diff options
Diffstat (limited to 'serverboot/ext2_file_io.c')
| -rw-r--r-- | serverboot/ext2_file_io.c | 983 |
1 files changed, 0 insertions, 983 deletions
diff --git a/serverboot/ext2_file_io.c b/serverboot/ext2_file_io.c deleted file mode 100644 index cb915c4a..00000000 --- a/serverboot/ext2_file_io.c +++ /dev/null @@ -1,983 +0,0 @@ -/* - * Mach Operating System - * Copyright (c) 1991,1990 Carnegie Mellon University - * All Rights Reserved. - * - * Permission to use, copy, modify and distribute this software and its - * documentation is hereby granted, provided that both the copyright - * notice and this permission notice appear in all copies of the - * software, derivative works or modified versions, and any portions - * thereof, and that both notices appear in supporting documentation. - * - * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" - * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR - * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. - * - * Carnegie Mellon requests users of this software to return to - * - * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU - * School of Computer Science - * Carnegie Mellon University - * Pittsburgh PA 15213-3890 - * - * any improvements or extensions that they make and grant Carnegie Mellon - * the rights to redistribute these changes. - */ -/* - * Stand-alone file reading package. - */ - -#include <device/device_types.h> -#include <device/device.h> - -#include <mach/mach_traps.h> -#include <mach/mach_interface.h> - -#include "file_io.h" -#include "ffs_compat.h" - -void ext2_close_file(); /* forward */ - -/* - * Free file buffers, but don't close file. - */ -static void -free_file_buffers(fp) - register struct file *fp; -{ - register int level; - - /* - * Free the indirect blocks - */ - for (level = 0; level < NIADDR; level++) { - if (fp->f_blk[level] != 0) { - (void) vm_deallocate(mach_task_self(), - fp->f_blk[level], - fp->f_blksize[level]); - fp->f_blk[level] = 0; - } - fp->f_blkno[level] = -1; - } - - /* - * Free the data block - */ - if (fp->f_buf != 0) { - (void) vm_deallocate(mach_task_self(), - fp->f_buf, - fp->f_buf_size); - fp->f_buf = 0; - } - fp->f_buf_blkno = -1; -} - -/* - * Read a new inode into a file structure. - */ -static int -read_inode(inumber, fp) - ino_t inumber; - register struct file *fp; -{ - vm_offset_t buf; - mach_msg_type_number_t buf_size; - register - struct ext2_super_block *fs; - daddr_t disk_block; - kern_return_t rc; - - fs = fp->f_fs; - disk_block = ino2blk(fs, fp->f_gd, inumber); - - rc = device_read(fp->f_dev, - 0, - (recnum_t) fsbtodb(fp->f_fs, disk_block), - (int) EXT2_BLOCK_SIZE(fs), - (char **)&buf, - &buf_size); - if (rc != KERN_SUCCESS) - return (rc); - - { - register struct ext2_inode *dp; - - dp = (struct ext2_inode *)buf; - dp += itoo(fs, inumber); - fp->i_ic = *dp; - fp->f_size = dp->i_size; - } - - (void) vm_deallocate(mach_task_self(), buf, buf_size); - - /* - * Clear out the old buffers - */ - free_file_buffers(fp); - - return (0); -} - -/* - * Given an offset in a file, find the disk block number that - * contains that block. - */ -static int -block_map(fp, file_block, disk_block_p) - struct file *fp; - daddr_t file_block; - daddr_t *disk_block_p; /* out */ -{ - int level; - int idx; - daddr_t ind_block_num; - kern_return_t rc; - - vm_offset_t olddata[NIADDR+1]; - vm_size_t oldsize[NIADDR+1]; - - /* - * Index structure of an inode: - * - * i_db[0..NDADDR-1] hold block numbers for blocks - * 0..NDADDR-1 - * - * i_ib[0] index block 0 is the single indirect - * block - * holds block numbers for blocks - * NDADDR .. NDADDR + NINDIR(fs)-1 - * - * i_ib[1] index block 1 is the double indirect - * block - * holds block numbers for INDEX blocks - * for blocks - * NDADDR + NINDIR(fs) .. - * NDADDR + NINDIR(fs) + NINDIR(fs)**2 - 1 - * - * i_ib[2] index block 2 is the triple indirect - * block - * holds block numbers for double-indirect - * blocks for blocks - * NDADDR + NINDIR(fs) + NINDIR(fs)**2 .. - * NDADDR + NINDIR(fs) + NINDIR(fs)**2 - * + NINDIR(fs)**3 - 1 - */ - - mutex_lock(&fp->f_lock); - - if (file_block < NDADDR) { - /* Direct block. */ - *disk_block_p = fp->i_ic.i_block[file_block]; - mutex_unlock(&fp->f_lock); - return (0); - } - - file_block -= NDADDR; - - /* - * nindir[0] = NINDIR - * nindir[1] = NINDIR**2 - * nindir[2] = NINDIR**3 - * etc - */ - for (level = 0; level < NIADDR; level++) { - if (file_block < fp->f_nindir[level]) - break; - file_block -= fp->f_nindir[level]; - } - if (level == NIADDR) { - /* Block number too high */ - mutex_unlock(&fp->f_lock); - return (FS_NOT_IN_FILE); - } - - ind_block_num = fp->i_ic.i_block[level + NDADDR]; - - /* - * Initialize array of blocks to free. - */ - for (idx = 0; idx < NIADDR; idx++) - oldsize[idx] = 0; - - for (; level >= 0; level--) { - - vm_offset_t data; - mach_msg_type_number_t size; - - if (ind_block_num == 0) - break; - - if (fp->f_blkno[level] == ind_block_num) { - /* - * Cache hit. Just pick up the data. - */ - - data = fp->f_blk[level]; - } - else { - /* - * Drop our lock while doing the read. - * (The f_dev and f_fs fields don`t change.) - */ - mutex_unlock(&fp->f_lock); - - rc = device_read(fp->f_dev, - 0, - (recnum_t) fsbtodb(fp->f_fs, ind_block_num), - EXT2_BLOCK_SIZE(fp->f_fs), - (char **)&data, - &size); - if (rc != KERN_SUCCESS) - return (rc); - - /* - * See if we can cache the data. Need a write lock to - * do this. While we hold the write lock, we can`t do - * *anything* which might block for memory. Otherwise - * a non-privileged thread might deadlock with the - * privileged threads. We can`t block while taking the - * write lock. Otherwise a non-privileged thread - * blocked in the vm_deallocate (while holding a read - * lock) will block a privileged thread. For the same - * reason, we can`t take a read lock and then use - * lock_read_to_write. - */ - - mutex_lock(&fp->f_lock); - - olddata[level] = fp->f_blk[level]; - oldsize[level] = fp->f_blksize[level]; - - fp->f_blkno[level] = ind_block_num; - fp->f_blk[level] = data; - fp->f_blksize[level] = size; - - /* - * Return to holding a read lock, and - * dispose of old data. - */ - - } - - if (level > 0) { - idx = file_block / fp->f_nindir[level-1]; - file_block %= fp->f_nindir[level-1]; - } - else - idx = file_block; - - ind_block_num = ((daddr_t *)data)[idx]; - } - - mutex_unlock(&fp->f_lock); - - /* - * After unlocking the file, free any blocks that - * we need to free. - */ - for (idx = 0; idx < NIADDR; idx++) - if (oldsize[idx] != 0) - (void) vm_deallocate(mach_task_self(), - olddata[idx], - oldsize[idx]); - - *disk_block_p = ind_block_num; - return (0); -} - -/* - * Read a portion of a file into an internal buffer. Return - * the location in the buffer and the amount in the buffer. - */ -static int -buf_read_file(fp, offset, buf_p, size_p) - register struct file *fp; - vm_offset_t offset; - vm_offset_t *buf_p; /* out */ - vm_size_t *size_p; /* out */ -{ - register - struct ext2_super_block *fs; - vm_offset_t off; - register daddr_t file_block; - daddr_t disk_block; - int rc; - vm_offset_t block_size; - - if (offset >= fp->i_ic.i_size) - return (FS_NOT_IN_FILE); - - fs = fp->f_fs; - - off = blkoff(fs, offset); - file_block = lblkno(fs, offset); - block_size = blksize(fs, fp, file_block); - - if (file_block != fp->f_buf_blkno) { - rc = block_map(fp, file_block, &disk_block); - if (rc != 0) - return (rc); - - if (fp->f_buf) - (void)vm_deallocate(mach_task_self(), - fp->f_buf, - fp->f_buf_size); - - if (disk_block == 0) { - (void)vm_allocate(mach_task_self(), - &fp->f_buf, - block_size, - TRUE); - fp->f_buf_size = block_size; - } - else { - rc = device_read(fp->f_dev, - 0, - (recnum_t) fsbtodb(fs, disk_block), - (int) block_size, - (char **) &fp->f_buf, - (mach_msg_type_number_t *)&fp->f_buf_size); - } - if (rc) - return (rc); - - fp->f_buf_blkno = file_block; - } - - /* - * Return address of byte in buffer corresponding to - * offset, and size of remainder of buffer after that - * byte. - */ - *buf_p = fp->f_buf + off; - *size_p = block_size - off; - - /* - * But truncate buffer at end of file. - */ - if (*size_p > fp->i_ic.i_size - offset) - *size_p = fp->i_ic.i_size - offset; - - return (0); -} - -/* - * Search a directory for a name and return its - * i_number. - */ -static int -search_directory(name, fp, inumber_p) - char * name; - register struct file *fp; - ino_t *inumber_p; /* out */ -{ - vm_offset_t buf; - vm_size_t buf_size; - vm_offset_t offset; - struct ext2_dir_entry_2 *dp; - int length; - kern_return_t rc; - char tmp_name[256]; - - length = strlen(name); - - offset = 0; - while (offset < fp->i_ic.i_size) { - rc = buf_read_file(fp, offset, &buf, &buf_size); - if (rc != KERN_SUCCESS) - return (rc); - - dp = (struct ext2_dir_entry_2 *)buf; - if (dp->inode != 0) { - strncpy (tmp_name, dp->name, dp->name_len); - tmp_name[dp->name_len] = '\0'; - if (dp->name_len == length && - !strcmp(name, tmp_name)) - { - /* found entry */ - *inumber_p = dp->inode; - return (0); - } - } - offset += dp->rec_len; - } - return (FS_NO_ENTRY); -} - -static int -read_fs(dev, fsp, gdp, gd_size_p) - mach_port_t dev; - struct ext2_super_block **fsp; - struct ext2_group_desc **gdp; - vm_size_t *gd_size_p; -{ - register - struct ext2_super_block *fs; - vm_offset_t buf; - vm_offset_t buf2; - mach_msg_type_number_t buf_size; - mach_msg_type_number_t buf2_size; - int error; - int gd_count; - int gd_blocks; - int gd_size; - int gd_location; - int gd_sector; - - /* - * Read the super block - */ - error = device_read(dev, 0, (recnum_t) SBLOCK, SBSIZE, - (char **) &buf, &buf_size); - if (error) - return (error); - - /* - * Check the superblock - */ - fs = (struct ext2_super_block *)buf; - if (fs->s_magic != EXT2_SUPER_MAGIC) { - (void) vm_deallocate(mach_task_self(), buf, buf_size); - return (FS_INVALID_FS); - } - - *fsp = fs; - - /* - * Compute the groups informations - */ - gd_count = (fs->s_blocks_count - fs->s_first_data_block + - fs->s_blocks_per_group - 1) / fs->s_blocks_per_group; - gd_blocks = (gd_count + EXT2_DESC_PER_BLOCK(fs) - 1) / - EXT2_DESC_PER_BLOCK(fs); - gd_size = gd_blocks * EXT2_BLOCK_SIZE(fs); - gd_location = fs->s_first_data_block + 1; - gd_sector = (gd_location * EXT2_BLOCK_SIZE(fs)) / DEV_BSIZE; - - /* - * Read the groups descriptors - */ - error = device_read(dev, 0, (recnum_t) gd_sector, gd_size, - (char **) &buf2, &buf2_size); - if (error) { - (void) vm_deallocate(mach_task_self(), buf, buf_size); - return error; - } - - *gdp = (struct ext2_group_desc *) buf2; - *gd_size_p = gd_size; - - return 0; -} - -static int -mount_fs(fp) - register struct file *fp; -{ - register struct ext2_super_block *fs; - int error; - - error = read_fs(fp->f_dev, &fp->f_fs, &fp->f_gd, &fp->f_gd_size); - if (error) - return (error); - - fs = fp->f_fs; - - /* - * Calculate indirect block levels. - */ - { - register int mult; - register int level; - - mult = 1; - for (level = 0; level < NIADDR; level++) { - mult *= NINDIR(fs); - fp->f_nindir[level] = mult; - } - } - - return (0); -} - -static void -unmount_fs(fp) - register struct file *fp; -{ - if (file_is_structured(fp)) { - (void) vm_deallocate(mach_task_self(), - (vm_offset_t) fp->f_fs, - SBSIZE); - (void) vm_deallocate(mach_task_self(), - (vm_offset_t) fp->f_gd, - fp->f_gd_size); - fp->f_fs = 0; - } -} - -/* - * Open a file. - */ -int -ext2_open_file(master_device_port, path, fp) - mach_port_t master_device_port; - char * path; - struct file *fp; -{ -#define RETURN(code) { rc = (code); goto exit; } - - register char *cp, *component; - register int c; /* char */ - register int rc; - ino_t inumber, parent_inumber; - int nlinks = 0; - - char namebuf[MAXPATHLEN+1]; - - if (path == 0 || *path == '\0') { - return FS_NO_ENTRY; - } - - /* - * Copy name into buffer to allow modifying it. - */ - strcpy(namebuf, path); - - /* - * Look for '/dev/xxx' at start of path, for - * root device. - */ - if (!strprefix(namebuf, "/dev/")) { - printf("no device name\n"); - return FS_NO_ENTRY; - } - - cp = namebuf + 5; /* device */ - component = cp; - while ((c = *cp) != '\0' && c != '/') { - cp++; - } - *cp = '\0'; - - bzero (fp, sizeof (struct file)); - - rc = device_open(master_device_port, - D_READ|D_WRITE, - component, - &fp->f_dev); - if (rc) - return rc; - - if (c == 0) { - fp->f_fs = 0; - goto out_ok; - } - - *cp = c; - - rc = mount_fs(fp); - if (rc) - return rc; - - inumber = (ino_t) ROOTINO; - if ((rc = read_inode(inumber, fp)) != 0) { - printf("can't read root inode\n"); - goto exit; - } - - while (*cp) { - - /* - * Check that current node is a directory. - */ - if ((fp->i_ic.i_mode & IFMT) != IFDIR) - RETURN (FS_NOT_DIRECTORY); - - /* - * Remove extra separators - */ - while (*cp == '/') - cp++; - - /* - * Get next component of path name. - */ - component = cp; - { - register int len = 0; - - while ((c = *cp) != '\0' && c != '/') { - if (len++ > MAXNAMLEN) - RETURN (FS_NAME_TOO_LONG); - if (c & 0200) - RETURN (FS_INVALID_PARAMETER); - cp++; - } - *cp = 0; - } - - /* - * Look up component in current directory. - * Save directory inumber in case we find a - * symbolic link. - */ - parent_inumber = inumber; - rc = search_directory(component, fp, &inumber); - if (rc) { - printf("%s: not found\n", path); - goto exit; - } - *cp = c; - - /* - * Open next component. - */ - if ((rc = read_inode(inumber, fp)) != 0) - goto exit; - - /* - * Check for symbolic link. - */ - if ((fp->i_ic.i_mode & IFMT) == IFLNK) { - - int link_len = fp->i_ic.i_size; - int len; - - len = strlen(cp) + 1; - - if (link_len + len >= MAXPATHLEN - 1) - RETURN (FS_NAME_TOO_LONG); - - if (++nlinks > MAXSYMLINKS) - RETURN (FS_SYMLINK_LOOP); - - memmove(&namebuf[link_len], cp, len); - -#ifdef IC_FASTLINK - if (fp->i_ic.i_blocks == 0) { - bcopy(fp->i_ic.i_block, namebuf, (unsigned) link_len); - } - else -#endif /* IC_FASTLINK */ - { - /* - * Read file for symbolic link - */ - vm_offset_t buf; - mach_msg_type_number_t buf_size; - daddr_t disk_block; - register struct ext2_super_block *fs = fp->f_fs; - - (void) block_map(fp, (daddr_t)0, &disk_block); - rc = device_read(fp->f_dev, - 0, - (recnum_t) fsbtodb(fs, disk_block), - (int) blksize(fs, fp, 0), - (char **) &buf, - &buf_size); - if (rc) - goto exit; - - bcopy((char *)buf, namebuf, (unsigned)link_len); - (void) vm_deallocate(mach_task_self(), buf, buf_size); - } - - /* - * If relative pathname, restart at parent directory. - * If absolute pathname, restart at root. - * If pathname begins '/dev/<device>/', - * restart at root of that device. - */ - cp = namebuf; - if (*cp != '/') { - inumber = parent_inumber; - } - else if (!strprefix(cp, "/dev/")) { - inumber = (ino_t)ROOTINO; - } - else { - cp += 5; - component = cp; - while ((c = *cp) != '\0' && c != '/') { - cp++; - } - *cp = '\0'; - - /* - * Unmount current file system and free buffers. - */ - ext2_close_file(fp); - - /* - * Open new root device. - */ - rc = device_open(master_device_port, - D_READ, - component, - &fp->f_dev); - if (rc) - return (rc); - - if (c == 0) { - fp->f_fs = 0; - goto out_ok; - } - - *cp = c; - - rc = mount_fs(fp); - if (rc) - return (rc); - - inumber = (ino_t)ROOTINO; - } - if ((rc = read_inode(inumber, fp)) != 0) - goto exit; - } - } - - /* - * Found terminal component. - */ - out_ok: - mutex_init(&fp->f_lock); - return 0; - - /* - * At error exit, close file to free storage. - */ - exit: - ext2_close_file(fp); - return rc; -} - -/* - * Close file - free all storage used. - */ -void -ext2_close_file(fp) - register struct file *fp; -{ - register int i; - - /* - * Free the disk super-block. - */ - unmount_fs(fp); - - /* - * Free the inode and data buffers. - */ - free_file_buffers(fp); -} - -int -ext2_file_is_directory(struct file *fp) -{ - return (fp->i_ic.i_mode & IFMT) == IFDIR; -} - -int -ext2_file_is_regular(struct file *fp) -{ - return (fp->i_ic.i_mode & IFMT) == IFREG; -} - -/* - * Copy a portion of a file into kernel memory. - * Cross block boundaries when necessary. - */ -int -ext2_read_file(fp, offset, start, size, resid) - register struct file *fp; - vm_offset_t offset; - vm_offset_t start; - vm_size_t size; - vm_size_t *resid; /* out */ -{ - int rc; - register vm_size_t csize; - vm_offset_t buf; - vm_size_t buf_size; - - while (size != 0) { - rc = buf_read_file(fp, offset, &buf, &buf_size); - if (rc) - return (rc); - - csize = size; - if (csize > buf_size) - csize = buf_size; - if (csize == 0) - break; - - bcopy((char *)buf, (char *)start, csize); - - offset += csize; - start += csize; - size -= csize; - } - if (resid) - *resid = size; - - return (0); -} - -/* simple utility: only works for 2^n */ -static int -log2(n) - register unsigned int n; -{ - register int i = 0; - - while ((n & 1) == 0) { - i++; - n >>= 1; - } - return i; -} - -/* - * Make an empty file_direct for a device. - */ -int -ext2_open_file_direct(dev, fdp, is_structured) - mach_port_t dev; - register struct file_direct *fdp; - boolean_t is_structured; -{ - struct ext2_super_block *fs; - struct ext2_group_desc *gd; - vm_size_t gd_size; - int rc; - - if (!is_structured) { - fdp->fd_dev = dev; - fdp->fd_blocks = (daddr_t *) 0; - fdp->fd_bsize = vm_page_size; - fdp->fd_bshift = log2(vm_page_size); - fdp->fd_fsbtodb = 0; /* later */ - fdp->fd_size = 0; /* later */ - return 0; - } - - rc = read_fs(dev, &fs, &gd, &gd_size); - if (rc) - return rc; - - fdp->fd_dev = dev; - fdp->fd_blocks = (daddr_t *) 0; - fdp->fd_size = 0; - fdp->fd_bsize = EXT2_BLOCK_SIZE(fs); - fdp->fd_bshift = log2(fdp->fd_bsize); - fdp->fd_fsbtodb = log2(fdp->fd_bsize / DEV_BSIZE); - - (void) vm_deallocate(mach_task_self(), - (vm_offset_t) fs, - SBSIZE); - (void) vm_deallocate(mach_task_self(), - (vm_offset_t) gd, - gd_size); - - return 0; -} - -/* - * Add blocks from a file to a file_direct. - */ -int -ext2_add_file_direct(fdp, fp) - register struct file_direct *fdp; - register struct file *fp; -{ - register struct ext2_super_block *fs; - long num_blocks, i; - vm_offset_t buffer; - vm_size_t size; - int rc; - - /* the file must be on the same device */ - - if (fdp->fd_dev != fp->f_dev) - return FS_INVALID_FS; - - if (!file_is_structured(fp)) { - int result[DEV_GET_SIZE_COUNT]; - natural_t count; - - count = DEV_GET_SIZE_COUNT; - rc = device_get_status( fdp->fd_dev, DEV_GET_SIZE, - result, &count); - if (rc) - return rc; - fdp->fd_size = result[DEV_GET_SIZE_DEVICE_SIZE] >> fdp->fd_bshift; - fdp->fd_fsbtodb = log2(fdp->fd_bsize/result[DEV_GET_SIZE_RECORD_SIZE]); - return 0; - } - - /* it must hold a file system */ - - fs = fp->f_fs; -/* - if (fdp->fd_bsize != fs->fs_bsize || - fdp->fd_fsbtodb != fs->fs_fsbtodb) -*/ - if (fdp->fd_bsize != EXT2_BLOCK_SIZE(fs)) - return FS_INVALID_FS; - - /* calculate number of blocks in the file, ignoring fragments */ - - num_blocks = lblkno(fs, fp->i_ic.i_size); - - /* allocate memory for a bigger array */ - - size = (num_blocks + fdp->fd_size) * sizeof(daddr_t); - rc = vm_allocate(mach_task_self(), &buffer, size, TRUE); - if (rc != KERN_SUCCESS) - return rc; - - /* lookup new block addresses */ - - for (i = 0; i < num_blocks; i++) { - daddr_t disk_block; - - rc = block_map(fp, (daddr_t) i, &disk_block); - if (rc != 0) { - (void) vm_deallocate(mach_task_self(), buffer, size); - return rc; - } - - ((daddr_t *) buffer)[fdp->fd_size + i] = disk_block; - } - - /* copy old addresses and install the new array */ - - if (fdp->fd_blocks != 0) { - bcopy((char *) fdp->fd_blocks, (char *) buffer, - fdp->fd_size * sizeof(daddr_t)); - - (void) vm_deallocate(mach_task_self(), - (vm_offset_t) fdp->fd_blocks, - (vm_size_t) (fdp->fd_size * sizeof(daddr_t))); - } - fdp->fd_blocks = (daddr_t *) buffer; - fdp->fd_size += num_blocks; - - /* deallocate cached blocks */ - - free_file_buffers(fp); - - return 0; -} - -int -ext2_remove_file_direct(fdp) - struct file_direct *fdp; -{ - if (fdp->fd_blocks) - (void) vm_deallocate(mach_task_self(), - (vm_offset_t) fdp->fd_blocks, - (vm_size_t) (fdp->fd_size * sizeof(daddr_t))); - fdp->fd_blocks = 0; /* sanity */ - /* xxx should lose a ref to fdp->fd_dev here (and elsewhere) xxx */ -} |