X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;ds=sidebyside;f=src%2Fjournal%2Fjournal-file.c;h=ec12e891a791a8d0b3b07f992b4bd21c350ef244;hb=fc07d5d3a982e59d984d6be54342a18028faf7be;hp=1736ff57af795b08b69cf4a943f1c4278061fd6c;hpb=805d14864f8d6936202b85730a7d8a77317d1202;p=elogind.git diff --git a/src/journal/journal-file.c b/src/journal/journal-file.c index 1736ff57a..ec12e891a 100644 --- a/src/journal/journal-file.c +++ b/src/journal/journal-file.c @@ -26,7 +26,9 @@ #include #include #include +#include +#include "btrfs-util.h" #include "journal-def.h" #include "journal-file.h" #include "journal-authenticate.h" @@ -67,6 +69,9 @@ /* How much to increase the journal file size at once each time we allocate something new. */ #define FILE_SIZE_INCREASE (8ULL*1024ULL*1024ULL) /* 8MB */ +/* Reread fstat() of the file for detecting deletions at least this often */ +#define LAST_STAT_REFRESH_USEC (5*USEC_PER_SEC) + /* The mmap context to use for the header we pick as one above the last defined typed */ #define CONTEXT_HEADER _OBJECT_TYPE_MAX @@ -137,6 +142,18 @@ void journal_file_close(JournalFile *f) { if (f->mmap && f->fd >= 0) mmap_cache_close_fd(f->mmap, f->fd); + if (f->fd >= 0 && f->defrag_on_close) { + + /* Be friendly to btrfs: turn COW back on again now, + * and defragment the file. We won't write to the file + * ever again, hence remove all fragmentation, and + * reenable all the good bits COW usually provides + * (such as data checksumming). */ + + (void) chattr_fd(f->fd, false, FS_NOCOW_FL); + (void) btrfs_defrag_fd(f->fd); + } + safe_close(f->fd); free(f->path); @@ -306,7 +323,7 @@ static int journal_file_verify_header(JournalFile *f) { } else if (state == STATE_ARCHIVED) return -ESHUTDOWN; else if (state != STATE_OFFLINE) { - log_debug("Journal file %s has unknown state %u.", f->path, state); + log_debug("Journal file %s has unknown state %i.", f->path, state); return -EBUSY; } } @@ -319,6 +336,22 @@ static int journal_file_verify_header(JournalFile *f) { return 0; } +static int journal_file_fstat(JournalFile *f) { + assert(f); + assert(f->fd >= 0); + + if (fstat(f->fd, &f->last_stat) < 0) + return -errno; + + f->last_stat_usec = now(CLOCK_MONOTONIC); + + /* Refuse appending to files that are already deleted */ + if (f->last_stat.st_nlink <= 0) + return -EIDRM; + + return 0; +} + static int journal_file_allocate(JournalFile *f, uint64_t offset, uint64_t size) { uint64_t old_size, new_size; int r; @@ -340,8 +373,21 @@ static int journal_file_allocate(JournalFile *f, uint64_t offset, uint64_t size) if (new_size < le64toh(f->header->header_size)) new_size = le64toh(f->header->header_size); - if (new_size <= old_size) - return 0; + if (new_size <= old_size) { + + /* We already pre-allocated enough space, but before + * we write to it, let's check with fstat() if the + * file got deleted, in order make sure we don't throw + * away the data immediately. Don't check fstat() for + * all writes though, but only once ever 10s. */ + + if (f->last_stat_usec + LAST_STAT_REFRESH_USEC > now(CLOCK_MONOTONIC)) + return 0; + + return journal_file_fstat(f); + } + + /* Allocate more space. */ if (f->metrics.max_size > 0 && new_size > f->metrics.max_size) return -E2BIG; @@ -376,12 +422,9 @@ static int journal_file_allocate(JournalFile *f, uint64_t offset, uint64_t size) if (r != 0) return -r; - if (fstat(f->fd, &f->last_stat) < 0) - return -errno; - f->header->arena_size = htole64(new_size - le64toh(f->header->header_size)); - return 0; + return journal_file_fstat(f); } static unsigned type_to_context(ObjectType type) { @@ -392,6 +435,8 @@ static unsigned type_to_context(ObjectType type) { } static int journal_file_move_to(JournalFile *f, ObjectType type, bool keep_always, uint64_t offset, uint64_t size, void **ret) { + int r; + assert(f); assert(ret); @@ -403,8 +448,11 @@ static int journal_file_move_to(JournalFile *f, ObjectType type, bool keep_alway /* Hmm, out of range? Let's refresh the fstat() data * first, before we trust that check. */ - if (fstat(f->fd, &f->last_stat) < 0 || - offset + size > (uint64_t) f->last_stat.st_size) + r = journal_file_fstat(f); + if (r < 0) + return r; + + if (offset + size > (uint64_t) f->last_stat.st_size) return -EADDRNOTAVAIL; } @@ -2369,7 +2417,7 @@ void journal_file_dump(JournalFile *f) { break; default: - printf("Type: unknown (%u)\n", o->object.type); + printf("Type: unknown (%i)\n", o->object.type); break; } @@ -2548,12 +2596,23 @@ int journal_file_open( goto fail; } - if (fstat(f->fd, &f->last_stat) < 0) { - r = -errno; + r = journal_file_fstat(f); + if (r < 0) goto fail; - } if (f->last_stat.st_size == 0 && f->writable) { + + /* Before we write anything, turn off COW logic. Given + * our write pattern that is quite unfriendly to COW + * file systems this should greatly improve + * performance on COW file systems, such as btrfs, at + * the expense of data integrity features (which + * shouldn't be too bad, given that we do our own + * checksumming). */ + r = chattr_fd(f->fd, true, FS_NOCOW_FL); + if (r < 0) + log_warning_errno(errno, "Failed to set file attributes: %m"); + /* Let's attach the creation time to the journal file, * so that the vacuuming code knows the age of this * file even if the file might end up corrupted one @@ -2564,7 +2623,7 @@ int journal_file_open( * attributes are not supported we'll just skip this, * and rely solely on mtime/atime/ctime of the file. */ - fd_setcrtime(f->fd, now(CLOCK_REALTIME)); + fd_setcrtime(f->fd, 0); #ifdef HAVE_GCRYPT /* Try to load the FSPRG state, and if we can't, then @@ -2580,10 +2639,9 @@ int journal_file_open( if (r < 0) goto fail; - if (fstat(f->fd, &f->last_stat) < 0) { - r = -errno; + r = journal_file_fstat(f); + if (r < 0) goto fail; - } newly_created = true; } @@ -2700,12 +2758,20 @@ int journal_file_rotate(JournalFile **f, bool compress, bool seal) { if (r < 0) return -ENOMEM; + /* Try to rename the file to the archived version. If the file + * already was deleted, we'll get ENOENT, let's ignore that + * case. */ r = rename(old_file->path, p); - if (r < 0) + if (r < 0 && errno != ENOENT) return -errno; old_file->header->state = STATE_ARCHIVED; + /* Currently, btrfs is not very good with out write patterns + * and fragments heavily. Let's defrag our journal files when + * we archive them */ + old_file->defrag_on_close = true; + r = journal_file_open(old_file->path, old_file->flags, old_file->mode, compress, seal, NULL, old_file->mmap, old_file, &new_file); journal_file_close(old_file); @@ -2736,7 +2802,8 @@ int journal_file_open_reliably( r != -EPROTONOSUPPORT && /* incompatible feature */ r != -EBUSY && /* unclean shutdown */ r != -ESHUTDOWN && /* already archived */ - r != -EIO /* IO error, including SIGBUS on mmap */) + r != -EIO && /* IO error, including SIGBUS on mmap */ + r != -EIDRM /* File has been deleted */) return r; if ((flags & O_ACCMODE) == O_RDONLY) @@ -2761,6 +2828,12 @@ int journal_file_open_reliably( if (r < 0) return -errno; + /* btrfs doesn't cope well with our write pattern and + * fragments heavily. Let's defrag all files we rotate */ + + (void) chattr_path(p, false, FS_NOCOW_FL); + (void) btrfs_defrag(p); + log_warning("File %s corrupted or uncleanly shut down, renaming and replacing.", fname); return journal_file_open(fname, flags, mode, compress, seal,