Google Git
Sign in
apache / subversion / ad1c789941f3d332f041d00e0e507391063f24bd / . / subversion / libsvn_fs_fs / index.c
blob: 3d6b7040ae38d5c288b568fda6e300cce6c773c5 [file] [log] [blame]
/* index.c indexing support for FSFS support
*
* ====================================================================
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
* ====================================================================
*/
#include <assert.h>
#include "svn_io.h"
#include "svn_pools.h"
#include "svn_sorts.h"
#include "svn_private_config.h"
#include "private/svn_sorts_private.h"
#include "private/svn_subr_private.h"
#include "private/svn_temp_serializer.h"
#include "index.h"
#include "pack.h"
#include "temp_serializer.h"
#include "util.h"
#include "fs_fs.h"
#include "../libsvn_fs/fs-loader.h"
/* maximum length of a uint64 in an 7/8b encoding */
#define ENCODED_INT_LENGTH 10
/* APR is missing an APR_OFF_T_MAX. So, define one. We will use it to
* limit file offsets stored in the indexes.
*
* We assume that everything shorter than 64 bits, it is at least 32 bits.
* We also assume that the type is always signed meaning we only have an
* effective positive range of 63 or 31 bits, respectively.
*/
static
const apr_uint64_t off_t_max = (sizeof(apr_off_t) == sizeof(apr_int64_t))
? APR_INT64_MAX
: APR_INT32_MAX;
/* We store P2L proto-index entries as 6 values, 64 bits each on disk.
* See also svn_fs_fs__p2l_proto_index_add_entry().
*/
#define P2L_PROTO_INDEX_ENTRY_SIZE (6 * sizeof(apr_uint64_t))
/* We put this string in front of the L2P index header. */
#define L2P_STREAM_PREFIX "L2P-INDEX\n"
/* We put this string in front of the P2L index header. */
#define P2L_STREAM_PREFIX "P2L-INDEX\n"
/* Size of the buffer that will fit the index header prefixes. */
#define STREAM_PREFIX_LEN MAX(sizeof(L2P_STREAM_PREFIX), \
sizeof(P2L_STREAM_PREFIX))
/* Page tables in the log-to-phys index file exclusively contain entries
* of this type to describe position and size of a given page.
*/
typedef struct l2p_page_table_entry_t
{
/* global offset on the page within the index file */
apr_uint64_t offset;
/* number of mapping entries in that page */
apr_uint32_t entry_count;
/* size of the page on disk (in the index file) */
apr_uint32_t size;
} l2p_page_table_entry_t;
/* Master run-time data structure of an log-to-phys index. It contains
* the page tables of every revision covered by that index - but not the
* pages themselves.
*/
typedef struct l2p_header_t
{
/* first revision covered by this index */
svn_revnum_t first_revision;
/* number of revisions covered */
apr_size_t revision_count;
/* (max) number of entries per page */
apr_uint32_t page_size;
/* indexes into PAGE_TABLE that mark the first page of the respective
* revision. PAGE_TABLE_INDEX[REVISION_COUNT] points to the end of
* PAGE_TABLE.
*/
apr_size_t * page_table_index;
/* Page table covering all pages in the index */
l2p_page_table_entry_t * page_table;
} l2p_header_t;
/* Run-time data structure containing a single log-to-phys index page.
*/
typedef struct l2p_page_t
{
/* number of entries in the OFFSETS array */
apr_uint32_t entry_count;
/* global file offsets (item index is the array index) within the
* packed or non-packed rev file. Offset will be -1 for unused /
* invalid item index values. */
apr_uint64_t *offsets;
} l2p_page_t;
/* All of the log-to-phys proto index file consist of entries of this type.
*/
typedef struct l2p_proto_entry_t
{
/* phys offset + 1 of the data container. 0 for "new revision" entries. */
apr_uint64_t offset;
/* corresponding item index. 0 for "new revision" entries. */
apr_uint64_t item_index;
} l2p_proto_entry_t;
/* Master run-time data structure of an phys-to-log index. It contains
* an array with one offset value for each rev file cluster.
*/
typedef struct p2l_header_t
{
/* first revision covered by the index (and rev file) */
svn_revnum_t first_revision;
/* number of bytes in the rev files covered by each p2l page */
apr_uint64_t page_size;
/* number of pages / clusters in that rev file */
apr_size_t page_count;
/* number of bytes in the rev file */
apr_uint64_t file_size;
/* offsets of the pages / cluster descriptions within the index file */
apr_off_t *offsets;
} p2l_header_t;
/*
* packed stream
*
* This is a utility object that will read files containing 7b/8b encoded
* unsigned integers. It decodes them in batches to minimize overhead
* and supports random access to random file locations.
*/
/* How many numbers we will pre-fetch and buffer in a packed number stream.
*/
enum { MAX_NUMBER_PREFETCH = 64 };
/* Prefetched number entry in a packed number stream.
*/
typedef struct value_position_pair_t
{
/* prefetched number */
apr_uint64_t value;
/* number of bytes read, *including* this number, since the buffer start */
apr_size_t total_len;
} value_position_pair_t;
/* State of a prefetching packed number stream. It will read compressed
* index data efficiently and present it as a series of non-packed uint64.
*/
struct svn_fs_fs__packed_number_stream_t
{
/* underlying data file containing the packed values */
apr_file_t *file;
/* Offset within FILE at which the stream data starts
* (i.e. which offset will reported as offset 0 by packed_stream_offset). */
apr_off_t stream_start;
/* First offset within FILE after the stream data.
* Attempts to read beyond this will cause an "Unexpected End Of Stream"
* error. */
apr_off_t stream_end;
/* number of used entries in BUFFER (starting at index 0) */
apr_size_t used;
/* index of the next number to read from the BUFFER (0 .. USED).
* If CURRENT == USED, we need to read more data upon get() */
apr_size_t current;
/* offset in FILE from which the first entry in BUFFER has been read */
apr_off_t start_offset;
/* offset in FILE from which the next number has to be read */
apr_off_t next_offset;
/* read the file in chunks of this size */
apr_size_t block_size;
/* pool to be used for file ops etc. */
apr_pool_t *pool;
/* buffer for prefetched values */
value_position_pair_t buffer[MAX_NUMBER_PREFETCH];
};
/* Return an svn_error_t * object for error ERR on STREAM with the given
* MESSAGE string. The latter must have a placeholder for the index file
* name ("%s") and the current read offset (e.g. "0x%lx").
*/
static svn_error_t *
stream_error_create(svn_fs_fs__packed_number_stream_t *stream,
apr_status_t err,
const char *message)
{
const char *file_name;
apr_off_t offset;
SVN_ERR(svn_io_file_name_get(&file_name, stream->file,
stream->pool));
SVN_ERR(svn_io_file_get_offset(&offset, stream->file, stream->pool));
return svn_error_createf(err, NULL, message, file_name,
apr_psprintf(stream->pool,
"%" APR_UINT64_T_HEX_FMT,
(apr_uint64_t)offset));
}
/* Read up to MAX_NUMBER_PREFETCH numbers from the STREAM->NEXT_OFFSET in
* STREAM->FILE and buffer them.
*
* We don't want GCC and others to inline this (infrequently called)
* function into packed_stream_get() because it prevents the latter from
* being inlined itself.
*/
SVN__PREVENT_INLINE
static svn_error_t *
packed_stream_read(svn_fs_fs__packed_number_stream_t *stream)
{
unsigned char buffer[MAX_NUMBER_PREFETCH];
apr_size_t bytes_read = 0;
apr_size_t i;
value_position_pair_t *target;
apr_off_t block_start = 0;
apr_off_t block_left = 0;
apr_status_t err;
/* all buffered data will have been read starting here */
stream->start_offset = stream->next_offset;
/* packed numbers are usually not aligned to MAX_NUMBER_PREFETCH blocks,
* i.e. the last number has been incomplete (and not buffered in stream)
* and need to be re-read. Therefore, always correct the file pointer.
*/
SVN_ERR(svn_io_file_aligned_seek(stream->file, stream->block_size,
&block_start, stream->next_offset,
stream->pool));
/* prefetch at least one number but, if feasible, don't cross block
* boundaries. This shall prevent jumping back and forth between two
* blocks because the extra data was not actually request _now_.
*/
bytes_read = sizeof(buffer);
block_left = stream->block_size - (stream->next_offset - block_start);
if (block_left >= 10 && block_left < bytes_read)
bytes_read = (apr_size_t)block_left;
/* Don't read beyond the end of the file section that belongs to this
* index / stream. */
bytes_read = (apr_size_t)MIN(bytes_read,
stream->stream_end - stream->next_offset);
err = apr_file_read(stream->file, buffer, &bytes_read);
if (err && !APR_STATUS_IS_EOF(err))
return stream_error_create(stream, err,
_("Can't read index file '%s' at offset 0x%s"));
/* if the last number is incomplete, trim it from the buffer */
while (bytes_read > 0 && buffer[bytes_read-1] >= 0x80)
--bytes_read;
/* we call read() only if get() requires more data. So, there must be
* at least *one* further number. */
if SVN__PREDICT_FALSE(bytes_read == 0)
return stream_error_create(stream, err,
_("Unexpected end of index file %s at offset 0x%s"));
/* parse file buffer and expand into stream buffer */
target = stream->buffer;
for (i = 0; i < bytes_read;)
{
if (buffer[i] < 0x80)
{
/* numbers < 128 are relatively frequent and particularly easy
* to decode. Give them special treatment. */
target->value = buffer[i];
++i;
target->total_len = i;
++target;
}
else
{
apr_uint64_t value = 0;
apr_uint64_t shift = 0;
while (buffer[i] >= 0x80)
{
value += ((apr_uint64_t)buffer[i] & 0x7f) << shift;
shift += 7;
++i;
}
target->value = value + ((apr_uint64_t)buffer[i] << shift);
++i;
target->total_len = i;
++target;
/* let's catch corrupted data early. It would surely cause
* havoc further down the line. */
if SVN__PREDICT_FALSE(shift > 8 * sizeof(value))
return svn_error_createf(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Corrupt index: number too large"));
}
}
/* update stream state */
stream->used = target - stream->buffer;
stream->next_offset = stream->start_offset + i;
stream->current = 0;
return SVN_NO_ERROR;
}
/* Create and open a packed number stream reading from offsets START to
* END in FILE and return it in *STREAM. Access the file in chunks of
* BLOCK_SIZE bytes. Expect the stream to be prefixed by STREAM_PREFIX.
* Allocate *STREAM in RESULT_POOL and use SCRATCH_POOL for temporaries.
*/
static svn_error_t *
packed_stream_open(svn_fs_fs__packed_number_stream_t **stream,
apr_file_t *file,
apr_off_t start,
apr_off_t end,
const char *stream_prefix,
apr_size_t block_size,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
char buffer[STREAM_PREFIX_LEN + 1] = { 0 };
apr_size_t len = strlen(stream_prefix);
svn_fs_fs__packed_number_stream_t *result;
/* If this is violated, we forgot to adjust STREAM_PREFIX_LEN after
* changing the index header prefixes. */
SVN_ERR_ASSERT(len < sizeof(buffer));
/* Read the header prefix and compare it with the expected prefix */
SVN_ERR(svn_io_file_aligned_seek(file, block_size, NULL, start,
scratch_pool));
SVN_ERR(svn_io_file_read_full2(file, buffer, len, NULL, NULL,
scratch_pool));
if (strncmp(buffer, stream_prefix, len))
return svn_error_createf(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Index stream header prefix mismatch.\n"
" expected: %s"
" found: %s"), stream_prefix, buffer);
/* Construct the actual stream object. */
result = apr_palloc(result_pool, sizeof(*result));
result->pool = result_pool;
result->file = file;
result->stream_start = start + len;
result->stream_end = end;
result->used = 0;
result->current = 0;
result->start_offset = result->stream_start;
result->next_offset = result->stream_start;
result->block_size = block_size;
*stream = result;
return SVN_NO_ERROR;
}
/*
* The forced inline is required for performance reasons: This is a very
* hot code path (called for every item we read) but e.g. GCC would rather
* chose to inline packed_stream_read() here, preventing packed_stream_get
* from being inlined itself.
*/
SVN__FORCE_INLINE
static svn_error_t*
packed_stream_get(apr_uint64_t *value,
svn_fs_fs__packed_number_stream_t *stream)
{
if (stream->current == stream->used)
SVN_ERR(packed_stream_read(stream));
*value = stream->buffer[stream->current].value;
++stream->current;
return SVN_NO_ERROR;
}
/* Navigate STREAM to packed stream offset OFFSET. There will be no checks
* whether the given OFFSET is valid.
*/
static void
packed_stream_seek(svn_fs_fs__packed_number_stream_t *stream,
apr_off_t offset)
{
apr_off_t file_offset = offset + stream->stream_start;
if ( stream->used == 0
|| offset < stream->start_offset
|| offset >= stream->next_offset)
{
/* outside buffered data. Next get() will read() from OFFSET. */
stream->start_offset = file_offset;
stream->next_offset = file_offset;
stream->current = 0;
stream->used = 0;
}
else
{
/* Find the suitable location in the stream buffer.
* Since our buffer is small, it is efficient enough to simply scan
* it for the desired position. */
apr_size_t i;
for (i = 0; i < stream->used; ++i)
if (stream->buffer[i].total_len > file_offset - stream->start_offset)
break;
stream->current = i;
}
}
/* Return the packed stream offset of at which the next number in the stream
* can be found.
*/
static apr_off_t
packed_stream_offset(svn_fs_fs__packed_number_stream_t *stream)
{
apr_off_t file_offset
= stream->current == 0
? stream->start_offset
: stream->buffer[stream->current-1].total_len + stream->start_offset;
return file_offset - stream->stream_start;
}
/* Encode VALUE as 7/8b into P and return the number of bytes written.
* This will be used when _writing_ packed data. packed_stream_* is for
* read operations only.
*/
static apr_size_t
encode_uint(unsigned char *p, apr_uint64_t value)
{
unsigned char *start = p;
while (value >= 0x80)
{
*p = (unsigned char)((value % 0x80) + 0x80);
value /= 0x80;
++p;
}
*p = (unsigned char)(value % 0x80);
return (p - start) + 1;
}
/* Encode VALUE as 7/8b into P and return the number of bytes written.
* This maps signed ints onto unsigned ones.
*/
static apr_size_t
encode_int(unsigned char *p, apr_int64_t value)
{
return encode_uint(p, (apr_uint64_t)(value < 0 ? -1 - 2*value : 2*value));
}
/* Append VALUE to STREAM in 7/8b encoding.
*/
static svn_error_t *
stream_write_encoded(svn_stream_t *stream,
apr_uint64_t value)
{
unsigned char encoded[ENCODED_INT_LENGTH];
apr_size_t len = encode_uint(encoded, value);
return svn_error_trace(svn_stream_write(stream, (char *)encoded, &len));
}
/* Map unsigned VALUE back to signed integer.
*/
static apr_int64_t
decode_int(apr_uint64_t value)
{
return (apr_int64_t)(value % 2 ? -1 - value / 2 : value / 2);
}
/* Write VALUE to the PROTO_INDEX file, using SCRATCH_POOL for temporary
* allocations.
*
* The point of this function is to ensure an architecture-independent
* proto-index file format. All data is written as unsigned 64 bits ints
* in little endian byte order. 64 bits is the largest portable integer
* we have and unsigned values have well-defined conversions in C.
*/
static svn_error_t *
write_uint64_to_proto_index(apr_file_t *proto_index,
apr_uint64_t value,
apr_pool_t *scratch_pool)
{
apr_byte_t buffer[sizeof(value)];
int i;
apr_size_t written;
/* Split VALUE into 8 bytes using LE ordering. */
for (i = 0; i < sizeof(buffer); ++i)
{
/* Unsigned conversions are well-defined ... */
buffer[i] = (apr_byte_t)value;
value >>= CHAR_BIT;
}
/* Write it all to disk. */
SVN_ERR(svn_io_file_write_full(proto_index, buffer, sizeof(buffer),
&written, scratch_pool));
SVN_ERR_ASSERT(written == sizeof(buffer));
return SVN_NO_ERROR;
}
/* Read one unsigned 64 bit value from PROTO_INDEX file and return it in
* *VALUE_P. If EOF is NULL, error out when trying to read beyond EOF.
* Use SCRATCH_POOL for temporary allocations.
*
* This function is the inverse to write_uint64_to_proto_index (see there),
* reading the external LE byte order and convert it into host byte order.
*/
static svn_error_t *
read_uint64_from_proto_index(apr_file_t *proto_index,
apr_uint64_t *value_p,
svn_boolean_t *eof,
apr_pool_t *scratch_pool)
{
apr_byte_t buffer[sizeof(*value_p)];
apr_size_t bytes_read;
/* Read the full 8 bytes or our 64 bit value, unless we hit EOF.
* Assert that we never read partial values. */
SVN_ERR(svn_io_file_read_full2(proto_index, buffer, sizeof(buffer),
&bytes_read, eof, scratch_pool));
SVN_ERR_ASSERT((eof && *eof) || bytes_read == sizeof(buffer));
/* If we did not hit EOF, reconstruct the uint64 value and return it. */
if (!eof || !*eof)
{
int i;
apr_uint64_t value;
/* This could only overflow if CHAR_BIT had a value that is not
* a divisor of 64. */
value = 0;
for (i = sizeof(buffer) - 1; i >= 0; --i)
value = (value << CHAR_BIT) + buffer[i];
*value_p = value;
}
return SVN_NO_ERROR;
}
/* Convenience function similar to read_uint64_from_proto_index, but returns
* an uint32 value in VALUE_P. Return an error if the value does not fit.
*/
static svn_error_t *
read_uint32_from_proto_index(apr_file_t *proto_index,
apr_uint32_t *value_p,
svn_boolean_t *eof,
apr_pool_t *scratch_pool)
{
apr_uint64_t value;
SVN_ERR(read_uint64_from_proto_index(proto_index, &value, eof,
scratch_pool));
if (!eof || !*eof)
{
if (value > APR_UINT32_MAX)
return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW, NULL,
_("UINT32 0x%s too large, max = 0x%s"),
apr_psprintf(scratch_pool,
"%" APR_UINT64_T_HEX_FMT,
value),
apr_psprintf(scratch_pool,
"%" APR_UINT64_T_HEX_FMT,
(apr_uint64_t)APR_UINT32_MAX));
/* This conversion is not lossy because the value can be represented
* in the target type. */
*value_p = (apr_uint32_t)value;
}
return SVN_NO_ERROR;
}
/* Convenience function similar to read_uint64_from_proto_index, but returns
* an off_t value in VALUE_P. Return an error if the value does not fit.
*/
static svn_error_t *
read_off_t_from_proto_index(apr_file_t *proto_index,
apr_off_t *value_p,
svn_boolean_t *eof,
apr_pool_t *scratch_pool)
{
apr_uint64_t value;
SVN_ERR(read_uint64_from_proto_index(proto_index, &value, eof,
scratch_pool));
if (!eof || !*eof)
{
if (value > off_t_max)
return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW, NULL,
_("File offset 0x%s too large, max = 0x%s"),
apr_psprintf(scratch_pool,
"%" APR_UINT64_T_HEX_FMT,
value),
apr_psprintf(scratch_pool,
"%" APR_UINT64_T_HEX_FMT,
off_t_max));
/* Shortening conversion from unsigned to signed int is well-defined
* and not lossy in C because the value can be represented in the
* target type. */
*value_p = (apr_off_t)value;
}
return SVN_NO_ERROR;
}
/*
* log-to-phys index
*/
/* Append ENTRY to log-to-phys PROTO_INDEX file.
* Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
write_l2p_entry_to_proto_index(apr_file_t *proto_index,
l2p_proto_entry_t entry,
apr_pool_t *scratch_pool)
{
SVN_ERR(write_uint64_to_proto_index(proto_index, entry.offset,
scratch_pool));
SVN_ERR(write_uint64_to_proto_index(proto_index, entry.item_index,
scratch_pool));
return SVN_NO_ERROR;
}
/* Read *ENTRY from log-to-phys PROTO_INDEX file and indicate end-of-file
* in *EOF, or error out in that case if EOF is NULL. *ENTRY is in an
* undefined state if an end-of-file occurred.
* Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
read_l2p_entry_from_proto_index(apr_file_t *proto_index,
l2p_proto_entry_t *entry,
svn_boolean_t *eof,
apr_pool_t *scratch_pool)
{
SVN_ERR(read_uint64_from_proto_index(proto_index, &entry->offset, eof,
scratch_pool));
SVN_ERR(read_uint64_from_proto_index(proto_index, &entry->item_index, eof,
scratch_pool));
return SVN_NO_ERROR;
}
/* Write the log-2-phys index page description for the l2p_page_entry_t
* array ENTRIES, starting with element START up to but not including END.
* Write the resulting representation into BUFFER. Use SCRATCH_POOL for
* temporary allocations.
*/
static svn_error_t *
encode_l2p_page(apr_array_header_t *entries,
int start,
int end,
svn_spillbuf_t *buffer,
apr_pool_t *scratch_pool)
{
unsigned char encoded[ENCODED_INT_LENGTH];
int i;
const apr_uint64_t *values = (const apr_uint64_t *)entries->elts;
apr_uint64_t last_value = 0;
/* encode items */
for (i = start; i < end; ++i)
{
apr_int64_t diff = values[i] - last_value;
last_value = values[i];
SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded,
encode_int(encoded, diff), scratch_pool));
}
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__l2p_proto_index_open(apr_file_t **proto_index,
const char *file_name,
apr_pool_t *result_pool)
{
SVN_ERR(svn_io_file_open(proto_index, file_name, APR_READ | APR_WRITE
| APR_CREATE | APR_APPEND | APR_BUFFERED,
APR_OS_DEFAULT, result_pool));
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__l2p_proto_index_add_revision(apr_file_t *proto_index,
apr_pool_t *scratch_pool)
{
l2p_proto_entry_t entry;
entry.offset = 0;
entry.item_index = 0;
return svn_error_trace(write_l2p_entry_to_proto_index(proto_index, entry,
scratch_pool));
}
svn_error_t *
svn_fs_fs__l2p_proto_index_add_entry(apr_file_t *proto_index,
apr_off_t offset,
apr_uint64_t item_index,
apr_pool_t *scratch_pool)
{
l2p_proto_entry_t entry;
/* make sure the conversion to uint64 works */
SVN_ERR_ASSERT(offset >= -1);
/* we support offset '-1' as a "not used" indication */
entry.offset = (apr_uint64_t)offset + 1;
/* make sure we can use item_index as an array index when building the
* final index file */
SVN_ERR_ASSERT(item_index < UINT_MAX / 2);
entry.item_index = item_index;
return svn_error_trace(write_l2p_entry_to_proto_index(proto_index, entry,
scratch_pool));
}
svn_error_t *
svn_fs_fs__l2p_index_append(svn_checksum_t **checksum,
svn_fs_t *fs,
apr_file_t *index_file,
const char *proto_file_name,
svn_revnum_t revision,
apr_pool_t * result_pool,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
apr_file_t *proto_index = NULL;
svn_stream_t *stream;
int i;
apr_uint64_t entry;
svn_boolean_t eof = FALSE;
int last_page_count = 0; /* total page count at the start of
the current revision */
/* temporary data structures that collect the data which will be moved
to the target file in a second step */
apr_pool_t *local_pool = svn_pool_create(scratch_pool);
apr_pool_t *iterpool = svn_pool_create(local_pool);
apr_array_header_t *page_counts
= apr_array_make(local_pool, 16, sizeof(apr_uint64_t));
apr_array_header_t *page_sizes
= apr_array_make(local_pool, 16, sizeof(apr_uint64_t));
apr_array_header_t *entry_counts
= apr_array_make(local_pool, 16, sizeof(apr_uint64_t));
/* collect the item offsets and sub-item value for the current revision */
apr_array_header_t *entries
= apr_array_make(local_pool, 256, sizeof(apr_uint64_t));
/* 64k blocks, spill after 16MB */
svn_spillbuf_t *buffer
= svn_spillbuf__create(0x10000, 0x1000000, local_pool);
/* Paranoia check that makes later casting to int32 safe.
* The current implementation is limited to 2G entries per page. */
if (ffd->l2p_page_size > APR_INT32_MAX)
return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL,
_("L2P index page size %s"
" exceeds current limit of 2G entries"),
apr_psprintf(local_pool, "%" APR_UINT64_T_FMT,
ffd->l2p_page_size));
/* start at the beginning of the source file */
SVN_ERR(svn_io_file_open(&proto_index, proto_file_name,
APR_READ | APR_CREATE | APR_BUFFERED,
APR_OS_DEFAULT, scratch_pool));
/* process all entries until we fail due to EOF */
for (entry = 0; !eof; ++entry)
{
l2p_proto_entry_t proto_entry;
/* (attempt to) read the next entry from the source */
SVN_ERR(read_l2p_entry_from_proto_index(proto_index, &proto_entry,
&eof, local_pool));
/* handle new revision */
if (eof || (entry > 0 && proto_entry.offset == 0))
{
/* dump entries, grouped into pages */
int entry_count = 0;
for (i = 0; i < entries->nelts; i += entry_count)
{
/* 1 page with up to L2P_PAGE_SIZE entries.
* fsfs.conf settings validation guarantees this to fit into
* our address space. */
apr_uint64_t last_buffer_size
= (apr_uint64_t)svn_spillbuf__get_size(buffer);
svn_pool_clear(iterpool);
entry_count = ffd->l2p_page_size < entries->nelts - i
? (int)ffd->l2p_page_size
: entries->nelts - i;
SVN_ERR(encode_l2p_page(entries, i, i + entry_count,
buffer, iterpool));
APR_ARRAY_PUSH(entry_counts, apr_uint64_t) = entry_count;
APR_ARRAY_PUSH(page_sizes, apr_uint64_t)
= svn_spillbuf__get_size(buffer) - last_buffer_size;
}
apr_array_clear(entries);
/* store the number of pages in this revision */
APR_ARRAY_PUSH(page_counts, apr_uint64_t)
= page_sizes->nelts - last_page_count;
last_page_count = page_sizes->nelts;
}
else
{
int idx;
/* store the mapping in our array */
if (proto_entry.item_index > APR_INT32_MAX)
return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL,
_("Item index %s too large "
"in l2p proto index for revision %ld"),
apr_psprintf(local_pool, "%" APR_UINT64_T_FMT,
proto_entry.item_index),
revision + page_counts->nelts);
idx = (int)proto_entry.item_index;
while (idx >= entries->nelts)
APR_ARRAY_PUSH(entries, apr_uint64_t) = 0;
APR_ARRAY_IDX(entries, idx, apr_uint64_t) = proto_entry.offset;
}
}
/* close the source file */
SVN_ERR(svn_io_file_close(proto_index, local_pool));
/* Paranoia check that makes later casting to int32 safe.
* The current implementation is limited to 2G pages per index. */
if (page_counts->nelts > APR_INT32_MAX)
return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL,
_("L2P index page count %d"
" exceeds current limit of 2G pages"),
page_counts->nelts);
/* open target stream. */
stream = svn_stream_checksummed2(svn_stream_from_aprfile2(index_file, TRUE,
local_pool),
NULL, checksum, svn_checksum_md5, FALSE,
result_pool);
/* write header info */
SVN_ERR(svn_stream_puts(stream, L2P_STREAM_PREFIX));
SVN_ERR(stream_write_encoded(stream, revision));
SVN_ERR(stream_write_encoded(stream, ffd->l2p_page_size));
SVN_ERR(stream_write_encoded(stream, page_counts->nelts));
SVN_ERR(stream_write_encoded(stream, page_sizes->nelts));
/* write the revision table */
for (i = 0; i < page_counts->nelts; ++i)
{
apr_uint64_t value = APR_ARRAY_IDX(page_counts, i, apr_uint64_t);
SVN_ERR(stream_write_encoded(stream, value));
}
/* write the page table */
for (i = 0; i < page_sizes->nelts; ++i)
{
apr_uint64_t value = APR_ARRAY_IDX(page_sizes, i, apr_uint64_t);
SVN_ERR(stream_write_encoded(stream, value));
value = APR_ARRAY_IDX(entry_counts, i, apr_uint64_t);
SVN_ERR(stream_write_encoded(stream, value));
}
/* append page contents and implicitly close STREAM */
SVN_ERR(svn_stream_copy3(svn_stream__from_spillbuf(buffer, local_pool),
stream, NULL, NULL, local_pool));
svn_pool_destroy(local_pool);
return SVN_NO_ERROR;
}
/* If REV_FILE->L2P_STREAM is NULL, create a new stream for the log-to-phys
* index for REVISION in FS and return it in REV_FILE.
*/
static svn_error_t *
auto_open_l2p_index(svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
svn_revnum_t revision)
{
if (rev_file->l2p_stream == NULL)
{
fs_fs_data_t *ffd = fs->fsap_data;
SVN_ERR(svn_fs_fs__auto_read_footer(rev_file));
SVN_ERR(packed_stream_open(&rev_file->l2p_stream,
rev_file->file,
rev_file->l2p_offset,
rev_file->p2l_offset,
L2P_STREAM_PREFIX,
(apr_size_t)ffd->block_size,
rev_file->pool,
rev_file->pool));
}
return SVN_NO_ERROR;
}
/* Read the header data structure of the log-to-phys index for REVISION
* in FS and return it in *HEADER, allocated in RESULT_POOL. Use REV_FILE
* to access on-disk data. Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
get_l2p_header_body(l2p_header_t **header,
svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
svn_revnum_t revision,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
apr_uint64_t value;
apr_size_t i;
apr_size_t page, page_count;
apr_off_t offset;
l2p_header_t *result = apr_pcalloc(result_pool, sizeof(*result));
apr_size_t page_table_index;
svn_revnum_t next_rev;
pair_cache_key_t key;
key.revision = rev_file->start_revision;
key.second = rev_file->is_packed;
SVN_ERR(auto_open_l2p_index(rev_file, fs, revision));
packed_stream_seek(rev_file->l2p_stream, 0);
/* Read the table sizes. Check the data for plausibility and
* consistency with other bits. */
SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream));
result->first_revision = (svn_revnum_t)value;
if (result->first_revision != rev_file->start_revision)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Index rev / pack file revision numbers do not match"));
SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream));
result->page_size = (apr_uint32_t)value;
if (!result->page_size || (result->page_size & (result->page_size - 1)))
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("L2P index page size is not a power of two"));
SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream));
result->revision_count = (int)value;
if ( result->revision_count != 1
&& result->revision_count != (apr_uint64_t)ffd->max_files_per_dir)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Invalid number of revisions in L2P index"));
SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream));
page_count = (apr_size_t)value;
if (page_count < result->revision_count)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Fewer L2P index pages than revisions"));
if (page_count > (rev_file->p2l_offset - rev_file->l2p_offset) / 2)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("L2P index page count implausibly large"));
next_rev = result->first_revision + (svn_revnum_t)result->revision_count;
if (result->first_revision > revision || next_rev <= revision)
return svn_error_createf(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Corrupt L2P index for r%ld only covers r%ld:%ld"),
revision, result->first_revision, next_rev);
/* allocate the page tables */
result->page_table
= apr_pcalloc(result_pool, page_count * sizeof(*result->page_table));
result->page_table_index
= apr_pcalloc(result_pool, (result->revision_count + 1)
* sizeof(*result->page_table_index));
/* read per-revision page table sizes (i.e. number of pages per rev) */
page_table_index = 0;
result->page_table_index[0] = page_table_index;
for (i = 0; i < result->revision_count; ++i)
{
SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream));
if (value == 0)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Revision with no L2P index pages"));
page_table_index += (apr_size_t)value;
if (page_table_index > page_count)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("L2P page table exceeded"));
result->page_table_index[i+1] = page_table_index;
}
if (page_table_index != page_count)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Revisions do not cover the full L2P index page table"));
/* read actual page tables */
for (page = 0; page < page_count; ++page)
{
SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream));
if (value == 0)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Empty L2P index page"));
result->page_table[page].size = (apr_uint32_t)value;
SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream));
if (value > result->page_size)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Page exceeds L2P index page size"));
result->page_table[page].entry_count = (apr_uint32_t)value;
}
/* correct the page description offsets */
offset = packed_stream_offset(rev_file->l2p_stream);
for (page = 0; page < page_count; ++page)
{
result->page_table[page].offset = offset;
offset += result->page_table[page].size;
}
/* return and cache the header */
*header = result;
SVN_ERR(svn_cache__set(ffd->l2p_header_cache, &key, result, scratch_pool));
return SVN_NO_ERROR;
}
/* Data structure that describes which l2p page info shall be extracted
* from the cache and contains the fields that receive the result.
*/
typedef struct l2p_page_info_baton_t
{
/* input data: we want the page covering (REVISION,ITEM_INDEX) */
svn_revnum_t revision;
apr_uint64_t item_index;
/* out data */
/* page location and size of the page within the l2p index file */
l2p_page_table_entry_t entry;
/* page number within the pages for REVISION (not l2p index global!) */
apr_uint32_t page_no;
/* offset of ITEM_INDEX within that page */
apr_uint32_t page_offset;
/* revision identifying the l2p index file, also the first rev in that */
svn_revnum_t first_revision;
} l2p_page_info_baton_t;
/* Utility function that copies the info requested by BATON->REVISION and
* BATON->ITEM_INDEX and from HEADER and PAGE_TABLE into the output fields
* of *BATON. Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
l2p_page_info_copy(l2p_page_info_baton_t *baton,
const l2p_header_t *header,
const l2p_page_table_entry_t *page_table,
const apr_size_t *page_table_index,
apr_pool_t *scratch_pool)
{
/* revision offset within the index file */
apr_size_t rel_revision = baton->revision - header->first_revision;
if (rel_revision >= header->revision_count)
return svn_error_createf(SVN_ERR_FS_INDEX_REVISION , NULL,
_("Revision %ld not covered by item index"),
baton->revision);
/* select the relevant page */
if (baton->item_index < header->page_size)
{
/* most revs fit well into a single page */
baton->page_offset = (apr_uint32_t)baton->item_index;
baton->page_no = 0;
baton->entry = page_table[page_table_index[rel_revision]];
}
else
{
const l2p_page_table_entry_t *first_entry;
const l2p_page_table_entry_t *last_entry;
apr_uint64_t max_item_index;
/* range of pages for this rev */
first_entry = page_table + page_table_index[rel_revision];
last_entry = page_table + page_table_index[rel_revision + 1];
/* do we hit a valid index page? */
max_item_index = (apr_uint64_t)header->page_size
* (last_entry - first_entry);
if (baton->item_index >= max_item_index)
return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL,
_("Item index %s exceeds l2p limit "
"of %s for revision %ld"),
apr_psprintf(scratch_pool,
"%" APR_UINT64_T_FMT,
baton->item_index),
apr_psprintf(scratch_pool,
"%" APR_UINT64_T_FMT,
max_item_index),
baton->revision);
/* all pages are of the same size and full, except for the last one */
baton->page_offset = (apr_uint32_t)(baton->item_index % header->page_size);
baton->page_no = (apr_uint32_t)(baton->item_index / header->page_size);
baton->entry = first_entry[baton->page_no];
}
baton->first_revision = header->first_revision;
return SVN_NO_ERROR;
}
/* Implement svn_cache__partial_getter_func_t: copy the data requested in
* l2p_page_info_baton_t *BATON from l2p_header_t *DATA into the output
* fields in *BATON.
*/
static svn_error_t *
l2p_page_info_access_func(void **out,
const void *data,
apr_size_t data_len,
void *baton,
apr_pool_t *result_pool)
{
/* resolve all pointer values of in-cache data */
const l2p_header_t *header = data;
const l2p_page_table_entry_t *page_table
= svn_temp_deserializer__ptr(header,
(const void *const *)&header->page_table);
const apr_size_t *page_table_index
= svn_temp_deserializer__ptr(header,
(const void *const *)&header->page_table_index);
/* copy the info */
return l2p_page_info_copy(baton, header, page_table, page_table_index,
result_pool);
}
/* Get the page info requested in *BATON from FS and set the output fields
* in *BATON. Use REV_FILE for on-disk file access.
* Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
get_l2p_page_info(l2p_page_info_baton_t *baton,
svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
l2p_header_t *result;
svn_boolean_t is_cached = FALSE;
void *dummy = NULL;
/* try to find the info in the cache */
pair_cache_key_t key;
key.revision = rev_file->start_revision;
key.second = rev_file->is_packed;
SVN_ERR(svn_cache__get_partial((void**)&dummy, &is_cached,
ffd->l2p_header_cache, &key,
l2p_page_info_access_func, baton,
scratch_pool));
if (is_cached)
return SVN_NO_ERROR;
/* read from disk, cache and copy the result */
SVN_ERR(get_l2p_header_body(&result, rev_file, fs, baton->revision,
scratch_pool, scratch_pool));
SVN_ERR(l2p_page_info_copy(baton, result, result->page_table,
result->page_table_index, scratch_pool));
return SVN_NO_ERROR;
}
/* Data request structure used by l2p_page_table_access_func.
*/
typedef struct l2p_page_table_baton_t
{
/* revision for which to read the page table */
svn_revnum_t revision;
/* page table entries (of type l2p_page_table_entry_t).
* Must be created by caller and will be filled by callee. */
apr_array_header_t *pages;
} l2p_page_table_baton_t;
/* Implement svn_cache__partial_getter_func_t: copy the data requested in
* l2p_page_baton_t *BATON from l2p_page_t *DATA into BATON->PAGES and *OUT.
*/
static svn_error_t *
l2p_page_table_access_func(void **out,
const void *data,
apr_size_t data_len,
void *baton,
apr_pool_t *result_pool)
{
/* resolve in-cache pointers */
l2p_page_table_baton_t *table_baton = baton;
const l2p_header_t *header = (const l2p_header_t *)data;
const l2p_page_table_entry_t *page_table
= svn_temp_deserializer__ptr(header,
(const void *const *)&header->page_table);
const apr_size_t *page_table_index
= svn_temp_deserializer__ptr(header,
(const void *const *)&header->page_table_index);
/* copy the revision's page table into BATON */
apr_size_t rel_revision = table_baton->revision - header->first_revision;
if (rel_revision < header->revision_count)
{
const l2p_page_table_entry_t *entry
= page_table + page_table_index[rel_revision];
const l2p_page_table_entry_t *last_entry
= page_table + page_table_index[rel_revision + 1];
for (; entry < last_entry; ++entry)
APR_ARRAY_PUSH(table_baton->pages, l2p_page_table_entry_t)
= *entry;
}
/* set output as a courtesy to the caller */
*out = table_baton->pages;
return SVN_NO_ERROR;
}
/* Read the l2p index page table for REVISION in FS from cache and return
* it in PAGES. The later must be provided by the caller (and can be
* re-used); existing entries will be removed before writing the result.
* If the data cannot be found in the cache, the result will be empty
* (it never can be empty for a valid REVISION if the data is cached).
* Use the info from REV_FILE to determine pack / rev file properties.
* Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
get_l2p_page_table(apr_array_header_t *pages,
svn_fs_t *fs,
svn_fs_fs__revision_file_t *rev_file,
svn_revnum_t revision,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
svn_boolean_t is_cached = FALSE;
l2p_page_table_baton_t baton;
pair_cache_key_t key;
key.revision = rev_file->start_revision;
key.second = rev_file->is_packed;
apr_array_clear(pages);
baton.revision = revision;
baton.pages = pages;
SVN_ERR(svn_cache__get_partial((void**)&pages, &is_cached,
ffd->l2p_header_cache, &key,
l2p_page_table_access_func, &baton,
scratch_pool));
return SVN_NO_ERROR;
}
/* From the log-to-phys index file starting at START_REVISION in FS, read
* the mapping page identified by TABLE_ENTRY and return it in *PAGE.
* Use REV_FILE to access on-disk files.
* Use RESULT_POOL for allocations.
*/
static svn_error_t *
get_l2p_page(l2p_page_t **page,
svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
svn_revnum_t start_revision,
l2p_page_table_entry_t *table_entry,
apr_pool_t *result_pool)
{
apr_uint32_t i;
l2p_page_t *result = apr_pcalloc(result_pool, sizeof(*result));
apr_uint64_t last_value = 0;
/* open index file and select page */
SVN_ERR(auto_open_l2p_index(rev_file, fs, start_revision));
packed_stream_seek(rev_file->l2p_stream, table_entry->offset);
/* initialize the page content */
result->entry_count = table_entry->entry_count;
result->offsets = apr_pcalloc(result_pool, result->entry_count
* sizeof(*result->offsets));
/* read all page entries (offsets in rev file and container sub-items) */
for (i = 0; i < result->entry_count; ++i)
{
apr_uint64_t value = 0;
SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream));
last_value += decode_int(value);
result->offsets[i] = last_value - 1;
}
/* After reading all page entries, the read cursor must have moved by
* TABLE_ENTRY->SIZE bytes. */
if ( packed_stream_offset(rev_file->l2p_stream)
!= table_entry->offset + table_entry->size)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("L2P actual page size does not match page table value."));
*page = result;
return SVN_NO_ERROR;
}
/* Utility function. Read the l2p index pages for REVISION in FS from
* REV_FILE and put them into the cache. Skip page number EXLCUDED_PAGE_NO
* (use -1 for 'skip none') and pages outside the MIN_OFFSET, MAX_OFFSET
* range in the l2p index file. The index is being identified by
* FIRST_REVISION. PAGES is a scratch container provided by the caller.
* SCRATCH_POOL is used for temporary allocations.
*
* This function may be a no-op if the header cache lookup fails / misses.
*/
static svn_error_t *
prefetch_l2p_pages(svn_boolean_t *end,
svn_fs_t *fs,
svn_fs_fs__revision_file_t *rev_file,
svn_revnum_t first_revision,
svn_revnum_t revision,
apr_array_header_t *pages,
int exlcuded_page_no,
apr_off_t min_offset,
apr_off_t max_offset,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
int i;
apr_pool_t *iterpool;
svn_fs_fs__page_cache_key_t key = { 0 };
/* Parameter check. */
if (min_offset < 0)
min_offset = 0;
if (max_offset <= 0)
{
/* Nothing to do */
*end = TRUE;
return SVN_NO_ERROR;
}
/* get the page table for REVISION from cache */
*end = FALSE;
SVN_ERR(get_l2p_page_table(pages, fs, rev_file, revision, scratch_pool));
if (pages->nelts == 0 || rev_file->l2p_stream == NULL)
{
/* not found -> we can't continue without hitting the disk again */
*end = TRUE;
return SVN_NO_ERROR;
}
/* prefetch pages individually until all are done or we found one in
* the cache */
iterpool = svn_pool_create(scratch_pool);
assert(revision <= APR_UINT32_MAX);
key.revision = (apr_uint32_t)revision;
key.is_packed = rev_file->is_packed;
for (i = 0; i < pages->nelts && !*end; ++i)
{
svn_boolean_t is_cached;
l2p_page_table_entry_t *entry
= &APR_ARRAY_IDX(pages, i, l2p_page_table_entry_t);
svn_pool_clear(iterpool);
if (i == exlcuded_page_no)
continue;
/* skip pages outside the specified index file range */
if ( entry->offset < (apr_uint64_t)min_offset
|| entry->offset + entry->size > (apr_uint64_t)max_offset)
{
*end = TRUE;
continue;
}
/* page already in cache? */
key.page = i;
SVN_ERR(svn_cache__has_key(&is_cached, ffd->l2p_page_cache,
&key, iterpool));
if (!is_cached)
{
/* no in cache -> read from stream (data already buffered in APR)
* and cache the result */
l2p_page_t *page = NULL;
SVN_ERR(get_l2p_page(&page, rev_file, fs, first_revision, entry,
iterpool));
SVN_ERR(svn_cache__set(ffd->l2p_page_cache, &key, page,
iterpool));
}
}
svn_pool_destroy(iterpool);
return SVN_NO_ERROR;
}
/* Request data structure for l2p_entry_access_func.
*/
typedef struct l2p_entry_baton_t
{
/* in data */
/* revision. Used for error messages only */
svn_revnum_t revision;
/* item index to look up. Used for error messages only */
apr_uint64_t item_index;
/* offset within the cached page */
apr_uint32_t page_offset;
/* out data */
/* absolute item or container offset in rev / pack file */
apr_uint64_t offset;
} l2p_entry_baton_t;
/* Return the rev / pack file offset of the item at BATON->PAGE_OFFSET in
* OFFSETS of PAGE and write it to *OFFSET.
*/
static svn_error_t *
l2p_page_get_entry(l2p_entry_baton_t *baton,
const l2p_page_t *page,
const apr_uint64_t *offsets,
apr_pool_t *scratch_pool)
{
/* overflow check */
if (page->entry_count <= baton->page_offset)
return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL,
_("Item index %s"
" too large in revision %ld"),
apr_psprintf(scratch_pool, "%" APR_UINT64_T_FMT,
baton->item_index),
baton->revision);
/* return the result */
baton->offset = offsets[baton->page_offset];
return SVN_NO_ERROR;
}
/* Implement svn_cache__partial_getter_func_t: copy the data requested in
* l2p_entry_baton_t *BATON from l2p_page_t *DATA into BATON->OFFSET.
* *OUT remains unchanged.
*/
static svn_error_t *
l2p_entry_access_func(void **out,
const void *data,
apr_size_t data_len,
void *baton,
apr_pool_t *result_pool)
{
/* resolve all in-cache pointers */
const l2p_page_t *page = data;
const apr_uint64_t *offsets
= svn_temp_deserializer__ptr(page, (const void *const *)&page->offsets);
/* return the requested data */
return l2p_page_get_entry(baton, page, offsets, result_pool);
}
/* Using the log-to-phys indexes in FS, find the absolute offset in the
* rev file for (REVISION, ITEM_INDEX) and return it in *OFFSET.
* Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
l2p_index_lookup(apr_off_t *offset,
svn_fs_t *fs,
svn_fs_fs__revision_file_t *rev_file,
svn_revnum_t revision,
apr_uint64_t item_index,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
l2p_page_info_baton_t info_baton;
l2p_entry_baton_t page_baton;
l2p_page_t *page = NULL;
svn_fs_fs__page_cache_key_t key = { 0 };
svn_boolean_t is_cached = FALSE;
void *dummy = NULL;
/* read index master data structure and extract the info required to
* access the l2p index page for (REVISION,ITEM_INDEX)*/
info_baton.revision = revision;
info_baton.item_index = item_index;
SVN_ERR(get_l2p_page_info(&info_baton, rev_file, fs, scratch_pool));
/* try to find the page in the cache and get the OFFSET from it */
page_baton.revision = revision;
page_baton.item_index = item_index;
page_baton.page_offset = info_baton.page_offset;
assert(revision <= APR_UINT32_MAX);
key.revision = (apr_uint32_t)revision;
key.is_packed = svn_fs_fs__is_packed_rev(fs, revision);
key.page = info_baton.page_no;
SVN_ERR(svn_cache__get_partial(&dummy, &is_cached,
ffd->l2p_page_cache, &key,
l2p_entry_access_func, &page_baton,
scratch_pool));
if (!is_cached)
{
/* we need to read the info from disk (might already be in the
* APR file buffer, though) */
apr_array_header_t *pages;
svn_revnum_t prefetch_revision;
svn_revnum_t last_revision
= info_baton.first_revision
+ (key.is_packed ? ffd->max_files_per_dir : 1);
svn_boolean_t end;
apr_off_t max_offset
= APR_ALIGN(info_baton.entry.offset + info_baton.entry.size,
ffd->block_size);
apr_off_t min_offset = max_offset - ffd->block_size;
/* read the relevant page */
SVN_ERR(get_l2p_page(&page, rev_file, fs, info_baton.first_revision,
&info_baton.entry, scratch_pool));
/* cache the page and extract the result we need */
SVN_ERR(svn_cache__set(ffd->l2p_page_cache, &key, page, scratch_pool));
SVN_ERR(l2p_page_get_entry(&page_baton, page, page->offsets,
scratch_pool));
if (ffd->use_block_read)
{
apr_pool_t *iterpool = svn_pool_create(scratch_pool);
/* prefetch pages from following and preceding revisions */
pages = apr_array_make(scratch_pool, 16,
sizeof(l2p_page_table_entry_t));
end = FALSE;
for (prefetch_revision = revision;
prefetch_revision < last_revision && !end;
++prefetch_revision)
{
int excluded_page_no = prefetch_revision == revision
? info_baton.page_no
: -1;
svn_pool_clear(iterpool);
SVN_ERR(prefetch_l2p_pages(&end, fs, rev_file,
info_baton.first_revision,
prefetch_revision, pages,
excluded_page_no, min_offset,
max_offset, iterpool));
}
end = FALSE;
for (prefetch_revision = revision-1;
prefetch_revision >= info_baton.first_revision && !end;
--prefetch_revision)
{
svn_pool_clear(iterpool);
SVN_ERR(prefetch_l2p_pages(&end, fs, rev_file,
info_baton.first_revision,
prefetch_revision, pages, -1,
min_offset, max_offset, iterpool));
}
svn_pool_destroy(iterpool);
}
}
*offset = page_baton.offset;
return SVN_NO_ERROR;
}
/* Using the log-to-phys proto index in transaction TXN_ID in FS, find the
* absolute offset in the proto rev file for the given ITEM_INDEX and return
* it in *OFFSET. Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
l2p_proto_index_lookup(apr_off_t *offset,
svn_fs_t *fs,
const svn_fs_fs__id_part_t *txn_id,
apr_uint64_t item_index,
apr_pool_t *scratch_pool)
{
svn_boolean_t eof = FALSE;
apr_file_t *file = NULL;
SVN_ERR(svn_io_file_open(&file,
svn_fs_fs__path_l2p_proto_index(fs, txn_id,
scratch_pool),
APR_READ | APR_BUFFERED, APR_OS_DEFAULT,
scratch_pool));
/* process all entries until we fail due to EOF */
*offset = -1;
while (!eof)
{
l2p_proto_entry_t entry;
/* (attempt to) read the next entry from the source */
SVN_ERR(read_l2p_entry_from_proto_index(file, &entry, &eof,
scratch_pool));
/* handle new revision */
if (!eof && entry.item_index == item_index)
{
*offset = (apr_off_t)entry.offset - 1;
break;
}
}
SVN_ERR(svn_io_file_close(file, scratch_pool));
return SVN_NO_ERROR;
}
/* Read the log-to-phys header info of the index covering REVISION from FS
* and return it in *HEADER. REV_FILE provides the pack / rev status.
* Allocate *HEADER in RESULT_POOL, use SCRATCH_POOL for temporary
* allocations.
*/
static svn_error_t *
get_l2p_header(l2p_header_t **header,
svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
svn_revnum_t revision,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
svn_boolean_t is_cached = FALSE;
/* first, try cache lookop */
pair_cache_key_t key;
key.revision = rev_file->start_revision;
key.second = rev_file->is_packed;
SVN_ERR(svn_cache__get((void**)header, &is_cached, ffd->l2p_header_cache,
&key, result_pool));
if (is_cached)
return SVN_NO_ERROR;
/* read from disk and cache the result */
SVN_ERR(get_l2p_header_body(header, rev_file, fs, revision, result_pool,
scratch_pool));
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__l2p_get_max_ids(apr_array_header_t **max_ids,
svn_fs_t *fs,
svn_revnum_t start_rev,
apr_size_t count,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
l2p_header_t *header = NULL;
svn_revnum_t revision;
svn_revnum_t last_rev = (svn_revnum_t)(start_rev + count);
svn_fs_fs__revision_file_t *rev_file;
apr_pool_t *header_pool = svn_pool_create(scratch_pool);
/* read index master data structure for the index covering START_REV */
SVN_ERR(svn_fs_fs__open_pack_or_rev_file(&rev_file, fs, start_rev,
header_pool, header_pool));
SVN_ERR(get_l2p_header(&header, rev_file, fs, start_rev, header_pool,
header_pool));
SVN_ERR(svn_fs_fs__close_revision_file(rev_file));
/* Determine the length of the item index list for each rev.
* Read new index headers as required. */
*max_ids = apr_array_make(result_pool, (int)count, sizeof(apr_uint64_t));
for (revision = start_rev; revision < last_rev; ++revision)
{
apr_uint64_t full_page_count;
apr_uint64_t item_count;
apr_size_t first_page_index, last_page_index;
if (revision - header->first_revision >= header->revision_count)
{
/* need to read the next index. Clear up memory used for the
* previous one. Note that intermittent pack runs do not change
* the number of items in a revision, i.e. there is no consistency
* issue here. */
svn_pool_clear(header_pool);
SVN_ERR(svn_fs_fs__open_pack_or_rev_file(&rev_file, fs, revision,
header_pool, header_pool));
SVN_ERR(get_l2p_header(&header, rev_file, fs, revision,
header_pool, header_pool));
SVN_ERR(svn_fs_fs__close_revision_file(rev_file));
}
/* in a revision with N index pages, the first N-1 index pages are
* "full", i.e. contain HEADER->PAGE_SIZE entries */
first_page_index
= header->page_table_index[revision - header->first_revision];
last_page_index
= header->page_table_index[revision - header->first_revision + 1];
full_page_count = last_page_index - first_page_index - 1;
item_count = full_page_count * header->page_size
+ header->page_table[last_page_index - 1].entry_count;
APR_ARRAY_PUSH(*max_ids, apr_uint64_t) = item_count;
}
svn_pool_destroy(header_pool);
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__item_offset(apr_off_t *absolute_position,
svn_fs_t *fs,
svn_fs_fs__revision_file_t *rev_file,
svn_revnum_t revision,
const svn_fs_fs__id_part_t *txn_id,
apr_uint64_t item_index,
apr_pool_t *scratch_pool)
{
svn_error_t *err = SVN_NO_ERROR;
if (txn_id)
{
if (svn_fs_fs__use_log_addressing(fs))
{
/* the txn is going to produce a rev with logical addressing.
So, we need to get our info from the (proto) index file. */
SVN_ERR(l2p_proto_index_lookup(absolute_position, fs, txn_id,
item_index, scratch_pool));
}
else
{
/* for data in txns, item_index *is* the offset */
*absolute_position = item_index;
}
}
else if (svn_fs_fs__use_log_addressing(fs))
{
/* ordinary index lookup */
SVN_ERR(l2p_index_lookup(absolute_position, fs, rev_file, revision,
item_index, scratch_pool));
}
else if (rev_file->is_packed)
{
/* pack file with physical addressing */
apr_off_t rev_offset;
SVN_ERR(svn_fs_fs__get_packed_offset(&rev_offset, fs, revision,
scratch_pool));
*absolute_position = rev_offset + item_index;
}
else
{
/* for non-packed revs with physical addressing,
item_index *is* the offset */
*absolute_position = item_index;
}
return svn_error_trace(err);
}
/*
* phys-to-log index
*/
svn_error_t *
svn_fs_fs__p2l_proto_index_open(apr_file_t **proto_index,
const char *file_name,
apr_pool_t *result_pool)
{
SVN_ERR(svn_io_file_open(proto_index, file_name, APR_READ | APR_WRITE
| APR_CREATE | APR_APPEND | APR_BUFFERED,
APR_OS_DEFAULT, result_pool));
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__p2l_proto_index_add_entry(apr_file_t *proto_index,
const svn_fs_fs__p2l_entry_t *entry,
apr_pool_t *scratch_pool)
{
apr_uint64_t revision;
/* Make sure all signed elements of ENTRY have non-negative values.
*
* For file offsets and sizes, this is a given as we use them to describe
* absolute positions and sizes. For revisions, SVN_INVALID_REVNUM is
* valid, hence we have to shift it by 1.
*/
SVN_ERR_ASSERT(entry->offset >= 0);
SVN_ERR_ASSERT(entry->size >= 0);
SVN_ERR_ASSERT( entry->item.revision >= 0
|| entry->item.revision == SVN_INVALID_REVNUM);
revision = entry->item.revision == SVN_INVALID_REVNUM
? 0
: ((apr_uint64_t)entry->item.revision + 1);
/* Now, all values will nicely convert to uint64. */
/* Make sure to keep P2L_PROTO_INDEX_ENTRY_SIZE consistent with this: */
SVN_ERR(write_uint64_to_proto_index(proto_index, entry->offset,
scratch_pool));
SVN_ERR(write_uint64_to_proto_index(proto_index, entry->size,
scratch_pool));
SVN_ERR(write_uint64_to_proto_index(proto_index, entry->type,
scratch_pool));
SVN_ERR(write_uint64_to_proto_index(proto_index, entry->fnv1_checksum,
scratch_pool));
SVN_ERR(write_uint64_to_proto_index(proto_index, revision,
scratch_pool));
SVN_ERR(write_uint64_to_proto_index(proto_index, entry->item.number,
scratch_pool));
return SVN_NO_ERROR;
}
/* Read *ENTRY from log-to-phys PROTO_INDEX file and indicate end-of-file
* in *EOF, or error out in that case if EOF is NULL. *ENTRY is in an
* undefined state if an end-of-file occurred.
* Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
read_p2l_entry_from_proto_index(apr_file_t *proto_index,
svn_fs_fs__p2l_entry_t *entry,
svn_boolean_t *eof,
apr_pool_t *scratch_pool)
{
apr_uint64_t revision;
SVN_ERR(read_off_t_from_proto_index(proto_index, &entry->offset,
eof, scratch_pool));
SVN_ERR(read_off_t_from_proto_index(proto_index, &entry->size,
eof, scratch_pool));
SVN_ERR(read_uint32_from_proto_index(proto_index, &entry->type,
eof, scratch_pool));
SVN_ERR(read_uint32_from_proto_index(proto_index, &entry->fnv1_checksum,
eof, scratch_pool));
SVN_ERR(read_uint64_from_proto_index(proto_index, &revision,
eof, scratch_pool));
SVN_ERR(read_uint64_from_proto_index(proto_index, &entry->item.number,
eof, scratch_pool));
/* Do the inverse REVSION number conversion (see
* svn_fs_fs__p2l_proto_index_add_entry), if we actually read a complete
* record.
*/
if (!eof || !*eof)
{
/* Be careful with the arithmetics here (overflows and wrap-around): */
if (revision > 0 && revision - 1 > LONG_MAX)
return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW, NULL,
_("Revision 0x%s too large, max = 0x%s"),
apr_psprintf(scratch_pool,
"%" APR_UINT64_T_HEX_FMT,
revision),
apr_psprintf(scratch_pool,
"%" APR_UINT64_T_HEX_FMT,
(apr_uint64_t)LONG_MAX));
/* Shortening conversion from unsigned to signed int is well-defined
* and not lossy in C because the value can be represented in the
* target type. Also, cast to 'long' instead of 'svn_revnum_t' here
* to provoke a compiler warning if those types should differ and we
* would need to change the overflow checking logic.
*/
entry->item.revision = revision == 0
? SVN_INVALID_REVNUM
: (long)(revision - 1);
}
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__p2l_proto_index_next_offset(apr_off_t *next_offset,
apr_file_t *proto_index,
apr_pool_t *scratch_pool)
{
apr_off_t offset = 0;
/* Empty index file? */
SVN_ERR(svn_io_file_seek(proto_index, APR_END, &offset, scratch_pool));
if (offset == 0)
{
*next_offset = 0;
}
else
{
/* At least one entry. Read last entry. */
svn_fs_fs__p2l_entry_t entry;
offset -= P2L_PROTO_INDEX_ENTRY_SIZE;
SVN_ERR(svn_io_file_seek(proto_index, APR_SET, &offset, scratch_pool));
SVN_ERR(read_p2l_entry_from_proto_index(proto_index, &entry,
NULL, scratch_pool));
/* Return next offset. */
*next_offset = entry.offset + entry.size;
}
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__p2l_index_append(svn_checksum_t **checksum,
svn_fs_t *fs,
apr_file_t *index_file,
const char *proto_file_name,
svn_revnum_t revision,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
apr_uint64_t page_size = ffd->p2l_page_size;
apr_file_t *proto_index = NULL;
svn_stream_t *stream;
int i;
svn_boolean_t eof = FALSE;
unsigned char encoded[ENCODED_INT_LENGTH];
svn_revnum_t last_revision = revision;
apr_uint64_t last_compound = 0;
apr_uint64_t last_entry_end = 0;
apr_uint64_t last_page_end = 0;
apr_uint64_t last_buffer_size = 0; /* byte offset in the spill buffer at
the begin of the current revision */
apr_uint64_t file_size = 0;
/* temporary data structures that collect the data which will be moved
to the target file in a second step */
apr_pool_t *local_pool = svn_pool_create(scratch_pool);
apr_array_header_t *table_sizes
= apr_array_make(local_pool, 16, sizeof(apr_uint64_t));
/* 64k blocks, spill after 16MB */
svn_spillbuf_t *buffer
= svn_spillbuf__create(0x10000, 0x1000000, local_pool);
/* for loop temps ... */
apr_pool_t *iterpool = svn_pool_create(scratch_pool);
/* start at the beginning of the source file */
SVN_ERR(svn_io_file_open(&proto_index, proto_file_name,
APR_READ | APR_CREATE | APR_BUFFERED,
APR_OS_DEFAULT, scratch_pool));
/* process all entries until we fail due to EOF */
while (!eof)
{
svn_fs_fs__p2l_entry_t entry;
apr_uint64_t entry_end;
svn_boolean_t new_page = svn_spillbuf__get_size(buffer) == 0;
apr_uint64_t compound;
apr_int64_t rev_diff, compound_diff;
svn_pool_clear(iterpool);
/* (attempt to) read the next entry from the source */
SVN_ERR(read_p2l_entry_from_proto_index(proto_index, &entry,
&eof, iterpool));
/* "unused" (and usually non-existent) section to cover the offsets
at the end the of the last page. */
if (eof)
{
file_size = last_entry_end;
entry.offset = last_entry_end;
entry.size = APR_ALIGN(entry.offset, page_size) - entry.offset;
entry.type = SVN_FS_FS__ITEM_TYPE_UNUSED;
entry.fnv1_checksum = 0;
entry.item.revision = last_revision;
entry.item.number = 0;
}
else
{
/* fix-up items created when the txn's target rev was unknown */
if (entry.item.revision == SVN_INVALID_REVNUM)
entry.item.revision = revision;
}
/* end pages if entry is extending beyond their boundaries */
entry_end = entry.offset + entry.size;
while (entry_end - last_page_end > page_size)
{
apr_uint64_t buffer_size = svn_spillbuf__get_size(buffer);
APR_ARRAY_PUSH(table_sizes, apr_uint64_t)
= buffer_size - last_buffer_size;
last_buffer_size = buffer_size;
last_page_end += page_size;
new_page = TRUE;
}
/* this entry starts a new table -> store its offset
(all following entries in the same table will store sizes only) */
if (new_page)
{
SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded,
encode_uint(encoded, entry.offset),
iterpool));
last_revision = revision;
last_compound = 0;
}
/* write simple item entry */
SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded,
encode_uint(encoded, entry.size),
iterpool));
rev_diff = entry.item.revision - last_revision;
last_revision = entry.item.revision;
compound = entry.item.number * 8 + entry.type;
compound_diff = compound - last_compound;
last_compound = compound;
SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded,
encode_int(encoded, compound_diff),
iterpool));
SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded,
encode_int(encoded, rev_diff),
iterpool));
SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded,
encode_uint(encoded, entry.fnv1_checksum),
iterpool));
last_entry_end = entry_end;
}
/* close the source file */
SVN_ERR(svn_io_file_close(proto_index, local_pool));
/* store length of last table */
APR_ARRAY_PUSH(table_sizes, apr_uint64_t)
= svn_spillbuf__get_size(buffer) - last_buffer_size;
/* Open target stream. */
stream = svn_stream_checksummed2(svn_stream_from_aprfile2(index_file, TRUE,
local_pool),
NULL, checksum, svn_checksum_md5, FALSE,
result_pool);
/* write the start revision, file size and page size */
SVN_ERR(svn_stream_puts(stream, P2L_STREAM_PREFIX));
SVN_ERR(stream_write_encoded(stream, revision));
SVN_ERR(stream_write_encoded(stream, file_size));
SVN_ERR(stream_write_encoded(stream, page_size));
/* write the page table (actually, the sizes of each page description) */
SVN_ERR(stream_write_encoded(stream, table_sizes->nelts));
for (i = 0; i < table_sizes->nelts; ++i)
{
apr_uint64_t value = APR_ARRAY_IDX(table_sizes, i, apr_uint64_t);
SVN_ERR(stream_write_encoded(stream, value));
}
/* append page contents and implicitly close STREAM */
SVN_ERR(svn_stream_copy3(svn_stream__from_spillbuf(buffer, local_pool),
stream, NULL, NULL, local_pool));
svn_pool_destroy(iterpool);
svn_pool_destroy(local_pool);
return SVN_NO_ERROR;
}
/* If REV_FILE->P2L_STREAM is NULL, create a new stream for the phys-to-log
* index for REVISION in FS using the rev / pack file provided by REV_FILE.
*/
static svn_error_t *
auto_open_p2l_index(svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
svn_revnum_t revision)
{
if (rev_file->p2l_stream == NULL)
{
fs_fs_data_t *ffd = fs->fsap_data;
SVN_ERR(svn_fs_fs__auto_read_footer(rev_file));
SVN_ERR(packed_stream_open(&rev_file->p2l_stream,
rev_file->file,
rev_file->p2l_offset,
rev_file->footer_offset,
P2L_STREAM_PREFIX,
(apr_size_t)ffd->block_size,
rev_file->pool,
rev_file->pool));
}
return SVN_NO_ERROR;
}
/* Read the header data structure of the phys-to-log index for REVISION in
* FS and return it in *HEADER, allocated in RESULT_POOL. Use REV_FILE to
* access on-disk data. Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
get_p2l_header(p2l_header_t **header,
svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
svn_revnum_t revision,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
apr_uint64_t value;
apr_size_t i;
apr_off_t offset;
p2l_header_t *result;
svn_boolean_t is_cached = FALSE;
/* look for the header data in our cache */
pair_cache_key_t key;
key.revision = rev_file->start_revision;
key.second = rev_file->is_packed;
SVN_ERR(svn_cache__get((void**)header, &is_cached, ffd->p2l_header_cache,
&key, result_pool));
if (is_cached)
return SVN_NO_ERROR;
/* not found -> must read it from disk.
* Open index file or position read pointer to the begin of the file */
if (rev_file->p2l_stream == NULL)
SVN_ERR(auto_open_p2l_index(rev_file, fs, rev_file->start_revision));
else
packed_stream_seek(rev_file->p2l_stream, 0);
/* allocate result data structure */
result = apr_pcalloc(result_pool, sizeof(*result));
/* Read table sizes, check them for plausibility and allocate page array. */
SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream));
result->first_revision = (svn_revnum_t)value;
if (result->first_revision != rev_file->start_revision)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Index rev / pack file revision numbers do not match"));
SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream));
result->file_size = value;
if (result->file_size != (apr_uint64_t)rev_file->l2p_offset)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Index offset and rev / pack file size do not match"));
SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream));
result->page_size = value;
if (!result->page_size || (result->page_size & (result->page_size - 1)))
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("P2L index page size is not a power of two"));
SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream));
result->page_count = (apr_size_t)value;
if (result->page_count != (result->file_size - 1) / result->page_size + 1)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("P2L page count does not match rev / pack file size"));
result->offsets
= apr_pcalloc(result_pool, (result->page_count + 1) * sizeof(*result->offsets));
/* read page sizes and derive page description offsets from them */
result->offsets[0] = 0;
for (i = 0; i < result->page_count; ++i)
{
SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream));
result->offsets[i+1] = result->offsets[i] + (apr_off_t)value;
}
/* correct the offset values */
offset = packed_stream_offset(rev_file->p2l_stream);
for (i = 0; i <= result->page_count; ++i)
result->offsets[i] += offset;
/* cache the header data */
SVN_ERR(svn_cache__set(ffd->p2l_header_cache, &key, result, scratch_pool));
/* return the result */
*header = result;
return SVN_NO_ERROR;
}
/* Data structure that describes which p2l page info shall be extracted
* from the cache and contains the fields that receive the result.
*/
typedef struct p2l_page_info_baton_t
{
/* input variables */
/* revision identifying the index file */
svn_revnum_t revision;
/* offset within the page in rev / pack file */
apr_off_t offset;
/* output variables */
/* page containing OFFSET */
apr_size_t page_no;
/* first revision in this p2l index */
svn_revnum_t first_revision;
/* offset within the p2l index file describing this page */
apr_off_t start_offset;
/* offset within the p2l index file describing the following page */
apr_off_t next_offset;
/* PAGE_NO * PAGE_SIZE (if <= OFFSET) */
apr_off_t page_start;
/* total number of pages indexed */
apr_size_t page_count;
/* size of each page in pack / rev file */
apr_uint64_t page_size;
} p2l_page_info_baton_t;
/* From HEADER and the list of all OFFSETS, fill BATON with the page info
* requested by BATON->OFFSET.
*/
static void
p2l_page_info_copy(p2l_page_info_baton_t *baton,
const p2l_header_t *header,
const apr_off_t *offsets)
{
/* if the requested offset is out of bounds, return info for
* a zero-sized empty page right behind the last page.
*/
if (baton->offset / header->page_size < header->page_count)
{
/* This cast is safe because the value is < header->page_count. */
baton->page_no = (apr_size_t)(baton->offset / header->page_size);
baton->start_offset = offsets[baton->page_no];
baton->next_offset = offsets[baton->page_no + 1];
baton->page_size = header->page_size;
}
else
{
/* Beyond the last page. */
baton->page_no = header->page_count;
baton->start_offset = offsets[baton->page_no];
baton->next_offset = offsets[baton->page_no];
baton->page_size = 0;
}
baton->first_revision = header->first_revision;
baton->page_start = (apr_off_t)(header->page_size * baton->page_no);
baton->page_count = header->page_count;
}
/* Implement svn_cache__partial_getter_func_t: extract the p2l page info
* requested by BATON and return it in BATON.
*/
static svn_error_t *
p2l_page_info_func(void **out,
const void *data,
apr_size_t data_len,
void *baton,
apr_pool_t *result_pool)
{
/* all the pointers to cached data we need */
const p2l_header_t *header = data;
const apr_off_t *offsets
= svn_temp_deserializer__ptr(header,
(const void *const *)&header->offsets);
/* copy data from cache to BATON */
p2l_page_info_copy(baton, header, offsets);
return SVN_NO_ERROR;
}
/* Read the header data structure of the phys-to-log index for revision
* BATON->REVISION in FS. Return in *BATON all info relevant to read the
* index page for the rev / pack file offset BATON->OFFSET. Use REV_FILE
* to access on-disk data. Use SCRATCH_POOL for temporary allocations.
*/
static svn_error_t *
get_p2l_page_info(p2l_page_info_baton_t *baton,
svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
p2l_header_t *header;
svn_boolean_t is_cached = FALSE;
void *dummy = NULL;
/* look for the header data in our cache */
pair_cache_key_t key;
key.revision = rev_file->start_revision;
key.second = rev_file->is_packed;
SVN_ERR(svn_cache__get_partial(&dummy, &is_cached, ffd->p2l_header_cache,
&key, p2l_page_info_func, baton,
scratch_pool));
if (is_cached)
return SVN_NO_ERROR;
SVN_ERR(get_p2l_header(&header, rev_file, fs, baton->revision,
scratch_pool, scratch_pool));
/* copy the requested info into *BATON */
p2l_page_info_copy(baton, header, header->offsets);
return SVN_NO_ERROR;
}
/* Read a mapping entry from the phys-to-log index STREAM and append it to
* RESULT. *ITEM_INDEX contains the phys offset for the entry and will
* be moved forward by the size of entry.
*/
static svn_error_t *
read_entry(svn_fs_fs__packed_number_stream_t *stream,
apr_off_t *item_offset,
svn_revnum_t *last_revision,
apr_uint64_t *last_compound,
apr_array_header_t *result)
{
apr_uint64_t value;
svn_fs_fs__p2l_entry_t entry;
entry.offset = *item_offset;
SVN_ERR(packed_stream_get(&value, stream));
entry.size = (apr_off_t)value;
SVN_ERR(packed_stream_get(&value, stream));
*last_compound += decode_int(value);
entry.type = *last_compound & 7;
entry.item.number = *last_compound / 8;
/* Verify item type. */
if (entry.type > SVN_FS_FS__ITEM_TYPE_CHANGES)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Invalid item type in P2L index"));
if ( entry.type == SVN_FS_FS__ITEM_TYPE_CHANGES
&& entry.item.number != SVN_FS_FS__ITEM_INDEX_CHANGES)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Changed path list must have item number 1"));
SVN_ERR(packed_stream_get(&value, stream));
*last_revision += (svn_revnum_t)decode_int(value);
entry.item.revision = *last_revision;
SVN_ERR(packed_stream_get(&value, stream));
entry.fnv1_checksum = (apr_uint32_t)value;
/* Truncating the checksum to 32 bits may have hidden random data in the
* unused extra bits of the on-disk representation (7/8 bit representation
* uses 5 bytes on disk for the 32 bit value, leaving 3 bits unused). */
if (value > APR_UINT32_MAX)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Invalid FNV1 checksum in P2L index"));
/* Some of the index data for empty rev / pack file sections will not be
* used during normal operation. Thus, we have strict rules for the
* contents of those unused fields. */
if (entry.type == SVN_FS_FS__ITEM_TYPE_UNUSED)
if ( entry.item.number != SVN_FS_FS__ITEM_INDEX_UNUSED
|| entry.fnv1_checksum != 0)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("Empty regions must have item number 0 and checksum 0"));
/* Corrupted SIZE values might cause arithmetic overflow.
* The same can happen if you copy a repository from a system with 63 bit
* file lengths to one with 31 bit file lengths. */
if ((apr_uint64_t)entry.offset + (apr_uint64_t)entry.size > off_t_max)
return svn_error_create(SVN_ERR_FS_INDEX_OVERFLOW , NULL,
_("P2L index entry size overflow."));
APR_ARRAY_PUSH(result, svn_fs_fs__p2l_entry_t) = entry;
*item_offset += entry.size;
return SVN_NO_ERROR;
}
/* Read the phys-to-log mappings for the cluster beginning at rev file
* offset PAGE_START from the index for START_REVISION in FS. The data
* can be found in the index page beginning at START_OFFSET with the next
* page beginning at NEXT_OFFSET. PAGE_SIZE is the L2P index page size.
* Return the relevant index entries in *ENTRIES. Use REV_FILE to access
* on-disk data. Allocate *ENTRIES in RESULT_POOL.
*/
static svn_error_t *
get_p2l_page(apr_array_header_t **entries,
svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
svn_revnum_t start_revision,
apr_off_t start_offset,
apr_off_t next_offset,
apr_off_t page_start,
apr_uint64_t page_size,
apr_pool_t *result_pool)
{
apr_uint64_t value;
apr_array_header_t *result
= apr_array_make(result_pool, 16, sizeof(svn_fs_fs__p2l_entry_t));
apr_off_t item_offset;
apr_off_t offset;
svn_revnum_t last_revision;
apr_uint64_t last_compound;
/* open index and navigate to page start */
SVN_ERR(auto_open_p2l_index(rev_file, fs, start_revision));
packed_stream_seek(rev_file->p2l_stream, start_offset);
/* read rev file offset of the first page entry (all page entries will
* only store their sizes). */
SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream));
item_offset = (apr_off_t)value;
/* read all entries of this page */
last_revision = start_revision;
last_compound = 0;
/* Special case: empty pages. */
if (start_offset == next_offset)
{
/* Empty page. This only happens if the first entry of the next page
* also covers this page (and possibly more) completely. */
SVN_ERR(read_entry(rev_file->p2l_stream, &item_offset,
&last_revision, &last_compound, result));
}
else
{
/* Read non-empty page. */
do
{
SVN_ERR(read_entry(rev_file->p2l_stream, &item_offset,
&last_revision, &last_compound, result));
offset = packed_stream_offset(rev_file->p2l_stream);
}
while (offset < next_offset);
/* We should now be exactly at the next offset, i.e. the numbers in
* the stream cannot overlap into the next page description. */
if (offset != next_offset)
return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL,
_("P2L page description overlaps with next page description"));
/* if we haven't covered the cluster end yet, we must read the first
* entry of the next page */
if (item_offset < page_start + page_size)
{
SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream));
item_offset = (apr_off_t)value;
last_revision = start_revision;
last_compound = 0;
SVN_ERR(read_entry(rev_file->p2l_stream, &item_offset,
&last_revision, &last_compound, result));
}
}
*entries = result;
return SVN_NO_ERROR;
}
/* If it cannot be found in FS's caches, read the p2l index page selected
* by BATON->OFFSET from REV_FILE. Don't read the page if it precedes
* MIN_OFFSET. Set *END to TRUE if the caller should stop refeching.
*
* *BATON will be updated with the selected page's info and SCRATCH_POOL
* will be used for temporary allocations. If the data is already in the
* cache, decrease *LEAKING_BUCKET and increase it otherwise. With that
* pattern we will still read all pages from the block even if some of
* them survived in the cached.
*/
static svn_error_t *
prefetch_p2l_page(svn_boolean_t *end,
int *leaking_bucket,
svn_fs_t *fs,
svn_fs_fs__revision_file_t *rev_file,
p2l_page_info_baton_t *baton,
apr_off_t min_offset,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
svn_boolean_t already_cached;
apr_array_header_t *page;
svn_fs_fs__page_cache_key_t key = { 0 };
/* fetch the page info */
*end = FALSE;
baton->revision = baton->first_revision;
SVN_ERR(get_p2l_page_info(baton, rev_file, fs, scratch_pool));
if (baton->start_offset < min_offset || !rev_file->p2l_stream)
{
/* page outside limits -> stop prefetching */
*end = TRUE;
return SVN_NO_ERROR;
}
/* do we have that page in our caches already? */
assert(baton->first_revision <= APR_UINT32_MAX);
key.revision = (apr_uint32_t)baton->first_revision;
key.is_packed = svn_fs_fs__is_packed_rev(fs, baton->first_revision);
key.page = baton->page_no;
SVN_ERR(svn_cache__has_key(&already_cached, ffd->p2l_page_cache,
&key, scratch_pool));
/* yes, already cached */
if (already_cached)
{
/* stop prefetching if most pages are already cached. */
if (!--*leaking_bucket)
*end = TRUE;
return SVN_NO_ERROR;
}
++*leaking_bucket;
/* read from disk */
SVN_ERR(get_p2l_page(&page, rev_file, fs,
baton->first_revision,
baton->start_offset,
baton->next_offset,
baton->page_start,
baton->page_size,
scratch_pool));
/* and put it into our cache */
SVN_ERR(svn_cache__set(ffd->p2l_page_cache, &key, page, scratch_pool));
return SVN_NO_ERROR;
}
/* Lookup & construct the baton and key information that we will need for
* a P2L page cache lookup. We want the page covering OFFSET in the rev /
* pack file containing REVSION in FS. Return the results in *PAGE_INFO_P
* and *KEY_P. Read data through REV_FILE. Use SCRATCH_POOL for temporary
* allocations.
*/
static svn_error_t *
get_p2l_keys(p2l_page_info_baton_t *page_info_p,
svn_fs_fs__page_cache_key_t *key_p,
svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
svn_revnum_t revision,
apr_off_t offset,
apr_pool_t *scratch_pool)
{
p2l_page_info_baton_t page_info;
/* request info for the index pages that describes the pack / rev file
* contents at pack / rev file position OFFSET. */
page_info.offset = offset;
page_info.revision = revision;
SVN_ERR(get_p2l_page_info(&page_info, rev_file, fs, scratch_pool));
/* if the offset refers to a non-existent page, bail out */
if (page_info.page_count <= page_info.page_no)
return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL,
_("Offset %s too large in revision %ld"),
apr_off_t_toa(scratch_pool, offset), revision);
/* return results */
if (page_info_p)
*page_info_p = page_info;
/* construct cache key */
if (key_p)
{
svn_fs_fs__page_cache_key_t key = { 0 };
assert(page_info.first_revision <= APR_UINT32_MAX);
key.revision = (apr_uint32_t)page_info.first_revision;
key.is_packed = rev_file->is_packed;
key.page = page_info.page_no;
*key_p = key;
}
return SVN_NO_ERROR;
}
/* qsort-compatible compare function that compares the OFFSET of the
* svn_fs_fs__p2l_entry_t in *LHS with the apr_off_t in *RHS. */
static int
compare_start_p2l_entry(const void *lhs,
const void *rhs)
{
const svn_fs_fs__p2l_entry_t *entry = lhs;
apr_off_t start = *(const apr_off_t*)rhs;
apr_off_t diff = entry->offset - start;
/* restrict result to int */
return diff < 0 ? -1 : (diff == 0 ? 0 : 1);
}
/* From the PAGE_ENTRIES array of svn_fs_fs__p2l_entry_t, ordered
* by their OFFSET member, copy all elements overlapping the range
* [BLOCK_START, BLOCK_END) to ENTRIES. */
static void
append_p2l_entries(apr_array_header_t *entries,
apr_array_header_t *page_entries,
apr_off_t block_start,
apr_off_t block_end)
{
const svn_fs_fs__p2l_entry_t *entry;
int idx = svn_sort__bsearch_lower_bound(page_entries, &block_start,
compare_start_p2l_entry);
/* start at the first entry that overlaps with BLOCK_START */
if (idx > 0)
{
entry = &APR_ARRAY_IDX(page_entries, idx - 1, svn_fs_fs__p2l_entry_t);
if (entry->offset + entry->size > block_start)
--idx;
}
/* copy all entries covering the requested range */
for ( ; idx < page_entries->nelts; ++idx)
{
entry = &APR_ARRAY_IDX(page_entries, idx, svn_fs_fs__p2l_entry_t);
if (entry->offset >= block_end)
break;
APR_ARRAY_PUSH(entries, svn_fs_fs__p2l_entry_t) = *entry;
}
}
/* Auxiliary struct passed to p2l_entries_func selecting the relevant
* data range. */
typedef struct p2l_entries_baton_t
{
apr_off_t start;
apr_off_t end;
} p2l_entries_baton_t;
/* Implement svn_cache__partial_getter_func_t: extract p2l entries from
* the page in DATA which overlap the p2l_entries_baton_t in BATON.
* The target array is already provided in *OUT.
*/
static svn_error_t *
p2l_entries_func(void **out,
const void *data,
apr_size_t data_len,
void *baton,
apr_pool_t *result_pool)
{
apr_array_header_t *entries = *(apr_array_header_t **)out;
const apr_array_header_t *raw_page = data;
p2l_entries_baton_t *block = baton;
/* Make PAGE a readable APR array. */
apr_array_header_t page = *raw_page;
page.elts = (void *)svn_temp_deserializer__ptr(raw_page,
(const void * const *)&raw_page->elts);
/* append relevant information to result */
append_p2l_entries(entries, &page, block->start, block->end);
return SVN_NO_ERROR;
}
/* Body of svn_fs_fs__p2l_index_lookup. However, do a single index page
* lookup and append the result to the ENTRIES array provided by the caller.
* Use successive calls to cover larger ranges.
*/
static svn_error_t *
p2l_index_lookup(apr_array_header_t *entries,
svn_fs_fs__revision_file_t *rev_file,
svn_fs_t *fs,
svn_revnum_t revision,
apr_off_t block_start,
apr_off_t block_end,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
svn_fs_fs__page_cache_key_t key;
svn_boolean_t is_cached = FALSE;
p2l_page_info_baton_t page_info;
apr_array_header_t *local_result = entries;
/* baton selecting the relevant entries from the one page we access */
p2l_entries_baton_t block;
block.start = block_start;
block.end = block_end;
/* if we requested an empty range, the result would be empty */
SVN_ERR_ASSERT(block_start < block_end);
/* look for the fist page of the range in our cache */
SVN_ERR(get_p2l_keys(&page_info, &key, rev_file, fs, revision, block_start,
scratch_pool));
SVN_ERR(svn_cache__get_partial((void**)&local_result, &is_cached,
ffd->p2l_page_cache, &key, p2l_entries_func,
&block, scratch_pool));
if (!is_cached)
{
svn_boolean_t end;
apr_pool_t *iterpool = svn_pool_create(scratch_pool);
apr_off_t original_page_start = page_info.page_start;
int leaking_bucket = 4;
p2l_page_info_baton_t prefetch_info = page_info;
apr_array_header_t *page_entries;
apr_off_t max_offset
= APR_ALIGN(page_info.next_offset, ffd->block_size);
apr_off_t min_offset
= APR_ALIGN(page_info.start_offset, ffd->block_size) - ffd->block_size;
/* Since we read index data in larger chunks, we probably got more
* page data than we requested. Parse & cache that until either we
* encounter pages already cached or reach the end of the buffer.
*/
/* pre-fetch preceding pages */
if (ffd->use_block_read)
{
end = FALSE;
prefetch_info.offset = original_page_start;
while (prefetch_info.offset >= prefetch_info.page_size && !end)
{
svn_pool_clear(iterpool);
prefetch_info.offset -= prefetch_info.page_size;
SVN_ERR(prefetch_p2l_page(&end, &leaking_bucket, fs, rev_file,
&prefetch_info, min_offset,
iterpool));
}
}
/* fetch page from disk and put it into the cache */
SVN_ERR(get_p2l_page(&page_entries, rev_file, fs,
page_info.first_revision,
page_info.start_offset,
page_info.next_offset,
page_info.page_start,
page_info.page_size, iterpool));
/* The last cache entry must not end beyond the range covered by
* this index. The same applies for any subset of entries. */
if (page_entries->nelts)
{
const svn_fs_fs__p2l_entry_t *entry
= &APR_ARRAY_IDX(page_entries, page_entries->nelts - 1,
svn_fs_fs__p2l_entry_t);
if ( entry->offset + entry->size
> page_info.page_size * page_info.page_count)
return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL,
_("Last P2L index entry extends beyond "
"the last page in revision %ld."),
revision);
}
SVN_ERR(svn_cache__set(ffd->p2l_page_cache, &key, page_entries,
iterpool));
/* append relevant information to result */
append_p2l_entries(entries, page_entries, block_start, block_end);
/* pre-fetch following pages */
if (ffd->use_block_read)
{
end = FALSE;
leaking_bucket = 4;
prefetch_info = page_info;
prefetch_info.offset = original_page_start;
while ( prefetch_info.next_offset < max_offset
&& prefetch_info.page_no + 1 < prefetch_info.page_count
&& !end)
{
svn_pool_clear(iterpool);
prefetch_info.offset += prefetch_info.page_size;
SVN_ERR(prefetch_p2l_page(&end, &leaking_bucket, fs, rev_file,
&prefetch_info, min_offset,
iterpool));
}
}
svn_pool_destroy(iterpool);
}
/* We access a valid page (otherwise, we had seen an error in the
* get_p2l_keys request). Hence, at least one entry must be found. */
SVN_ERR_ASSERT(entries->nelts > 0);
/* Add an "unused" entry if it extends beyond the end of the data file.
* Since the index page size might be smaller than the current data
* read block size, the trailing "unused" entry in this index may not
* fully cover the end of the last block. */
if (page_info.page_no + 1 >= page_info.page_count)
{
svn_fs_fs__p2l_entry_t *entry
= &APR_ARRAY_IDX(entries, entries->nelts-1, svn_fs_fs__p2l_entry_t);
apr_off_t entry_end = entry->offset + entry->size;
if (entry_end < block_end)
{
if (entry->type == SVN_FS_FS__ITEM_TYPE_UNUSED)
{
/* extend the terminal filler */
entry->size = block_end - entry->offset;
}
else
{
/* No terminal filler. Add one. */
entry = apr_array_push(entries);
entry->offset = entry_end;
entry->size = block_end - entry_end;
entry->type = SVN_FS_FS__ITEM_TYPE_UNUSED;
entry->fnv1_checksum = 0;
entry->item.revision = SVN_INVALID_REVNUM;
entry->item.number = SVN_FS_FS__ITEM_INDEX_UNUSED;
}
}
}
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__p2l_index_lookup(apr_array_header_t **entries,
svn_fs_t *fs,
svn_fs_fs__revision_file_t *rev_file,
svn_revnum_t revision,
apr_off_t block_start,
apr_off_t block_size,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
apr_off_t block_end = block_start + block_size;
/* the receiving container */
int last_count = 0;
apr_array_header_t *result = apr_array_make(result_pool, 16,
sizeof(svn_fs_fs__p2l_entry_t));
/* Fetch entries page-by-page. Since the p2l index is supposed to cover
* every single byte in the rev / pack file - even unused sections -
* every iteration must result in some progress. */
while (block_start < block_end)
{
svn_fs_fs__p2l_entry_t *entry;
SVN_ERR(p2l_index_lookup(result, rev_file, fs, revision, block_start,
block_end, scratch_pool));
SVN_ERR_ASSERT(result->nelts > 0);
/* continue directly behind last item */
entry = &APR_ARRAY_IDX(result, result->nelts-1, svn_fs_fs__p2l_entry_t);
block_start = entry->offset + entry->size;
/* Some paranoia check. Successive iterations should never return
* duplicates but if it did, we might get into trouble later on. */
if (last_count > 0 && last_count < result->nelts)
{
entry = &APR_ARRAY_IDX(result, last_count - 1,
svn_fs_fs__p2l_entry_t);
SVN_ERR_ASSERT(APR_ARRAY_IDX(result, last_count,
svn_fs_fs__p2l_entry_t).offset
>= entry->offset + entry->size);
}
last_count = result->nelts;
}
*entries = result;
return SVN_NO_ERROR;
}
/* compare_fn_t comparing a svn_fs_fs__p2l_entry_t at LHS with an offset
* RHS.
*/
static int
compare_p2l_entry_offsets(const void *lhs, const void *rhs)
{
const svn_fs_fs__p2l_entry_t *entry = (const svn_fs_fs__p2l_entry_t *)lhs;
apr_off_t offset = *(const apr_off_t *)rhs;
return entry->offset < offset ? -1 : (entry->offset == offset ? 0 : 1);
}
/* Cached data extraction utility. DATA is a P2L index page, e.g. an APR
* array of svn_fs_fs__p2l_entry_t elements. Return the entry for the item,
* allocated in RESULT_POOL, starting at OFFSET or NULL if that's not an
* the start offset of any item. Use SCRATCH_POOL for temporary allocations.
*/
static svn_fs_fs__p2l_entry_t *
get_p2l_entry_from_cached_page(const void *data,
apr_uint64_t offset,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
/* resolve all pointer values of in-cache data */
const apr_array_header_t *page = data;
apr_array_header_t *entries = apr_pmemdup(scratch_pool, page,
sizeof(*page));
svn_fs_fs__p2l_entry_t *entry;
entries->elts = (char *)svn_temp_deserializer__ptr(page,
(const void *const *)&page->elts);
/* search of the offset we want */
entry = svn_sort__array_lookup(entries, &offset, NULL,
(int (*)(const void *, const void *))compare_p2l_entry_offsets);
/* return it, if it is a perfect match */
return entry ? apr_pmemdup(result_pool, entry, sizeof(*entry)) : NULL;
}
/* Implements svn_cache__partial_getter_func_t for P2L index pages, copying
* the entry for the apr_off_t at BATON into *OUT. *OUT will be NULL if
* there is no matching entry in the index page at DATA.
*/
static svn_error_t *
p2l_entry_lookup_func(void **out,
const void *data,
apr_size_t data_len,
void *baton,
apr_pool_t *result_pool)
{
svn_fs_fs__p2l_entry_t *entry
= get_p2l_entry_from_cached_page(data, *(apr_off_t *)baton, result_pool,
result_pool);
*out = entry && entry->offset == *(apr_off_t *)baton
? apr_pmemdup(result_pool, entry, sizeof(*entry))
: NULL;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__p2l_entry_lookup(svn_fs_fs__p2l_entry_t **entry_p,
svn_fs_t *fs,
svn_fs_fs__revision_file_t *rev_file,
svn_revnum_t revision,
apr_off_t offset,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
svn_fs_fs__page_cache_key_t key = { 0 };
svn_boolean_t is_cached = FALSE;
p2l_page_info_baton_t page_info;
*entry_p = NULL;
/* look for this info in our cache */
SVN_ERR(get_p2l_keys(&page_info, &key, rev_file, fs, revision, offset,
scratch_pool));
SVN_ERR(svn_cache__get_partial((void**)entry_p, &is_cached,
ffd->p2l_page_cache, &key,
p2l_entry_lookup_func, &offset,
result_pool));
if (!is_cached)
{
/* do a standard index lookup. This is will automatically prefetch
* data to speed up future lookups. */
apr_array_header_t *entries = apr_array_make(result_pool, 1,
sizeof(**entry_p));
SVN_ERR(p2l_index_lookup(entries, rev_file, fs, revision, offset,
offset + 1, scratch_pool));
/* Find the entry that we want. */
*entry_p = svn_sort__array_lookup(entries, &offset, NULL,
(int (*)(const void *, const void *))compare_p2l_entry_offsets);
}
return SVN_NO_ERROR;
}
/* Implements svn_cache__partial_getter_func_t for P2L headers, setting *OUT
* to the largest the first offset not covered by this P2L index.
*/
static svn_error_t *
p2l_get_max_offset_func(void **out,
const void *data,
apr_size_t data_len,
void *baton,
apr_pool_t *result_pool)
{
const p2l_header_t *header = data;
apr_off_t max_offset = header->file_size;
*out = apr_pmemdup(result_pool, &max_offset, sizeof(max_offset));
return SVN_NO_ERROR;
}
/* Core functionality of to svn_fs_fs__p2l_get_max_offset with identical
* signature. */
static svn_error_t *
p2l_get_max_offset(apr_off_t *offset,
svn_fs_t *fs,
svn_fs_fs__revision_file_t *rev_file,
svn_revnum_t revision,
apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
p2l_header_t *header;
svn_boolean_t is_cached = FALSE;
apr_off_t *offset_p;
/* look for the header data in our cache */
pair_cache_key_t key;
key.revision = rev_file->start_revision;
key.second = rev_file->is_packed;
SVN_ERR(svn_cache__get_partial((void **)&offset_p, &is_cached,
ffd->p2l_header_cache, &key,
p2l_get_max_offset_func, NULL,
scratch_pool));
if (is_cached)
{
*offset = *offset_p;
return SVN_NO_ERROR;
}
SVN_ERR(get_p2l_header(&header, rev_file, fs, revision, scratch_pool,
scratch_pool));
*offset = header->file_size;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__p2l_get_max_offset(apr_off_t *offset,
svn_fs_t *fs,
svn_fs_fs__revision_file_t *rev_file,
svn_revnum_t revision,
apr_pool_t *scratch_pool)
{
return svn_error_trace(p2l_get_max_offset(offset, fs, rev_file, revision,
scratch_pool));
}
/* Calculate the FNV1 checksum over the offset range in REV_FILE, covered by
* ENTRY. Store the result in ENTRY->FNV1_CHECKSUM. Use SCRATCH_POOL for
* temporary allocations. */
static svn_error_t *
calc_fnv1(svn_fs_fs__p2l_entry_t *entry,
svn_fs_fs__revision_file_t *rev_file,
apr_pool_t *scratch_pool)
{
unsigned char buffer[4096];
svn_checksum_t *checksum;
svn_checksum_ctx_t *context
= svn_checksum_ctx_create(svn_checksum_fnv1a_32x4, scratch_pool);
apr_off_t size = entry->size;
/* Special rules apply to unused sections / items. The data must be a
* sequence of NUL bytes (not checked here) and the checksum is fixed to 0.
*/
if (entry->type == SVN_FS_FS__ITEM_TYPE_UNUSED)
{
entry->fnv1_checksum = 0;
return SVN_NO_ERROR;
}
/* Read the block and feed it to the checksum calculator. */
SVN_ERR(svn_io_file_seek(rev_file->file, APR_SET, &entry->offset,
scratch_pool));
while (size > 0)
{
apr_size_t to_read = size > sizeof(buffer)
? sizeof(buffer)
: (apr_size_t)size;
SVN_ERR(svn_io_file_read_full2(rev_file->file, buffer, to_read, NULL,
NULL, scratch_pool));
SVN_ERR(svn_checksum_update(context, buffer, to_read));
size -= to_read;
}
/* Store final checksum in ENTRY. */
SVN_ERR(svn_checksum_final(&checksum, context, scratch_pool));
entry->fnv1_checksum = ntohl(*(const apr_uint32_t *)checksum->digest);
return SVN_NO_ERROR;
}
/*
* Index (re-)creation utilities.
*/
svn_error_t *
svn_fs_fs__p2l_index_from_p2l_entries(const char **protoname,
svn_fs_t *fs,
svn_fs_fs__revision_file_t *rev_file,
apr_array_header_t *entries,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
apr_file_t *proto_index;
/* Use a subpool for immediate temp file cleanup at the end of this
* function. */
apr_pool_t *iterpool = svn_pool_create(scratch_pool);
int i;
/* Create a proto-index file. */
SVN_ERR(svn_io_open_unique_file3(NULL, protoname, NULL,
svn_io_file_del_on_pool_cleanup,
result_pool, scratch_pool));
SVN_ERR(svn_fs_fs__p2l_proto_index_open(&proto_index, *protoname,
scratch_pool));
/* Write ENTRIES to proto-index file and calculate checksums as we go. */
for (i = 0; i < entries->nelts; ++i)
{
svn_fs_fs__p2l_entry_t *entry
= APR_ARRAY_IDX(entries, i, svn_fs_fs__p2l_entry_t *);
svn_pool_clear(iterpool);
SVN_ERR(calc_fnv1(entry, rev_file, iterpool));
SVN_ERR(svn_fs_fs__p2l_proto_index_add_entry(proto_index, entry,
iterpool));
}
/* Convert proto-index into final index and move it into position.
* Note that REV_FILE contains the start revision of the shard file if it
* has been packed while REVISION may be somewhere in the middle. For
* non-packed shards, they will have identical values. */
SVN_ERR(svn_io_file_close(proto_index, iterpool));
/* Temp file cleanup. */
svn_pool_destroy(iterpool);
return SVN_NO_ERROR;
}
/* A svn_sort__array compatible comparator function, sorting the
* svn_fs_fs__p2l_entry_t** given in LHS, RHS by revision. */
static int
compare_p2l_entry_revision(const void *lhs,
const void *rhs)
{
const svn_fs_fs__p2l_entry_t *lhs_entry
=*(const svn_fs_fs__p2l_entry_t *const *)lhs;
const svn_fs_fs__p2l_entry_t *rhs_entry
=*(const svn_fs_fs__p2l_entry_t *const *)rhs;
if (lhs_entry->item.revision < rhs_entry->item.revision)
return -1;
return lhs_entry->item.revision == rhs_entry->item.revision ? 0 : 1;
}
svn_error_t *
svn_fs_fs__l2p_index_from_p2l_entries(const char **protoname,
svn_fs_t *fs,
apr_array_header_t *entries,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
apr_file_t *proto_index;
/* Use a subpool for immediate temp file cleanup at the end of this
* function. */
apr_pool_t *iterpool = svn_pool_create(scratch_pool);
int i;
svn_revnum_t last_revision = SVN_INVALID_REVNUM;
/* L2P index must be written in revision order.
* Sort ENTRIES accordingly. */
svn_sort__array(entries, compare_p2l_entry_revision);
/* Create the temporary proto-rev file. */
SVN_ERR(svn_io_open_unique_file3(NULL, protoname, NULL,
svn_io_file_del_on_pool_cleanup,
result_pool, scratch_pool));
SVN_ERR(svn_fs_fs__l2p_proto_index_open(&proto_index, *protoname,
scratch_pool));
/* Write all entries. */
for (i = 0; i < entries->nelts; ++i)
{
const svn_fs_fs__p2l_entry_t *entry
= APR_ARRAY_IDX(entries, i, const svn_fs_fs__p2l_entry_t *);
svn_pool_clear(iterpool);
if (entry->type == SVN_FS_FS__ITEM_TYPE_UNUSED)
continue;
if (last_revision != entry->item.revision)
{
SVN_ERR(svn_fs_fs__l2p_proto_index_add_revision(proto_index,
scratch_pool));
last_revision = entry->item.revision;
}
SVN_ERR(svn_fs_fs__l2p_proto_index_add_entry(proto_index,
entry->offset,
entry->item.number,
iterpool));
}
/* Convert proto-index into final index and move it into position. */
SVN_ERR(svn_io_file_close(proto_index, iterpool));
/* Temp file cleanup. */
svn_pool_destroy(iterpool);
return SVN_NO_ERROR;
}
/*
* Standard (de-)serialization functions
*/
svn_error_t *
svn_fs_fs__serialize_l2p_header(void **data,
apr_size_t *data_len,
void *in,
apr_pool_t *pool)
{
l2p_header_t *header = in;
svn_temp_serializer__context_t *context;
svn_stringbuf_t *serialized;
apr_size_t page_count = header->page_table_index[header->revision_count];
apr_size_t page_table_size = page_count * sizeof(*header->page_table);
apr_size_t index_size
= (header->revision_count + 1) * sizeof(*header->page_table_index);
apr_size_t data_size = sizeof(*header) + index_size + page_table_size;
/* serialize header and all its elements */
context = svn_temp_serializer__init(header,
sizeof(*header),
data_size + 32,
pool);
/* page table index array */
svn_temp_serializer__add_leaf(context,
(const void * const *)&header->page_table_index,
index_size);
/* page table array */
svn_temp_serializer__add_leaf(context,
(const void * const *)&header->page_table,
page_table_size);
/* return the serialized result */
serialized = svn_temp_serializer__get(context);
*data = serialized->data;
*data_len = serialized->len;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__deserialize_l2p_header(void **out,
void *data,
apr_size_t data_len,
apr_pool_t *pool)
{
l2p_header_t *header = (l2p_header_t *)data;
/* resolve the pointers in the struct */
svn_temp_deserializer__resolve(header, (void**)&header->page_table_index);
svn_temp_deserializer__resolve(header, (void**)&header->page_table);
/* done */
*out = header;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__serialize_l2p_page(void **data,
apr_size_t *data_len,
void *in,
apr_pool_t *pool)
{
l2p_page_t *page = in;
svn_temp_serializer__context_t *context;
svn_stringbuf_t *serialized;
apr_size_t of_table_size = page->entry_count * sizeof(*page->offsets);
/* serialize struct and all its elements */
context = svn_temp_serializer__init(page,
sizeof(*page),
of_table_size + sizeof(*page) + 32,
pool);
/* offsets and sub_items arrays */
svn_temp_serializer__add_leaf(context,
(const void * const *)&page->offsets,
of_table_size);
/* return the serialized result */
serialized = svn_temp_serializer__get(context);
*data = serialized->data;
*data_len = serialized->len;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__deserialize_l2p_page(void **out,
void *data,
apr_size_t data_len,
apr_pool_t *pool)
{
l2p_page_t *page = data;
/* resolve the pointers in the struct */
svn_temp_deserializer__resolve(page, (void**)&page->offsets);
/* done */
*out = page;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__serialize_p2l_header(void **data,
apr_size_t *data_len,
void *in,
apr_pool_t *pool)
{
p2l_header_t *header = in;
svn_temp_serializer__context_t *context;
svn_stringbuf_t *serialized;
apr_size_t table_size = (header->page_count + 1) * sizeof(*header->offsets);
/* serialize header and all its elements */
context = svn_temp_serializer__init(header,
sizeof(*header),
table_size + sizeof(*header) + 32,
pool);
/* offsets array */
svn_temp_serializer__add_leaf(context,
(const void * const *)&header->offsets,
table_size);
/* return the serialized result */
serialized = svn_temp_serializer__get(context);
*data = serialized->data;
*data_len = serialized->len;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__deserialize_p2l_header(void **out,
void *data,
apr_size_t data_len,
apr_pool_t *pool)
{
p2l_header_t *header = data;
/* resolve the only pointer in the struct */
svn_temp_deserializer__resolve(header, (void**)&header->offsets);
/* done */
*out = header;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__serialize_p2l_page(void **data,
apr_size_t *data_len,
void *in,
apr_pool_t *pool)
{
apr_array_header_t *page = in;
svn_temp_serializer__context_t *context;
svn_stringbuf_t *serialized;
apr_size_t table_size = page->elt_size * page->nelts;
/* serialize array header and all its elements */
context = svn_temp_serializer__init(page,
sizeof(*page),
table_size + sizeof(*page) + 32,
pool);
/* items in the array */
svn_temp_serializer__add_leaf(context,
(const void * const *)&page->elts,
table_size);
/* return the serialized result */
serialized = svn_temp_serializer__get(context);
*data = serialized->data;
*data_len = serialized->len;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_fs__deserialize_p2l_page(void **out,
void *data,
apr_size_t data_len,
apr_pool_t *pool)
{
apr_array_header_t *page = (apr_array_header_t *)data;
/* resolve the only pointer in the struct */
svn_temp_deserializer__resolve(page, (void**)&page->elts);
/* patch up members */
page->pool = pool;
page->nalloc = page->nelts;
/* done */
*out = page;
return SVN_NO_ERROR;
}