STRUCT JBD2_INODE(9)

💖 NAME 💖

okay so bestie, welcome to struct jbd2_inode(9) from the Kernel API Manual — and it's giving “the little struct that keeps ordered-mode inodes linked inside a transaction so commit can sync them” energy. 💅

The jbd_inode type — yes, that's literally how the NAME text says it — is the structure linking inodes in ordered mode present in a transaction so that we can sync them during commit. ✨

🦋 SYNOPSIS 🦋

       struct jbd2_inode {
           transaction_t *i_transaction;
           transaction_t *i_next_transaction;
           struct list_head i_list;
           struct inode *i_vfs_inode;
           unsigned long i_flags;
           pgoff_t i_dirty_start_page;
           pgoff_t i_dirty_end_page;
        };

💅 Members 💅

• i_transaction — which transaction does this inode belong to? Either the running transaction or the committing one. Tagged [j_list_lock]. 👑
• i_next_transaction — pointer to the running transaction modifying the inode's data in case there is already a committing transaction touching it. Tagged [j_list_lock]. 🌀
• i_list — list of inodes in the i_transaction. Tagged [j_list_lock]. 🎀
• i_vfs_inode — the VFS inode this inode belongs to; [constant for lifetime of structure]. 🦋
• i_flags — flags of the inode. Tagged [j_list_lock]. 🚩
• i_dirty_start_page — dirty range start in PAGE_SIZE units. The dirty range is empty if i_dirty_start_page is greater than or equal to i_dirty_end_page. Tagged [j_list_lock]. 🌸
• i_dirty_end_page — dirty range end in PAGE_SIZE units (exclusive). Tagged [j_list_lock]. 🔥

🌈 SEE ALSO 🌈

the manpage points you at the kernel file ./include/linux/jbd2.h, plus these iconic little references:

• handle_t(9)
• journal_t(9)
• struct jbd2_journal_handle(9)
• struct journal_s(9)

source/version: ./include/linux · date: October 2026 · page: struct jbd2_inode(9) — bye bestie, go sync those inodes 💖🦋