shmem_file_setup_with_mnt(9)

🌸 shmem_file_setup_with_mnt (9) — the kernel API manual, bestie edition 🎀

okay so picture this: you need a file. but not, like, a file file. no directory entry, no name on disk, just a vibe living rent-free in tmpfs. that's literally what this function does and honestly? iconic. it hands you back a struct file * that's already unlinked, chillin' in a tmpfs mount of your choosing. no cap. 💅

✨ NAME ✨

shmem_file_setup_with_mnt — get an unlinked file living in tmpfs 🫶

🌈 SYNOPSIS 🌈

struct file * shmem_file_setup_with_mnt (struct vfsmount *mnt , const
       char *name , loff_t size , vma_flags_t flags );

like, that's the whole signature. look at her go. 👑

💖 ARGUMENTS 💖

• mnt — the tmpfs mount where the file will be created. yes, you pick which mount. main character energy fr fr.
• name — name for dentry (to be seen in /proc/<pid>/maps). so it does have a name, it's just for looking pretty in maps, not for finding on disk. iykyk.
• size — size to be set for the file. the number. the whole lewk. 📏
• flags — VMA_NORESERVE_BIT suppresses pre-accounting of the entire object size. like, no reserving the whole thing up front, mmkay? 💀

🦋 SEE ALSO 🦋

• Kernel file ./mm/shmem.c
• shmem_recalc_inode(9)
• shmem_writeout(9)
• shmem_get_folio(9)
• shmem_kernel_file_setup(9)
• shmem_file_setup(9)
• shmem_zero_setup(9)
• shmem_zero_setup_desc(9)
• shmem_read_folio_gfp(9)

the whole shmem friend group!! go read them too, they're all serving. 🌸✨

ngl bestie, this one lives in ./mm, and it's dated October 2026. that's the source/version and date teas, so now you know. mwah 💋 🩷