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![Joern Engel](/assets/img/avatar_default.png)
Can be necessary if an inode gets deleted (through -ENOSPC) before being written. Might be better to move this into logfs_write_rec(), but for now go with the stupid&safe patch. Signed-off-by: Joern Engel <joern@logfs.org>
2294 lines
56 KiB
C
2294 lines
56 KiB
C
/*
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* fs/logfs/readwrite.c
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*
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* As should be obvious for Linux kernel code, license is GPLv2
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*
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* Copyright (c) 2005-2008 Joern Engel <joern@logfs.org>
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*
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*
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* Actually contains five sets of very similar functions:
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* read read blocks from a file
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* seek_hole find next hole
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* seek_data find next data block
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* valid check whether a block still belongs to a file
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* write write blocks to a file
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* delete delete a block (for directories and ifile)
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* rewrite move existing blocks of a file to a new location (gc helper)
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* truncate truncate a file
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*/
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#include "logfs.h"
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#include <linux/sched.h>
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#include <linux/slab.h>
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static u64 adjust_bix(u64 bix, level_t level)
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{
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switch (level) {
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case 0:
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return bix;
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case LEVEL(1):
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return max_t(u64, bix, I0_BLOCKS);
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case LEVEL(2):
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return max_t(u64, bix, I1_BLOCKS);
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case LEVEL(3):
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return max_t(u64, bix, I2_BLOCKS);
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case LEVEL(4):
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return max_t(u64, bix, I3_BLOCKS);
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case LEVEL(5):
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return max_t(u64, bix, I4_BLOCKS);
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default:
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WARN_ON(1);
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return bix;
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}
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}
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static inline u64 maxbix(u8 height)
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{
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return 1ULL << (LOGFS_BLOCK_BITS * height);
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}
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/**
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* The inode address space is cut in two halves. Lower half belongs to data
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* pages, upper half to indirect blocks. If the high bit (INDIRECT_BIT) is
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* set, the actual block index (bix) and level can be derived from the page
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* index.
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*
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* The lowest three bits of the block index are set to 0 after packing and
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* unpacking. Since the lowest n bits (9 for 4KiB blocksize) are ignored
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* anyway this is harmless.
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*/
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#define ARCH_SHIFT (BITS_PER_LONG - 32)
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#define INDIRECT_BIT (0x80000000UL << ARCH_SHIFT)
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#define LEVEL_SHIFT (28 + ARCH_SHIFT)
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static inline pgoff_t first_indirect_block(void)
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{
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return INDIRECT_BIT | (1ULL << LEVEL_SHIFT);
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}
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pgoff_t logfs_pack_index(u64 bix, level_t level)
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{
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pgoff_t index;
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BUG_ON(bix >= INDIRECT_BIT);
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if (level == 0)
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return bix;
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index = INDIRECT_BIT;
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index |= (__force long)level << LEVEL_SHIFT;
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index |= bix >> ((__force u8)level * LOGFS_BLOCK_BITS);
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return index;
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}
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void logfs_unpack_index(pgoff_t index, u64 *bix, level_t *level)
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{
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u8 __level;
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if (!(index & INDIRECT_BIT)) {
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*bix = index;
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*level = 0;
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return;
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}
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__level = (index & ~INDIRECT_BIT) >> LEVEL_SHIFT;
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*level = LEVEL(__level);
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*bix = (index << (__level * LOGFS_BLOCK_BITS)) & ~INDIRECT_BIT;
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*bix = adjust_bix(*bix, *level);
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return;
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}
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#undef ARCH_SHIFT
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#undef INDIRECT_BIT
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#undef LEVEL_SHIFT
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/*
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* Time is stored as nanoseconds since the epoch.
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*/
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static struct timespec be64_to_timespec(__be64 betime)
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{
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return ns_to_timespec(be64_to_cpu(betime));
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}
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static __be64 timespec_to_be64(struct timespec tsp)
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{
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return cpu_to_be64((u64)tsp.tv_sec * NSEC_PER_SEC + tsp.tv_nsec);
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}
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static void logfs_disk_to_inode(struct logfs_disk_inode *di, struct inode*inode)
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{
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struct logfs_inode *li = logfs_inode(inode);
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int i;
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inode->i_mode = be16_to_cpu(di->di_mode);
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li->li_height = di->di_height;
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li->li_flags = be32_to_cpu(di->di_flags);
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inode->i_uid = be32_to_cpu(di->di_uid);
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inode->i_gid = be32_to_cpu(di->di_gid);
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inode->i_size = be64_to_cpu(di->di_size);
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logfs_set_blocks(inode, be64_to_cpu(di->di_used_bytes));
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inode->i_atime = be64_to_timespec(di->di_atime);
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inode->i_ctime = be64_to_timespec(di->di_ctime);
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inode->i_mtime = be64_to_timespec(di->di_mtime);
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set_nlink(inode, be32_to_cpu(di->di_refcount));
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inode->i_generation = be32_to_cpu(di->di_generation);
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switch (inode->i_mode & S_IFMT) {
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case S_IFSOCK: /* fall through */
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case S_IFBLK: /* fall through */
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case S_IFCHR: /* fall through */
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case S_IFIFO:
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inode->i_rdev = be64_to_cpu(di->di_data[0]);
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break;
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case S_IFDIR: /* fall through */
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case S_IFREG: /* fall through */
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case S_IFLNK:
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for (i = 0; i < LOGFS_EMBEDDED_FIELDS; i++)
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li->li_data[i] = be64_to_cpu(di->di_data[i]);
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break;
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default:
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BUG();
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}
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}
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static void logfs_inode_to_disk(struct inode *inode, struct logfs_disk_inode*di)
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{
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struct logfs_inode *li = logfs_inode(inode);
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int i;
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di->di_mode = cpu_to_be16(inode->i_mode);
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di->di_height = li->li_height;
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di->di_pad = 0;
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di->di_flags = cpu_to_be32(li->li_flags);
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di->di_uid = cpu_to_be32(inode->i_uid);
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di->di_gid = cpu_to_be32(inode->i_gid);
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di->di_size = cpu_to_be64(i_size_read(inode));
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di->di_used_bytes = cpu_to_be64(li->li_used_bytes);
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di->di_atime = timespec_to_be64(inode->i_atime);
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di->di_ctime = timespec_to_be64(inode->i_ctime);
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di->di_mtime = timespec_to_be64(inode->i_mtime);
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di->di_refcount = cpu_to_be32(inode->i_nlink);
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di->di_generation = cpu_to_be32(inode->i_generation);
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switch (inode->i_mode & S_IFMT) {
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case S_IFSOCK: /* fall through */
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case S_IFBLK: /* fall through */
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case S_IFCHR: /* fall through */
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case S_IFIFO:
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di->di_data[0] = cpu_to_be64(inode->i_rdev);
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break;
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case S_IFDIR: /* fall through */
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case S_IFREG: /* fall through */
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case S_IFLNK:
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for (i = 0; i < LOGFS_EMBEDDED_FIELDS; i++)
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di->di_data[i] = cpu_to_be64(li->li_data[i]);
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break;
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default:
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BUG();
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}
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}
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static void __logfs_set_blocks(struct inode *inode)
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{
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struct super_block *sb = inode->i_sb;
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struct logfs_inode *li = logfs_inode(inode);
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inode->i_blocks = ULONG_MAX;
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if (li->li_used_bytes >> sb->s_blocksize_bits < ULONG_MAX)
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inode->i_blocks = ALIGN(li->li_used_bytes, 512) >> 9;
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}
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void logfs_set_blocks(struct inode *inode, u64 bytes)
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{
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struct logfs_inode *li = logfs_inode(inode);
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li->li_used_bytes = bytes;
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__logfs_set_blocks(inode);
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}
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static void prelock_page(struct super_block *sb, struct page *page, int lock)
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{
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struct logfs_super *super = logfs_super(sb);
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BUG_ON(!PageLocked(page));
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if (lock) {
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BUG_ON(PagePreLocked(page));
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SetPagePreLocked(page);
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} else {
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/* We are in GC path. */
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if (PagePreLocked(page))
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super->s_lock_count++;
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else
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SetPagePreLocked(page);
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}
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}
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static void preunlock_page(struct super_block *sb, struct page *page, int lock)
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{
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struct logfs_super *super = logfs_super(sb);
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BUG_ON(!PageLocked(page));
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if (lock)
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ClearPagePreLocked(page);
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else {
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/* We are in GC path. */
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BUG_ON(!PagePreLocked(page));
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if (super->s_lock_count)
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super->s_lock_count--;
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else
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ClearPagePreLocked(page);
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}
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}
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/*
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* Logfs is prone to an AB-BA deadlock where one task tries to acquire
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* s_write_mutex with a locked page and GC tries to get that page while holding
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* s_write_mutex.
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* To solve this issue logfs will ignore the page lock iff the page in question
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* is waiting for s_write_mutex. We annotate this fact by setting PG_pre_locked
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* in addition to PG_locked.
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*/
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void logfs_get_wblocks(struct super_block *sb, struct page *page, int lock)
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{
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struct logfs_super *super = logfs_super(sb);
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if (page)
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prelock_page(sb, page, lock);
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if (lock) {
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mutex_lock(&super->s_write_mutex);
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logfs_gc_pass(sb);
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/* FIXME: We also have to check for shadowed space
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* and mempool fill grade */
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}
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}
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void logfs_put_wblocks(struct super_block *sb, struct page *page, int lock)
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{
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struct logfs_super *super = logfs_super(sb);
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if (page)
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preunlock_page(sb, page, lock);
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/* Order matters - we must clear PG_pre_locked before releasing
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* s_write_mutex or we could race against another task. */
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if (lock)
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mutex_unlock(&super->s_write_mutex);
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}
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static struct page *logfs_get_read_page(struct inode *inode, u64 bix,
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level_t level)
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{
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return find_or_create_page(inode->i_mapping,
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logfs_pack_index(bix, level), GFP_NOFS);
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}
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static void logfs_put_read_page(struct page *page)
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{
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unlock_page(page);
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page_cache_release(page);
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}
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static void logfs_lock_write_page(struct page *page)
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{
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int loop = 0;
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while (unlikely(!trylock_page(page))) {
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if (loop++ > 0x1000) {
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/* Has been observed once so far... */
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printk(KERN_ERR "stack at %p\n", &loop);
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BUG();
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}
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if (PagePreLocked(page)) {
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/* Holder of page lock is waiting for us, it
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* is safe to use this page. */
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break;
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}
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/* Some other process has this page locked and has
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* nothing to do with us. Wait for it to finish.
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*/
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schedule();
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}
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BUG_ON(!PageLocked(page));
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}
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static struct page *logfs_get_write_page(struct inode *inode, u64 bix,
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level_t level)
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{
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struct address_space *mapping = inode->i_mapping;
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pgoff_t index = logfs_pack_index(bix, level);
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struct page *page;
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int err;
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repeat:
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page = find_get_page(mapping, index);
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if (!page) {
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page = __page_cache_alloc(GFP_NOFS);
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if (!page)
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return NULL;
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err = add_to_page_cache_lru(page, mapping, index, GFP_NOFS);
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if (unlikely(err)) {
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page_cache_release(page);
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if (err == -EEXIST)
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goto repeat;
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return NULL;
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}
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} else logfs_lock_write_page(page);
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BUG_ON(!PageLocked(page));
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return page;
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}
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static void logfs_unlock_write_page(struct page *page)
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{
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if (!PagePreLocked(page))
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unlock_page(page);
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}
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static void logfs_put_write_page(struct page *page)
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{
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logfs_unlock_write_page(page);
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page_cache_release(page);
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}
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static struct page *logfs_get_page(struct inode *inode, u64 bix, level_t level,
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int rw)
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{
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if (rw == READ)
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return logfs_get_read_page(inode, bix, level);
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else
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return logfs_get_write_page(inode, bix, level);
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}
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static void logfs_put_page(struct page *page, int rw)
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{
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if (rw == READ)
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logfs_put_read_page(page);
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else
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logfs_put_write_page(page);
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}
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static unsigned long __get_bits(u64 val, int skip, int no)
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{
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u64 ret = val;
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ret >>= skip * no;
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ret <<= 64 - no;
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ret >>= 64 - no;
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return ret;
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}
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static unsigned long get_bits(u64 val, level_t skip)
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{
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return __get_bits(val, (__force int)skip, LOGFS_BLOCK_BITS);
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}
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static inline void init_shadow_tree(struct super_block *sb,
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struct shadow_tree *tree)
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{
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struct logfs_super *super = logfs_super(sb);
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btree_init_mempool64(&tree->new, super->s_btree_pool);
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btree_init_mempool64(&tree->old, super->s_btree_pool);
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}
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static void indirect_write_block(struct logfs_block *block)
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{
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struct page *page;
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struct inode *inode;
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int ret;
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page = block->page;
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inode = page->mapping->host;
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logfs_lock_write_page(page);
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ret = logfs_write_buf(inode, page, 0);
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logfs_unlock_write_page(page);
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/*
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* This needs some rework. Unless you want your filesystem to run
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* completely synchronously (you don't), the filesystem will always
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* report writes as 'successful' before the actual work has been
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* done. The actual work gets done here and this is where any errors
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* will show up. And there isn't much we can do about it, really.
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*
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* Some attempts to fix the errors (move from bad blocks, retry io,...)
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* have already been done, so anything left should be either a broken
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* device or a bug somewhere in logfs itself. Being relatively new,
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* the odds currently favor a bug, so for now the line below isn't
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* entirely tasteles.
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*/
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BUG_ON(ret);
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}
|
|
|
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static void inode_write_block(struct logfs_block *block)
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{
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struct inode *inode;
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int ret;
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|
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inode = block->inode;
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if (inode->i_ino == LOGFS_INO_MASTER)
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logfs_write_anchor(inode->i_sb);
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else {
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ret = __logfs_write_inode(inode, NULL, 0);
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/* see indirect_write_block comment */
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BUG_ON(ret);
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}
|
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}
|
|
|
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/*
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|
* This silences a false, yet annoying gcc warning. I hate it when my editor
|
|
* jumps into bitops.h each time I recompile this file.
|
|
* TODO: Complain to gcc folks about this and upgrade compiler.
|
|
*/
|
|
static unsigned long fnb(const unsigned long *addr,
|
|
unsigned long size, unsigned long offset)
|
|
{
|
|
return find_next_bit(addr, size, offset);
|
|
}
|
|
|
|
static __be64 inode_val0(struct inode *inode)
|
|
{
|
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struct logfs_inode *li = logfs_inode(inode);
|
|
u64 val;
|
|
|
|
/*
|
|
* Explicit shifting generates good code, but must match the format
|
|
* of the structure. Add some paranoia just in case.
|
|
*/
|
|
BUILD_BUG_ON(offsetof(struct logfs_disk_inode, di_mode) != 0);
|
|
BUILD_BUG_ON(offsetof(struct logfs_disk_inode, di_height) != 2);
|
|
BUILD_BUG_ON(offsetof(struct logfs_disk_inode, di_flags) != 4);
|
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|
|
val = (u64)inode->i_mode << 48 |
|
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(u64)li->li_height << 40 |
|
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(u64)li->li_flags;
|
|
return cpu_to_be64(val);
|
|
}
|
|
|
|
static int inode_write_alias(struct super_block *sb,
|
|
struct logfs_block *block, write_alias_t *write_one_alias)
|
|
{
|
|
struct inode *inode = block->inode;
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
unsigned long pos;
|
|
u64 ino , bix;
|
|
__be64 val;
|
|
level_t level;
|
|
int err;
|
|
|
|
for (pos = 0; ; pos++) {
|
|
pos = fnb(block->alias_map, LOGFS_BLOCK_FACTOR, pos);
|
|
if (pos >= LOGFS_EMBEDDED_FIELDS + INODE_POINTER_OFS)
|
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return 0;
|
|
|
|
switch (pos) {
|
|
case INODE_HEIGHT_OFS:
|
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val = inode_val0(inode);
|
|
break;
|
|
case INODE_USED_OFS:
|
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val = cpu_to_be64(li->li_used_bytes);
|
|
break;
|
|
case INODE_SIZE_OFS:
|
|
val = cpu_to_be64(i_size_read(inode));
|
|
break;
|
|
case INODE_POINTER_OFS ... INODE_POINTER_OFS + LOGFS_EMBEDDED_FIELDS - 1:
|
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val = cpu_to_be64(li->li_data[pos - INODE_POINTER_OFS]);
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
ino = LOGFS_INO_MASTER;
|
|
bix = inode->i_ino;
|
|
level = LEVEL(0);
|
|
err = write_one_alias(sb, ino, bix, level, pos, val);
|
|
if (err)
|
|
return err;
|
|
}
|
|
}
|
|
|
|
static int indirect_write_alias(struct super_block *sb,
|
|
struct logfs_block *block, write_alias_t *write_one_alias)
|
|
{
|
|
unsigned long pos;
|
|
struct page *page = block->page;
|
|
u64 ino , bix;
|
|
__be64 *child, val;
|
|
level_t level;
|
|
int err;
|
|
|
|
for (pos = 0; ; pos++) {
|
|
pos = fnb(block->alias_map, LOGFS_BLOCK_FACTOR, pos);
|
|
if (pos >= LOGFS_BLOCK_FACTOR)
|
|
return 0;
|
|
|
|
ino = page->mapping->host->i_ino;
|
|
logfs_unpack_index(page->index, &bix, &level);
|
|
child = kmap_atomic(page, KM_USER0);
|
|
val = child[pos];
|
|
kunmap_atomic(child, KM_USER0);
|
|
err = write_one_alias(sb, ino, bix, level, pos, val);
|
|
if (err)
|
|
return err;
|
|
}
|
|
}
|
|
|
|
int logfs_write_obj_aliases_pagecache(struct super_block *sb)
|
|
{
|
|
struct logfs_super *super = logfs_super(sb);
|
|
struct logfs_block *block;
|
|
int err;
|
|
|
|
list_for_each_entry(block, &super->s_object_alias, alias_list) {
|
|
err = block->ops->write_alias(sb, block, write_alias_journal);
|
|
if (err)
|
|
return err;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void __free_block(struct super_block *sb, struct logfs_block *block)
|
|
{
|
|
BUG_ON(!list_empty(&block->item_list));
|
|
list_del(&block->alias_list);
|
|
mempool_free(block, logfs_super(sb)->s_block_pool);
|
|
}
|
|
|
|
static void inode_free_block(struct super_block *sb, struct logfs_block *block)
|
|
{
|
|
struct inode *inode = block->inode;
|
|
|
|
logfs_inode(inode)->li_block = NULL;
|
|
__free_block(sb, block);
|
|
}
|
|
|
|
static void indirect_free_block(struct super_block *sb,
|
|
struct logfs_block *block)
|
|
{
|
|
struct page *page = block->page;
|
|
|
|
if (PagePrivate(page)) {
|
|
ClearPagePrivate(page);
|
|
page_cache_release(page);
|
|
set_page_private(page, 0);
|
|
}
|
|
__free_block(sb, block);
|
|
}
|
|
|
|
|
|
static struct logfs_block_ops inode_block_ops = {
|
|
.write_block = inode_write_block,
|
|
.free_block = inode_free_block,
|
|
.write_alias = inode_write_alias,
|
|
};
|
|
|
|
struct logfs_block_ops indirect_block_ops = {
|
|
.write_block = indirect_write_block,
|
|
.free_block = indirect_free_block,
|
|
.write_alias = indirect_write_alias,
|
|
};
|
|
|
|
struct logfs_block *__alloc_block(struct super_block *sb,
|
|
u64 ino, u64 bix, level_t level)
|
|
{
|
|
struct logfs_super *super = logfs_super(sb);
|
|
struct logfs_block *block;
|
|
|
|
block = mempool_alloc(super->s_block_pool, GFP_NOFS);
|
|
memset(block, 0, sizeof(*block));
|
|
INIT_LIST_HEAD(&block->alias_list);
|
|
INIT_LIST_HEAD(&block->item_list);
|
|
block->sb = sb;
|
|
block->ino = ino;
|
|
block->bix = bix;
|
|
block->level = level;
|
|
return block;
|
|
}
|
|
|
|
static void alloc_inode_block(struct inode *inode)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
struct logfs_block *block;
|
|
|
|
if (li->li_block)
|
|
return;
|
|
|
|
block = __alloc_block(inode->i_sb, LOGFS_INO_MASTER, inode->i_ino, 0);
|
|
block->inode = inode;
|
|
li->li_block = block;
|
|
block->ops = &inode_block_ops;
|
|
}
|
|
|
|
void initialize_block_counters(struct page *page, struct logfs_block *block,
|
|
__be64 *array, int page_is_empty)
|
|
{
|
|
u64 ptr;
|
|
int i, start;
|
|
|
|
block->partial = 0;
|
|
block->full = 0;
|
|
start = 0;
|
|
if (page->index < first_indirect_block()) {
|
|
/* Counters are pointless on level 0 */
|
|
return;
|
|
}
|
|
if (page->index == first_indirect_block()) {
|
|
/* Skip unused pointers */
|
|
start = I0_BLOCKS;
|
|
block->full = I0_BLOCKS;
|
|
}
|
|
if (!page_is_empty) {
|
|
for (i = start; i < LOGFS_BLOCK_FACTOR; i++) {
|
|
ptr = be64_to_cpu(array[i]);
|
|
if (ptr)
|
|
block->partial++;
|
|
if (ptr & LOGFS_FULLY_POPULATED)
|
|
block->full++;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void alloc_data_block(struct inode *inode, struct page *page)
|
|
{
|
|
struct logfs_block *block;
|
|
u64 bix;
|
|
level_t level;
|
|
|
|
if (PagePrivate(page))
|
|
return;
|
|
|
|
logfs_unpack_index(page->index, &bix, &level);
|
|
block = __alloc_block(inode->i_sb, inode->i_ino, bix, level);
|
|
block->page = page;
|
|
|
|
SetPagePrivate(page);
|
|
page_cache_get(page);
|
|
set_page_private(page, (unsigned long) block);
|
|
|
|
block->ops = &indirect_block_ops;
|
|
}
|
|
|
|
static void alloc_indirect_block(struct inode *inode, struct page *page,
|
|
int page_is_empty)
|
|
{
|
|
struct logfs_block *block;
|
|
__be64 *array;
|
|
|
|
if (PagePrivate(page))
|
|
return;
|
|
|
|
alloc_data_block(inode, page);
|
|
|
|
block = logfs_block(page);
|
|
array = kmap_atomic(page, KM_USER0);
|
|
initialize_block_counters(page, block, array, page_is_empty);
|
|
kunmap_atomic(array, KM_USER0);
|
|
}
|
|
|
|
static void block_set_pointer(struct page *page, int index, u64 ptr)
|
|
{
|
|
struct logfs_block *block = logfs_block(page);
|
|
__be64 *array;
|
|
u64 oldptr;
|
|
|
|
BUG_ON(!block);
|
|
array = kmap_atomic(page, KM_USER0);
|
|
oldptr = be64_to_cpu(array[index]);
|
|
array[index] = cpu_to_be64(ptr);
|
|
kunmap_atomic(array, KM_USER0);
|
|
SetPageUptodate(page);
|
|
|
|
block->full += !!(ptr & LOGFS_FULLY_POPULATED)
|
|
- !!(oldptr & LOGFS_FULLY_POPULATED);
|
|
block->partial += !!ptr - !!oldptr;
|
|
}
|
|
|
|
static u64 block_get_pointer(struct page *page, int index)
|
|
{
|
|
__be64 *block;
|
|
u64 ptr;
|
|
|
|
block = kmap_atomic(page, KM_USER0);
|
|
ptr = be64_to_cpu(block[index]);
|
|
kunmap_atomic(block, KM_USER0);
|
|
return ptr;
|
|
}
|
|
|
|
static int logfs_read_empty(struct page *page)
|
|
{
|
|
zero_user_segment(page, 0, PAGE_CACHE_SIZE);
|
|
return 0;
|
|
}
|
|
|
|
static int logfs_read_direct(struct inode *inode, struct page *page)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
pgoff_t index = page->index;
|
|
u64 block;
|
|
|
|
block = li->li_data[index];
|
|
if (!block)
|
|
return logfs_read_empty(page);
|
|
|
|
return logfs_segment_read(inode, page, block, index, 0);
|
|
}
|
|
|
|
static int logfs_read_loop(struct inode *inode, struct page *page,
|
|
int rw_context)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
u64 bix, bofs = li->li_data[INDIRECT_INDEX];
|
|
level_t level, target_level;
|
|
int ret;
|
|
struct page *ipage;
|
|
|
|
logfs_unpack_index(page->index, &bix, &target_level);
|
|
if (!bofs)
|
|
return logfs_read_empty(page);
|
|
|
|
if (bix >= maxbix(li->li_height))
|
|
return logfs_read_empty(page);
|
|
|
|
for (level = LEVEL(li->li_height);
|
|
(__force u8)level > (__force u8)target_level;
|
|
level = SUBLEVEL(level)){
|
|
ipage = logfs_get_page(inode, bix, level, rw_context);
|
|
if (!ipage)
|
|
return -ENOMEM;
|
|
|
|
ret = logfs_segment_read(inode, ipage, bofs, bix, level);
|
|
if (ret) {
|
|
logfs_put_read_page(ipage);
|
|
return ret;
|
|
}
|
|
|
|
bofs = block_get_pointer(ipage, get_bits(bix, SUBLEVEL(level)));
|
|
logfs_put_page(ipage, rw_context);
|
|
if (!bofs)
|
|
return logfs_read_empty(page);
|
|
}
|
|
|
|
return logfs_segment_read(inode, page, bofs, bix, 0);
|
|
}
|
|
|
|
static int logfs_read_block(struct inode *inode, struct page *page,
|
|
int rw_context)
|
|
{
|
|
pgoff_t index = page->index;
|
|
|
|
if (index < I0_BLOCKS)
|
|
return logfs_read_direct(inode, page);
|
|
return logfs_read_loop(inode, page, rw_context);
|
|
}
|
|
|
|
static int logfs_exist_loop(struct inode *inode, u64 bix)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
u64 bofs = li->li_data[INDIRECT_INDEX];
|
|
level_t level;
|
|
int ret;
|
|
struct page *ipage;
|
|
|
|
if (!bofs)
|
|
return 0;
|
|
if (bix >= maxbix(li->li_height))
|
|
return 0;
|
|
|
|
for (level = LEVEL(li->li_height); level != 0; level = SUBLEVEL(level)) {
|
|
ipage = logfs_get_read_page(inode, bix, level);
|
|
if (!ipage)
|
|
return -ENOMEM;
|
|
|
|
ret = logfs_segment_read(inode, ipage, bofs, bix, level);
|
|
if (ret) {
|
|
logfs_put_read_page(ipage);
|
|
return ret;
|
|
}
|
|
|
|
bofs = block_get_pointer(ipage, get_bits(bix, SUBLEVEL(level)));
|
|
logfs_put_read_page(ipage);
|
|
if (!bofs)
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
int logfs_exist_block(struct inode *inode, u64 bix)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
|
|
if (bix < I0_BLOCKS)
|
|
return !!li->li_data[bix];
|
|
return logfs_exist_loop(inode, bix);
|
|
}
|
|
|
|
static u64 seek_holedata_direct(struct inode *inode, u64 bix, int data)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
|
|
for (; bix < I0_BLOCKS; bix++)
|
|
if (data ^ (li->li_data[bix] == 0))
|
|
return bix;
|
|
return I0_BLOCKS;
|
|
}
|
|
|
|
static u64 seek_holedata_loop(struct inode *inode, u64 bix, int data)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
__be64 *rblock;
|
|
u64 increment, bofs = li->li_data[INDIRECT_INDEX];
|
|
level_t level;
|
|
int ret, slot;
|
|
struct page *page;
|
|
|
|
BUG_ON(!bofs);
|
|
|
|
for (level = LEVEL(li->li_height); level != 0; level = SUBLEVEL(level)) {
|
|
increment = 1 << (LOGFS_BLOCK_BITS * ((__force u8)level-1));
|
|
page = logfs_get_read_page(inode, bix, level);
|
|
if (!page)
|
|
return bix;
|
|
|
|
ret = logfs_segment_read(inode, page, bofs, bix, level);
|
|
if (ret) {
|
|
logfs_put_read_page(page);
|
|
return bix;
|
|
}
|
|
|
|
slot = get_bits(bix, SUBLEVEL(level));
|
|
rblock = kmap_atomic(page, KM_USER0);
|
|
while (slot < LOGFS_BLOCK_FACTOR) {
|
|
if (data && (rblock[slot] != 0))
|
|
break;
|
|
if (!data && !(be64_to_cpu(rblock[slot]) & LOGFS_FULLY_POPULATED))
|
|
break;
|
|
slot++;
|
|
bix += increment;
|
|
bix &= ~(increment - 1);
|
|
}
|
|
if (slot >= LOGFS_BLOCK_FACTOR) {
|
|
kunmap_atomic(rblock, KM_USER0);
|
|
logfs_put_read_page(page);
|
|
return bix;
|
|
}
|
|
bofs = be64_to_cpu(rblock[slot]);
|
|
kunmap_atomic(rblock, KM_USER0);
|
|
logfs_put_read_page(page);
|
|
if (!bofs) {
|
|
BUG_ON(data);
|
|
return bix;
|
|
}
|
|
}
|
|
return bix;
|
|
}
|
|
|
|
/**
|
|
* logfs_seek_hole - find next hole starting at a given block index
|
|
* @inode: inode to search in
|
|
* @bix: block index to start searching
|
|
*
|
|
* Returns next hole. If the file doesn't contain any further holes, the
|
|
* block address next to eof is returned instead.
|
|
*/
|
|
u64 logfs_seek_hole(struct inode *inode, u64 bix)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
|
|
if (bix < I0_BLOCKS) {
|
|
bix = seek_holedata_direct(inode, bix, 0);
|
|
if (bix < I0_BLOCKS)
|
|
return bix;
|
|
}
|
|
|
|
if (!li->li_data[INDIRECT_INDEX])
|
|
return bix;
|
|
else if (li->li_data[INDIRECT_INDEX] & LOGFS_FULLY_POPULATED)
|
|
bix = maxbix(li->li_height);
|
|
else if (bix >= maxbix(li->li_height))
|
|
return bix;
|
|
else {
|
|
bix = seek_holedata_loop(inode, bix, 0);
|
|
if (bix < maxbix(li->li_height))
|
|
return bix;
|
|
/* Should not happen anymore. But if some port writes semi-
|
|
* corrupt images (as this one used to) we might run into it.
|
|
*/
|
|
WARN_ON_ONCE(bix == maxbix(li->li_height));
|
|
}
|
|
|
|
return bix;
|
|
}
|
|
|
|
static u64 __logfs_seek_data(struct inode *inode, u64 bix)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
|
|
if (bix < I0_BLOCKS) {
|
|
bix = seek_holedata_direct(inode, bix, 1);
|
|
if (bix < I0_BLOCKS)
|
|
return bix;
|
|
}
|
|
|
|
if (bix < maxbix(li->li_height)) {
|
|
if (!li->li_data[INDIRECT_INDEX])
|
|
bix = maxbix(li->li_height);
|
|
else
|
|
return seek_holedata_loop(inode, bix, 1);
|
|
}
|
|
|
|
return bix;
|
|
}
|
|
|
|
/**
|
|
* logfs_seek_data - find next data block after a given block index
|
|
* @inode: inode to search in
|
|
* @bix: block index to start searching
|
|
*
|
|
* Returns next data block. If the file doesn't contain any further data
|
|
* blocks, the last block in the file is returned instead.
|
|
*/
|
|
u64 logfs_seek_data(struct inode *inode, u64 bix)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
u64 ret, end;
|
|
|
|
ret = __logfs_seek_data(inode, bix);
|
|
end = i_size_read(inode) >> sb->s_blocksize_bits;
|
|
if (ret >= end)
|
|
ret = max(bix, end);
|
|
return ret;
|
|
}
|
|
|
|
static int logfs_is_valid_direct(struct logfs_inode *li, u64 bix, u64 ofs)
|
|
{
|
|
return pure_ofs(li->li_data[bix]) == ofs;
|
|
}
|
|
|
|
static int __logfs_is_valid_loop(struct inode *inode, u64 bix,
|
|
u64 ofs, u64 bofs)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
level_t level;
|
|
int ret;
|
|
struct page *page;
|
|
|
|
for (level = LEVEL(li->li_height); level != 0; level = SUBLEVEL(level)){
|
|
page = logfs_get_write_page(inode, bix, level);
|
|
BUG_ON(!page);
|
|
|
|
ret = logfs_segment_read(inode, page, bofs, bix, level);
|
|
if (ret) {
|
|
logfs_put_write_page(page);
|
|
return 0;
|
|
}
|
|
|
|
bofs = block_get_pointer(page, get_bits(bix, SUBLEVEL(level)));
|
|
logfs_put_write_page(page);
|
|
if (!bofs)
|
|
return 0;
|
|
|
|
if (pure_ofs(bofs) == ofs)
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int logfs_is_valid_loop(struct inode *inode, u64 bix, u64 ofs)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
u64 bofs = li->li_data[INDIRECT_INDEX];
|
|
|
|
if (!bofs)
|
|
return 0;
|
|
|
|
if (bix >= maxbix(li->li_height))
|
|
return 0;
|
|
|
|
if (pure_ofs(bofs) == ofs)
|
|
return 1;
|
|
|
|
return __logfs_is_valid_loop(inode, bix, ofs, bofs);
|
|
}
|
|
|
|
static int __logfs_is_valid_block(struct inode *inode, u64 bix, u64 ofs)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
|
|
if ((inode->i_nlink == 0) && atomic_read(&inode->i_count) == 1)
|
|
return 0;
|
|
|
|
if (bix < I0_BLOCKS)
|
|
return logfs_is_valid_direct(li, bix, ofs);
|
|
return logfs_is_valid_loop(inode, bix, ofs);
|
|
}
|
|
|
|
/**
|
|
* logfs_is_valid_block - check whether this block is still valid
|
|
*
|
|
* @sb - superblock
|
|
* @ofs - block physical offset
|
|
* @ino - block inode number
|
|
* @bix - block index
|
|
* @level - block level
|
|
*
|
|
* Returns 0 if the block is invalid, 1 if it is valid and 2 if it will
|
|
* become invalid once the journal is written.
|
|
*/
|
|
int logfs_is_valid_block(struct super_block *sb, u64 ofs, u64 ino, u64 bix,
|
|
gc_level_t gc_level)
|
|
{
|
|
struct logfs_super *super = logfs_super(sb);
|
|
struct inode *inode;
|
|
int ret, cookie;
|
|
|
|
/* Umount closes a segment with free blocks remaining. Those
|
|
* blocks are by definition invalid. */
|
|
if (ino == -1)
|
|
return 0;
|
|
|
|
LOGFS_BUG_ON((u64)(u_long)ino != ino, sb);
|
|
|
|
inode = logfs_safe_iget(sb, ino, &cookie);
|
|
if (IS_ERR(inode))
|
|
goto invalid;
|
|
|
|
ret = __logfs_is_valid_block(inode, bix, ofs);
|
|
logfs_safe_iput(inode, cookie);
|
|
if (ret)
|
|
return ret;
|
|
|
|
invalid:
|
|
/* Block is nominally invalid, but may still sit in the shadow tree,
|
|
* waiting for a journal commit.
|
|
*/
|
|
if (btree_lookup64(&super->s_shadow_tree.old, ofs))
|
|
return 2;
|
|
return 0;
|
|
}
|
|
|
|
int logfs_readpage_nolock(struct page *page)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
int ret = -EIO;
|
|
|
|
ret = logfs_read_block(inode, page, READ);
|
|
|
|
if (ret) {
|
|
ClearPageUptodate(page);
|
|
SetPageError(page);
|
|
} else {
|
|
SetPageUptodate(page);
|
|
ClearPageError(page);
|
|
}
|
|
flush_dcache_page(page);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int logfs_reserve_bytes(struct inode *inode, int bytes)
|
|
{
|
|
struct logfs_super *super = logfs_super(inode->i_sb);
|
|
u64 available = super->s_free_bytes + super->s_dirty_free_bytes
|
|
- super->s_dirty_used_bytes - super->s_dirty_pages;
|
|
|
|
if (!bytes)
|
|
return 0;
|
|
|
|
if (available < bytes)
|
|
return -ENOSPC;
|
|
|
|
if (available < bytes + super->s_root_reserve &&
|
|
!capable(CAP_SYS_RESOURCE))
|
|
return -ENOSPC;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int get_page_reserve(struct inode *inode, struct page *page)
|
|
{
|
|
struct logfs_super *super = logfs_super(inode->i_sb);
|
|
struct logfs_block *block = logfs_block(page);
|
|
int ret;
|
|
|
|
if (block && block->reserved_bytes)
|
|
return 0;
|
|
|
|
logfs_get_wblocks(inode->i_sb, page, WF_LOCK);
|
|
while ((ret = logfs_reserve_bytes(inode, 6 * LOGFS_MAX_OBJECTSIZE)) &&
|
|
!list_empty(&super->s_writeback_list)) {
|
|
block = list_entry(super->s_writeback_list.next,
|
|
struct logfs_block, alias_list);
|
|
block->ops->write_block(block);
|
|
}
|
|
if (!ret) {
|
|
alloc_data_block(inode, page);
|
|
block = logfs_block(page);
|
|
block->reserved_bytes += 6 * LOGFS_MAX_OBJECTSIZE;
|
|
super->s_dirty_pages += 6 * LOGFS_MAX_OBJECTSIZE;
|
|
list_move_tail(&block->alias_list, &super->s_writeback_list);
|
|
}
|
|
logfs_put_wblocks(inode->i_sb, page, WF_LOCK);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* We are protected by write lock. Push victims up to superblock level
|
|
* and release transaction when appropriate.
|
|
*/
|
|
/* FIXME: This is currently called from the wrong spots. */
|
|
static void logfs_handle_transaction(struct inode *inode,
|
|
struct logfs_transaction *ta)
|
|
{
|
|
struct logfs_super *super = logfs_super(inode->i_sb);
|
|
|
|
if (!ta)
|
|
return;
|
|
logfs_inode(inode)->li_block->ta = NULL;
|
|
|
|
if (inode->i_ino != LOGFS_INO_MASTER) {
|
|
BUG(); /* FIXME: Yes, this needs more thought */
|
|
/* just remember the transaction until inode is written */
|
|
//BUG_ON(logfs_inode(inode)->li_transaction);
|
|
//logfs_inode(inode)->li_transaction = ta;
|
|
return;
|
|
}
|
|
|
|
switch (ta->state) {
|
|
case CREATE_1: /* fall through */
|
|
case UNLINK_1:
|
|
BUG_ON(super->s_victim_ino);
|
|
super->s_victim_ino = ta->ino;
|
|
break;
|
|
case CREATE_2: /* fall through */
|
|
case UNLINK_2:
|
|
BUG_ON(super->s_victim_ino != ta->ino);
|
|
super->s_victim_ino = 0;
|
|
/* transaction ends here - free it */
|
|
kfree(ta);
|
|
break;
|
|
case CROSS_RENAME_1:
|
|
BUG_ON(super->s_rename_dir);
|
|
BUG_ON(super->s_rename_pos);
|
|
super->s_rename_dir = ta->dir;
|
|
super->s_rename_pos = ta->pos;
|
|
break;
|
|
case CROSS_RENAME_2:
|
|
BUG_ON(super->s_rename_dir != ta->dir);
|
|
BUG_ON(super->s_rename_pos != ta->pos);
|
|
super->s_rename_dir = 0;
|
|
super->s_rename_pos = 0;
|
|
kfree(ta);
|
|
break;
|
|
case TARGET_RENAME_1:
|
|
BUG_ON(super->s_rename_dir);
|
|
BUG_ON(super->s_rename_pos);
|
|
BUG_ON(super->s_victim_ino);
|
|
super->s_rename_dir = ta->dir;
|
|
super->s_rename_pos = ta->pos;
|
|
super->s_victim_ino = ta->ino;
|
|
break;
|
|
case TARGET_RENAME_2:
|
|
BUG_ON(super->s_rename_dir != ta->dir);
|
|
BUG_ON(super->s_rename_pos != ta->pos);
|
|
BUG_ON(super->s_victim_ino != ta->ino);
|
|
super->s_rename_dir = 0;
|
|
super->s_rename_pos = 0;
|
|
break;
|
|
case TARGET_RENAME_3:
|
|
BUG_ON(super->s_rename_dir);
|
|
BUG_ON(super->s_rename_pos);
|
|
BUG_ON(super->s_victim_ino != ta->ino);
|
|
super->s_victim_ino = 0;
|
|
kfree(ta);
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Not strictly a reservation, but rather a check that we still have enough
|
|
* space to satisfy the write.
|
|
*/
|
|
static int logfs_reserve_blocks(struct inode *inode, int blocks)
|
|
{
|
|
return logfs_reserve_bytes(inode, blocks * LOGFS_MAX_OBJECTSIZE);
|
|
}
|
|
|
|
struct write_control {
|
|
u64 ofs;
|
|
long flags;
|
|
};
|
|
|
|
static struct logfs_shadow *alloc_shadow(struct inode *inode, u64 bix,
|
|
level_t level, u64 old_ofs)
|
|
{
|
|
struct logfs_super *super = logfs_super(inode->i_sb);
|
|
struct logfs_shadow *shadow;
|
|
|
|
shadow = mempool_alloc(super->s_shadow_pool, GFP_NOFS);
|
|
memset(shadow, 0, sizeof(*shadow));
|
|
shadow->ino = inode->i_ino;
|
|
shadow->bix = bix;
|
|
shadow->gc_level = expand_level(inode->i_ino, level);
|
|
shadow->old_ofs = old_ofs & ~LOGFS_FULLY_POPULATED;
|
|
return shadow;
|
|
}
|
|
|
|
static void free_shadow(struct inode *inode, struct logfs_shadow *shadow)
|
|
{
|
|
struct logfs_super *super = logfs_super(inode->i_sb);
|
|
|
|
mempool_free(shadow, super->s_shadow_pool);
|
|
}
|
|
|
|
static void mark_segment(struct shadow_tree *tree, u32 segno)
|
|
{
|
|
int err;
|
|
|
|
if (!btree_lookup32(&tree->segment_map, segno)) {
|
|
err = btree_insert32(&tree->segment_map, segno, (void *)1,
|
|
GFP_NOFS);
|
|
BUG_ON(err);
|
|
tree->no_shadowed_segments++;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* fill_shadow_tree - Propagate shadow tree changes due to a write
|
|
* @inode: Inode owning the page
|
|
* @page: Struct page that was written
|
|
* @shadow: Shadow for the current write
|
|
*
|
|
* Writes in logfs can result in two semi-valid objects. The old object
|
|
* is still valid as long as it can be reached by following pointers on
|
|
* the medium. Only when writes propagate all the way up to the journal
|
|
* has the new object safely replaced the old one.
|
|
*
|
|
* To handle this problem, a struct logfs_shadow is used to represent
|
|
* every single write. It is attached to the indirect block, which is
|
|
* marked dirty. When the indirect block is written, its shadows are
|
|
* handed up to the next indirect block (or inode). Untimately they
|
|
* will reach the master inode and be freed upon journal commit.
|
|
*
|
|
* This function handles a single step in the propagation. It adds the
|
|
* shadow for the current write to the tree, along with any shadows in
|
|
* the page's tree, in case it was an indirect block. If a page is
|
|
* written, the inode parameter is left NULL, if an inode is written,
|
|
* the page parameter is left NULL.
|
|
*/
|
|
static void fill_shadow_tree(struct inode *inode, struct page *page,
|
|
struct logfs_shadow *shadow)
|
|
{
|
|
struct logfs_super *super = logfs_super(inode->i_sb);
|
|
struct logfs_block *block = logfs_block(page);
|
|
struct shadow_tree *tree = &super->s_shadow_tree;
|
|
|
|
if (PagePrivate(page)) {
|
|
if (block->alias_map)
|
|
super->s_no_object_aliases -= bitmap_weight(
|
|
block->alias_map, LOGFS_BLOCK_FACTOR);
|
|
logfs_handle_transaction(inode, block->ta);
|
|
block->ops->free_block(inode->i_sb, block);
|
|
}
|
|
if (shadow) {
|
|
if (shadow->old_ofs)
|
|
btree_insert64(&tree->old, shadow->old_ofs, shadow,
|
|
GFP_NOFS);
|
|
else
|
|
btree_insert64(&tree->new, shadow->new_ofs, shadow,
|
|
GFP_NOFS);
|
|
|
|
super->s_dirty_used_bytes += shadow->new_len;
|
|
super->s_dirty_free_bytes += shadow->old_len;
|
|
mark_segment(tree, shadow->old_ofs >> super->s_segshift);
|
|
mark_segment(tree, shadow->new_ofs >> super->s_segshift);
|
|
}
|
|
}
|
|
|
|
static void logfs_set_alias(struct super_block *sb, struct logfs_block *block,
|
|
long child_no)
|
|
{
|
|
struct logfs_super *super = logfs_super(sb);
|
|
|
|
if (block->inode && block->inode->i_ino == LOGFS_INO_MASTER) {
|
|
/* Aliases in the master inode are pointless. */
|
|
return;
|
|
}
|
|
|
|
if (!test_bit(child_no, block->alias_map)) {
|
|
set_bit(child_no, block->alias_map);
|
|
super->s_no_object_aliases++;
|
|
}
|
|
list_move_tail(&block->alias_list, &super->s_object_alias);
|
|
}
|
|
|
|
/*
|
|
* Object aliases can and often do change the size and occupied space of a
|
|
* file. So not only do we have to change the pointers, we also have to
|
|
* change inode->i_size and li->li_used_bytes. Which is done by setting
|
|
* another two object aliases for the inode itself.
|
|
*/
|
|
static void set_iused(struct inode *inode, struct logfs_shadow *shadow)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
|
|
if (shadow->new_len == shadow->old_len)
|
|
return;
|
|
|
|
alloc_inode_block(inode);
|
|
li->li_used_bytes += shadow->new_len - shadow->old_len;
|
|
__logfs_set_blocks(inode);
|
|
logfs_set_alias(inode->i_sb, li->li_block, INODE_USED_OFS);
|
|
logfs_set_alias(inode->i_sb, li->li_block, INODE_SIZE_OFS);
|
|
}
|
|
|
|
static int logfs_write_i0(struct inode *inode, struct page *page,
|
|
struct write_control *wc)
|
|
{
|
|
struct logfs_shadow *shadow;
|
|
u64 bix;
|
|
level_t level;
|
|
int full, err = 0;
|
|
|
|
logfs_unpack_index(page->index, &bix, &level);
|
|
if (wc->ofs == 0)
|
|
if (logfs_reserve_blocks(inode, 1))
|
|
return -ENOSPC;
|
|
|
|
shadow = alloc_shadow(inode, bix, level, wc->ofs);
|
|
if (wc->flags & WF_WRITE)
|
|
err = logfs_segment_write(inode, page, shadow);
|
|
if (wc->flags & WF_DELETE)
|
|
logfs_segment_delete(inode, shadow);
|
|
if (err) {
|
|
free_shadow(inode, shadow);
|
|
return err;
|
|
}
|
|
|
|
set_iused(inode, shadow);
|
|
full = 1;
|
|
if (level != 0) {
|
|
alloc_indirect_block(inode, page, 0);
|
|
full = logfs_block(page)->full == LOGFS_BLOCK_FACTOR;
|
|
}
|
|
fill_shadow_tree(inode, page, shadow);
|
|
wc->ofs = shadow->new_ofs;
|
|
if (wc->ofs && full)
|
|
wc->ofs |= LOGFS_FULLY_POPULATED;
|
|
return 0;
|
|
}
|
|
|
|
static int logfs_write_direct(struct inode *inode, struct page *page,
|
|
long flags)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
struct write_control wc = {
|
|
.ofs = li->li_data[page->index],
|
|
.flags = flags,
|
|
};
|
|
int err;
|
|
|
|
alloc_inode_block(inode);
|
|
|
|
err = logfs_write_i0(inode, page, &wc);
|
|
if (err)
|
|
return err;
|
|
|
|
li->li_data[page->index] = wc.ofs;
|
|
logfs_set_alias(inode->i_sb, li->li_block,
|
|
page->index + INODE_POINTER_OFS);
|
|
return 0;
|
|
}
|
|
|
|
static int ptr_change(u64 ofs, struct page *page)
|
|
{
|
|
struct logfs_block *block = logfs_block(page);
|
|
int empty0, empty1, full0, full1;
|
|
|
|
empty0 = ofs == 0;
|
|
empty1 = block->partial == 0;
|
|
if (empty0 != empty1)
|
|
return 1;
|
|
|
|
/* The !! is necessary to shrink result to int */
|
|
full0 = !!(ofs & LOGFS_FULLY_POPULATED);
|
|
full1 = block->full == LOGFS_BLOCK_FACTOR;
|
|
if (full0 != full1)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static int __logfs_write_rec(struct inode *inode, struct page *page,
|
|
struct write_control *this_wc,
|
|
pgoff_t bix, level_t target_level, level_t level)
|
|
{
|
|
int ret, page_empty = 0;
|
|
int child_no = get_bits(bix, SUBLEVEL(level));
|
|
struct page *ipage;
|
|
struct write_control child_wc = {
|
|
.flags = this_wc->flags,
|
|
};
|
|
|
|
ipage = logfs_get_write_page(inode, bix, level);
|
|
if (!ipage)
|
|
return -ENOMEM;
|
|
|
|
if (this_wc->ofs) {
|
|
ret = logfs_segment_read(inode, ipage, this_wc->ofs, bix, level);
|
|
if (ret)
|
|
goto out;
|
|
} else if (!PageUptodate(ipage)) {
|
|
page_empty = 1;
|
|
logfs_read_empty(ipage);
|
|
}
|
|
|
|
child_wc.ofs = block_get_pointer(ipage, child_no);
|
|
|
|
if ((__force u8)level-1 > (__force u8)target_level)
|
|
ret = __logfs_write_rec(inode, page, &child_wc, bix,
|
|
target_level, SUBLEVEL(level));
|
|
else
|
|
ret = logfs_write_i0(inode, page, &child_wc);
|
|
|
|
if (ret)
|
|
goto out;
|
|
|
|
alloc_indirect_block(inode, ipage, page_empty);
|
|
block_set_pointer(ipage, child_no, child_wc.ofs);
|
|
/* FIXME: first condition seems superfluous */
|
|
if (child_wc.ofs || logfs_block(ipage)->partial)
|
|
this_wc->flags |= WF_WRITE;
|
|
/* the condition on this_wc->ofs ensures that we won't consume extra
|
|
* space for indirect blocks in the future, which we cannot reserve */
|
|
if (!this_wc->ofs || ptr_change(this_wc->ofs, ipage))
|
|
ret = logfs_write_i0(inode, ipage, this_wc);
|
|
else
|
|
logfs_set_alias(inode->i_sb, logfs_block(ipage), child_no);
|
|
out:
|
|
logfs_put_write_page(ipage);
|
|
return ret;
|
|
}
|
|
|
|
static int logfs_write_rec(struct inode *inode, struct page *page,
|
|
pgoff_t bix, level_t target_level, long flags)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
struct write_control wc = {
|
|
.ofs = li->li_data[INDIRECT_INDEX],
|
|
.flags = flags,
|
|
};
|
|
int ret;
|
|
|
|
alloc_inode_block(inode);
|
|
|
|
if (li->li_height > (__force u8)target_level)
|
|
ret = __logfs_write_rec(inode, page, &wc, bix, target_level,
|
|
LEVEL(li->li_height));
|
|
else
|
|
ret = logfs_write_i0(inode, page, &wc);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (li->li_data[INDIRECT_INDEX] != wc.ofs) {
|
|
li->li_data[INDIRECT_INDEX] = wc.ofs;
|
|
logfs_set_alias(inode->i_sb, li->li_block,
|
|
INDIRECT_INDEX + INODE_POINTER_OFS);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
void logfs_add_transaction(struct inode *inode, struct logfs_transaction *ta)
|
|
{
|
|
alloc_inode_block(inode);
|
|
logfs_inode(inode)->li_block->ta = ta;
|
|
}
|
|
|
|
void logfs_del_transaction(struct inode *inode, struct logfs_transaction *ta)
|
|
{
|
|
struct logfs_block *block = logfs_inode(inode)->li_block;
|
|
|
|
if (block && block->ta)
|
|
block->ta = NULL;
|
|
}
|
|
|
|
static int grow_inode(struct inode *inode, u64 bix, level_t level)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
u8 height = (__force u8)level;
|
|
struct page *page;
|
|
struct write_control wc = {
|
|
.flags = WF_WRITE,
|
|
};
|
|
int err;
|
|
|
|
BUG_ON(height > 5 || li->li_height > 5);
|
|
while (height > li->li_height || bix >= maxbix(li->li_height)) {
|
|
page = logfs_get_write_page(inode, I0_BLOCKS + 1,
|
|
LEVEL(li->li_height + 1));
|
|
if (!page)
|
|
return -ENOMEM;
|
|
logfs_read_empty(page);
|
|
alloc_indirect_block(inode, page, 1);
|
|
block_set_pointer(page, 0, li->li_data[INDIRECT_INDEX]);
|
|
err = logfs_write_i0(inode, page, &wc);
|
|
logfs_put_write_page(page);
|
|
if (err)
|
|
return err;
|
|
li->li_data[INDIRECT_INDEX] = wc.ofs;
|
|
wc.ofs = 0;
|
|
li->li_height++;
|
|
logfs_set_alias(inode->i_sb, li->li_block, INODE_HEIGHT_OFS);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int __logfs_write_buf(struct inode *inode, struct page *page, long flags)
|
|
{
|
|
struct logfs_super *super = logfs_super(inode->i_sb);
|
|
pgoff_t index = page->index;
|
|
u64 bix;
|
|
level_t level;
|
|
int err;
|
|
|
|
flags |= WF_WRITE | WF_DELETE;
|
|
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
|
|
|
|
logfs_unpack_index(index, &bix, &level);
|
|
if (logfs_block(page) && logfs_block(page)->reserved_bytes)
|
|
super->s_dirty_pages -= logfs_block(page)->reserved_bytes;
|
|
|
|
if (index < I0_BLOCKS)
|
|
return logfs_write_direct(inode, page, flags);
|
|
|
|
bix = adjust_bix(bix, level);
|
|
err = grow_inode(inode, bix, level);
|
|
if (err)
|
|
return err;
|
|
return logfs_write_rec(inode, page, bix, level, flags);
|
|
}
|
|
|
|
int logfs_write_buf(struct inode *inode, struct page *page, long flags)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
int ret;
|
|
|
|
logfs_get_wblocks(sb, page, flags & WF_LOCK);
|
|
ret = __logfs_write_buf(inode, page, flags);
|
|
logfs_put_wblocks(sb, page, flags & WF_LOCK);
|
|
return ret;
|
|
}
|
|
|
|
static int __logfs_delete(struct inode *inode, struct page *page)
|
|
{
|
|
long flags = WF_DELETE;
|
|
int err;
|
|
|
|
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
|
|
|
|
if (page->index < I0_BLOCKS)
|
|
return logfs_write_direct(inode, page, flags);
|
|
err = grow_inode(inode, page->index, 0);
|
|
if (err)
|
|
return err;
|
|
return logfs_write_rec(inode, page, page->index, 0, flags);
|
|
}
|
|
|
|
int logfs_delete(struct inode *inode, pgoff_t index,
|
|
struct shadow_tree *shadow_tree)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
struct page *page;
|
|
int ret;
|
|
|
|
page = logfs_get_read_page(inode, index, 0);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
logfs_get_wblocks(sb, page, 1);
|
|
ret = __logfs_delete(inode, page);
|
|
logfs_put_wblocks(sb, page, 1);
|
|
|
|
logfs_put_read_page(page);
|
|
|
|
return ret;
|
|
}
|
|
|
|
int logfs_rewrite_block(struct inode *inode, u64 bix, u64 ofs,
|
|
gc_level_t gc_level, long flags)
|
|
{
|
|
level_t level = shrink_level(gc_level);
|
|
struct page *page;
|
|
int err;
|
|
|
|
page = logfs_get_write_page(inode, bix, level);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
err = logfs_segment_read(inode, page, ofs, bix, level);
|
|
if (!err) {
|
|
if (level != 0)
|
|
alloc_indirect_block(inode, page, 0);
|
|
err = logfs_write_buf(inode, page, flags);
|
|
if (!err && shrink_level(gc_level) == 0) {
|
|
/* Rewrite cannot mark the inode dirty but has to
|
|
* write it immediately.
|
|
* Q: Can't we just create an alias for the inode
|
|
* instead? And if not, why not?
|
|
*/
|
|
if (inode->i_ino == LOGFS_INO_MASTER)
|
|
logfs_write_anchor(inode->i_sb);
|
|
else {
|
|
err = __logfs_write_inode(inode, page, flags);
|
|
}
|
|
}
|
|
}
|
|
logfs_put_write_page(page);
|
|
return err;
|
|
}
|
|
|
|
static int truncate_data_block(struct inode *inode, struct page *page,
|
|
u64 ofs, struct logfs_shadow *shadow, u64 size)
|
|
{
|
|
loff_t pageofs = page->index << inode->i_sb->s_blocksize_bits;
|
|
u64 bix;
|
|
level_t level;
|
|
int err;
|
|
|
|
/* Does truncation happen within this page? */
|
|
if (size <= pageofs || size - pageofs >= PAGE_SIZE)
|
|
return 0;
|
|
|
|
logfs_unpack_index(page->index, &bix, &level);
|
|
BUG_ON(level != 0);
|
|
|
|
err = logfs_segment_read(inode, page, ofs, bix, level);
|
|
if (err)
|
|
return err;
|
|
|
|
zero_user_segment(page, size - pageofs, PAGE_CACHE_SIZE);
|
|
return logfs_segment_write(inode, page, shadow);
|
|
}
|
|
|
|
static int logfs_truncate_i0(struct inode *inode, struct page *page,
|
|
struct write_control *wc, u64 size)
|
|
{
|
|
struct logfs_shadow *shadow;
|
|
u64 bix;
|
|
level_t level;
|
|
int err = 0;
|
|
|
|
logfs_unpack_index(page->index, &bix, &level);
|
|
BUG_ON(level != 0);
|
|
shadow = alloc_shadow(inode, bix, level, wc->ofs);
|
|
|
|
err = truncate_data_block(inode, page, wc->ofs, shadow, size);
|
|
if (err) {
|
|
free_shadow(inode, shadow);
|
|
return err;
|
|
}
|
|
|
|
logfs_segment_delete(inode, shadow);
|
|
set_iused(inode, shadow);
|
|
fill_shadow_tree(inode, page, shadow);
|
|
wc->ofs = shadow->new_ofs;
|
|
return 0;
|
|
}
|
|
|
|
static int logfs_truncate_direct(struct inode *inode, u64 size)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
struct write_control wc;
|
|
struct page *page;
|
|
int e;
|
|
int err;
|
|
|
|
alloc_inode_block(inode);
|
|
|
|
for (e = I0_BLOCKS - 1; e >= 0; e--) {
|
|
if (size > (e+1) * LOGFS_BLOCKSIZE)
|
|
break;
|
|
|
|
wc.ofs = li->li_data[e];
|
|
if (!wc.ofs)
|
|
continue;
|
|
|
|
page = logfs_get_write_page(inode, e, 0);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
err = logfs_segment_read(inode, page, wc.ofs, e, 0);
|
|
if (err) {
|
|
logfs_put_write_page(page);
|
|
return err;
|
|
}
|
|
err = logfs_truncate_i0(inode, page, &wc, size);
|
|
logfs_put_write_page(page);
|
|
if (err)
|
|
return err;
|
|
|
|
li->li_data[e] = wc.ofs;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* FIXME: these need to become per-sb once we support different blocksizes */
|
|
static u64 __logfs_step[] = {
|
|
1,
|
|
I1_BLOCKS,
|
|
I2_BLOCKS,
|
|
I3_BLOCKS,
|
|
};
|
|
|
|
static u64 __logfs_start_index[] = {
|
|
I0_BLOCKS,
|
|
I1_BLOCKS,
|
|
I2_BLOCKS,
|
|
I3_BLOCKS
|
|
};
|
|
|
|
static inline u64 logfs_step(level_t level)
|
|
{
|
|
return __logfs_step[(__force u8)level];
|
|
}
|
|
|
|
static inline u64 logfs_factor(u8 level)
|
|
{
|
|
return __logfs_step[level] * LOGFS_BLOCKSIZE;
|
|
}
|
|
|
|
static inline u64 logfs_start_index(level_t level)
|
|
{
|
|
return __logfs_start_index[(__force u8)level];
|
|
}
|
|
|
|
static void logfs_unpack_raw_index(pgoff_t index, u64 *bix, level_t *level)
|
|
{
|
|
logfs_unpack_index(index, bix, level);
|
|
if (*bix <= logfs_start_index(SUBLEVEL(*level)))
|
|
*bix = 0;
|
|
}
|
|
|
|
static int __logfs_truncate_rec(struct inode *inode, struct page *ipage,
|
|
struct write_control *this_wc, u64 size)
|
|
{
|
|
int truncate_happened = 0;
|
|
int e, err = 0;
|
|
u64 bix, child_bix, next_bix;
|
|
level_t level;
|
|
struct page *page;
|
|
struct write_control child_wc = { /* FIXME: flags */ };
|
|
|
|
logfs_unpack_raw_index(ipage->index, &bix, &level);
|
|
err = logfs_segment_read(inode, ipage, this_wc->ofs, bix, level);
|
|
if (err)
|
|
return err;
|
|
|
|
for (e = LOGFS_BLOCK_FACTOR - 1; e >= 0; e--) {
|
|
child_bix = bix + e * logfs_step(SUBLEVEL(level));
|
|
next_bix = child_bix + logfs_step(SUBLEVEL(level));
|
|
if (size > next_bix * LOGFS_BLOCKSIZE)
|
|
break;
|
|
|
|
child_wc.ofs = pure_ofs(block_get_pointer(ipage, e));
|
|
if (!child_wc.ofs)
|
|
continue;
|
|
|
|
page = logfs_get_write_page(inode, child_bix, SUBLEVEL(level));
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
if ((__force u8)level > 1)
|
|
err = __logfs_truncate_rec(inode, page, &child_wc, size);
|
|
else
|
|
err = logfs_truncate_i0(inode, page, &child_wc, size);
|
|
logfs_put_write_page(page);
|
|
if (err)
|
|
return err;
|
|
|
|
truncate_happened = 1;
|
|
alloc_indirect_block(inode, ipage, 0);
|
|
block_set_pointer(ipage, e, child_wc.ofs);
|
|
}
|
|
|
|
if (!truncate_happened) {
|
|
printk("ineffectual truncate (%lx, %lx, %llx)\n", inode->i_ino, ipage->index, size);
|
|
return 0;
|
|
}
|
|
|
|
this_wc->flags = WF_DELETE;
|
|
if (logfs_block(ipage)->partial)
|
|
this_wc->flags |= WF_WRITE;
|
|
|
|
return logfs_write_i0(inode, ipage, this_wc);
|
|
}
|
|
|
|
static int logfs_truncate_rec(struct inode *inode, u64 size)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
struct write_control wc = {
|
|
.ofs = li->li_data[INDIRECT_INDEX],
|
|
};
|
|
struct page *page;
|
|
int err;
|
|
|
|
alloc_inode_block(inode);
|
|
|
|
if (!wc.ofs)
|
|
return 0;
|
|
|
|
page = logfs_get_write_page(inode, 0, LEVEL(li->li_height));
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
err = __logfs_truncate_rec(inode, page, &wc, size);
|
|
logfs_put_write_page(page);
|
|
if (err)
|
|
return err;
|
|
|
|
if (li->li_data[INDIRECT_INDEX] != wc.ofs)
|
|
li->li_data[INDIRECT_INDEX] = wc.ofs;
|
|
return 0;
|
|
}
|
|
|
|
static int __logfs_truncate(struct inode *inode, u64 size)
|
|
{
|
|
int ret;
|
|
|
|
if (size >= logfs_factor(logfs_inode(inode)->li_height))
|
|
return 0;
|
|
|
|
ret = logfs_truncate_rec(inode, size);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return logfs_truncate_direct(inode, size);
|
|
}
|
|
|
|
/*
|
|
* Truncate, by changing the segment file, can consume a fair amount
|
|
* of resources. So back off from time to time and do some GC.
|
|
* 8 or 2048 blocks should be well within safety limits even if
|
|
* every single block resided in a different segment.
|
|
*/
|
|
#define TRUNCATE_STEP (8 * 1024 * 1024)
|
|
int logfs_truncate(struct inode *inode, u64 target)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
u64 size = i_size_read(inode);
|
|
int err = 0;
|
|
|
|
size = ALIGN(size, TRUNCATE_STEP);
|
|
while (size > target) {
|
|
if (size > TRUNCATE_STEP)
|
|
size -= TRUNCATE_STEP;
|
|
else
|
|
size = 0;
|
|
if (size < target)
|
|
size = target;
|
|
|
|
logfs_get_wblocks(sb, NULL, 1);
|
|
err = __logfs_truncate(inode, size);
|
|
if (!err)
|
|
err = __logfs_write_inode(inode, NULL, 0);
|
|
logfs_put_wblocks(sb, NULL, 1);
|
|
}
|
|
|
|
if (!err)
|
|
err = vmtruncate(inode, target);
|
|
|
|
/* I don't trust error recovery yet. */
|
|
WARN_ON(err);
|
|
return err;
|
|
}
|
|
|
|
static void move_page_to_inode(struct inode *inode, struct page *page)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
struct logfs_block *block = logfs_block(page);
|
|
|
|
if (!block)
|
|
return;
|
|
|
|
log_blockmove("move_page_to_inode(%llx, %llx, %x)\n",
|
|
block->ino, block->bix, block->level);
|
|
BUG_ON(li->li_block);
|
|
block->ops = &inode_block_ops;
|
|
block->inode = inode;
|
|
li->li_block = block;
|
|
|
|
block->page = NULL;
|
|
if (PagePrivate(page)) {
|
|
ClearPagePrivate(page);
|
|
page_cache_release(page);
|
|
set_page_private(page, 0);
|
|
}
|
|
}
|
|
|
|
static void move_inode_to_page(struct page *page, struct inode *inode)
|
|
{
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
struct logfs_block *block = li->li_block;
|
|
|
|
if (!block)
|
|
return;
|
|
|
|
log_blockmove("move_inode_to_page(%llx, %llx, %x)\n",
|
|
block->ino, block->bix, block->level);
|
|
BUG_ON(PagePrivate(page));
|
|
block->ops = &indirect_block_ops;
|
|
block->page = page;
|
|
|
|
if (!PagePrivate(page)) {
|
|
SetPagePrivate(page);
|
|
page_cache_get(page);
|
|
set_page_private(page, (unsigned long) block);
|
|
}
|
|
|
|
block->inode = NULL;
|
|
li->li_block = NULL;
|
|
}
|
|
|
|
int logfs_read_inode(struct inode *inode)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
struct logfs_super *super = logfs_super(sb);
|
|
struct inode *master_inode = super->s_master_inode;
|
|
struct page *page;
|
|
struct logfs_disk_inode *di;
|
|
u64 ino = inode->i_ino;
|
|
|
|
if (ino << sb->s_blocksize_bits > i_size_read(master_inode))
|
|
return -ENODATA;
|
|
if (!logfs_exist_block(master_inode, ino))
|
|
return -ENODATA;
|
|
|
|
page = read_cache_page(master_inode->i_mapping, ino,
|
|
(filler_t *)logfs_readpage, NULL);
|
|
if (IS_ERR(page))
|
|
return PTR_ERR(page);
|
|
|
|
di = kmap_atomic(page, KM_USER0);
|
|
logfs_disk_to_inode(di, inode);
|
|
kunmap_atomic(di, KM_USER0);
|
|
move_page_to_inode(inode, page);
|
|
page_cache_release(page);
|
|
return 0;
|
|
}
|
|
|
|
/* Caller must logfs_put_write_page(page); */
|
|
static struct page *inode_to_page(struct inode *inode)
|
|
{
|
|
struct inode *master_inode = logfs_super(inode->i_sb)->s_master_inode;
|
|
struct logfs_disk_inode *di;
|
|
struct page *page;
|
|
|
|
BUG_ON(inode->i_ino == LOGFS_INO_MASTER);
|
|
|
|
page = logfs_get_write_page(master_inode, inode->i_ino, 0);
|
|
if (!page)
|
|
return NULL;
|
|
|
|
di = kmap_atomic(page, KM_USER0);
|
|
logfs_inode_to_disk(inode, di);
|
|
kunmap_atomic(di, KM_USER0);
|
|
move_inode_to_page(page, inode);
|
|
return page;
|
|
}
|
|
|
|
static int do_write_inode(struct inode *inode)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
struct inode *master_inode = logfs_super(sb)->s_master_inode;
|
|
loff_t size = (inode->i_ino + 1) << inode->i_sb->s_blocksize_bits;
|
|
struct page *page;
|
|
int err;
|
|
|
|
BUG_ON(inode->i_ino == LOGFS_INO_MASTER);
|
|
/* FIXME: lock inode */
|
|
|
|
if (i_size_read(master_inode) < size)
|
|
i_size_write(master_inode, size);
|
|
|
|
/* TODO: Tell vfs this inode is clean now */
|
|
|
|
page = inode_to_page(inode);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
/* FIXME: transaction is part of logfs_block now. Is that enough? */
|
|
err = logfs_write_buf(master_inode, page, 0);
|
|
if (err)
|
|
move_page_to_inode(inode, page);
|
|
|
|
logfs_put_write_page(page);
|
|
return err;
|
|
}
|
|
|
|
static void logfs_mod_segment_entry(struct super_block *sb, u32 segno,
|
|
int write,
|
|
void (*change_se)(struct logfs_segment_entry *, long),
|
|
long arg)
|
|
{
|
|
struct logfs_super *super = logfs_super(sb);
|
|
struct inode *inode;
|
|
struct page *page;
|
|
struct logfs_segment_entry *se;
|
|
pgoff_t page_no;
|
|
int child_no;
|
|
|
|
page_no = segno >> (sb->s_blocksize_bits - 3);
|
|
child_no = segno & ((sb->s_blocksize >> 3) - 1);
|
|
|
|
inode = super->s_segfile_inode;
|
|
page = logfs_get_write_page(inode, page_no, 0);
|
|
BUG_ON(!page); /* FIXME: We need some reserve page for this case */
|
|
if (!PageUptodate(page))
|
|
logfs_read_block(inode, page, WRITE);
|
|
|
|
if (write)
|
|
alloc_indirect_block(inode, page, 0);
|
|
se = kmap_atomic(page, KM_USER0);
|
|
change_se(se + child_no, arg);
|
|
if (write) {
|
|
logfs_set_alias(sb, logfs_block(page), child_no);
|
|
BUG_ON((int)be32_to_cpu(se[child_no].valid) > super->s_segsize);
|
|
}
|
|
kunmap_atomic(se, KM_USER0);
|
|
|
|
logfs_put_write_page(page);
|
|
}
|
|
|
|
static void __get_segment_entry(struct logfs_segment_entry *se, long _target)
|
|
{
|
|
struct logfs_segment_entry *target = (void *)_target;
|
|
|
|
*target = *se;
|
|
}
|
|
|
|
void logfs_get_segment_entry(struct super_block *sb, u32 segno,
|
|
struct logfs_segment_entry *se)
|
|
{
|
|
logfs_mod_segment_entry(sb, segno, 0, __get_segment_entry, (long)se);
|
|
}
|
|
|
|
static void __set_segment_used(struct logfs_segment_entry *se, long increment)
|
|
{
|
|
u32 valid;
|
|
|
|
valid = be32_to_cpu(se->valid);
|
|
valid += increment;
|
|
se->valid = cpu_to_be32(valid);
|
|
}
|
|
|
|
void logfs_set_segment_used(struct super_block *sb, u64 ofs, int increment)
|
|
{
|
|
struct logfs_super *super = logfs_super(sb);
|
|
u32 segno = ofs >> super->s_segshift;
|
|
|
|
if (!increment)
|
|
return;
|
|
|
|
logfs_mod_segment_entry(sb, segno, 1, __set_segment_used, increment);
|
|
}
|
|
|
|
static void __set_segment_erased(struct logfs_segment_entry *se, long ec_level)
|
|
{
|
|
se->ec_level = cpu_to_be32(ec_level);
|
|
}
|
|
|
|
void logfs_set_segment_erased(struct super_block *sb, u32 segno, u32 ec,
|
|
gc_level_t gc_level)
|
|
{
|
|
u32 ec_level = ec << 4 | (__force u8)gc_level;
|
|
|
|
logfs_mod_segment_entry(sb, segno, 1, __set_segment_erased, ec_level);
|
|
}
|
|
|
|
static void __set_segment_reserved(struct logfs_segment_entry *se, long ignore)
|
|
{
|
|
se->valid = cpu_to_be32(RESERVED);
|
|
}
|
|
|
|
void logfs_set_segment_reserved(struct super_block *sb, u32 segno)
|
|
{
|
|
logfs_mod_segment_entry(sb, segno, 1, __set_segment_reserved, 0);
|
|
}
|
|
|
|
static void __set_segment_unreserved(struct logfs_segment_entry *se,
|
|
long ec_level)
|
|
{
|
|
se->valid = 0;
|
|
se->ec_level = cpu_to_be32(ec_level);
|
|
}
|
|
|
|
void logfs_set_segment_unreserved(struct super_block *sb, u32 segno, u32 ec)
|
|
{
|
|
u32 ec_level = ec << 4;
|
|
|
|
logfs_mod_segment_entry(sb, segno, 1, __set_segment_unreserved,
|
|
ec_level);
|
|
}
|
|
|
|
int __logfs_write_inode(struct inode *inode, struct page *page, long flags)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
int ret;
|
|
|
|
logfs_get_wblocks(sb, page, flags & WF_LOCK);
|
|
ret = do_write_inode(inode);
|
|
logfs_put_wblocks(sb, page, flags & WF_LOCK);
|
|
return ret;
|
|
}
|
|
|
|
static int do_delete_inode(struct inode *inode)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
struct inode *master_inode = logfs_super(sb)->s_master_inode;
|
|
struct page *page;
|
|
int ret;
|
|
|
|
page = logfs_get_write_page(master_inode, inode->i_ino, 0);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
move_inode_to_page(page, inode);
|
|
|
|
logfs_get_wblocks(sb, page, 1);
|
|
ret = __logfs_delete(master_inode, page);
|
|
logfs_put_wblocks(sb, page, 1);
|
|
|
|
logfs_put_write_page(page);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* ZOMBIE inodes have already been deleted before and should remain dead,
|
|
* if it weren't for valid checking. No need to kill them again here.
|
|
*/
|
|
void logfs_evict_inode(struct inode *inode)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
struct logfs_block *block = li->li_block;
|
|
struct page *page;
|
|
|
|
if (!inode->i_nlink) {
|
|
if (!(li->li_flags & LOGFS_IF_ZOMBIE)) {
|
|
li->li_flags |= LOGFS_IF_ZOMBIE;
|
|
if (i_size_read(inode) > 0)
|
|
logfs_truncate(inode, 0);
|
|
do_delete_inode(inode);
|
|
}
|
|
}
|
|
truncate_inode_pages(&inode->i_data, 0);
|
|
end_writeback(inode);
|
|
|
|
/* Cheaper version of write_inode. All changes are concealed in
|
|
* aliases, which are moved back. No write to the medium happens.
|
|
*/
|
|
/* Only deleted files may be dirty at this point */
|
|
BUG_ON(inode->i_state & I_DIRTY && inode->i_nlink);
|
|
if (!block)
|
|
return;
|
|
if ((logfs_super(sb)->s_flags & LOGFS_SB_FLAG_SHUTDOWN)) {
|
|
block->ops->free_block(inode->i_sb, block);
|
|
return;
|
|
}
|
|
|
|
BUG_ON(inode->i_ino < LOGFS_RESERVED_INOS);
|
|
page = inode_to_page(inode);
|
|
BUG_ON(!page); /* FIXME: Use emergency page */
|
|
logfs_put_write_page(page);
|
|
}
|
|
|
|
void btree_write_block(struct logfs_block *block)
|
|
{
|
|
struct inode *inode;
|
|
struct page *page;
|
|
int err, cookie;
|
|
|
|
inode = logfs_safe_iget(block->sb, block->ino, &cookie);
|
|
page = logfs_get_write_page(inode, block->bix, block->level);
|
|
|
|
err = logfs_readpage_nolock(page);
|
|
BUG_ON(err);
|
|
BUG_ON(!PagePrivate(page));
|
|
BUG_ON(logfs_block(page) != block);
|
|
err = __logfs_write_buf(inode, page, 0);
|
|
BUG_ON(err);
|
|
BUG_ON(PagePrivate(page) || page->private);
|
|
|
|
logfs_put_write_page(page);
|
|
logfs_safe_iput(inode, cookie);
|
|
}
|
|
|
|
/**
|
|
* logfs_inode_write - write inode or dentry objects
|
|
*
|
|
* @inode: parent inode (ifile or directory)
|
|
* @buf: object to write (inode or dentry)
|
|
* @n: object size
|
|
* @_pos: object number (file position in blocks/objects)
|
|
* @flags: write flags
|
|
* @lock: 0 if write lock is already taken, 1 otherwise
|
|
* @shadow_tree: shadow below this inode
|
|
*
|
|
* FIXME: All caller of this put a 200-300 byte variable on the stack,
|
|
* only to call here and do a memcpy from that stack variable. A good
|
|
* example of wasted performance and stack space.
|
|
*/
|
|
int logfs_inode_write(struct inode *inode, const void *buf, size_t count,
|
|
loff_t bix, long flags, struct shadow_tree *shadow_tree)
|
|
{
|
|
loff_t pos = bix << inode->i_sb->s_blocksize_bits;
|
|
int err;
|
|
struct page *page;
|
|
void *pagebuf;
|
|
|
|
BUG_ON(pos & (LOGFS_BLOCKSIZE-1));
|
|
BUG_ON(count > LOGFS_BLOCKSIZE);
|
|
page = logfs_get_write_page(inode, bix, 0);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
pagebuf = kmap_atomic(page, KM_USER0);
|
|
memcpy(pagebuf, buf, count);
|
|
flush_dcache_page(page);
|
|
kunmap_atomic(pagebuf, KM_USER0);
|
|
|
|
if (i_size_read(inode) < pos + LOGFS_BLOCKSIZE)
|
|
i_size_write(inode, pos + LOGFS_BLOCKSIZE);
|
|
|
|
err = logfs_write_buf(inode, page, flags);
|
|
logfs_put_write_page(page);
|
|
return err;
|
|
}
|
|
|
|
int logfs_open_segfile(struct super_block *sb)
|
|
{
|
|
struct logfs_super *super = logfs_super(sb);
|
|
struct inode *inode;
|
|
|
|
inode = logfs_read_meta_inode(sb, LOGFS_INO_SEGFILE);
|
|
if (IS_ERR(inode))
|
|
return PTR_ERR(inode);
|
|
super->s_segfile_inode = inode;
|
|
return 0;
|
|
}
|
|
|
|
int logfs_init_rw(struct super_block *sb)
|
|
{
|
|
struct logfs_super *super = logfs_super(sb);
|
|
int min_fill = 3 * super->s_no_blocks;
|
|
|
|
INIT_LIST_HEAD(&super->s_object_alias);
|
|
INIT_LIST_HEAD(&super->s_writeback_list);
|
|
mutex_init(&super->s_write_mutex);
|
|
super->s_block_pool = mempool_create_kmalloc_pool(min_fill,
|
|
sizeof(struct logfs_block));
|
|
super->s_shadow_pool = mempool_create_kmalloc_pool(min_fill,
|
|
sizeof(struct logfs_shadow));
|
|
return 0;
|
|
}
|
|
|
|
void logfs_cleanup_rw(struct super_block *sb)
|
|
{
|
|
struct logfs_super *super = logfs_super(sb);
|
|
|
|
logfs_mempool_destroy(super->s_block_pool);
|
|
logfs_mempool_destroy(super->s_shadow_pool);
|
|
}
|