[ Upstream commit 29d47d00 ]

If we failed to allocate the data extent(s) for the inode space cache, we
were bailing out without releasing the previously reserved metadata. This
was triggering the following warnings when unmounting a filesystem:

  $ cat -n fs/btrfs/inode.c
  (...)
  9268  void btrfs_destroy_inode(struct inode *inode)
  9269  {
  (...)
  9276          WARN_ON(BTRFS_I(inode)->block_rsv.reserved);
  9277          WARN_ON(BTRFS_I(inode)->block_rsv.size);
  (...)
  9281          WARN_ON(BTRFS_I(inode)->csum_bytes);
  9282          WARN_ON(BTRFS_I(inode)->defrag_bytes);
  (...)

Several fstests test cases triggered this often, such as generic/083,
generic/102, generic/172, generic/269 and generic/300 at least, producing
stack traces like the following in dmesg/syslog:

  [82039.079546] WARNING: CPU: 2 PID: 13167 at fs/btrfs/inode.c:9276 btrfs_destroy_inode+0x203/0x270 [btrfs]
  (...)
  [82039.081543] CPU: 2 PID: 13167 Comm: umount Tainted: G        W         5.2.0-rc4-btrfs-next-50 #1
  [82039.081912] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
  [82039.082673] RIP: 0010:btrfs_destroy_inode+0x203/0x270 [btrfs]
  (...)
  [82039.083913] RSP: 0018:ffffac0b426a7d30 EFLAGS: 00010206
  [82039.084320] RAX: ffff8ddf77691158 RBX: ffff8dde29b34660 RCX: 0000000000000002
  [82039.084736] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8dde29b34660
  [82039.085156] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000
  [82039.085578] R10: ffffac0b426a7c90 R11: ffffffffb9aad768 R12: ffffac0b426a7db0
  [82039.086000] R13: ffff8ddf5fbec0a0 R14: dead000000000100 R15: 0000000000000000
  [82039.086416] FS:  00007f8db96d12c0(0000) GS:ffff8de036b00000(0000) knlGS:0000000000000000
  [82039.086837] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [82039.087253] CR2: 0000000001416108 CR3: 00000002315cc001 CR4: 00000000003606e0
  [82039.087672] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [82039.088089] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [82039.088504] Call Trace:
  [82039.088918]  destroy_inode+0x3b/0x70
  [82039.089340]  btrfs_free_fs_root+0x16/0xa0 [btrfs]
  [82039.089768]  btrfs_free_fs_roots+0xd8/0x160 [btrfs]
  [82039.090183]  ? wait_for_completion+0x65/0x1a0
  [82039.090607]  close_ctree+0x172/0x370 [btrfs]
  [82039.091021]  generic_shutdown_super+0x6c/0x110
  [82039.091427]  kill_anon_super+0xe/0x30
  [82039.091832]  btrfs_kill_super+0x12/0xa0 [btrfs]
  [82039.092233]  deactivate_locked_super+0x3a/0x70
  [82039.092636]  cleanup_mnt+0x3b/0x80
  [82039.093039]  task_work_run+0x93/0xc0
  [82039.093457]  exit_to_usermode_loop+0xfa/0x100
  [82039.093856]  do_syscall_64+0x162/0x1d0
  [82039.094244]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [82039.094634] RIP: 0033:0x7f8db8fbab37
  (...)
  [82039.095876] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
  [82039.096290] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37
  [82039.096700] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240
  [82039.097110] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015
  [82039.097522] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64
  [82039.097937] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0
  [82039.098350] irq event stamp: 0
  [82039.098750] hardirqs last  enabled at (0): [<0000000000000000>] 0x0
  [82039.099150] hardirqs last disabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00
  [82039.099545] softirqs last  enabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00
  [82039.099925] softirqs last disabled at (0): [<0000000000000000>] 0x0
  [82039.100292] ---[ end trace f2521afa616ddccc ]---
  [82039.100707] WARNING: CPU: 2 PID: 13167 at fs/btrfs/inode.c:9277 btrfs_destroy_inode+0x1ac/0x270 [btrfs]
  (...)
  [82039.103050] CPU: 2 PID: 13167 Comm: umount Tainted: G        W         5.2.0-rc4-btrfs-next-50 #1
  [82039.103428] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
  [82039.104203] RIP: 0010:btrfs_destroy_inode+0x1ac/0x270 [btrfs]
  (...)
  [82039.105461] RSP: 0018:ffffac0b426a7d30 EFLAGS: 00010206
  [82039.105866] RAX: ffff8ddf77691158 RBX: ffff8dde29b34660 RCX: 0000000000000002
  [82039.106270] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8dde29b34660
  [82039.106673] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000
  [82039.107078] R10: ffffac0b426a7c90 R11: ffffffffb9aad768 R12: ffffac0b426a7db0
  [82039.107487] R13: ffff8ddf5fbec0a0 R14: dead000000000100 R15: 0000000000000000
  [82039.107894] FS:  00007f8db96d12c0(0000) GS:ffff8de036b00000(0000) knlGS:0000000000000000
  [82039.108309] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [82039.108723] CR2: 0000000001416108 CR3: 00000002315cc001 CR4: 00000000003606e0
  [82039.109146] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [82039.109567] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [82039.109989] Call Trace:
  [82039.110405]  destroy_inode+0x3b/0x70
  [82039.110830]  btrfs_free_fs_root+0x16/0xa0 [btrfs]
  [82039.111257]  btrfs_free_fs_roots+0xd8/0x160 [btrfs]
  [82039.111675]  ? wait_for_completion+0x65/0x1a0
  [82039.112101]  close_ctree+0x172/0x370 [btrfs]
  [82039.112519]  generic_shutdown_super+0x6c/0x110
  [82039.112988]  kill_anon_super+0xe/0x30
  [82039.113439]  btrfs_kill_super+0x12/0xa0 [btrfs]
  [82039.113861]  deactivate_locked_super+0x3a/0x70
  [82039.114278]  cleanup_mnt+0x3b/0x80
  [82039.114685]  task_work_run+0x93/0xc0
  [82039.115083]  exit_to_usermode_loop+0xfa/0x100
  [82039.115476]  do_syscall_64+0x162/0x1d0
  [82039.115863]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [82039.116254] RIP: 0033:0x7f8db8fbab37
  (...)
  [82039.117463] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
  [82039.117882] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37
  [82039.118330] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240
  [82039.118743] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015
  [82039.119159] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64
  [82039.119574] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0
  [82039.119987] irq event stamp: 0
  [82039.120387] hardirqs last  enabled at (0): [<0000000000000000>] 0x0
  [82039.120787] hardirqs last disabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00
  [82039.121182] softirqs last  enabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00
  [82039.121563] softirqs last disabled at (0): [<0000000000000000>] 0x0
  [82039.121933] ---[ end trace f2521afa616ddccd ]---
  [82039.122353] WARNING: CPU: 2 PID: 13167 at fs/btrfs/inode.c:9278 btrfs_destroy_inode+0x1bc/0x270 [btrfs]
  (...)
  [82039.124606] CPU: 2 PID: 13167 Comm: umount Tainted: G        W         5.2.0-rc4-btrfs-next-50 #1
  [82039.125008] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
  [82039.125801] RIP: 0010:btrfs_destroy_inode+0x1bc/0x270 [btrfs]
  (...)
  [82039.126998] RSP: 0018:ffffac0b426a7d30 EFLAGS: 00010202
  [82039.127399] RAX: ffff8ddf77691158 RBX: ffff8dde29b34660 RCX: 0000000000000002
  [82039.127803] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8dde29b34660
  [82039.128206] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000
  [82039.128611] R10: ffffac0b426a7c90 R11: ffffffffb9aad768 R12: ffffac0b426a7db0
  [82039.129020] R13: ffff8ddf5fbec0a0 R14: dead000000000100 R15: 0000000000000000
  [82039.129428] FS:  00007f8db96d12c0(0000) GS:ffff8de036b00000(0000) knlGS:0000000000000000
  [82039.129846] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [82039.130261] CR2: 0000000001416108 CR3: 00000002315cc001 CR4: 00000000003606e0
  [82039.130684] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [82039.131142] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [82039.131561] Call Trace:
  [82039.131990]  destroy_inode+0x3b/0x70
  [82039.132417]  btrfs_free_fs_root+0x16/0xa0 [btrfs]
  [82039.132844]  btrfs_free_fs_roots+0xd8/0x160 [btrfs]
  [82039.133262]  ? wait_for_completion+0x65/0x1a0
  [82039.133688]  close_ctree+0x172/0x370 [btrfs]
  [82039.134157]  generic_shutdown_super+0x6c/0x110
  [82039.134575]  kill_anon_super+0xe/0x30
  [82039.134997]  btrfs_kill_super+0x12/0xa0 [btrfs]
  [82039.135415]  deactivate_locked_super+0x3a/0x70
  [82039.135832]  cleanup_mnt+0x3b/0x80
  [82039.136239]  task_work_run+0x93/0xc0
  [82039.136637]  exit_to_usermode_loop+0xfa/0x100
  [82039.137029]  do_syscall_64+0x162/0x1d0
  [82039.137418]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [82039.137812] RIP: 0033:0x7f8db8fbab37
  (...)
  [82039.139059] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
  [82039.139475] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37
  [82039.139890] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240
  [82039.140302] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015
  [82039.140719] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64
  [82039.141138] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0
  [82039.141597] irq event stamp: 0
  [82039.142043] hardirqs last  enabled at (0): [<0000000000000000>] 0x0
  [82039.142443] hardirqs last disabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00
  [82039.142839] softirqs last  enabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00
  [82039.143220] softirqs last disabled at (0): [<0000000000000000>] 0x0
  [82039.143588] ---[ end trace f2521afa616ddcce ]---
  [82039.167472] WARNING: CPU: 3 PID: 13167 at fs/btrfs/extent-tree.c:10120 btrfs_free_block_groups+0x30d/0x460 [btrfs]
  (...)
  [82039.173800] CPU: 3 PID: 13167 Comm: umount Tainted: G        W         5.2.0-rc4-btrfs-next-50 #1
  [82039.174847] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
  [82039.177031] RIP: 0010:btrfs_free_block_groups+0x30d/0x460 [btrfs]
  (...)
  [82039.180397] RSP: 0018:ffffac0b426a7dd8 EFLAGS: 00010206
  [82039.181574] RAX: ffff8de010a1db40 RBX: ffff8de010a1db40 RCX: 0000000000170014
  [82039.182711] RDX: ffff8ddff4380040 RSI: ffff8de010a1da58 RDI: 0000000000000246
  [82039.183817] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000
  [82039.184925] R10: ffff8de036404380 R11: ffffffffb8a5ea00 R12: ffff8de010a1b2b8
  [82039.186090] R13: ffff8de010a1b2b8 R14: 0000000000000000 R15: dead000000000100
  [82039.187208] FS:  00007f8db96d12c0(0000) GS:ffff8de036b80000(0000) knlGS:0000000000000000
  [82039.188345] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [82039.189481] CR2: 00007fb044005170 CR3: 00000002315cc006 CR4: 00000000003606e0
  [82039.190674] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [82039.191829] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [82039.192978] Call Trace:
  [82039.194160]  close_ctree+0x19a/0x370 [btrfs]
  [82039.195315]  generic_shutdown_super+0x6c/0x110
  [82039.196486]  kill_anon_super+0xe/0x30
  [82039.197645]  btrfs_kill_super+0x12/0xa0 [btrfs]
  [82039.198696]  deactivate_locked_super+0x3a/0x70
  [82039.199619]  cleanup_mnt+0x3b/0x80
  [82039.200559]  task_work_run+0x93/0xc0
  [82039.201505]  exit_to_usermode_loop+0xfa/0x100
  [82039.202436]  do_syscall_64+0x162/0x1d0
  [82039.203339]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [82039.204091] RIP: 0033:0x7f8db8fbab37
  (...)
  [82039.206360] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
  [82039.207132] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37
  [82039.207906] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240
  [82039.208621] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015
  [82039.209285] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64
  [82039.209984] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0
  [82039.210642] irq event stamp: 0
  [82039.211306] hardirqs last  enabled at (0): [<0000000000000000>] 0x0
  [82039.211971] hardirqs last disabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00
  [82039.212643] softirqs last  enabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00
  [82039.213304] softirqs last disabled at (0): [<0000000000000000>] 0x0
  [82039.213875] ---[ end trace f2521afa616ddccf ]---

Fix this by releasing the reserved metadata on failure to allocate data
extent(s) for the inode cache.

Fixes: 69fe2d75 ("btrfs: make the delalloc block rsv per inode")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>