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Diffstat (limited to 'fs/ufs/ialloc.c')
-rw-r--r-- | fs/ufs/ialloc.c | 302 |
1 files changed, 302 insertions, 0 deletions
diff --git a/fs/ufs/ialloc.c b/fs/ufs/ialloc.c new file mode 100644 index 0000000..61a6b15 --- /dev/null +++ b/fs/ufs/ialloc.c @@ -0,0 +1,302 @@ +/* + * 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 + */ + +#include <linux/fs.h> +#include <linux/ufs_fs.h> +#include <linux/time.h> +#include <linux/stat.h> +#include <linux/string.h> +#include <linux/quotaops.h> +#include <linux/buffer_head.h> +#include <linux/sched.h> +#include <linux/bitops.h> +#include <asm/byteorder.h> + +#include "swab.h" +#include "util.h" + +#undef UFS_IALLOC_DEBUG + +#ifdef UFS_IALLOC_DEBUG +#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x; +#else +#define UFSD(x) +#endif + +/* + * 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_super_block_first * usb1; + 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; + usb1 = ubh_get_usb_first(USPI_UBH); + + ino = inode->i_ino; + + lock_super (sb); + + if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) { + ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino); + unlock_super (sb); + return; + } + + cg = ufs_inotocg (ino); + bit = ufs_inotocgoff (ino); + ucpi = ufs_load_cylinder (sb, cg); + if (!ucpi) { + unlock_super (sb); + return; + } + ucg = ubh_get_ucg(UCPI_UBH); + 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); + + DQUOT_FREE_INODE(inode); + DQUOT_DROP(inode); + + clear_inode (inode); + + if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit)) + ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino); + else { + ubh_clrbit (UCPI_UBH, ucpi->c_iusedoff, bit); + if (ino < ucpi->c_irotor) + ucpi->c_irotor = ino; + fs32_add(sb, &ucg->cg_cs.cs_nifree, 1); + fs32_add(sb, &usb1->fs_cstotal.cs_nifree, 1); + fs32_add(sb, &UFS_SB(sb)->fs_cs(cg).cs_nifree, 1); + + if (is_directory) { + fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1); + fs32_sub(sb, &usb1->fs_cstotal.cs_ndir, 1); + fs32_sub(sb, &UFS_SB(sb)->fs_cs(cg).cs_ndir, 1); + } + } + + ubh_mark_buffer_dirty (USPI_UBH); + ubh_mark_buffer_dirty (UCPI_UBH); + if (sb->s_flags & MS_SYNCHRONOUS) { + ubh_wait_on_buffer (UCPI_UBH); + ubh_ll_rw_block (WRITE, 1, (struct ufs_buffer_head **) &ucpi); + ubh_wait_on_buffer (UCPI_UBH); + } + + sb->s_dirt = 1; + unlock_super (sb); + 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, int mode) +{ + struct super_block * sb; + struct ufs_sb_info * sbi; + struct ufs_sb_private_info * uspi; + struct ufs_super_block_first * usb1; + 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; + + 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; + usb1 = ubh_get_usb_first(USPI_UBH); + + lock_super (sb); + + /* + * 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) + goto failed; + ucg = ubh_get_ucg(UCPI_UBH); + 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->c_iusedoff, uspi->s_ipg, start); + if (!(bit < uspi->s_ipg)) { + bit = ubh_find_first_zero_bit (UCPI_UBH, ucpi->c_iusedoff, start); + if (!(bit < start)) { + ufs_error (sb, "ufs_new_inode", + "cylinder group %u corrupted - error in inode bitmap\n", cg); + goto failed; + } + } + UFSD(("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg)) + if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit)) + ubh_setbit (UCPI_UBH, ucpi->c_iusedoff, bit); + else { + ufs_panic (sb, "ufs_new_inode", "internal error"); + goto failed; + } + + fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1); + fs32_sub(sb, &usb1->fs_cstotal.cs_nifree, 1); + fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1); + + if (S_ISDIR(mode)) { + fs32_add(sb, &ucg->cg_cs.cs_ndir, 1); + fs32_add(sb, &usb1->fs_cstotal.cs_ndir, 1); + fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1); + } + + ubh_mark_buffer_dirty (USPI_UBH); + ubh_mark_buffer_dirty (UCPI_UBH); + if (sb->s_flags & MS_SYNCHRONOUS) { + ubh_wait_on_buffer (UCPI_UBH); + ubh_ll_rw_block (WRITE, 1, (struct ufs_buffer_head **) &ucpi); + ubh_wait_on_buffer (UCPI_UBH); + } + sb->s_dirt = 1; + + inode->i_mode = mode; + inode->i_uid = current->fsuid; + if (dir->i_mode & S_ISGID) { + inode->i_gid = dir->i_gid; + if (S_ISDIR(mode)) + inode->i_mode |= S_ISGID; + } else + inode->i_gid = current->fsgid; + + inode->i_ino = cg * uspi->s_ipg + bit; + inode->i_blksize = PAGE_SIZE; /* This is the optimal IO size (for stat), not the fs block size */ + inode->i_blocks = 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_gen = 0; + ufsi->i_shadow = 0; + ufsi->i_osync = 0; + ufsi->i_oeftflag = 0; + memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1)); + + insert_inode_hash(inode); + mark_inode_dirty(inode); + + unlock_super (sb); + + if (DQUOT_ALLOC_INODE(inode)) { + DQUOT_DROP(inode); + inode->i_flags |= S_NOQUOTA; + inode->i_nlink = 0; + iput(inode); + return ERR_PTR(-EDQUOT); + } + + UFSD(("allocating inode %lu\n", inode->i_ino)) + UFSD(("EXIT\n")) + return inode; + +failed: + unlock_super (sb); + make_bad_inode(inode); + iput (inode); + UFSD(("EXIT (FAILED)\n")) + return ERR_PTR(-ENOSPC); +} |