fs_bdev_file_open_by_path(9)

✨ fs_bdev_file_open_by_path(9) ✨

okay so bestie, welcome to the Kernel API Manual 💖 this one is literally the "hey block device, meet your new superblock" page and it's giving matchmaker energy fr fr 🎀

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🌸 NAME 🌸

fs_bdev_file_open_by_path — claim a block device on behalf of a superblock 🫶

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🦋 SYNOPSIS 🦋

struct file * fs_bdev_file_open_by_path (const char *path , blk_mode_t
mode , void *holder , struct super_block *sb );

like, that's the whole vibe. four args, one struct file * back at you (or a plot twist, see RETURN below 😭) ✨

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💅 ARGUMENTS 💅

• path — path to the block device. yep, just the path. go find your blkdev queen 👑
• mode — open mode. how you're coming at it, basically 🌈
• holder — block-layer exclusivity token. and no, not just anything — it's a superblock, or the file_system_type when the device may be shared by several superblocks of that type. iykyk 💀
• sb — superblock to drive fs_holder_ops events for. this is the main character of this whole operation ngl ⭐

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💖 DESCRIPTION 💖

so what it does is: open the block device at path with fs_holder_ops and register that sb uses it — so device removal/sync/freeze/thaw are propagated to sb (and any other superblock sharing the device). the way that one call sets up the whole group chat 😭🔥

⚠️ important bestie: this must be paired with fs_bdev_file_release. don't leave it hanging, that's so not slay 🙈

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🎀 RETURN 🎀

an opened block-device file or an ERR_PTR. so like, either a cute file or a sad little error pointer — vibe check accordingly 💅

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🌟 SEE ALSO 🌟

all the siblings and cousins and extended family, we love a big family tree 🧚‍♀️:

Kernel file ./fs/super.c — plus: super_lock(9), alloc_super(9), deactivate_locked_super(9), deactivate_super(9), grab_super(9), retire_super(9), generic_shutdown_super(9), sget_fc(9), iterate_supers_type(9), reconfigure_super(9), emergency_thaw_all(9), get_anon_bdev(9), sget_dev(9), fs_bdev_freeze(9), fs_bdev_thaw(9), fs_bdev_file_open_by_dev(9), fs_bdev_unregister(9), fs_bdev_file_release(9), get_tree_bdev_flags(9), get_tree_bdev(9), vfs_get_tree(9), sb_wait_write(9), freeze_super(9), thaw_super(9)

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and that's the page!! 🍓 she lives in ./fs, she's stamped October 2026, and she answers to the name fs_bdev_file_open_by_path(9) — periodt, love u, go pair your release calls 💜🎀✨