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ch9-pv1-the-extended-filesystem-family
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- 2. ● Block Layout ●Indirect/Extent ● Mount Flow ● Operations ● Journal
- 3. superblock group descriptors reserved gdtblocks block bitmaps(all groups) inode bitmaps(all groups) inode table(group 0) inode table(group 1) inode table(group 15) Block Layout meta blocks data blocks block group(32768 blocks = 128M)
- 4. Block Layout block group#0 #1 #15#2 #3 flex group 128M * 16 = 2G
- 5. Block Layout #1 #3 flexgroup #0 #15#2 #17 #19 flex group #31#18#16 #33 #35 flex group #47#34#32 #49 #51 flex group #50#48
- 6. data data blk# blk# blk# blk# blk# blk# Indirect/Extent ei data blk# blk# blk# data 1024 blk# blk# blk# blk# blk# blk# data blk# blk# blk# blk# blk# blk# blk# blk# blk# data data data blk# blk# blk# blk# blk# blk# data data data data 12 max = 12+ 1024 + 1024^2 + 1024^3 blk# blk# blk# indirect double indirect triple indirect 1024^2
- 7. Indirect/Extent ei idx idx hdr idx hdr ext hdr ext hdr ext hdr data data data data data data data data mi n n n pagepage page page page page page page storage memory
- 8. Indirect/Extent ei idx idx hdr idx hdr ext hdr ext hdr ext hdr data data data data data data data data storage file dir abcde dirent dirent dirent dirent direntdirent file/dir 都可以有多個 block 不保證連續 各自紀錄 data/dirent
- 9. Mount Flow memory ext4@storage *. 建mountext4m s i i i i i i root journal i i
- 10. Mount Flow memory ext4@storage *. 建mount *. 建 sb/sbi, 根據讀入的 es 設定 ext4m s s i i i i i i root journal i i
- 11. Mount Flow memory ext4@storage *. 建mount *. 建 sb/sbi, 根據讀入的 es 設定 *. 為 sb 安裝 sops ext4m s sop s i i i i i i root journal i i
- 12. Mount Flow memory ext4@storage *. 建mount *. 建 sb/sbi, 根據讀入的 es 設定 *. 為 sb 安裝 sops *. 載入 journal ext4m s sop s i i i i i i root journal journal i i
- 13. Mount Flow memory ext4@storage *. 建mount *. 建 sb/sbi, 根據讀入的 es 設定 *. 為 sb 安裝 sops *. 載入 journal *. 建 root inode/dentry fop iopi d “/” ext4m s sop s i i i i i i root journal journal i i
- 14. Mount Flow memory ext4@storage *. 建mount *. 建 sb/sbi, 根據讀入的 es 設定 *. 為 sb 安裝 sops *. 載入 journal *. 建 root inode/dentry *. 串入 parent mount s i i i i i i root journal journal i i fopiopi “/”d rootfsm fopiopi d “aaa” ext4m fopiopi d “/”
- 15. Operations(lookup) e.g. /home/pi/Desktop memory ext4@storage s pi dirent dirent direntdirent dirent dirent pi d “pi” fop iopi
- 16. Operations(lookup) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry memory ext4@storage s pi dirent dirent dirent dirent dirent dirent pi d “pi” fop iopi d “Desktop”
- 17. Operations(lookup) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup memory ext4@storage s pi dirent dirent dirent dirent dirent dirent pi d “pi” fop iopi ext4_lookup d “Desktop”
- 18. Operations(lookup) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup *. 根據 name 找 dirent( 獲取 ino) memory ext4@storage s pi dirent dirent dirent dirent dirent dirent pi .inode = # .name = “Desktop” d “pi” fop iopi ext4_lookup d “Desktop”
- 19. Operations(lookup) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup *. 根據 name 找 dirent( 獲取 ino) *. 根據 ino 對應 ext4 inode 建 inode memory ext4@storage s i pi dirent dirent dirent dirent dirent dirent pi Desktop .inode = # .name = “Desktop” d “pi” fop iopi ext4_lookup fop iopi d “Desktop”
- 20. Operations(lookup) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup *. 根據 name 找 dirent( 獲取 ino) *. 根據 ino 對應 ext4 inode 建 inode *. 關聯 dentry & inode *. 把 dentry 加入 table memory ext4@storage s i pi dirent dirent dirent dirent dirent dirent pi Desktop .inode = # .name = “Desktop” d “pi” fop iopi ext4_lookup fop iopi d “Desktop”
- 21. Operations(mkdir) e.g. /home/pi/Desktop memory ext4@storage s i pi direntdirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi d “Desktop” s sop
- 22. Operations(mkdir) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi d “Desktop” s sop
- 23. Operations(mkdir) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup, 找無 memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi ext4_lookup d “Desktop” s sop
- 24. Operations(mkdir) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup, 找無 *. 執行 dir(pi) 自帶 ext4_mkdir memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi ext4_lookup d “Desktop” s sop ext4_mkdir
- 25. Operations(mkdir) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup, 找無 *. 執行 dir(pi) 自帶 ext4_mkdir +. 執行 sb 自帶 ext4_alloc_inode memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi ext4_lookup i d “Desktop” s sop ext4_alloc_inode ext4_mkdir
- 26. Operations(mkdir) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup, 找無 *. 執行 dir(pi) 自帶 ext4_mkdir +. 執行 sb 自帶 ext4_alloc_inode +. 為 inode 安裝 fop/iop memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi ext4_lookup fop iopi d “Desktop” s sop ext4_alloc_inode ext4_mkdir
- 27. Operations(mkdir) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup, 找無 *. 執行 dir(pi) 自帶 ext4_mkdir +. 執行 sb 自帶 ext4_alloc_inode +. 為 inode 安裝 fop/iop +. 準備 Desktop/ 內容 memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop dirent dirent Desktop d “pi” fop iopi ext4_lookup fop iopi d “Desktop” s sop ext4_alloc_inode ext4_mkdir
- 28. Operations(mkdir) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup, 找無 *. 執行 dir(pi) 自帶 ext4_mkdir +. 執行 sb 自帶 ext4_alloc_inode +. 為 inode 安裝 fop/iop +. 準備 Desktop/ 內容 +. 加入 pi/ memory ext4@storage s i pi dirent dirent dirent dirent dirent dirent pi Desktop dirent dirent Desktop d “pi” fop iopi ext4_lookup fop iopi d “Desktop” s sop ext4_alloc_inode ext4_mkdir
- 29. Operations(mkdir) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup, 找無 *. 執行 dir(pi) 自帶 ext4_mkdir +. 執行 sb 自帶 ext4_alloc_inode +. 為 inode 安裝 fop/iop +. 準備 Desktop/ 內容 +. 加入 pi/ +. 關連 dentry & inode memory ext4@storage s i pi dirent dirent dirent dirent dirent dirent pi Desktop dirent dirent Desktop d “pi” fop iopi ext4_lookup fop iopi d “Desktop” s sop ext4_alloc_inode ext4_mkdir
- 30. Operations(touch) e.g. /home/pi/Desktop *. 在table 找無 , 新建 dentry *. 執行 dir(pi) 自帶 ext4_lookup, 找無 *. 執行 dir(pi) 自帶 ext4_create +. 執行 sb 自帶 ext4_alloc_inode +. 為 inode 安裝 fop/iop/aop +. 準備 Desktop/ 內容 +. 加入 pi/ +. 關連 dentry & inode *. open & release memory ext4@storage s i pi dirent dirent dirent dirent dirent dirent pi Desktop dirent dirent Desktop d “pi” fop iopi ext4_lookup iopi d “Desktop” s sop ext4_alloc_inode ext4_mkdir aop fop ext4_file_open ext4_release_file
- 31. fop Operations(rm/rmdir) e.g. /home/pi/Desktop memory ext4@storage s i pi direntdirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi iopi d “Desktop” s sop dirent dirent dirent
- 32. fop Operations(rm/rmdir) e.g. /home/pi/Desktop *. 執行dir(pi) 自帶 unlink 或 rmdir memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi ext4_unlink iopi d “Desktop” s sop ext4_rmdir dirent dirent dirent
- 33. fop Operations(rm/rmdir) e.g. /home/pi/Desktop *. 執行dir(pi) 自帶 unlink 或 rmdir +. 從 dir(pi) 移除 de(Desktop) memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi ext4_unlink iopi d “Desktop” s sop ext4_rmdir dirent dirent
- 34. fop Operations(rm/rmdir) e.g. /home/pi/Desktop *. 執行dir(pi) 自帶 unlink 或 rmdir +. 從 dir(pi) 移除 de(Desktop) *. 執行 sb 自帶 ext4_evict_inode memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi ext4_unlink iopi d “Desktop” s sop ext4_evict_inode ext4_rmdir dirent dirent
- 35. fop Operations(rm/rmdir) e.g. /home/pi/Desktop *. 執行dir(pi) 自帶 unlink 或 rmdir +. 從 dir(pi) 移除 de(Desktop) *. 執行 sb 自帶 ext4_evict_inode +. 歸還 ext4 inode 的 data block memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi ext4_unlink iopi d “Desktop” s sop ext4_evict_inode ext4_rmdir
- 36. fop Operations(rm/rmdir) e.g. /home/pi/Desktop *. 執行dir(pi) 自帶 unlink 或 rmdir +. 從 dir(pi) 移除 de(Desktop) *. 執行 sb 自帶 ext4_evict_inode +. 歸還 ext4 inode 的 data block +. 歸還 ext4 inode 本身 memory ext4@storage s pi dirent dirent dirent dirent dirent pi Desktop d “pi” fop iopi ext4_unlink iopi d “Desktop” s sop ext4_evict_inode ext4_rmdir
- 37. fop Journal e.g. /home/pi/Desktop *. 執行dir(pi) 自帶 unlink 或 rmdir +. 從 dir(pi) 移除 de(Desktop) *. 執行 sb 自帶 ext4_evict_inode +. 歸還 ext4 inode 的 data block +. 歸還 ext4 inode 本身 memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi ext4_unlink iopi d “Desktop” s sop ext4_evict_inode ext4_rmdir abcde o x 未歸還 block/inode 造成 storage leak
- 38. fop Journal e.g. /home/pi/Desktop *. 執行dir(pi) 自帶 unlink 或 rmdir +. 從 dir(pi) 移除 de(Desktop) *. 執行 sb 自帶 ext4_evict_inode +. 歸還 ext4 inode 的 data block +. 歸還 ext4 inode 本身 memory ext4@storage s i pi dirent dirent dirent dirent dirent pi Desktop Desktop d “pi” fop iopi ext4_unlink iopi d “Desktop” s sop ext4_evict_inode ext4_rmdir abcde x o ext4 inode 被當 free, 配給新 file
- 39. Journal memory ext4@storage 1 2 journal *. 把 1stmeta 寫入 journal *. 把 2nd meta 寫入 journal *. 把 3rd meta 寫入 journal *. 把 1st meta 寫入 target *. 把 2nd meta 寫入 target *. 把 3rd meta 寫入 target 都未寫入 , 沒 consistent 問題 crash
- 40. Journal memory ext4@storage 1 2 journal *. 把 1stmeta 寫入 journal *. 把 2nd meta 寫入 journal *. 把 3rd meta 寫入 journal *. 把 1st meta 寫入 target *. 把 2nd meta 寫入 target *. 把 3rd meta 寫入 target 寫入部份 , 有 consistent 問題 *. 1st meta --> 捨棄 , 沒 consistent 問題 crash crash
- 41. Journal memory ext4@storage 1 2 journal *. 把 1stmeta 寫入 journal *. 把 2nd meta 寫入 journal *. 把 3rd meta 寫入 journal *. 把 1st meta 寫入 target *. 把 2nd meta 寫入 target *. 把 3rd meta 寫入 target 全部寫入 , 沒 consistent 問題 *. 1st meta *. 2nd meta *. 3rd meta --> 寫入 target, 也稱為 replay crash crash crash
- 42. Journal memory ext4@storage 1 2 journal *. 把 1stmeta 寫入 journal *. 把 2nd meta 寫入 journal *. 把 3rd meta 寫入 journal *. 把 1st meta 寫入 target *. 把 2nd meta 寫入 target *. 把 3rd meta 寫入 target 全部寫入 , revoke *. 1st meta *. 2nd meta *. 3rd meta --> revoke( 之後不會 replay) crash
- 43. Journal memory ext4@storage physical journal (journal@ext4) logical journal (writeback@ext4)(ordered@ext4) 1 2 1 2 journal 1 2 journal 1 2 journal 在 meta 前寫入