No one currently needs EXT4_INODE_CASEFOLD, but add it to keep the
EXT4_INODE_* definitions in sync with the EXT4_*_FL definitions.

Also make it clearer that the casefold flag is only for directories.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200510215252.87833-1-ebiggers@kernel.orgSigned-off-by: Theodore Ts'o <tytso@mit.edu>

The path performing block allocations in ext4_ext_map_blocks() contains
code trimming the length of a new extent that is repeated later
in the function.  This code is both redundant and unnecessary as the
exact length of the new extent has already been calculated.  Rewrite the
instantiation of the map struct in this case to use the available
values, avoiding the overhead of unnecessary conversions and improving
clarity.  Add another map struct instantiation tailored specifically to
the separate case for an existing written extent.  Remove an old comment
that no longer appears applicable to the current code.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200510155805.18808-1-enwlinux@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>

ext_debug() msgs could be helpful, provided those could be enabled
without recompiling kernel and also if we could selectively enable
only required prints for case by case debugging.

So make ext_debug() implementation use pr_debug().
Also change ext_debug() to be defined with CONFIG_EXT4_DEBUG.
So EXT_DEBUG macro now mostly remain for below 3 functions.
ext4_ext_show_path/leaf/move() (whose print msgs use ext_debug()
which again could be dynamically enabled using pr_debug())

This also changes the ext_debug() to take inode as a parameter
to add inode no. in all of it's msgs.
Prints additional info like process name / pid, superblock id etc.
This also removes any explicit function names passed in ext_debug().
Since ext_debug() on it's own prints file, func and line no.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/d31dc189b0aeda9384fe7665e36da7cd8c61571f.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

mb_debug() msg had only 1 control level for all type of msgs.
And if we enable mballoc_debug then all of those msgs would be enabled.
Instead of adding multiple debug levels for mb_debug() msgs, use
pr_debug() with which we could have finer control to print msgs at all
of different levels (i.e. at file, func, line no.).

Also add process name/pid, superblk id, and other info in mb_debug()
msg. This also kills the mballoc_debug module parameter, since it is
not needed any more.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/f0c660cbde9e2edbe95c67942ca9ad80dd2231eb.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Replace EXT_DEBUG with __maybe_unused from inside
ext4_ext_handle_unwritten_extents() function.

There should be no functionality change in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/ae335b94506cd9db9d2648c1f4dd25a80f9f3ce2.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

ext4_map_blocks() has ext_debug msg early at the start of function.
We also get ext_debug msg if we could allocate a block from
ext4_ext_map_blocks(). But there is no ext_debug() msg in case of
block allocation failure. So add one along with error code.

Also add more info in ext_debug() msg like how many blocks were allocated
v/s how many were requested in ext4_ext_map_blocks().
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/1610ec2aa932396be00f9d552fe29da473ead176.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Simply use BIT() macro for all BH_** state bits instead of open
coding it.

There should be no functionality change in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/57667689f51a3f9dba2fcef7d3425187fa3ba69f.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Use task_pid_nr() function instead of current->pid.
There should be no functionality change in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/4b58403e15e9c8deb34a1b93deb3fc9cd153ab84.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Make sure to check for e4b->bd_info->bb_bitmap == NULL, in
mb_cmp_bitmaps() and return if NULL, to avoid possible NULL ptr
dereference. Similar to how we do this in other ifdef DOUBLE_CHECK
functions.

Also remove the BUG_ON() logic if kmalloc() or ext4_read_block_bitmap()
fails. We should simply mark grp->bb_bitmap as NULL if above happens.
In fact ext4_read_block_bitmap() may even return an error in case of resize
ioctl. Hence remove this BUG_ON logic (fstests ext4/032 may trigger
this).

Link: https://lore.kernel.org/r/9a54f8a696ff17c057cd571be3d15ac3ec1407f1.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

This patch implemets mb_group_bb_bitmap_alloc() and
mb_group_bb_bitmap_free() function to remove #ifdef DOUBLE_CHECK macro
and it's related code from inside
ext4_mb_add_groupinfo()/ext4_mb_release().

There should be no functionality change in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/8c2095d74b779f0254a19b24982490dc6f07c4f9.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Change return type of function ext4_mb_use_preallocated() to bool to
better reflect what this function can return.

There should be no functionality change in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/7880cb6ef911465beafefcd7e9c3ea214688744b.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

This patch simplifies error handling logic in ext4_init_mballoc(),
by adding all the cleanups at one place at the end of that function.

There should be no functionality change in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/8621a7bc68f7107a9ac4292afeb784515333bd25.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Fix few other format specifiers in mb_debug() msgs.
As such no other functionality change in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/574fa7f833abf2dbf3b53a2fea3195e71f6cdbd8.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

pa->pa_len is an integer. Fix all of the format specifier used in
mb_debug() for pa_len to %d instead of %u.

As such no functionality change in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/af4987f643c586f62bcc9961e43f0a67151d5551.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

This patch adds some more debugging mb_debug() msgs to help improve
mballoc code debugging.
Other than adding more mb_debug() msgs at few more places,
there should be no other functionality change in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/5fc8e7788b924e211fcfa4a4c1d2f8503511661a.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

This factors out ext4_mb_show_pa() function to show all the group's
preallocation info. This could be useful info to be added in later
patches.

There should be no functionality change in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/8f07d890b0038dcc935e9c10e6043ec9f3792721.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Improve the debugging msg by also printing even if bb_free is 0.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/c894f1d1d30f86ae38f4e3a861949665b6dc61cd.1589086800.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

We can't fail in the truncate path without requiring an fsck.
Add work around for this by using a combination of retry loops
and the __GFP_NOFAIL flag.

From: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Anna Pendleton <pendleton@google.com>
Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20200507175028.15061-1-pendleton@google.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

'igrab(d_inode(dentry->d_parent))' without holding dentry->d_lock is
broken because without d_lock, d_parent can be concurrently changed due
to a rename().  Then if the old directory is immediately deleted, old
d_parent->inode can be NULL.  That causes a NULL dereference in igrab().

To fix this, use dget_parent() to safely grab a reference to the parent
dentry, which pins the inode.  This also eliminates the need to use
d_find_any_alias() other than for the initial inode, as we no longer
throw away the dentry at each step.

This is an extremely hard race to hit, but it is possible.  Adding a
udelay() in between the reads of ->d_parent and its ->d_inode makes it
reproducible on a no-journal filesystem using the following program:

    #include <fcntl.h>
    #include <unistd.h>

    int main()
    {
        if (fork()) {
            for (;;) {
                mkdir("dir1", 0700);
                int fd = open("dir1/file", O_RDWR|O_CREAT|O_SYNC);
                write(fd, "X", 1);
                close(fd);
            }
        } else {
            mkdir("dir2", 0700);
            for (;;) {
                rename("dir1/file", "dir2/file");
                rmdir("dir1");
            }
        }
    }

Fixes: d59729f4 ("ext4: fix races in ext4_sync_parent()")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200506183140.541194-1-ebiggers@kernel.orgSigned-off-by: Theodore Ts'o <tytso@mit.edu>

s/extnets/extents/
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20200503200647.154701-1-christophe.jaillet@wanadoo.frSigned-off-by: Theodore Ts'o <tytso@mit.edu>

If ext4_ext_convert_to_initialized() fails when called within
ext4_ext_handle_unwritten_extents(), immediately error out through the
exit point at function end.  Fix the error handling in the event
ext4_ext_convert_to_initialized() returns 0, which it shouldn't do when
converting an existing extent.  The current code returns the passed in
value of allocated (which is likely non-zero) while failing to set
m_flags, m_pblk, and m_len.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200430185320.23001-5-enwlinux@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

If the call to ext4_split_convert_extents() fails in the
EXT4_GET_BLOCKS_PRE_IO case within ext4_ext_handle_unwritten_extents(),
error out through the exit point at function end rather than jumping
through an intermediate point.  Fix the error handling in the event
ext4_split_convert_extents() returns 0, which it shouldn't do when
splitting an existing extent.  The current code returns the passed in
value of allocated (which is likely non-zero) while failing to set
m_flags, m_pblk, and m_len.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200430185320.23001-4-enwlinux@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Remove the redundant code assigning values to ext4_map_blocks components
in ext4_ext_handle_unwritten_extents() for the EXT4_GET_BLOCKS_CONVERT
case, using the code at the function exit instead.  Clean up and reorder
that code to eliminate more redundancy and improve readability.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200430185320.23001-3-enwlinux@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

There's no call to ext4_map_blocks() in the current ext4 code with a
flags argument that combines EXT4_GET_BLOCKS_CONVERT and
EXT4_GET_BLOCKS_ZERO.  Remove the code that corresponds to this case
from ext4_ext_handle_unwritten_extents().
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200430185320.23001-2-enwlinux@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Don't ignore return values from ext4_ext_dirty, since the errors
indicate valid failures below Ext4.  In all of the other instances of
ext4_ext_dirty calls, the error return value is handled in some
way. This patch makes those remaining couple of places to handle
ext4_ext_dirty errors as well. In case of ext4_split_extent_at(), the
ignorance of return value is intentional. The reason is that we are
already in error path and there isn't much we can do if ext4_ext_dirty
returns error. This patch adds a comment for that case explaining why
we ignore the return value.

In the longer run, we probably should
make sure that errors from other mark_dirty routines are handled as
well.

Ran gce-xfstests smoke tests and verified that there were no
regressions.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200427013438.219117-2-harshadshirwadkar@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

ext4_mark_inode_dirty() can fail for real reasons. Ignoring its return
value may lead ext4 to ignore real failures that would result in
corruption / crashes. Harden ext4_mark_inode_dirty error paths to fail
as soon as possible and return errors to the caller whenever
appropriate.

One of the possible scnearios when this bug could affected is that
while creating a new inode, its directory entry gets added
successfully but while writing the inode itself mark_inode_dirty
returns error which is ignored. This would result in inconsistency
that the directory entry points to a non-existent inode.

Ran gce-xfstests smoke tests and verified that there were no
regressions.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20200427013438.219117-1-harshadshirwadkar@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Don't pass error pointers to brelse().

commit 7159a986 ("ext4: fix some error pointer dereferences") has fixed
some cases, fix the remaining one case.

Once ext4_xattr_block_find()->ext4_sb_bread() failed, error pointer is
stored in @bs->bh, which will be passed to brelse() in the cleanup
routine of ext4_xattr_set_handle(). This will then cause a NULL panic
crash in __brelse().

BUG: unable to handle kernel NULL pointer dereference at 000000000000005b
RIP: 0010:__brelse+0x1b/0x50
Call Trace:
 ext4_xattr_set_handle+0x163/0x5d0
 ext4_xattr_set+0x95/0x110
 __vfs_setxattr+0x6b/0x80
 __vfs_setxattr_noperm+0x68/0x1b0
 vfs_setxattr+0xa0/0xb0
 setxattr+0x12c/0x1a0
 path_setxattr+0x8d/0xc0
 __x64_sys_setxattr+0x27/0x30
 do_syscall_64+0x60/0x250
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

In this case, @bs->bh stores '-EIO' actually.

Fixes: fb265c9c ("ext4: add ext4_sb_bread() to disambiguate ENOMEM cases")
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: stable@kernel.org # 2.6.19
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/1587628004-95123-1-git-send-email-jefflexu@linux.alibaba.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

When we are evicting inode with journalled data, we may race with
transaction commit in the following way:

CPU0					CPU1
jbd2_journal_commit_transaction()	evict(inode)
					  inode_io_list_del()
					  inode_wait_for_writeback()
  process BJ_Forget list
    __jbd2_journal_insert_checkpoint()
    __jbd2_journal_refile_buffer()
      __jbd2_journal_unfile_buffer()
        if (test_clear_buffer_jbddirty(bh))
          mark_buffer_dirty(bh)
	    __mark_inode_dirty(inode)
					  ext4_evict_inode(inode)
					    frees the inode

This results in use-after-free issues in the writeback code (or
the assertion added in the previous commit triggering).

Fix the problem by removing inode from writeback lists once all the page
cache is evicted and so inode cannot be added to writeback lists again.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200421085445.5731-4-jack@suse.czSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Ext4 needs to remove inode from writeback lists after it is out of
visibility of its journalling machinery (which can still dirty the
inode). Export inode_io_list_del() for it.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200421085445.5731-3-jack@suse.czSigned-off-by: Theodore Ts'o <tytso@mit.edu>

ext4_orphan_get() invokes ext4_read_inode_bitmap(), which returns a
reference of the specified buffer_head object to "bitmap_bh" with
increased refcnt.

When ext4_orphan_get() returns, local variable "bitmap_bh" becomes
invalid, so the refcount should be decreased to keep refcount balanced.

The reference counting issue happens in one exception handling path of
ext4_orphan_get(). When ext4_iget() fails, the function forgets to
decrease the refcnt increased by ext4_read_inode_bitmap(), causing a
refcnt leak.

Fix this issue by calling brelse() when ext4_iget() fails.
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/1587618568-13418-1-git-send-email-xiyuyang19@fudan.edu.cnSigned-off-by: Theodore Ts'o <tytso@mit.edu>

If eh->eh_max is 0, EXT_MAX_EXTENT/INDEX would evaluate to unsigned
(-1) resulting in illegal memory accesses. Although there is no
consistent repro, we see that generic/019 sometimes crashes because of
this bug.

Ran gce-xfstests smoke and verified that there were no regressions.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20200421023959.20879-2-harshadshirwadkar@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org

Fix the following coccicheck warning:

fs/ext4/extents_status.c:1057:5-28: WARNING: Comparison to bool
fs/ext4/inode.c:2314:18-24: WARNING: Comparison to bool
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200420042918.19459-1-yanaijie@huawei.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

As new ext4_map_blocks() flags have been added, not all have gotten flag
bit to string translations to make tracepoint output more readable.
Fix that, and go one step further by adding a translation for the
EXT4_EX_NOCACHE flag as well.  The EXT4_EX_FORCE_CACHE flag can never
be set in a tracepoint in the current code, so there's no need to
bother with a translation for it right now.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200415203140.30349-3-enwlinux@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

The eofblocks code was removed in the 5.7 release by "ext4: remove
EOFBLOCKS_FL and associated code" (4337ecd1).  The ext4_map_blocks()
flag used to trigger it can now be removed as well.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200415203140.30349-2-enwlinux@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Fixed an if statement where braces were not needed.

Link: https://lore.kernel.org/r/20200416141456.1089-1-carlosteniswarrior@gmail.comSigned-off-by: Carlos Guerrero Álvarez <carlosteniswarrior@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>

We can use the ext4_has_feature_bigalloc() function directly to check
bigalloc feature and the variable has_bigalloc is reduncant, so remove
it.
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/1586935542-29588-1-git-send-email-kaixuxia@tencent.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

The DIOREAD_NOLOCK flag has been cleared when doing the test_opt
that is meaningless, so remove the unnecessary test_opt for DIOREAD_NOLOCK.
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Link: https://lore.kernel.org/r/1586751862-19437-1-git-send-email-kaixuxia@tencent.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Pull more btrfs fixes from David Sterba:
 "A few more stability fixes, minor build warning fixes and git url
  fixup:

   - fix partial loss of prealloc extent past i_size after fsync

   - fix potential deadlock due to wrong transaction handle passing via
     journal_info

   - fix gcc 4.8 struct intialization warning

   - update git URL in MAINTAINERS entry"

* tag 'for-5.7-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  MAINTAINERS: btrfs: fix git repo URL
  btrfs: fix gcc-4.8 build warning for struct initializer
  btrfs: transaction: Avoid deadlock due to bad initialization timing of fs_info::journal_info
  btrfs: fix partial loss of prealloc extent past i_size after fsync

Pull IOMMU fixes from Joerg Roedel:

 - Fix a memory leak when dev_iommu gets freed and a sub-pointer does
   not

 - Build dependency fixes for Mediatek, spapr_tce, and Intel IOMMU
   driver

 - Export iommu_group_get_for_dev() only for GPLed modules

 - Fix AMD IOMMU interrupt remapping when x2apic is enabled

 - Fix error path in the QCOM IOMMU driver probe function

* tag 'iommu-fixes-v5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/qcom: Fix local_base status check
  iommu: Properly export iommu_group_get_for_dev()
  iommu/vt-d: Use right Kconfig option name
  iommu/amd: Fix legacy interrupt remapping for x2APIC-enabled system
  iommu: spapr_tce: Disable compile testing to fix build on book3s_32 config
  iommu/mediatek: Fix MTK_IOMMU dependencies
  iommu: Fix the memory leak in dev_iommu_free()