linux/fs/logfs/logfs.h

736 lines
24 KiB

logfs: Propagate page parameter to __logfs_write_inode During GC LogFS has to rewrite each valid block to a separate segment. Rewrite operation reads data from an old segment and writes it to a newly allocated segment. Since every write operation changes data block pointers maintained in inode, inode should also be rewritten. In GC path to avoid AB-BA deadlock LogFS marks a page with PG_pre_locked in addition to locking the page (PG_locked). The page lock is ignored iff the page is pre-locked. LogFS uses a special file called segment file. The segment file maintains an 8 bytes entry for every segment. It keeps track of erase count, level etc. for every segment. Bad things happen with a segment belonging to the segment file is GCed ------------[ cut here ]------------ kernel BUG at /home/prasad/logfs/readwrite.c:297! invalid opcode: 0000 [#1] SMP Modules linked in: logfs joydev usbhid hid psmouse e1000 i2c_piix4 serio_raw [last unloaded: logfs] Pid: 20161, comm: mount Not tainted 3.1.0-rc3+ #3 innotek GmbH VirtualBox EIP: 0060:[<f809132a>] EFLAGS: 00010292 CPU: 0 EIP is at logfs_lock_write_page+0x6a/0x70 [logfs] EAX: 00000027 EBX: f73f5b20 ECX: c16007c8 EDX: 00000094 ESI: 00000000 EDI: e59be6e4 EBP: c7337b28 ESP: c7337b18 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 Process mount (pid: 20161, ti=c7336000 task=eb323f70 task.ti=c7336000) Stack: f8099a3d c7337b24 f73f5b20 00001002 c7337b50 f8091f6d f8099a4d f80994e4 00000003 00000000 c7337b68 00000000 c67e4400 00001000 c7337b80 f80935e5 00000000 00000000 00000000 00000000 e1fcf000 0000000f e59be618 c70bf900 Call Trace: [<f8091f6d>] logfs_get_write_page.clone.16+0xdd/0x100 [logfs] [<f80935e5>] logfs_mod_segment_entry+0x55/0x110 [logfs] [<f809460d>] logfs_get_segment_entry+0x1d/0x20 [logfs] [<f8091060>] ? logfs_cleanup_journal+0x50/0x50 [logfs] [<f809521b>] ostore_get_erase_count+0x1b/0x40 [logfs] [<f80965b8>] logfs_open_area+0xc8/0x150 [logfs] [<c141a7ec>] ? kmemleak_alloc+0x2c/0x60 [<f809668e>] __logfs_segment_write.clone.16+0x4e/0x1b0 [logfs] [<c10dd563>] ? mempool_kmalloc+0x13/0x20 [<c10dd563>] ? mempool_kmalloc+0x13/0x20 [<f809696f>] logfs_segment_write+0x17f/0x1d0 [logfs] [<f8092e8c>] logfs_write_i0+0x11c/0x180 [logfs] [<f8092f35>] logfs_write_direct+0x45/0x90 [logfs] [<f80934cd>] __logfs_write_buf+0xbd/0xf0 [logfs] [<c102900e>] ? kmap_atomic_prot+0x4e/0xe0 [<f809424b>] logfs_write_buf+0x3b/0x60 [logfs] [<f80947a9>] __logfs_write_inode+0xa9/0x110 [logfs] [<f8094cb0>] logfs_rewrite_block+0xc0/0x110 [logfs] [<f8095300>] ? get_mapping_page+0x10/0x60 [logfs] [<f8095aa0>] ? logfs_load_object_aliases+0x2e0/0x2f0 [logfs] [<f808e57d>] logfs_gc_segment+0x2ad/0x310 [logfs] [<f808e62a>] __logfs_gc_once+0x4a/0x80 [logfs] [<f808ed43>] logfs_gc_pass+0x683/0x6a0 [logfs] [<f8097a89>] logfs_mount+0x5a9/0x680 [logfs] [<c1126b21>] mount_fs+0x21/0xd0 [<c10f6f6f>] ? __alloc_percpu+0xf/0x20 [<c113da41>] ? alloc_vfsmnt+0xb1/0x130 [<c113db4b>] vfs_kern_mount+0x4b/0xa0 [<c113e06e>] do_kern_mount+0x3e/0xe0 [<c113f60d>] do_mount+0x34d/0x670 [<c10f2749>] ? strndup_user+0x49/0x70 [<c113fcab>] sys_mount+0x6b/0xa0 [<c142d87c>] syscall_call+0x7/0xb Code: f8 e8 8b 93 39 c9 8b 45 f8 3e 0f ba 28 00 19 d2 85 d2 74 ca eb d0 0f 0b 8d 45 fc 89 44 24 04 c7 04 24 3d 9a 09 f8 e8 09 92 39 c9 <0f> 0b 8d 74 26 00 55 89 e5 3e 8d 74 26 00 8b 10 80 e6 01 74 09 EIP: [<f809132a>] logfs_lock_write_page+0x6a/0x70 [logfs] SS:ESP 0068:c7337b18 ---[ end trace 96e67d5b3aa3d6ca ]--- The patch passes locked page to __logfs_write_inode. It calls function logfs_get_wblocks() to pre-lock the page. This ensures any further attempts to lock the page are ignored (esp from get_erase_count). Acked-by: Joern Engel <joern@logfs.org> Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
2011-10-02 23:46:51 +05:30
logfs: take write mutex lock during fsync and sync LogFS uses super->s_write_mutex while writing data to disk. Taking the same mutex lock in sync and fsync code path solves the following BUG: ------------[ cut here ]------------ kernel BUG at /home/prasad/logfs/dev_bdev.c:134! Pid: 2387, comm: flush-253:16 Not tainted 3.0.0+ #4 Bochs Bochs RIP: 0010:[<ffffffffa007deed>] [<ffffffffa007deed>] bdev_writeseg+0x25d/0x270 [logfs] Call Trace: [<ffffffffa007c381>] logfs_open_area+0x91/0x150 [logfs] [<ffffffff8128dcb2>] ? find_level.clone.9+0x62/0x100 [<ffffffffa007c49c>] __logfs_segment_write.clone.20+0x5c/0x190 [logfs] [<ffffffff810ef005>] ? mempool_kmalloc+0x15/0x20 [<ffffffff810ef383>] ? mempool_alloc+0x53/0x130 [<ffffffffa007c7a4>] logfs_segment_write+0x1d4/0x230 [logfs] [<ffffffffa0078f8e>] logfs_write_i0+0x12e/0x190 [logfs] [<ffffffffa0079300>] __logfs_write_rec+0x140/0x220 [logfs] [<ffffffffa0079444>] logfs_write_rec+0x64/0xd0 [logfs] [<ffffffffa00795b6>] __logfs_write_buf+0x106/0x110 [logfs] [<ffffffffa007a13e>] logfs_write_buf+0x4e/0x80 [logfs] [<ffffffffa0073e33>] __logfs_writepage+0x23/0x80 [logfs] [<ffffffffa007410c>] logfs_writepage+0xdc/0x110 [logfs] [<ffffffff810f5ba7>] __writepage+0x17/0x40 [<ffffffff810f6208>] write_cache_pages+0x208/0x4f0 [<ffffffff810f5b90>] ? set_page_dirty+0x70/0x70 [<ffffffff810f653a>] generic_writepages+0x4a/0x70 [<ffffffff810f75d1>] do_writepages+0x21/0x40 [<ffffffff8116b9d1>] writeback_single_inode+0x101/0x250 [<ffffffff8116bdbd>] writeback_sb_inodes+0xed/0x1c0 [<ffffffff8116c5fb>] writeback_inodes_wb+0x7b/0x1e0 [<ffffffff8116cc23>] wb_writeback+0x4c3/0x530 [<ffffffff814d984d>] ? sub_preempt_count+0x9d/0xd0 [<ffffffff8116cd6b>] wb_do_writeback+0xdb/0x290 [<ffffffff814d984d>] ? sub_preempt_count+0x9d/0xd0 [<ffffffff814d6208>] ? _raw_spin_unlock_irqrestore+0x18/0x40 [<ffffffff8105aa5a>] ? del_timer+0x8a/0x120 [<ffffffff8116cfac>] bdi_writeback_thread+0x8c/0x2e0 [<ffffffff8116cf20>] ? wb_do_writeback+0x290/0x290 [<ffffffff8106d2e6>] kthread+0x96/0xa0 [<ffffffff814de514>] kernel_thread_helper+0x4/0x10 [<ffffffff8106d250>] ? kthread_worker_fn+0x190/0x190 [<ffffffff814de510>] ? gs_change+0xb/0xb RIP [<ffffffffa007deed>] bdev_writeseg+0x25d/0x270 [logfs] ---[ end trace 0211ad60a57657c4 ]--- Reviewed-by: Joern Engel <joern@logfs.org> Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
2012-01-28 11:36:06 +05:30