ffs_snapshot_read(): Use IO_ALTSEMANTICS to allow reading a snapshot vnode
beyond file system size. Needed to read the snapblklist
on mount.
Persistent snapshots work again.
Should fix PR kern/37425: fss_snapshot_mount panic during fsck.
ffs_snapshot_read(): Allow the kernel to read beyond file system size.
Persistent snapshots work again.
Should fix PR kern/37425: fss_snapshot_mount panic during fsck.
snapshot use. Adjust ffs_blkfree_common to get the fs instance passed
in, the original commit didn't account blocks in the snapshots
correctly. Assert that ffs_blkfree is used with the primary fs instance
and that ffs_checkfreefile is only used for snapshots. Move the bdwrite
from ffs_blkfree_common into the caller for symmetry. This creates a
redundant write of unmodified data for ffs_blkfree_snap if a double free
of a block happens.
Reviewed and tested by hannken@.
block in the cylinder groups of the filesystem. The other user is the
snapshot code, which wants to modify the copied cylinder groups. Use
different frontends to distinguish the cases in preparation for fine
grained locking for cylinder groups.
This changes the order of hook processing as the copy-on-write handlers
are called after the journal processing. This makes more sense as the
journal overwrite is logically part of the disk IO.
- Count frags, not blocks to get the file system size.
- Cannot use blksize() here, it depends on vnode size.
- Correctly update xfersize on short reads.
and wants to busy a page while another thread calls VOP_PUTPAGES on the same
vnode, takes pages busy and wants to start a wapbl transaction.
Reviewed by: Jason Thorpe <thorpej@netbsd.org>
helper functions to enhance readability. Adjust comments to reality
and test the main error paths.
While here, expand and remove the last FreeBSD->NetBSD conversion macros.
No functional change intended.
- Add UFS_WAPBL_BEGIN() / UFS_WAPBL_END() where needed.
- Expunge WAPBL log inodes from snapshots.
- Ffs_copyonwrite() and ffs_snapblkfree() must run inside a WAPBL transaction.
- Add ffs_gop_write() as a wrapper around genfs_gop_write() that makes sure
genfs_gop_write() gets always called inside a WAPBL transaction.
- Add VOP_PUTPAGES() flag PGO_JOURNALLOCKED to tag calls to VOP_PUTPAGES()
inside a WAPBL transaction.
Reviewed by: Simon Burge <simonb@netbsd.org>, Greg Oster <oster@netbsd.org>
PGO_JOURNALLOCKED / ffs_gop_write() part presented on tech-kern@.
snapshots. With this policy in place:
- Separate the snapshot vnode lock from the snapshot common lock.
Snapshots no longer need recursive vnode locks.
- Use a mutex (si_snaplock) to serialize creation, deletion, reading and
writing of snapshots.
- Move ffs_read() for snapshots into ffs_snapshot.c.
Reviewed by: Jason Thorpe <thorpej@netbsd.org>
While here change ffs_copyonwrite() to fail requests from pagedaemon that need
to copy-on-write.
repeatable panic in fstrans_getstate() found while searching for a
different USB bug. Also makes the code somewhat more readable.
Patch from Juergen Hannken-Illjes with a small rearrangement from me.
Approved by: hannken
an UFS2 file system. With the current cylinder group buffer busy it
calls ffs_getblk(). This runs through copy-on-write and may need the
current cylinder group buffer to allocate a new block for the snapshot.
While here write the cylinder group buffer synchronously after
cg_initediblk was changed because fsck_ffs will trust it.
Reviewed by: Jason Thorpe <thorpej@netbsd.org>
