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authorBreno Leitao <leitao@debian.org>2026-08-05 07:52:36 -0700
committerTejun Heo <tj@kernel.org>2026-08-10 11:47:20 -1000
commita5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656 (patch)
tree39f5b258386e1127d253d293194e9a2991bf3c34 /Documentation/filesystems/ext4/blockmap.rst
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workqueue: skip the node_nr_active update for non-unbound workqueuesgrafted
apply_wqattrs_commit() updates node_nr_active->max unconditionally. wq->node_nr_active[] is only allocated for unbound workqueues, so guard the call before per-cpu workqueues start using this path. No functional change: only unbound workqueues reach apply_wqattrs_*() today. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Tejun Heo <tj@kernel.org>
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+.. SPDX-License-Identifier: GPL-2.0
+
++---------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+| i.i_block Offset | Where It Points |
++=====================+==============================================================================================================================================================================================================================+
+| 0 to 11 | Direct map to file blocks 0 to 11. |
++---------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+| 12 | Indirect block: (file blocks 12 to (``$block_size`` / 4) + 11, or 12 to 1035 if 4KiB blocks) |
+| | |
+| | +------------------------------+--------------------------------------------------------------------+ |
+| | | Indirect Block Offset | Where It Points | |
+| | +==============================+====================================================================+ |
+| | | 0 to (``$block_size`` / 4) | Direct map to (``$block_size`` / 4) blocks (1024 if 4KiB blocks) | |
+| | +------------------------------+--------------------------------------------------------------------+ |
++---------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+| 13 | Double-indirect block: (file blocks ``$block_size``/4 + 12 to (``$block_size`` / 4) ^ 2 + (``$block_size`` / 4) + 11, or 1036 to 1049611 if 4KiB blocks) |
+| | |
+| | +--------------------------------+---------------------------------------------------------------------------------------------------------+ |
+| | | Double Indirect Block Offset | Where It Points | |
+| | +================================+=========================================================================================================+ |
+| | | 0 to (``$block_size`` / 4) | Map to (``$block_size`` / 4) indirect blocks (1024 if 4KiB blocks) | |
+| | | | | |
+| | | | +------------------------------+--------------------------------------------------------------------+ | |
+| | | | | Indirect Block Offset | Where It Points | | |
+| | | | +==============================+====================================================================+ | |
+| | | | | 0 to (``$block_size`` / 4) | Direct map to (``$block_size`` / 4) blocks (1024 if 4KiB blocks) | | |
+| | | | +------------------------------+--------------------------------------------------------------------+ | |
+| | +--------------------------------+---------------------------------------------------------------------------------------------------------+ |
++---------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+| 14 | Triple-indirect block: (file blocks (``$block_size`` / 4) ^ 2 + (``$block_size`` / 4) + 12 to (``$block_size`` / 4) ^ 3 + (``$block_size`` / 4) ^ 2 + (``$block_size`` / 4) + 12, or 1049612 to 1074791436 if 4KiB blocks) |
+| | |
+| | +--------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------+ |
+| | | Triple Indirect Block Offset | Where It Points | |
+| | +================================+================================================================================================================================================+ |
+| | | 0 to (``$block_size`` / 4) | Map to (``$block_size`` / 4) double indirect blocks (1024 if 4KiB blocks) | |
+| | | | | |
+| | | | +--------------------------------+---------------------------------------------------------------------------------------------------------+ | |
+| | | | | Double Indirect Block Offset | Where It Points | | |
+| | | | +================================+=========================================================================================================+ | |
+| | | | | 0 to (``$block_size`` / 4) | Map to (``$block_size`` / 4) indirect blocks (1024 if 4KiB blocks) | | |
+| | | | | | | | |
+| | | | | | +------------------------------+--------------------------------------------------------------------+ | | |
+| | | | | | | Indirect Block Offset | Where It Points | | | |
+| | | | | | +==============================+====================================================================+ | | |
+| | | | | | | 0 to (``$block_size`` / 4) | Direct map to (``$block_size`` / 4) blocks (1024 if 4KiB blocks) | | | |
+| | | | | | +------------------------------+--------------------------------------------------------------------+ | | |
+| | | | +--------------------------------+---------------------------------------------------------------------------------------------------------+ | |
+| | +--------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------+ |
++---------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+