pcache_cache_flush(9)

💖 pcache_cache_flush(9) 💖

bestie, welcome to the Kernel API Manual corner where kernel cache internals get the group-chat treatment. this one is pcache_cache_flush(9), and she is iconic for a reason.

✨ NAME ✨

pcache_cache_flush — flush all ksets to persist any pending cache data. that's the whole name, no cap.

🦋 SYNOPSIS 🦋

int pcache_cache_flush (struct pcache_cache *cache );

🎀 ARGUMENTS 🎀

• cache — pointer to the cache structure. that's the one thing you're handing over, bestie.

💅 DESCRIPTION 💅

okay so here's the tea: this function iterates through all the ksets associated with the cache you passed in, and makes sure any data marked for persistence gets written to media. for each kset, it acquires the kset lock, then invokes cache_kset_close, which handles the persistence logic for that kset.

if cache_kset_close encounters an error, the function exits immediately with the respective error code. that means the flush operation does not proceed to subsequent ksets — it stops right there, preventing the flush operation from proceeding to subsequent ksets. periodt.

🌈 SEE ALSO 🌈

the whole squad is:

• Kernel file ./drivers/md/dm-pcache/cache_req.c
• cache_data_alloc(9)
• miss_read_end_req(9)
• submit_cache_miss_req(9)
• read_walk_finally(9)
• cache_read(9)

xoxo bestie — source/version is ./drivers/md/dm-pcache, and the date on this cutie is October 2026. 💜