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author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/ufs/ialloc.c |
Initial import
Diffstat (limited to 'fs/ufs/ialloc.c')
-rw-r--r-- | fs/ufs/ialloc.c | 353 |
1 files changed, 353 insertions, 0 deletions
diff --git a/fs/ufs/ialloc.c b/fs/ufs/ialloc.c new file mode 100644 index 000000000..fd0203ce1 --- /dev/null +++ b/fs/ufs/ialloc.c @@ -0,0 +1,353 @@ +/* + * linux/fs/ufs/ialloc.c + * + * Copyright (c) 1998 + * Daniel Pirkl <daniel.pirkl@email.cz> + * Charles University, Faculty of Mathematics and Physics + * + * from + * + * linux/fs/ext2/ialloc.c + * + * Copyright (C) 1992, 1993, 1994, 1995 + * Remy Card (card@masi.ibp.fr) + * Laboratoire MASI - Institut Blaise Pascal + * Universite Pierre et Marie Curie (Paris VI) + * + * BSD ufs-inspired inode and directory allocation by + * Stephen Tweedie (sct@dcs.ed.ac.uk), 1993 + * Big-endian to little-endian byte-swapping/bitmaps by + * David S. Miller (davem@caip.rutgers.edu), 1995 + * + * UFS2 write support added by + * Evgeniy Dushistov <dushistov@mail.ru>, 2007 + */ + +#include <linux/fs.h> +#include <linux/time.h> +#include <linux/stat.h> +#include <linux/string.h> +#include <linux/buffer_head.h> +#include <linux/sched.h> +#include <linux/bitops.h> +#include <asm/byteorder.h> + +#include "ufs_fs.h" +#include "ufs.h" +#include "swab.h" +#include "util.h" + +/* + * NOTE! When we get the inode, we're the only people + * that have access to it, and as such there are no + * race conditions we have to worry about. The inode + * is not on the hash-lists, and it cannot be reached + * through the filesystem because the directory entry + * has been deleted earlier. + * + * HOWEVER: we must make sure that we get no aliases, + * which means that we have to call "clear_inode()" + * _before_ we mark the inode not in use in the inode + * bitmaps. Otherwise a newly created file might use + * the same inode number (not actually the same pointer + * though), and then we'd have two inodes sharing the + * same inode number and space on the harddisk. + */ +void ufs_free_inode (struct inode * inode) +{ + struct super_block * sb; + struct ufs_sb_private_info * uspi; + struct ufs_cg_private_info * ucpi; + struct ufs_cylinder_group * ucg; + int is_directory; + unsigned ino, cg, bit; + + UFSD("ENTER, ino %lu\n", inode->i_ino); + + sb = inode->i_sb; + uspi = UFS_SB(sb)->s_uspi; + + ino = inode->i_ino; + + mutex_lock(&UFS_SB(sb)->s_lock); + + if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) { + ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino); + mutex_unlock(&UFS_SB(sb)->s_lock); + return; + } + + cg = ufs_inotocg (ino); + bit = ufs_inotocgoff (ino); + ucpi = ufs_load_cylinder (sb, cg); + if (!ucpi) { + mutex_unlock(&UFS_SB(sb)->s_lock); + return; + } + ucg = ubh_get_ucg(UCPI_UBH(ucpi)); + if (!ufs_cg_chkmagic(sb, ucg)) + ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number"); + + ucg->cg_time = cpu_to_fs32(sb, get_seconds()); + + is_directory = S_ISDIR(inode->i_mode); + + if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit)) + ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino); + else { + ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit); + if (ino < ucpi->c_irotor) + ucpi->c_irotor = ino; + fs32_add(sb, &ucg->cg_cs.cs_nifree, 1); + uspi->cs_total.cs_nifree++; + fs32_add(sb, &UFS_SB(sb)->fs_cs(cg).cs_nifree, 1); + + if (is_directory) { + fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1); + uspi->cs_total.cs_ndir--; + fs32_sub(sb, &UFS_SB(sb)->fs_cs(cg).cs_ndir, 1); + } + } + + ubh_mark_buffer_dirty (USPI_UBH(uspi)); + ubh_mark_buffer_dirty (UCPI_UBH(ucpi)); + if (sb->s_flags & MS_SYNCHRONOUS) + ubh_sync_block(UCPI_UBH(ucpi)); + + ufs_mark_sb_dirty(sb); + mutex_unlock(&UFS_SB(sb)->s_lock); + UFSD("EXIT\n"); +} + +/* + * Nullify new chunk of inodes, + * BSD people also set ui_gen field of inode + * during nullification, but we not care about + * that because of linux ufs do not support NFS + */ +static void ufs2_init_inodes_chunk(struct super_block *sb, + struct ufs_cg_private_info *ucpi, + struct ufs_cylinder_group *ucg) +{ + struct buffer_head *bh; + struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi; + sector_t beg = uspi->s_sbbase + + ufs_inotofsba(ucpi->c_cgx * uspi->s_ipg + + fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk)); + sector_t end = beg + uspi->s_fpb; + + UFSD("ENTER cgno %d\n", ucpi->c_cgx); + + for (; beg < end; ++beg) { + bh = sb_getblk(sb, beg); + lock_buffer(bh); + memset(bh->b_data, 0, sb->s_blocksize); + set_buffer_uptodate(bh); + mark_buffer_dirty(bh); + unlock_buffer(bh); + if (sb->s_flags & MS_SYNCHRONOUS) + sync_dirty_buffer(bh); + brelse(bh); + } + + fs32_add(sb, &ucg->cg_u.cg_u2.cg_initediblk, uspi->s_inopb); + ubh_mark_buffer_dirty(UCPI_UBH(ucpi)); + if (sb->s_flags & MS_SYNCHRONOUS) + ubh_sync_block(UCPI_UBH(ucpi)); + + UFSD("EXIT\n"); +} + +/* + * There are two policies for allocating an inode. If the new inode is + * a directory, then a forward search is made for a block group with both + * free space and a low directory-to-inode ratio; if that fails, then of + * the groups with above-average free space, that group with the fewest + * directories already is chosen. + * + * For other inodes, search forward from the parent directory's block + * group to find a free inode. + */ +struct inode *ufs_new_inode(struct inode *dir, umode_t mode) +{ + struct super_block * sb; + struct ufs_sb_info * sbi; + struct ufs_sb_private_info * uspi; + struct ufs_cg_private_info * ucpi; + struct ufs_cylinder_group * ucg; + struct inode * inode; + unsigned cg, bit, i, j, start; + struct ufs_inode_info *ufsi; + int err = -ENOSPC; + + UFSD("ENTER\n"); + + /* Cannot create files in a deleted directory */ + if (!dir || !dir->i_nlink) + return ERR_PTR(-EPERM); + sb = dir->i_sb; + inode = new_inode(sb); + if (!inode) + return ERR_PTR(-ENOMEM); + ufsi = UFS_I(inode); + sbi = UFS_SB(sb); + uspi = sbi->s_uspi; + + mutex_lock(&sbi->s_lock); + + /* + * Try to place the inode in its parent directory + */ + i = ufs_inotocg(dir->i_ino); + if (sbi->fs_cs(i).cs_nifree) { + cg = i; + goto cg_found; + } + + /* + * Use a quadratic hash to find a group with a free inode + */ + for ( j = 1; j < uspi->s_ncg; j <<= 1 ) { + i += j; + if (i >= uspi->s_ncg) + i -= uspi->s_ncg; + if (sbi->fs_cs(i).cs_nifree) { + cg = i; + goto cg_found; + } + } + + /* + * That failed: try linear search for a free inode + */ + i = ufs_inotocg(dir->i_ino) + 1; + for (j = 2; j < uspi->s_ncg; j++) { + i++; + if (i >= uspi->s_ncg) + i = 0; + if (sbi->fs_cs(i).cs_nifree) { + cg = i; + goto cg_found; + } + } + + goto failed; + +cg_found: + ucpi = ufs_load_cylinder (sb, cg); + if (!ucpi) { + err = -EIO; + goto failed; + } + ucg = ubh_get_ucg(UCPI_UBH(ucpi)); + if (!ufs_cg_chkmagic(sb, ucg)) + ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number"); + + start = ucpi->c_irotor; + bit = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, uspi->s_ipg, start); + if (!(bit < uspi->s_ipg)) { + bit = ubh_find_first_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, start); + if (!(bit < start)) { + ufs_error (sb, "ufs_new_inode", + "cylinder group %u corrupted - error in inode bitmap\n", cg); + err = -EIO; + goto failed; + } + } + UFSD("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg); + if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit)) + ubh_setbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit); + else { + ufs_panic (sb, "ufs_new_inode", "internal error"); + err = -EIO; + goto failed; + } + + if (uspi->fs_magic == UFS2_MAGIC) { + u32 initediblk = fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk); + + if (bit + uspi->s_inopb > initediblk && + initediblk < fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_niblk)) + ufs2_init_inodes_chunk(sb, ucpi, ucg); + } + + fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1); + uspi->cs_total.cs_nifree--; + fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1); + + if (S_ISDIR(mode)) { + fs32_add(sb, &ucg->cg_cs.cs_ndir, 1); + uspi->cs_total.cs_ndir++; + fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1); + } + ubh_mark_buffer_dirty (USPI_UBH(uspi)); + ubh_mark_buffer_dirty (UCPI_UBH(ucpi)); + if (sb->s_flags & MS_SYNCHRONOUS) + ubh_sync_block(UCPI_UBH(ucpi)); + ufs_mark_sb_dirty(sb); + + inode->i_ino = cg * uspi->s_ipg + bit; + inode_init_owner(inode, dir, mode); + inode->i_blocks = 0; + inode->i_generation = 0; + inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC; + ufsi->i_flags = UFS_I(dir)->i_flags; + ufsi->i_lastfrag = 0; + ufsi->i_shadow = 0; + ufsi->i_osync = 0; + ufsi->i_oeftflag = 0; + ufsi->i_dir_start_lookup = 0; + memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1)); + if (insert_inode_locked(inode) < 0) { + err = -EIO; + goto failed; + } + mark_inode_dirty(inode); + + if (uspi->fs_magic == UFS2_MAGIC) { + struct buffer_head *bh; + struct ufs2_inode *ufs2_inode; + + /* + * setup birth date, we do it here because of there is no sense + * to hold it in struct ufs_inode_info, and lose 64 bit + */ + bh = sb_bread(sb, uspi->s_sbbase + ufs_inotofsba(inode->i_ino)); + if (!bh) { + ufs_warning(sb, "ufs_read_inode", + "unable to read inode %lu\n", + inode->i_ino); + err = -EIO; + goto fail_remove_inode; + } + lock_buffer(bh); + ufs2_inode = (struct ufs2_inode *)bh->b_data; + ufs2_inode += ufs_inotofsbo(inode->i_ino); + ufs2_inode->ui_birthtime = cpu_to_fs64(sb, CURRENT_TIME.tv_sec); + ufs2_inode->ui_birthnsec = cpu_to_fs32(sb, CURRENT_TIME.tv_nsec); + mark_buffer_dirty(bh); + unlock_buffer(bh); + if (sb->s_flags & MS_SYNCHRONOUS) + sync_dirty_buffer(bh); + brelse(bh); + } + mutex_unlock(&sbi->s_lock); + + UFSD("allocating inode %lu\n", inode->i_ino); + UFSD("EXIT\n"); + return inode; + +fail_remove_inode: + mutex_unlock(&sbi->s_lock); + clear_nlink(inode); + unlock_new_inode(inode); + iput(inode); + UFSD("EXIT (FAILED): err %d\n", err); + return ERR_PTR(err); +failed: + mutex_unlock(&sbi->s_lock); + make_bad_inode(inode); + iput (inode); + UFSD("EXIT (FAILED): err %d\n", err); + return ERR_PTR(err); +} |