/* * Read the disk inode attributes into the in-core inode structure. * * For version 5 superblocks, if we are initialising a new inode and we are not * utilising the XFS_MOUNT_IKEEP inode cluster mode, we can simple build the new * inode core with a random generation number. If we are keeping inodes around, * we need to read the inode cluster to get the existing generation number off * disk. Further, if we are using version 4 superblocks (i.e. v1/v2 inode * format) then log recovery is dependent on the di_flushiter field being * initialised from the current on-disk value and hence we must also read the * inode off disk. */ int xfs_iread( xfs_mount_t *mp, xfs_trans_t *tp, xfs_inode_t *ip, uint iget_flags) { xfs_buf_t *bp; xfs_dinode_t *dip; xfs_failaddr_t fa; int error; /* * Fill in the location information in the in-core inode. */ error = xfs_imap(mp, tp, ip->i_ino, &ip->i_imap, iget_flags); if (error) return error; /* shortcut IO on inode allocation if possible */ if ((iget_flags & XFS_IGET_CREATE) && xfs_sb_version_hascrc(&mp->m_sb) && !(mp->m_flags & XFS_MOUNT_IKEEP)) { /* initialise the on-disk inode core */ memset(&ip->i_d, 0, sizeof(ip->i_d)); VFS_I(ip)->i_generation = prandom_u32(); ip->i_d.di_version = 3; return 0; } /* * Get pointers to the on-disk inode and the buffer containing it. */ error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &bp, 0, iget_flags); if (error) return error; /* even unallocated inodes are verified */ fa = xfs_dinode_verify(mp, ip->i_ino, dip); if (fa) { xfs_inode_verifier_error(ip, -EFSCORRUPTED, "dinode", dip, sizeof(*dip), fa); error = -EFSCORRUPTED; goto out_brelse; } /* * If the on-disk inode is already linked to a directory * entry, copy all of the inode into the in-core inode. * xfs_iformat_fork() handles copying in the inode format * specific information. * Otherwise, just get the truly permanent information. */ if (dip->di_mode) { xfs_inode_from_disk(ip, dip); error = xfs_iformat_fork(ip, dip); if (error) { #ifdef DEBUG xfs_alert(mp, "%s: xfs_iformat() returned error %d", __func__, error); #endif /* DEBUG */ goto out_brelse; } } else { /* * Partial initialisation of the in-core inode. Just the bits * that xfs_ialloc won't overwrite or relies on being correct. */ ip->i_d.di_version = dip->di_version; VFS_I(ip)->i_generation = be32_to_cpu(dip->di_gen); ip->i_d.di_flushiter = be16_to_cpu(dip->di_flushiter); /* * Make sure to pull in the mode here as well in * case the inode is released without being used. * This ensures that xfs_inactive() will see that * the inode is already free and not try to mess * with the uninitialized part of it. */ VFS_I(ip)->i_mode = 0; } ASSERT(ip->i_d.di_version >= 2); ip->i_delayed_blks = 0; /* * Mark the buffer containing the inode as something to keep * around for a while. This helps to keep recently accessed * meta-data in-core longer. */ xfs_buf_set_ref(bp, XFS_INO_REF); /* * Use xfs_trans_brelse() to release the buffer containing the on-disk * inode, because it was acquired with xfs_trans_read_buf() in * xfs_imap_to_bp() above. If tp is NULL, this is just a normal * brelse(). If we're within a transaction, then xfs_trans_brelse() * will only release the buffer if it is not dirty within the * transaction. It will be OK to release the buffer in this case, * because inodes on disk are never destroyed and we will be locking the * new in-core inode before putting it in the cache where other * processes can find it. Thus we don't have to worry about the inode * being changed just because we released the buffer. */ out_brelse: xfs_trans_brelse(tp, bp); return error; }
/* * Read the disk inode attributes into the in-core inode structure. * * For version 5 superblocks, if we are initialising a new inode and we are not * utilising the XFS_MOUNT_IKEEP inode cluster mode, we can simple build the new * inode core with a random generation number. If we are keeping inodes around, * we need to read the inode cluster to get the existing generation number off * disk. Further, if we are using version 4 superblocks (i.e. v1/v2 inode * format) then log recovery is dependent on the di_flushiter field being * initialised from the current on-disk value and hence we must also read the * inode off disk. */ int xfs_iread( xfs_mount_t *mp, xfs_trans_t *tp, xfs_inode_t *ip, uint iget_flags) { xfs_buf_t *bp; xfs_dinode_t *dip; int error; /* * Fill in the location information in the in-core inode. */ error = xfs_imap(mp, tp, ip->i_ino, &ip->i_imap, iget_flags); if (error) return error; /* shortcut IO on inode allocation if possible */ if ((iget_flags & XFS_IGET_CREATE) && xfs_sb_version_hascrc(&mp->m_sb) && !(mp->m_flags & XFS_MOUNT_IKEEP)) { /* initialise the on-disk inode core */ memset(&ip->i_d, 0, sizeof(ip->i_d)); ip->i_d.di_magic = XFS_DINODE_MAGIC; ip->i_d.di_gen = prandom_u32(); if (xfs_sb_version_hascrc(&mp->m_sb)) { ip->i_d.di_version = 3; ip->i_d.di_ino = ip->i_ino; uuid_copy(&ip->i_d.di_uuid, &mp->m_sb.sb_uuid); } else ip->i_d.di_version = 2; return 0; } /* * Get pointers to the on-disk inode and the buffer containing it. */ error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &bp, 0, iget_flags); if (error) return error; /* even unallocated inodes are verified */ if (!xfs_dinode_verify(mp, ip, dip)) { xfs_alert(mp, "%s: validation failed for inode %lld failed", __func__, ip->i_ino); XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, dip); error = -EFSCORRUPTED; goto out_brelse; } /* * If the on-disk inode is already linked to a directory * entry, copy all of the inode into the in-core inode. * xfs_iformat_fork() handles copying in the inode format * specific information. * Otherwise, just get the truly permanent information. */ if (dip->di_mode) { xfs_dinode_from_disk(&ip->i_d, dip); error = xfs_iformat_fork(ip, dip); if (error) { #ifdef DEBUG xfs_alert(mp, "%s: xfs_iformat() returned error %d", __func__, error); #endif /* DEBUG */ goto out_brelse; } } else { /* * Partial initialisation of the in-core inode. Just the bits * that xfs_ialloc won't overwrite or relies on being correct. */ ip->i_d.di_magic = be16_to_cpu(dip->di_magic); ip->i_d.di_version = dip->di_version; ip->i_d.di_gen = be32_to_cpu(dip->di_gen); ip->i_d.di_flushiter = be16_to_cpu(dip->di_flushiter); if (dip->di_version == 3) { ip->i_d.di_ino = be64_to_cpu(dip->di_ino); uuid_copy(&ip->i_d.di_uuid, &dip->di_uuid); } /* * Make sure to pull in the mode here as well in * case the inode is released without being used. * This ensures that xfs_inactive() will see that * the inode is already free and not try to mess * with the uninitialized part of it. */ ip->i_d.di_mode = 0; } /* * Automatically convert version 1 inode formats in memory to version 2 * inode format. If the inode is modified, it will get logged and * rewritten as a version 2 inode. We can do this because we set the * superblock feature bit for v2 inodes unconditionally during mount * and it means the reast of the code can assume the inode version is 2 * or higher. */ if (ip->i_d.di_version == 1) { ip->i_d.di_version = 2; memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad)); ip->i_d.di_nlink = ip->i_d.di_onlink; ip->i_d.di_onlink = 0; xfs_set_projid(ip, 0); } ip->i_delayed_blks = 0; /* * Mark the buffer containing the inode as something to keep * around for a while. This helps to keep recently accessed * meta-data in-core longer. */ xfs_buf_set_ref(bp, XFS_INO_REF); /* * Use xfs_trans_brelse() to release the buffer containing the on-disk * inode, because it was acquired with xfs_trans_read_buf() in * xfs_imap_to_bp() above. If tp is NULL, this is just a normal * brelse(). If we're within a transaction, then xfs_trans_brelse() * will only release the buffer if it is not dirty within the * transaction. It will be OK to release the buffer in this case, * because inodes on disk are never destroyed and we will be locking the * new in-core inode before putting it in the cache where other * processes can find it. Thus we don't have to worry about the inode * being changed just because we released the buffer. */ out_brelse: xfs_trans_brelse(tp, bp); return error; }