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    "id": 2216834,
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    "project": {
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        "name": "Linux ext4 filesystem development",
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    "msgid": "<20260327102939.1095257-1-yi.zhang@huaweicloud.com>",
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    "date": "2026-03-27T10:29:26",
    "name": "[v4,00/13] ext4: refactor partial block zero-out for iomap conversion",
    "submitter": {
        "id": 85428,
        "url": "http://patchwork.ozlabs.org/api/people/85428/?format=api",
        "name": "Zhang Yi",
        "email": "yi.zhang@huaweicloud.com"
    },
    "mbox": "http://patchwork.ozlabs.org/project/linux-ext4/cover/20260327102939.1095257-1-yi.zhang@huaweicloud.com/mbox/",
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            "url": "http://patchwork.ozlabs.org/api/series/497742/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/linux-ext4/list/?series=497742",
            "date": "2026-03-27T10:29:26",
            "name": "ext4: refactor partial block zero-out for iomap conversion",
            "version": 4,
            "mbox": "http://patchwork.ozlabs.org/series/497742/mbox/"
        }
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        "From": "Zhang Yi <yi.zhang@huaweicloud.com>",
        "To": "linux-ext4@vger.kernel.org",
        "Cc": "linux-fsdevel@vger.kernel.org,\n\tlinux-kernel@vger.kernel.org,\n\ttytso@mit.edu,\n\tadilger.kernel@dilger.ca,\n\tjack@suse.cz,\n\tojaswin@linux.ibm.com,\n\tritesh.list@gmail.com,\n\tlibaokun@linux.alibaba.com,\n\tyi.zhang@huawei.com,\n\tyi.zhang@huaweicloud.com,\n\tyizhang089@gmail.com,\n\tyangerkun@huawei.com,\n\tyukuai@fnnas.com",
        "Subject": "[PATCH v4 00/13] ext4: refactor partial block zero-out for iomap\n conversion",
        "Date": "Fri, 27 Mar 2026 18:29:26 +0800",
        "Message-ID": "<20260327102939.1095257-1-yi.zhang@huaweicloud.com>",
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    },
    "content": "From: Zhang Yi <yi.zhang@huawei.com>\n\nChanges since v3:\n - In patch 04, fix the comments of ext4_block_zero_range().\n - Add patch 09, ensure zeroed partial blocks are persisted in SYNC mode\n   for ext4_punch_hole() and ext4_zero_range(), This can resolve the\n   breaks in the guarantee of data-ordered mode caused by patch 05, as\n   pointed out by Sashiko.\n - Add patch 10, unify the inconsistent SYNC mode checks in all\n   fallocate paths.\n - In patch 12, fix two issues related to updating the file size in\n   error paths, as pointed out by Sashiko.\n\nChanges since v2:\n - Drop patch 02 in v2 because it will not be used in the later iomap\n   conversion.\n - In patch 08, modify ext4_alloc_file_blocks() to zero out EOF block\n   when new_size is larger than old_size, preventing the exposure of\n   stale data when the user performs fallocate starting within the\n   old_size. This was pointed out by Sashiko.\n - In patch 08, add checks for the return value of\n   ext4_block_zero_eof().\n - Add patches 09 and 10, move pagecache_isize_extended() out of an\n   active journal handle as well to prevent opposite lock ordering.\n   This was pointed out by Sashiko.\n - In patch 11, add a check for IOCB_NOWAIT, which was also pointed out\n   by Sashiko.\n\nChanges since v1:\n - In patch 04, rename ext4_block_get_zero_range() to\n   ext4_load_tail_bh() and drop the unused 'length' parameter as Jan\n   suggested.\n - In patch 06, modify the commit message, add another reason to drop\n   data=ordered mode when zeroing partial blocks in ext4_punch_hole()\n   and ext4_punch_hole() as Jan pointed out.\n - In patch 10, modify the commit message, explain the race condition\n   between the buffered write and mmap write that pointed out by Jan.\n - Collect reviewed tags from Jan.\n\nv3: https://lore.kernel.org/linux-ext4/20260326111054.907252-1-yi.zhang@huaweicloud.com/\nv2: https://lore.kernel.org/linux-ext4/20260325072850.3997161-1-yi.zhang@huaweicloud.com/\nv1: https://lore.kernel.org/linux-ext4/20260310014101.4140698-1-yi.zhang@huaweicloud.com/\n\nOriginal cover letter:\n\nThis patch series extracted from my iomap conversion v2 series[1]. It\nrefactors the ext4 zero partial block code path in preparation for\nconverting buffered I/O to the iomap infrastructure. The main changes\nare:\n\n[1] https://lore.kernel.org/linux-ext4/20260203062523.3869120-1-yi.zhang@huawei.com/\n\n1. Introduce ext4_block_zero_eof(): Extend and rename\n   ext4_block_truncate_page() to handle post-EOF partial block zeroing\n   for both append writes and truncate operations.\n2. Separate ordered data handling: Move data=ordered mode handling from\n   __ext4_block_zero_page_range to ext4_block_zero_eof(). Only truncate\n   and post-EOF append write/fallocate paths need ordered data mode,\n   hole punching and zero range paths don't need ordered data handling.\n3. Split journal mode handling: Extract\n   ext4_block_journalled_zero_range() from\n   __ext4_block_zero_page_range() for data=journal mode, leaving\n   ext4_block_do_zero_range() for data=ordered/writeback modes.\n4. Refactor ext4_alloc_file_blocks(): Change parameters to loff_t byte\n   granularity to simplify callers and prepares removing the zero call\n   from the allocation loop for unaligned append writes.\n5. Remove handle parameters: Stop passing handle_t * to zero functions.\n   Make ext4_block_journalled_zero_range() start its own handle, and\n   move zero operations outside active handles. This is required because\n   iomap uses \"folio lock -> transaction start\" lock ordering, opposite\n   to the current lock ordering.\n6. Centralize zeroing in ext4_write_checks(): Move all post-EOF partial\n   block zeroing to ext4_write_checks() so it applies to both regular\n   buffered writes and the upcoming iomap path.\n\nThanks\nYi.\n\nZhang Yi (13):\n  ext4: add did_zero output parameter to ext4_block_zero_page_range()\n  ext4: rename and extend ext4_block_truncate_page()\n  ext4: factor out journalled block zeroing range\n  ext4: rename ext4_block_zero_page_range() to ext4_block_zero_range()\n  ext4: move ordered data handling out of ext4_block_do_zero_range()\n  ext4: remove handle parameters from zero partial block functions\n  ext4: pass allocate range as loff_t to ext4_alloc_file_blocks()\n  ext4: move zero partial block range functions out of active handle\n  ext4: ensure zeroed partial blocks are persisted in SYNC mode\n  ext4: unify SYNC mode checks in fallocate paths\n  ext4: remove ctime/mtime update from ext4_alloc_file_blocks()\n  ext4: move pagecache_isize_extended() out of active handle\n  ext4: zero post-EOF partial block before appending write\n\n fs/ext4/ext4.h    |   5 +-\n fs/ext4/extents.c | 163 ++++++++++++++-------------\n fs/ext4/file.c    |  17 +++\n fs/ext4/inode.c   | 273 +++++++++++++++++++++++++++++-----------------\n 4 files changed, 278 insertions(+), 180 deletions(-)"
}