return ocfs2_reflink_ioctl(inode, old_path, new_path, preserve);
+	}
+	case OCFS2_IOC_INFO:
+	{
+		struct ocfs2_info info;
+
+		if (copy_from_user(&info, argp, sizeof(struct ocfs2_info)))
+			return -EFAULT;
+
+		return ocfs2_info_handle(inode, &info, 0);
+	}
+	case FITRIM:
+	{
+		struct super_block *sb = inode->i_sb;
+		struct fstrim_range range;
+		int ret = 0;
+
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+
+		if (!bdev_max_discard_sectors(sb->s_bdev))
+			return -EOPNOTSUPP;
+
+		if (copy_from_user(&range, argp, sizeof(range)))
+			return -EFAULT;
+
+		range.minlen = max_t(u64, bdev_discard_granularity(sb->s_bdev),
+				     range.minlen);
+		ret = ocfs2_trim_fs(sb, &range);
+		if (ret < 0)
+			return ret;
+
+		if (copy_to_user(argp, &range, sizeof(range)))
+			return -EFAULT;
+
+		return 0;
+	}
+	case OCFS2_IOC_MOVE_EXT:
+		return ocfs2_ioctl_move_extents(filp, argp);
+	default:
+		return -ENOTTY;
+	}
+}
+
+#ifdef CONFIG_COMPAT
+long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
+{
+	bool preserve;
+	struct reflink_arguments args;
+	struct inode *inode = file_inode(file);
+	struct ocfs2_info info;
+	void __user *argp = (void __user *)arg;
+
+	switch (cmd) {
+	case OCFS2_IOC_RESVSP:
+	case OCFS2_IOC_RESVSP64:
+	case OCFS2_IOC_UNRESVSP:
+	case OCFS2_IOC_UNRESVSP64:
+	case OCFS2_IOC_GROUP_EXTEND:
+	case OCFS2_IOC_GROUP_ADD:
+	case OCFS2_IOC_GROUP_ADD64:
+		break;
+	case OCFS2_IOC_REFLINK:
+		if (copy_from_user(&args, argp, sizeof(args)))
+			return -EFAULT;
+		preserve = (args.preserve != 0);
+
+		return ocfs2_reflink_ioctl(inode, compat_ptr(args.old_path),
+					   compat_ptr(args.new_path), preserve);
+	case OCFS2_IOC_INFO:
+		if (copy_from_user(&info, argp, sizeof(struct ocfs2_info)))
+			return -EFAULT;
+
+		return ocfs2_info_handle(inode, &info, 1);
+	case FITRIM:
+	case OCFS2_IOC_MOVE_EXT:
+		break;
+	default:
+		return -ENOIOCTLCMD;
+	}
+
+	return ocfs2_ioctl(file, cmd, arg);
+}
+#endif