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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:45:59 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:45:59 +0000 |
commit | 19fcec84d8d7d21e796c7624e521b60d28ee21ed (patch) | |
tree | 42d26aa27d1e3f7c0b8bd3fd14e7d7082f5008dc /src/crimson/os/seastore/root_block.h | |
parent | Initial commit. (diff) | |
download | ceph-upstream.tar.xz ceph-upstream.zip |
Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | src/crimson/os/seastore/root_block.h | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/src/crimson/os/seastore/root_block.h b/src/crimson/os/seastore/root_block.h new file mode 100644 index 000000000..4a5024caa --- /dev/null +++ b/src/crimson/os/seastore/root_block.h @@ -0,0 +1,109 @@ +// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- +// vim: ts=8 sw=2 smarttab + +#pragma once + +#include "crimson/os/seastore/cached_extent.h" + +namespace crimson::os::seastore { + +/** + * root_t + * + * Contains information required to find metadata roots. + * TODO: generalize this to permit more than one lba_manager implementation + */ +struct __attribute__((aligned(8), packed)) root_t { + depth_t lba_depth = 0; + depth_t segment_depth = 0; + paddr_t lba_root_addr; + paddr_t segment_root; + laddr_t onode_root = L_ADDR_NULL; + + void adjust_addrs_from_base(paddr_t base) { + if (lba_root_addr.is_relative()) { + lba_root_addr = base.add_record_relative(lba_root_addr); + } + } +}; + +/** + * RootBlock + * + * Holds the physical addresses of all metadata roots. + * In-memory values may be + * - absolute: reference to block which predates the current transaction + * - record_relative: reference to block updated in this transaction + * if !pending() + * + * Journal replay only considers deltas and must always discover the most + * recent value for the RootBlock. Because the contents of root_t above are + * very small, it's simplest to stash the entire root_t value into the delta + * and never actually write the RootBlock to a physical location (safe since + * nothing references the location of the RootBlock). + * + * As a result, Cache treats the root differently in a few ways including: + * - state will only ever be DIRTY or MUTATION_PENDING + * - RootBlock's never show up in the transaction fresh or dirty lists -- + * there's a special Transaction::root member for when the root needs to + * be mutated. + * + * TODO: Journal trimming will need to be aware of the most recent RootBlock + * delta location, or, even easier, just always write one out with the + * mutation which changes the journal trim bound. + */ +struct RootBlock : CachedExtent { + constexpr static segment_off_t SIZE = 4<<10; + using Ref = TCachedExtentRef<RootBlock>; + + root_t root; + + RootBlock() : CachedExtent(0) {} + + RootBlock(const RootBlock &rhs) = default; + + CachedExtentRef duplicate_for_write() final { + return CachedExtentRef(new RootBlock(*this)); + }; + + static constexpr extent_types_t TYPE = extent_types_t::ROOT; + extent_types_t get_type() const final { + return extent_types_t::ROOT; + } + + /// dumps root as delta + ceph::bufferlist get_delta() final { + ceph::bufferlist bl; + ceph::buffer::ptr bptr(sizeof(root_t)); + *reinterpret_cast<root_t*>(bptr.c_str()) = root; + bl.append(bptr); + return bl; + } + + /// overwrites root + void apply_delta_and_adjust_crc(paddr_t base, const ceph::bufferlist &_bl) final { + assert(_bl.length() == sizeof(root_t)); + ceph::bufferlist bl = _bl; + bl.rebuild(); + root = *reinterpret_cast<const root_t*>(bl.front().c_str()); + root.adjust_addrs_from_base(base); + } + + /// Patches relative addrs in memory based on record commit addr + void on_delta_write(paddr_t record_block_offset) final { + root.adjust_addrs_from_base(record_block_offset); + } + + complete_load_ertr::future<> complete_load() final { + ceph_abort_msg("Root is only written via deltas"); + } + + void on_initial_write() final { + ceph_abort_msg("Root is only written via deltas"); + } + + root_t &get_root() { return root; } +}; +using RootBlockRef = RootBlock::Ref; + +} |