libminixfs: better support for read errors and EOF
- The lmfs_get_block*(3) API calls may now return an error. The idea is to encourage a next generation of file system services to do a better job at dealing with block read errors than the MFS-derived implementations do. These existing file systems have been changed to panic immediately upon getting a block read error, in order to let unchecked errors cause corruption. Note that libbdev already retries failing I/O operations a few times first. - The libminixfs block device I/O module (bio.c) now deals properly with end-of-file conditions on block devices. Since a device or partition size may not be a multiple of the root file system's block size, support for partial block retrival has been added, with a new internal lmfs_get_partial_block(3) call. A new test program, test85, tests the new handling of EOF conditions when reading, writing, and memory-mapping a block device. Change-Id: I05e35b6b8851488328a2679da635ebba0c6d08ce
This commit is contained in:
David van Moolenbroek
parent
1311233cfb
commit
6c46a77d95
23 changed files with 872 additions and 193 deletions
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@ -6306,6 +6306,7 @@
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./usr/tests/minix-posix/test82 minix-sys
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./usr/tests/minix-posix/test83 minix-sys
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./usr/tests/minix-posix/test84 minix-sys
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./usr/tests/minix-posix/test85 minix-sys
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./usr/tests/minix-posix/test9 minix-sys
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./usr/tests/minix-posix/testinterp minix-sys
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./usr/tests/minix-posix/testisofs minix-sys
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@ -17,6 +17,7 @@
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#include <lib.h>
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#include <limits.h>
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#include <errno.h>
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#include <assert.h>
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#include <minix/syslib.h>
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#include <minix/sysutil.h>
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@ -1,7 +1,6 @@
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#ifndef EXT2_PROTO_H
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#define EXT2_PROTO_H
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#define get_block(d, n, t) lmfs_get_block(d, n, t)
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#define put_block(n) lmfs_put_block(n)
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/* Function prototypes. */
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@ -95,6 +94,7 @@ struct group_desc* get_group_desc(unsigned int bnum);
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int fs_utime(ino_t ino, struct timespec *atime, struct timespec *mtime);
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/* utility.c */
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struct buf *get_block(dev_t dev, block_t block, int how);
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unsigned conv2(int norm, int w);
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long conv4(int norm, long x);
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int ansi_strcmp(register const char* ansi_s, register const char *s2,
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@ -48,8 +48,6 @@ ssize_t fs_readwrite(ino_t ino_nr, struct fsdriver_data *data, size_t nrbytes,
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f_size = rip->i_size;
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if (f_size < 0) f_size = MAX_FILE_POS;
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lmfs_reset_rdwt_err();
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if (call == FSC_WRITE) {
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/* Check in advance to see if file will grow too big. */
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if (position > (off_t) (rip->i_sp->s_max_size - nrbytes))
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@ -74,8 +72,7 @@ ssize_t fs_readwrite(ino_t ino_nr, struct fsdriver_data *data, size_t nrbytes,
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r = rw_chunk(rip, ((u64_t)((unsigned long)position)), off, chunk,
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nrbytes, call, data, cum_io, block_size, &completed);
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if (r != OK) break; /* EOF reached */
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if (lmfs_rdwt_err() < 0) break;
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if (r != OK) break;
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/* Update counters and pointers. */
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nrbytes -= chunk; /* bytes yet to be read */
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@ -92,9 +89,6 @@ ssize_t fs_readwrite(ino_t ino_nr, struct fsdriver_data *data, size_t nrbytes,
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rip->i_seek = NO_SEEK;
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if (lmfs_rdwt_err() != OK) r = lmfs_rdwt_err(); /* check for disk error */
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if (lmfs_rdwt_err() == END_OF_FILE) r = OK;
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if (r != OK)
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return r;
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@ -124,7 +118,7 @@ int *completed; /* number of bytes copied */
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{
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/* Read or write (part of) a block. */
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register struct buf *bp = NULL;
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struct buf *bp = NULL;
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register int r = OK;
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int n;
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block_t b;
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@ -173,7 +167,8 @@ int *completed; /* number of bytes copied */
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n = NO_READ;
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assert(ino != VMC_NO_INODE);
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assert(!(ino_off % block_size));
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bp = lmfs_get_block_ino(dev, b, n, ino, ino_off);
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if ((r = lmfs_get_block_ino(&bp, dev, b, n, ino, ino_off)) != OK)
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panic("ext2: error getting block (%llu,%u): %d", dev, b, r);
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}
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/* In all cases, bp now points to a valid buffer. */
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@ -291,13 +286,19 @@ int opportunistic;
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struct buf *get_block_map(register struct inode *rip, u64_t position)
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{
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struct buf *bp;
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int r, block_size;
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block_t b = read_map(rip, position, 0); /* get block number */
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int block_size = get_block_size(rip->i_dev);
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if(b == NO_BLOCK)
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return NULL;
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block_size = get_block_size(rip->i_dev);
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position = rounddown(position, block_size);
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assert(rip->i_num != VMC_NO_INODE);
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return lmfs_get_block_ino(rip->i_dev, b, NORMAL, rip->i_num, position);
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if ((r = lmfs_get_block_ino(&bp, rip->i_dev, b, NORMAL, rip->i_num,
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position)) != OK)
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panic("ext2: error getting block (%llu,%u): %d",
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rip->i_dev, b, r);
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return bp;
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}
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/*===========================================================================*
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@ -333,7 +334,7 @@ unsigned bytes_ahead; /* bytes beyond position for immediate use */
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/* Minimum number of blocks to prefetch. */
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# define BLOCKS_MINIMUM (nr_bufs < 50 ? 18 : 32)
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int nr_bufs = lmfs_nr_bufs();
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int read_q_size;
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int r, read_q_size;
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unsigned int blocks_ahead, fragment, block_size;
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block_t block, blocks_left;
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off_t ind1_pos;
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@ -371,7 +372,9 @@ unsigned bytes_ahead; /* bytes beyond position for immediate use */
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bytes_ahead += fragment;
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blocks_ahead = (bytes_ahead + block_size - 1) / block_size;
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bp = lmfs_get_block_ino(dev, block, PREFETCH, rip->i_num, position);
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r = lmfs_get_block_ino(&bp, dev, block, PREFETCH, rip->i_num, position);
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if (r != OK)
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panic("ext2: error getting block (%llu,%u): %d", dev, block, r);
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assert(bp != NULL);
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if (lmfs_dev(bp) != NO_DEV) return(bp);
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@ -432,8 +435,11 @@ unsigned bytes_ahead; /* bytes beyond position for immediate use */
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thisblock = read_map(rip, (off_t) ex64lo(position_running), 1);
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if (thisblock != NO_BLOCK) {
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bp = lmfs_get_block_ino(dev, thisblock, PREFETCH, rip->i_num,
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position_running);
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r = lmfs_get_block_ino(&bp, dev, thisblock, PREFETCH,
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rip->i_num, position_running);
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if (r != OK)
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panic("ext2: error getting block (%llu,%u): %d",
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dev, thisblock, r);
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} else {
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bp = get_block(dev, block, PREFETCH);
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}
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@ -445,7 +451,10 @@ unsigned bytes_ahead; /* bytes beyond position for immediate use */
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}
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lmfs_rw_scattered(dev, read_q, read_q_size, READING);
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return(lmfs_get_block_ino(dev, baseblock, NORMAL, rip->i_num, position));
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r = lmfs_get_block_ino(&bp, dev, baseblock, NORMAL, rip->i_num, position);
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if (r != OK)
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panic("ext2: error getting block (%llu,%u): %d", dev, baseblock, r);
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return bp;
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}
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@ -8,6 +8,28 @@
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#include "super.h"
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/*===========================================================================*
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* get_block *
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*===========================================================================*/
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struct buf *get_block(dev_t dev, block_t block, int how)
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{
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/* Wrapper routine for lmfs_get_block(). This ext2 implementation does not deal
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* well with block read errors pretty much anywhere. To prevent corruption due
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* to unchecked error conditions, we panic upon an I/O failure here.
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*/
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struct buf *bp;
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int r;
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if ((r = lmfs_get_block(&bp, dev, block, how)) != OK && r != ENOENT)
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panic("ext2: error getting block (%llu,%u): %d", dev, block, r);
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assert(r == OK || how == PEEK);
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return (r == OK) ? bp : NULL;
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}
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/*===========================================================================*
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* conv2 *
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*===========================================================================*/
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@ -307,7 +307,7 @@ register struct inode *rip; /* pointer to inode */
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off_t position; /* file pointer */
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{
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/* Acquire a new block and return a pointer to it. */
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register struct buf *bp;
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struct buf *bp;
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int r;
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block_t b;
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@ -355,8 +355,10 @@ off_t position; /* file pointer */
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}
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}
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bp = lmfs_get_block_ino(rip->i_dev, b, NO_READ, rip->i_num,
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rounddown(position, rip->i_sp->s_block_size));
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r = lmfs_get_block_ino(&bp, rip->i_dev, b, NO_READ, rip->i_num,
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rounddown(position, rip->i_sp->s_block_size));
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if (r != OK)
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panic("ext2: error getting block (%llu,%u): %d", rip->i_dev, b, r);
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zero_block(bp);
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return(bp);
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}
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@ -26,7 +26,6 @@ ssize_t fs_read(ino_t ino_nr, struct fsdriver_data *data, size_t bytes,
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block_size = v_pri.logical_block_size_l;
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cum_io = 0;
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lmfs_reset_rdwt_err();
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r = OK;
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/* Split the transfer into chunks that don't span two blocks. */
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@ -47,8 +46,6 @@ ssize_t fs_read(ino_t ino_nr, struct fsdriver_data *data, size_t bytes,
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lmfs_put_block(bp);
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if (r != OK)
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break; /* EOF reached. */
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if (lmfs_rdwt_err() < 0)
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break;
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/* Update counters and pointers. */
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@ -57,11 +54,6 @@ ssize_t fs_read(ino_t ino_nr, struct fsdriver_data *data, size_t bytes,
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pos += chunk; /* Position within the file. */
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}
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if (lmfs_rdwt_err() != OK)
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r = lmfs_rdwt_err(); /* Check for disk error. */
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if (lmfs_rdwt_err() == END_OF_FILE)
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r = OK;
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return (r == OK) ? cum_io : r;
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}
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@ -12,11 +12,11 @@ int parse_susp(struct rrii_dir_record *dir, char *buffer)
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char susp_signature[2];
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u8_t susp_length;
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u8_t susp_version;
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u32_t ca_block_nr;
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u32_t ca_offset;
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u32_t ca_length;
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struct buf *ca_bp;
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int r;
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susp_signature[0] = buffer[0];
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susp_signature[1] = buffer[1];
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@ -44,10 +44,9 @@ int parse_susp(struct rrii_dir_record *dir, char *buffer)
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ca_length = v_pri.logical_block_size_l - ca_offset;
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}
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ca_bp = lmfs_get_block(fs_dev, ca_block_nr, NORMAL);
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if (ca_bp == NULL) {
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return EINVAL;
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}
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r = lmfs_get_block(&ca_bp, fs_dev, ca_block_nr, NORMAL);
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if (r != OK)
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return r;
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parse_susp_buffer(dir, b_data(ca_bp) + ca_offset, ca_length);
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lmfs_put_block(ca_bp);
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@ -36,12 +36,21 @@ void free_extent(struct dir_extent *e)
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struct buf* read_extent_block(struct dir_extent *e, size_t block)
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{
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size_t block_id = get_extent_absolute_block_id(e, block);
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struct buf *bp;
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size_t block_id;
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int r;
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block_id = get_extent_absolute_block_id(e, block);
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if (block_id == 0 || block_id >= v_pri.volume_space_size_l)
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return NULL;
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return lmfs_get_block(fs_dev, block_id, NORMAL);
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/* Not all callers deal well with failure, so panic on I/O error. */
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if ((r = lmfs_get_block(&bp, fs_dev, block_id, NORMAL)) != OK)
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panic("ISOFS: error getting block (%llu,%zu): %d",
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fs_dev, block_id, r);
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return bp;
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}
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size_t get_extent_absolute_block_id(struct dir_extent *e, size_t block)
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@ -1,17 +1,7 @@
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/* The file system maintains a buffer cache to reduce the number of disk
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* accesses needed. Whenever a read or write to the disk is done, a check is
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* first made to see if the block is in the cache. This file manages the
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* cache.
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*
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* The entry points into this file are:
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* get_block: request to fetch a block for reading or writing from cache
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* put_block: return a block previously requested with get_block
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* alloc_zone: allocate a new zone (to increase the length of a file)
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* free_zone: release a zone (when a file is removed)
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* invalidate: remove all the cache blocks on some device
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*
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* Private functions:
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* read_block: read or write a block from the disk itself
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* first made to see if the block is in the cache. This file contains some
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* related routines, but the cache is now in libminixfs.
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*/
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#include "fs.h"
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@ -26,6 +16,26 @@
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#include "super.h"
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#include "inode.h"
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/*===========================================================================*
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* get_block *
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*===========================================================================*/
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struct buf *get_block(dev_t dev, block_t block, int how)
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{
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/* Wrapper routine for lmfs_get_block(). This MFS implementation does not deal
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* well with block read errors pretty much anywhere. To prevent corruption due
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* to unchecked error conditions, we panic upon an I/O failure here.
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*/
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struct buf *bp;
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int r;
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if ((r = lmfs_get_block(&bp, dev, block, how)) != OK && r != ENOENT)
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panic("MFS: error getting block (%llu,%u): %d", dev, block, r);
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assert(r == OK || how == PEEK);
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return (r == OK) ? bp : NULL;
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}
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/*===========================================================================*
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* alloc_zone *
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*===========================================================================*/
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@ -2,7 +2,6 @@
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#define __MFS_PROTO_H__
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/* Some shortcuts to functions in -lminixfs */
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#define get_block(d, b, t) lmfs_get_block(d, b, t)
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#define put_block(b) lmfs_put_block(b)
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/* Function prototypes. */
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@ -16,6 +15,7 @@ struct super_block;
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/* cache.c */
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zone_t alloc_zone(dev_t dev, zone_t z);
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void free_zone(dev_t dev, zone_t numb);
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struct buf *get_block(dev_t dev, block_t block, int how);
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/* inode.c */
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struct inode *alloc_inode(dev_t dev, mode_t bits, uid_t uid, gid_t gid);
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@ -44,8 +44,6 @@ ssize_t fs_readwrite(ino_t ino_nr, struct fsdriver_data *data, size_t nrbytes,
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block_size = rip->i_sp->s_block_size;
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f_size = rip->i_size;
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lmfs_reset_rdwt_err();
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/* If this is file i/o, check we can write */
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if (call == FSC_WRITE) {
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if(rip->i_sp->s_rd_only)
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@ -80,8 +78,7 @@ ssize_t fs_readwrite(ino_t ino_nr, struct fsdriver_data *data, size_t nrbytes,
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r = rw_chunk(rip, ((u64_t)((unsigned long)position)), off, chunk,
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nrbytes, call, data, cum_io, block_size, &completed);
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if (r != OK) break; /* EOF reached */
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if (lmfs_rdwt_err() < 0) break;
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if (r != OK) break;
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/* Update counters and pointers. */
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nrbytes -= chunk; /* bytes yet to be read */
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@ -98,9 +95,6 @@ ssize_t fs_readwrite(ino_t ino_nr, struct fsdriver_data *data, size_t nrbytes,
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rip->i_seek = NO_SEEK;
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if (lmfs_rdwt_err() != OK) r = lmfs_rdwt_err(); /* check for disk error */
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if (lmfs_rdwt_err() == END_OF_FILE) r = OK;
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if (r != OK)
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return r;
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@ -134,8 +128,7 @@ unsigned int block_size; /* block size of FS operating on */
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int *completed; /* number of bytes copied */
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{
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/* Read or write (part of) a block. */
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register struct buf *bp = NULL;
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struct buf *bp = NULL;
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register int r = OK;
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int n;
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block_t b;
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@ -184,7 +177,8 @@ int *completed; /* number of bytes copied */
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n = NO_READ;
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assert(ino != VMC_NO_INODE);
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assert(!(ino_off % block_size));
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bp = lmfs_get_block_ino(dev, b, n, ino, ino_off);
|
||||
if ((r = lmfs_get_block_ino(&bp, dev, b, n, ino, ino_off)) != OK)
|
||||
panic("MFS: error getting block (%llu,%u): %d", dev, b, r);
|
||||
}
|
||||
|
||||
/* In all cases, bp now points to a valid buffer. */
|
||||
|
|
@ -288,13 +282,19 @@ int opportunistic; /* if nonzero, only use cache for metadata */
|
|||
|
||||
struct buf *get_block_map(register struct inode *rip, u64_t position)
|
||||
{
|
||||
struct buf *bp;
|
||||
int r, block_size;
|
||||
block_t b = read_map(rip, position, 0); /* get block number */
|
||||
int block_size = get_block_size(rip->i_dev);
|
||||
if(b == NO_BLOCK)
|
||||
return NULL;
|
||||
block_size = get_block_size(rip->i_dev);
|
||||
position = rounddown(position, block_size);
|
||||
assert(rip->i_num != VMC_NO_INODE);
|
||||
return lmfs_get_block_ino(rip->i_dev, b, NORMAL, rip->i_num, position);
|
||||
if ((r = lmfs_get_block_ino(&bp, rip->i_dev, b, NORMAL, rip->i_num,
|
||||
position)) != OK)
|
||||
panic("MFS: error getting block (%llu,%u): %d",
|
||||
rip->i_dev, b, r);
|
||||
return bp;
|
||||
}
|
||||
|
||||
/*===========================================================================*
|
||||
|
|
@ -345,7 +345,7 @@ unsigned bytes_ahead; /* bytes beyond position for immediate use */
|
|||
/* Minimum number of blocks to prefetch. */
|
||||
int nr_bufs = lmfs_nr_bufs();
|
||||
# define BLOCKS_MINIMUM (nr_bufs < 50 ? 18 : 32)
|
||||
int scale, read_q_size;
|
||||
int r, scale, read_q_size;
|
||||
unsigned int blocks_ahead, fragment, block_size;
|
||||
block_t block, blocks_left;
|
||||
off_t ind1_pos;
|
||||
|
|
@ -379,7 +379,9 @@ unsigned bytes_ahead; /* bytes beyond position for immediate use */
|
|||
bytes_ahead += fragment;
|
||||
blocks_ahead = (bytes_ahead + block_size - 1) / block_size;
|
||||
|
||||
bp = lmfs_get_block_ino(dev, block, PREFETCH, rip->i_num, position);
|
||||
r = lmfs_get_block_ino(&bp, dev, block, PREFETCH, rip->i_num, position);
|
||||
if (r != OK)
|
||||
panic("MFS: error getting block (%llu,%u): %d", dev, block, r);
|
||||
assert(bp != NULL);
|
||||
assert(bp->lmfs_count > 0);
|
||||
if (lmfs_dev(bp) != NO_DEV) return(bp);
|
||||
|
|
@ -443,8 +445,11 @@ unsigned bytes_ahead; /* bytes beyond position for immediate use */
|
|||
|
||||
thisblock = read_map(rip, (off_t) ex64lo(position_running), 1);
|
||||
if (thisblock != NO_BLOCK) {
|
||||
bp = lmfs_get_block_ino(dev, thisblock, PREFETCH, rip->i_num,
|
||||
position_running);
|
||||
r = lmfs_get_block_ino(&bp, dev, thisblock, PREFETCH,
|
||||
rip->i_num, position_running);
|
||||
if (r != OK)
|
||||
panic("MFS: error getting block (%llu,%u): %d",
|
||||
dev, thisblock, r);
|
||||
} else {
|
||||
bp = get_block(dev, block, PREFETCH);
|
||||
}
|
||||
|
|
@ -460,7 +465,10 @@ unsigned bytes_ahead; /* bytes beyond position for immediate use */
|
|||
|
||||
assert(inuse_before == lmfs_bufs_in_use());
|
||||
|
||||
return(lmfs_get_block_ino(dev, baseblock, NORMAL, rip->i_num, position));
|
||||
r = lmfs_get_block_ino(&bp, dev, baseblock, NORMAL, rip->i_num, position);
|
||||
if (r != OK)
|
||||
panic("MFS: error getting block (%llu,%u): %d", dev, baseblock, r);
|
||||
return bp;
|
||||
}
|
||||
|
||||
|
||||
|
|
|
|||
|
|
@ -259,8 +259,7 @@ off_t position; /* file pointer */
|
|||
* allocating a complete zone, and then returning the initial block.
|
||||
* On the other hand, the current zone may still have some unused blocks.
|
||||
*/
|
||||
|
||||
register struct buf *bp;
|
||||
struct buf *bp;
|
||||
block_t b, base_block;
|
||||
zone_t z;
|
||||
zone_t zone_size;
|
||||
|
|
@ -297,8 +296,10 @@ off_t position; /* file pointer */
|
|||
b = base_block + (block_t)((position % zone_size)/rip->i_sp->s_block_size);
|
||||
}
|
||||
|
||||
bp = lmfs_get_block_ino(rip->i_dev, b, NO_READ, rip->i_num,
|
||||
r = lmfs_get_block_ino(&bp, rip->i_dev, b, NO_READ, rip->i_num,
|
||||
rounddown(position, rip->i_sp->s_block_size));
|
||||
if (r != OK)
|
||||
panic("MFS: error getting block (%llu,%u): %d", rip->i_dev, b, r);
|
||||
zero_block(bp);
|
||||
return(bp);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -17,7 +17,7 @@ struct buf {
|
|||
block64_t lmfs_blocknr; /* block number of its (minor) device */
|
||||
char lmfs_count; /* number of users of this buffer */
|
||||
char lmfs_needsetcache; /* to be identified to VM */
|
||||
unsigned int lmfs_bytes; /* Number of bytes allocated in bp */
|
||||
size_t lmfs_bytes; /* size of this block (allocated and used) */
|
||||
u32_t lmfs_flags; /* Flags shared between VM and FS */
|
||||
|
||||
/* If any, which inode & offset does this block correspond to?
|
||||
|
|
@ -38,12 +38,10 @@ void lmfs_flushdev(dev_t dev);
|
|||
size_t lmfs_fs_block_size(void);
|
||||
void lmfs_may_use_vmcache(int);
|
||||
void lmfs_set_blocksize(size_t blocksize);
|
||||
void lmfs_reset_rdwt_err(void);
|
||||
int lmfs_rdwt_err(void);
|
||||
void lmfs_buf_pool(int new_nr_bufs);
|
||||
struct buf *lmfs_get_block(dev_t dev, block64_t block, int how);
|
||||
struct buf *lmfs_get_block_ino(dev_t dev, block64_t block, int how, ino_t ino,
|
||||
u64_t off);
|
||||
int lmfs_get_block(struct buf **bpp, dev_t dev, block64_t block, int how);
|
||||
int lmfs_get_block_ino(struct buf **bpp, dev_t dev, block64_t block, int how,
|
||||
ino_t ino, u64_t off);
|
||||
void lmfs_put_block(struct buf *bp);
|
||||
void lmfs_free_block(dev_t dev, block64_t block);
|
||||
void lmfs_zero_block_ino(dev_t dev, ino_t ino, u64_t off);
|
||||
|
|
@ -57,9 +55,7 @@ void lmfs_change_blockusage(int delta);
|
|||
#define NORMAL 0 /* forces get_block to do disk read */
|
||||
#define NO_READ 1 /* prevents get_block from doing disk read */
|
||||
#define PREFETCH 2 /* tells get_block not to read or mark dev */
|
||||
#define PEEK 3 /* returns NULL if not in cache or VM cache */
|
||||
|
||||
#define END_OF_FILE (-104) /* eof detected */
|
||||
#define PEEK 3 /* returns ENOENT if not in cache */
|
||||
|
||||
/* Block I/O helper functions. */
|
||||
void lmfs_driver(dev_t dev, char *label);
|
||||
|
|
|
|||
|
|
@ -32,8 +32,12 @@
|
|||
#include <minix/libminixfs.h>
|
||||
#include <minix/fsdriver.h>
|
||||
#include <minix/bdev.h>
|
||||
#include <minix/partition.h>
|
||||
#include <sys/ioctl.h>
|
||||
#include <assert.h>
|
||||
|
||||
#include "inc.h"
|
||||
|
||||
/*
|
||||
* Set the driver label of the device identified by 'dev' to 'label'. While
|
||||
* 'dev' is a full device number, only its major device number is to be used.
|
||||
|
|
@ -49,6 +53,7 @@ lmfs_driver(dev_t dev, char *label)
|
|||
|
||||
/*
|
||||
* Prefetch up to "nblocks" blocks on "dev" starting from block number "block".
|
||||
* The size to be used for the last block in the range is given as "last_size".
|
||||
* Stop early when either the I/O request fills up or when a block is already
|
||||
* found to be in the cache. The latter is likely to happen often, since this
|
||||
* function is called before getting each block for reading. Prefetching is a
|
||||
|
|
@ -56,14 +61,28 @@ lmfs_driver(dev_t dev, char *label)
|
|||
* TODO: limit according to the number of available buffers.
|
||||
*/
|
||||
static void
|
||||
block_prefetch(dev_t dev, block64_t block, unsigned int nblocks)
|
||||
block_prefetch(dev_t dev, block64_t block, unsigned int nblocks,
|
||||
size_t block_size, size_t last_size)
|
||||
{
|
||||
struct buf *bp, *bufs[NR_IOREQS];
|
||||
unsigned int count;
|
||||
int r;
|
||||
|
||||
if (nblocks > NR_IOREQS) {
|
||||
nblocks = NR_IOREQS;
|
||||
|
||||
last_size = block_size;
|
||||
}
|
||||
|
||||
for (count = 0; count < nblocks; count++) {
|
||||
bp = lmfs_get_block(dev, block + count, PREFETCH);
|
||||
assert(bp != NULL);
|
||||
if (count == nblocks - 1 && last_size < block_size)
|
||||
r = lmfs_get_partial_block(&bp, dev, block + count,
|
||||
PREFETCH, last_size);
|
||||
else
|
||||
r = lmfs_get_block(&bp, dev, block + count, PREFETCH);
|
||||
|
||||
if (r != OK)
|
||||
panic("libminixfs: get_block PREFETCH error: %d\n", r);
|
||||
|
||||
if (lmfs_dev(bp) != NO_DEV) {
|
||||
lmfs_put_block(bp);
|
||||
|
|
@ -90,21 +109,16 @@ block_prefetch(dev_t dev, block64_t block, unsigned int nblocks)
|
|||
* flushed immediately, and thus, a successful write only indicates that the
|
||||
* data have been taken in by the cache (for immediate I/O, a character device
|
||||
* would have to be used, but MINIX3 no longer supports this), which may be
|
||||
* follwed later by silent failures, including undetected end-of-file cases.
|
||||
* In particular, write requests may or may not return 0 (EOF) immediately when
|
||||
* writing at or beyond the block device's size. i Since block I/O takes place
|
||||
* at block granularity, block-unaligned writes have to read a block from disk
|
||||
* before updating it, and that is the only possible source of actual I/O
|
||||
* errors for write calls.
|
||||
* TODO: reconsider the buffering-only approach, or see if we can at least
|
||||
* somehow throw accurate EOF errors without reading in each block first.
|
||||
* follwed later by silent failures. End-of-file conditions are always
|
||||
* reported immediately, though.
|
||||
*/
|
||||
ssize_t
|
||||
lmfs_bio(dev_t dev, struct fsdriver_data * data, size_t bytes, off_t pos,
|
||||
int call)
|
||||
{
|
||||
block64_t block;
|
||||
size_t block_size, off, block_off, chunk;
|
||||
struct part_geom part;
|
||||
size_t block_size, off, block_off, last_size, size, chunk;
|
||||
unsigned int blocks_left;
|
||||
struct buf *bp;
|
||||
int r, write, how;
|
||||
|
|
@ -123,37 +137,74 @@ lmfs_bio(dev_t dev, struct fsdriver_data * data, size_t bytes, off_t pos,
|
|||
if (pos < 0 || bytes > SSIZE_MAX || pos > INT64_MAX - bytes + 1)
|
||||
return EINVAL;
|
||||
|
||||
/*
|
||||
* Get the partition size, so that we can handle EOF ourselves.
|
||||
* Unfortunately, we cannot cache the results between calls, since we
|
||||
* do not get to see DIOCSETP ioctls--see also repartition(8).
|
||||
*/
|
||||
if ((r = bdev_ioctl(dev, DIOCGETP, &part, NONE /*user_endpt*/)) != OK)
|
||||
return r;
|
||||
|
||||
if ((uint64_t)pos >= part.size)
|
||||
return 0; /* EOF */
|
||||
|
||||
if ((uint64_t)pos > part.size - bytes)
|
||||
bytes = part.size - pos;
|
||||
|
||||
off = 0;
|
||||
block = pos / block_size;
|
||||
block_off = (size_t)(pos % block_size);
|
||||
blocks_left = howmany(block_off + bytes, block_size);
|
||||
|
||||
lmfs_reset_rdwt_err();
|
||||
assert(blocks_left > 0);
|
||||
|
||||
/*
|
||||
* If the last block we need is also the last block of the device,
|
||||
* see how many bytes we should actually transfer for that block.
|
||||
*/
|
||||
if (block + blocks_left - 1 == part.size / block_size)
|
||||
last_size = part.size % block_size;
|
||||
else
|
||||
last_size = block_size;
|
||||
|
||||
r = OK;
|
||||
|
||||
for (off = 0; off < bytes; off += chunk) {
|
||||
chunk = block_size - block_off;
|
||||
for (off = 0; off < bytes && blocks_left > 0; off += chunk) {
|
||||
size = (blocks_left == 1) ? last_size : block_size;
|
||||
|
||||
chunk = size - block_off;
|
||||
if (chunk > bytes - off)
|
||||
chunk = bytes - off;
|
||||
|
||||
assert(chunk > 0 && chunk <= size);
|
||||
|
||||
/*
|
||||
* For read requests, help the block driver form larger I/O
|
||||
* requests.
|
||||
*/
|
||||
if (!write)
|
||||
block_prefetch(dev, block, blocks_left);
|
||||
block_prefetch(dev, block, blocks_left, block_size,
|
||||
last_size);
|
||||
|
||||
/*
|
||||
* Do not read the block from disk if we will end up
|
||||
* overwriting all of its contents.
|
||||
*/
|
||||
how = (write && chunk == block_size) ? NO_READ : NORMAL;
|
||||
how = (write && chunk == size) ? NO_READ : NORMAL;
|
||||
|
||||
bp = lmfs_get_block(dev, block, how);
|
||||
assert(bp);
|
||||
if (size < block_size)
|
||||
r = lmfs_get_partial_block(&bp, dev, block, how, size);
|
||||
else
|
||||
r = lmfs_get_block(&bp, dev, block, how);
|
||||
|
||||
r = lmfs_rdwt_err();
|
||||
if (r != OK) {
|
||||
printf("libminixfs: error getting block <%"PRIx64","
|
||||
"%"PRIu64"> for device I/O (%d)\n", dev, block, r);
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
/* Perform the actual copy. */
|
||||
if (r == OK && data != NULL) {
|
||||
assert(lmfs_dev(bp) != NO_DEV);
|
||||
|
||||
|
|
@ -186,12 +237,11 @@ lmfs_bio(dev_t dev, struct fsdriver_data * data, size_t bytes, off_t pos,
|
|||
}
|
||||
|
||||
/*
|
||||
* If we were not able to do any I/O, return the error (or EOF, even
|
||||
* for writes). Otherwise, return how many bytes we did manage to
|
||||
* transfer.
|
||||
* If we were not able to do any I/O, return the error. Otherwise,
|
||||
* return how many bytes we did manage to transfer.
|
||||
*/
|
||||
if (r != OK && off == 0)
|
||||
return (r == END_OF_FILE) ? 0 : r;
|
||||
return r;
|
||||
|
||||
return off;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -2,6 +2,7 @@
|
|||
#define _SYSTEM
|
||||
|
||||
#include <assert.h>
|
||||
#include <string.h>
|
||||
#include <errno.h>
|
||||
#include <math.h>
|
||||
#include <stdlib.h>
|
||||
|
|
@ -18,6 +19,8 @@
|
|||
#include <minix/u64.h>
|
||||
#include <minix/bdev.h>
|
||||
|
||||
#include "inc.h"
|
||||
|
||||
/* Buffer (block) cache. To acquire a block, a routine calls lmfs_get_block(),
|
||||
* telling which block it wants. The block is then regarded as "in use" and
|
||||
* has its reference count incremented. All the blocks that are not in use are
|
||||
|
|
@ -44,7 +47,7 @@ static struct buf *rear; /* points to most recently used free block */
|
|||
static unsigned int bufs_in_use;/* # bufs currently in use (not on free list)*/
|
||||
|
||||
static void rm_lru(struct buf *bp);
|
||||
static void read_block(struct buf *);
|
||||
static int read_block(struct buf *bp, size_t size);
|
||||
static void freeblock(struct buf *bp);
|
||||
static void cache_heuristic_check(void);
|
||||
static void put_block(struct buf *bp, int put_flags);
|
||||
|
|
@ -60,8 +63,6 @@ static size_t fs_block_size = PAGE_SIZE; /* raw i/o block size */
|
|||
|
||||
static fsblkcnt_t fs_btotal = 0, fs_bused = 0;
|
||||
|
||||
static int rdwt_err;
|
||||
|
||||
static int quiet = 0;
|
||||
|
||||
void lmfs_setquiet(int q) { quiet = q; }
|
||||
|
|
@ -193,33 +194,33 @@ static void free_unused_blocks(void)
|
|||
printf("libminixfs: freeing; %d blocks, %d bytes\n", freed, bytes);
|
||||
}
|
||||
|
||||
static void lmfs_alloc_block(struct buf *bp)
|
||||
static void lmfs_alloc_block(struct buf *bp, size_t block_size)
|
||||
{
|
||||
int len;
|
||||
ASSERT(!bp->data);
|
||||
ASSERT(bp->lmfs_bytes == 0);
|
||||
|
||||
len = roundup(fs_block_size, PAGE_SIZE);
|
||||
len = roundup(block_size, PAGE_SIZE);
|
||||
|
||||
if((bp->data = mmap(0, fs_block_size,
|
||||
PROT_READ|PROT_WRITE, MAP_PREALLOC|MAP_ANON, -1, 0)) == MAP_FAILED) {
|
||||
if((bp->data = mmap(0, block_size, PROT_READ|PROT_WRITE,
|
||||
MAP_PREALLOC|MAP_ANON, -1, 0)) == MAP_FAILED) {
|
||||
free_unused_blocks();
|
||||
if((bp->data = mmap(0, fs_block_size, PROT_READ|PROT_WRITE,
|
||||
if((bp->data = mmap(0, block_size, PROT_READ|PROT_WRITE,
|
||||
MAP_PREALLOC|MAP_ANON, -1, 0)) == MAP_FAILED) {
|
||||
panic("libminixfs: could not allocate block");
|
||||
}
|
||||
}
|
||||
assert(bp->data);
|
||||
bp->lmfs_bytes = fs_block_size;
|
||||
bp->lmfs_bytes = block_size;
|
||||
bp->lmfs_needsetcache = 1;
|
||||
}
|
||||
|
||||
/*===========================================================================*
|
||||
* lmfs_get_block *
|
||||
*===========================================================================*/
|
||||
struct buf *lmfs_get_block(dev_t dev, block64_t block, int how)
|
||||
int lmfs_get_block(struct buf **bpp, dev_t dev, block64_t block, int how)
|
||||
{
|
||||
return lmfs_get_block_ino(dev, block, how, VMC_NO_INODE, 0);
|
||||
return lmfs_get_block_ino(bpp, dev, block, how, VMC_NO_INODE, 0);
|
||||
}
|
||||
|
||||
static void munmap_t(void *a, int len)
|
||||
|
|
@ -264,7 +265,7 @@ static void freeblock(struct buf *bp)
|
|||
*/
|
||||
if (bp->lmfs_dev != NO_DEV) {
|
||||
if (!lmfs_isclean(bp)) lmfs_flushdev(bp->lmfs_dev);
|
||||
assert(bp->lmfs_bytes == fs_block_size);
|
||||
assert(bp->lmfs_bytes > 0);
|
||||
bp->lmfs_dev = NO_DEV;
|
||||
}
|
||||
|
||||
|
|
@ -300,27 +301,32 @@ static struct buf *find_block(dev_t dev, block64_t block)
|
|||
}
|
||||
|
||||
/*===========================================================================*
|
||||
* lmfs_get_block_ino *
|
||||
* get_block_ino *
|
||||
*===========================================================================*/
|
||||
struct buf *lmfs_get_block_ino(dev_t dev, block64_t block, int how, ino_t ino,
|
||||
u64_t ino_off)
|
||||
static int get_block_ino(struct buf **bpp, dev_t dev, block64_t block, int how,
|
||||
ino_t ino, u64_t ino_off, size_t block_size)
|
||||
{
|
||||
/* Check to see if the requested block is in the block cache. If so, return
|
||||
* a pointer to it. If not, evict some other block and fetch it (unless
|
||||
* 'how' is NO_READ). All the blocks in the cache that are not in use are
|
||||
* linked together in a chain, with 'front' pointing to the least recently used
|
||||
* block and 'rear' to the most recently used block. If 'how' is NO_READ, the
|
||||
* block being requested will be overwritten in its entirety, so it is only
|
||||
* necessary to see if it is in the cache; if it is not, any free buffer will
|
||||
* do. It is not necessary to actually read the block in from disk. If 'how'
|
||||
/* Check to see if the requested block is in the block cache. The requested
|
||||
* block is identified by the block number in 'block' on device 'dev', counted
|
||||
* in the file system block size. The amount of data requested for this block
|
||||
* is given in 'block_size', which may be less than the file system block size
|
||||
* iff the requested block is the last (partial) block on a device. Note that
|
||||
* the given block size does *not* affect the conversion of 'block' to a byte
|
||||
* offset! Either way, if the block could be obtained, either from the cache
|
||||
* or by reading from the device, return OK, with a pointer to the buffer
|
||||
* structure stored in 'bpp'. If not, return a negative error code (and no
|
||||
* buffer). If necessary, evict some other block and fetch the contents from
|
||||
* disk (if 'how' is NORMAL). If 'how' is NO_READ, the caller intends to
|
||||
* overwrite the requested block in its entirety, so it is only necessary to
|
||||
* see if it is in the cache; if it is not, any free buffer will do. If 'how'
|
||||
* is PREFETCH, the block need not be read from the disk, and the device is not
|
||||
* to be marked on the block (i.e., set to NO_DEV), so callers can tell if the
|
||||
* block returned is valid. If 'how' is PEEK, the function returns the block
|
||||
* if it is in the cache or could be obtained from VM, and NULL otherwise.
|
||||
* if it is in the cache or the VM cache, and an ENOENT error code otherwise.
|
||||
* In addition to the LRU chain, there is also a hash chain to link together
|
||||
* blocks whose block numbers end with the same bit strings, for fast lookup.
|
||||
*/
|
||||
int b;
|
||||
int b, r;
|
||||
static struct buf *bp;
|
||||
uint64_t dev_off;
|
||||
struct buf *prev_ptr;
|
||||
|
|
@ -347,6 +353,13 @@ struct buf *lmfs_get_block_ino(dev_t dev, block64_t block, int how, ino_t ino,
|
|||
/* See if the block is in the cache. If so, we can return it right away. */
|
||||
bp = find_block(dev, block);
|
||||
if (bp != NULL && !(bp->lmfs_flags & VMMC_EVICTED)) {
|
||||
ASSERT(bp->lmfs_dev == dev);
|
||||
ASSERT(bp->lmfs_dev != NO_DEV);
|
||||
|
||||
/* The block must have exactly the requested number of bytes. */
|
||||
if (bp->lmfs_bytes != block_size)
|
||||
return EIO;
|
||||
|
||||
/* Block needed has been found. */
|
||||
if (bp->lmfs_count == 0) {
|
||||
rm_lru(bp);
|
||||
|
|
@ -356,9 +369,6 @@ struct buf *lmfs_get_block_ino(dev_t dev, block64_t block, int how, ino_t ino,
|
|||
bp->lmfs_flags |= VMMC_BLOCK_LOCKED;
|
||||
}
|
||||
raisecount(bp);
|
||||
ASSERT(bp->lmfs_bytes == fs_block_size);
|
||||
ASSERT(bp->lmfs_dev == dev);
|
||||
ASSERT(bp->lmfs_dev != NO_DEV);
|
||||
ASSERT(bp->lmfs_flags & VMMC_BLOCK_LOCKED);
|
||||
ASSERT(bp->data);
|
||||
|
||||
|
|
@ -372,7 +382,8 @@ struct buf *lmfs_get_block_ino(dev_t dev, block64_t block, int how, ino_t ino,
|
|||
}
|
||||
}
|
||||
|
||||
return(bp);
|
||||
*bpp = bp;
|
||||
return OK;
|
||||
}
|
||||
|
||||
/* We had the block in the cache but VM evicted it; invalidate it. */
|
||||
|
|
@ -437,10 +448,11 @@ struct buf *lmfs_get_block_ino(dev_t dev, block64_t block, int how, ino_t ino,
|
|||
assert(!bp->lmfs_bytes);
|
||||
if(vmcache) {
|
||||
if((bp->data = vm_map_cacheblock(dev, dev_off, ino, ino_off,
|
||||
&bp->lmfs_flags, fs_block_size)) != MAP_FAILED) {
|
||||
bp->lmfs_bytes = fs_block_size;
|
||||
&bp->lmfs_flags, roundup(block_size, PAGE_SIZE))) != MAP_FAILED) {
|
||||
bp->lmfs_bytes = block_size;
|
||||
ASSERT(!bp->lmfs_needsetcache);
|
||||
return bp;
|
||||
*bpp = bp;
|
||||
return OK;
|
||||
}
|
||||
}
|
||||
bp->data = NULL;
|
||||
|
|
@ -455,12 +467,12 @@ struct buf *lmfs_get_block_ino(dev_t dev, block64_t block, int how, ino_t ino,
|
|||
|
||||
put_block(bp, ONE_SHOT);
|
||||
|
||||
return NULL;
|
||||
return ENOENT;
|
||||
}
|
||||
|
||||
/* Not in the cache; reserve memory for its contents. */
|
||||
|
||||
lmfs_alloc_block(bp);
|
||||
lmfs_alloc_block(bp, block_size);
|
||||
|
||||
assert(bp->data);
|
||||
|
||||
|
|
@ -468,7 +480,12 @@ struct buf *lmfs_get_block_ino(dev_t dev, block64_t block, int how, ino_t ino,
|
|||
/* PREFETCH: don't do i/o. */
|
||||
bp->lmfs_dev = NO_DEV;
|
||||
} else if (how == NORMAL) {
|
||||
read_block(bp);
|
||||
/* Try to read the block. Return an error code on failure. */
|
||||
if ((r = read_block(bp, block_size)) != OK) {
|
||||
put_block(bp, 0);
|
||||
|
||||
return r;
|
||||
}
|
||||
} else if(how == NO_READ) {
|
||||
/* This block will be overwritten by new contents. */
|
||||
} else
|
||||
|
|
@ -476,7 +493,26 @@ struct buf *lmfs_get_block_ino(dev_t dev, block64_t block, int how, ino_t ino,
|
|||
|
||||
assert(bp->data);
|
||||
|
||||
return(bp); /* return the newly acquired block */
|
||||
*bpp = bp; /* return the newly acquired block */
|
||||
return OK;
|
||||
}
|
||||
|
||||
/*===========================================================================*
|
||||
* lmfs_get_block_ino *
|
||||
*===========================================================================*/
|
||||
int lmfs_get_block_ino(struct buf **bpp, dev_t dev, block64_t block, int how,
|
||||
ino_t ino, u64_t ino_off)
|
||||
{
|
||||
return get_block_ino(bpp, dev, block, how, ino, ino_off, fs_block_size);
|
||||
}
|
||||
|
||||
/*===========================================================================*
|
||||
* lmfs_get_partial_block *
|
||||
*===========================================================================*/
|
||||
int lmfs_get_partial_block(struct buf **bpp, dev_t dev, block64_t block,
|
||||
int how, size_t block_size)
|
||||
{
|
||||
return get_block_ino(bpp, dev, block, how, VMC_NO_INODE, 0, block_size);
|
||||
}
|
||||
|
||||
/*===========================================================================*
|
||||
|
|
@ -536,12 +572,21 @@ static void put_block(struct buf *bp, int put_flags)
|
|||
assert(bp->data);
|
||||
|
||||
setflags = (put_flags & ONE_SHOT) ? VMSF_ONCE : 0;
|
||||
|
||||
if ((r = vm_set_cacheblock(bp->data, dev, dev_off, bp->lmfs_inode,
|
||||
bp->lmfs_inode_offset, &bp->lmfs_flags, fs_block_size,
|
||||
setflags)) != OK) {
|
||||
bp->lmfs_inode_offset, &bp->lmfs_flags,
|
||||
roundup(bp->lmfs_bytes, PAGE_SIZE), setflags)) != OK) {
|
||||
if(r == ENOSYS) {
|
||||
printf("libminixfs: ENOSYS, disabling VM calls\n");
|
||||
vmcache = 0;
|
||||
} else if (r == ENOMEM) {
|
||||
/* Do not panic in this case. Running out of memory is
|
||||
* bad, especially since it may lead to applications
|
||||
* crashing when trying to access memory-mapped pages
|
||||
* we haven't been able to pass off to the VM cache,
|
||||
* but the entire file system crashing is always worse.
|
||||
*/
|
||||
printf("libminixfs: no memory for cache block!\n");
|
||||
} else {
|
||||
panic("libminixfs: setblock of %p dev 0x%llx off "
|
||||
"0x%llx failed\n", bp->data, dev, dev_off);
|
||||
|
|
@ -634,6 +679,7 @@ void lmfs_zero_block_ino(dev_t dev, ino_t ino, u64_t ino_off)
|
|||
*/
|
||||
struct buf *bp;
|
||||
static block64_t fake_block = 0;
|
||||
int r;
|
||||
|
||||
if (!vmcache)
|
||||
return;
|
||||
|
|
@ -650,7 +696,9 @@ void lmfs_zero_block_ino(dev_t dev, ino_t ino, u64_t ino_off)
|
|||
fake_block = ((uint64_t)INT64_MAX + 1) / fs_block_size;
|
||||
|
||||
/* Obtain a block. */
|
||||
bp = lmfs_get_block_ino(dev, fake_block, NO_READ, ino, ino_off);
|
||||
if ((r = lmfs_get_block_ino(&bp, dev, fake_block, NO_READ, ino,
|
||||
ino_off)) != OK)
|
||||
panic("libminixfs: getting a NO_READ block failed: %d", r);
|
||||
assert(bp != NULL);
|
||||
assert(bp->lmfs_dev != NO_DEV);
|
||||
|
||||
|
|
@ -684,33 +732,28 @@ void lmfs_set_blockusage(fsblkcnt_t btotal, fsblkcnt_t bused)
|
|||
/*===========================================================================*
|
||||
* read_block *
|
||||
*===========================================================================*/
|
||||
static void read_block(
|
||||
struct buf *bp /* buffer pointer */
|
||||
)
|
||||
static int read_block(struct buf *bp, size_t block_size)
|
||||
{
|
||||
/* Read or write a disk block. This is the only routine in which actual disk
|
||||
* I/O is invoked. If an error occurs, a message is printed here, but the error
|
||||
* is not reported to the caller. If the error occurred while purging a block
|
||||
* from the cache, it is not clear what the caller could do about it anyway.
|
||||
/* Read a disk block of 'size' bytes. The given size is always the FS block
|
||||
* size, except for the last block of a device. If an I/O error occurs,
|
||||
* invalidate the block and return an error code.
|
||||
*/
|
||||
int r, op_failed;
|
||||
ssize_t r;
|
||||
off_t pos;
|
||||
dev_t dev = bp->lmfs_dev;
|
||||
|
||||
op_failed = 0;
|
||||
|
||||
assert(dev != NO_DEV);
|
||||
|
||||
ASSERT(bp->lmfs_bytes == fs_block_size);
|
||||
ASSERT(bp->lmfs_bytes == block_size);
|
||||
ASSERT(fs_block_size > 0);
|
||||
|
||||
pos = (off_t)bp->lmfs_blocknr * fs_block_size;
|
||||
if(fs_block_size > PAGE_SIZE) {
|
||||
if (block_size > PAGE_SIZE) {
|
||||
#define MAXPAGES 20
|
||||
vir_bytes blockrem, vaddr = (vir_bytes) bp->data;
|
||||
int p = 0;
|
||||
static iovec_t iovec[MAXPAGES];
|
||||
blockrem = fs_block_size;
|
||||
blockrem = block_size;
|
||||
while(blockrem > 0) {
|
||||
vir_bytes chunk = blockrem >= PAGE_SIZE ? PAGE_SIZE : blockrem;
|
||||
iovec[p].iov_addr = vaddr;
|
||||
|
|
@ -721,25 +764,20 @@ static void read_block(
|
|||
}
|
||||
r = bdev_gather(dev, pos, iovec, p, BDEV_NOFLAGS);
|
||||
} else {
|
||||
r = bdev_read(dev, pos, bp->data, fs_block_size,
|
||||
BDEV_NOFLAGS);
|
||||
r = bdev_read(dev, pos, bp->data, block_size, BDEV_NOFLAGS);
|
||||
}
|
||||
if (r < 0) {
|
||||
printf("fs cache: I/O error on device %d/%d, block %"PRIu64"\n",
|
||||
major(dev), minor(dev), bp->lmfs_blocknr);
|
||||
op_failed = 1;
|
||||
} else if (r != (ssize_t) fs_block_size) {
|
||||
r = END_OF_FILE;
|
||||
op_failed = 1;
|
||||
}
|
||||
|
||||
if (op_failed) {
|
||||
bp->lmfs_dev = NO_DEV; /* invalidate block */
|
||||
|
||||
/* Report read errors to interested parties. */
|
||||
rdwt_err = r;
|
||||
if (r != (ssize_t)block_size) {
|
||||
printf("fs cache: I/O error on device %d/%d, block %"PRIu64" (%zd)\n",
|
||||
major(dev), minor(dev), bp->lmfs_blocknr, r);
|
||||
if (r >= 0)
|
||||
r = EIO; /* TODO: retry retrieving (just) the remaining part */
|
||||
|
||||
bp->lmfs_dev = NO_DEV; /* invalidate block */
|
||||
|
||||
return r;
|
||||
}
|
||||
|
||||
return OK;
|
||||
}
|
||||
|
||||
/*===========================================================================*
|
||||
|
|
@ -842,13 +880,12 @@ void lmfs_rw_scattered(
|
|||
}
|
||||
|
||||
/* therefore they are all 'in use' and must be at least this many */
|
||||
assert(start_in_use >= start_bufqsize);
|
||||
assert(start_in_use >= start_bufqsize);
|
||||
}
|
||||
|
||||
assert(dev != NO_DEV);
|
||||
assert(fs_block_size > 0);
|
||||
iov_per_block = roundup(fs_block_size, PAGE_SIZE) / PAGE_SIZE;
|
||||
assert(iov_per_block < NR_IOREQS);
|
||||
assert(howmany(fs_block_size, PAGE_SIZE) <= NR_IOREQS);
|
||||
|
||||
/* (Shell) sort buffers on lmfs_blocknr. */
|
||||
gap = 1;
|
||||
|
|
@ -881,11 +918,13 @@ void lmfs_rw_scattered(
|
|||
bp = bufq[nblocks];
|
||||
if (bp->lmfs_blocknr != bufq[0]->lmfs_blocknr + nblocks)
|
||||
break;
|
||||
blockrem = bp->lmfs_bytes;
|
||||
iov_per_block = howmany(blockrem, PAGE_SIZE);
|
||||
if(niovecs >= NR_IOREQS-iov_per_block) break;
|
||||
vdata = (vir_bytes) bp->data;
|
||||
blockrem = fs_block_size;
|
||||
for(p = 0; p < iov_per_block; p++) {
|
||||
vir_bytes chunk = blockrem < PAGE_SIZE ? blockrem : PAGE_SIZE;
|
||||
vir_bytes chunk =
|
||||
blockrem < PAGE_SIZE ? blockrem : PAGE_SIZE;
|
||||
iop->iov_addr = vdata;
|
||||
iop->iov_size = chunk;
|
||||
vdata += PAGE_SIZE;
|
||||
|
|
@ -916,7 +955,7 @@ void lmfs_rw_scattered(
|
|||
}
|
||||
for (i = 0; i < nblocks; i++) {
|
||||
bp = bufq[i];
|
||||
if (r < (ssize_t) fs_block_size) {
|
||||
if (r < (ssize_t)bp->lmfs_bytes) {
|
||||
/* Transfer failed. */
|
||||
if (i == 0) {
|
||||
bp->lmfs_dev = NO_DEV; /* Invalidate block */
|
||||
|
|
@ -929,7 +968,7 @@ void lmfs_rw_scattered(
|
|||
} else {
|
||||
MARKCLEAN(bp);
|
||||
}
|
||||
r -= fs_block_size;
|
||||
r -= bp->lmfs_bytes;
|
||||
}
|
||||
|
||||
bufq += i;
|
||||
|
|
@ -1126,13 +1165,3 @@ void lmfs_may_use_vmcache(int ok)
|
|||
{
|
||||
may_use_vmcache = ok;
|
||||
}
|
||||
|
||||
void lmfs_reset_rdwt_err(void)
|
||||
{
|
||||
rdwt_err = OK;
|
||||
}
|
||||
|
||||
int lmfs_rdwt_err(void)
|
||||
{
|
||||
return rdwt_err;
|
||||
}
|
||||
|
|
|
|||
7
minix/lib/libminixfs/inc.h
Normal file
7
minix/lib/libminixfs/inc.h
Normal file
|
|
@ -0,0 +1,7 @@
|
|||
#ifndef _LIBMINIXFS_INC_H
|
||||
#define _LIBMINIXFS_INC_H
|
||||
|
||||
int lmfs_get_partial_block(struct buf **bpp, dev_t dev, block64_t block,
|
||||
int how, size_t block_size);
|
||||
|
||||
#endif /* !_LIBMINIXFS_INC_H */
|
||||
|
|
@ -122,7 +122,8 @@ do_mapcache(message *msg)
|
|||
assert(offset < vr->length);
|
||||
|
||||
if(!(hb = find_cached_page_bydev(dev, dev_off + offset,
|
||||
msg->m_vmmcp.ino, ino_off + offset, 1))) {
|
||||
msg->m_vmmcp.ino, ino_off + offset, 1)) ||
|
||||
(hb->flags & VMSF_ONCE)) {
|
||||
map_unmap_region(caller, vr, 0, bytes);
|
||||
return ENOENT;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -140,8 +140,8 @@ static int mappedfile_pagefault(struct vmproc *vmp, struct vir_region *region,
|
|||
if(!cb) {
|
||||
#if 0
|
||||
printf("VM: mem_file: no callback, returning EFAULT\n");
|
||||
#endif
|
||||
sys_diagctl_stacktrace(vmp->vm_endpoint);
|
||||
#endif
|
||||
return EFAULT;
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -59,7 +59,7 @@ MINIX_TESTS= \
|
|||
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 \
|
||||
41 42 43 44 45 46 48 49 50 52 53 54 55 56 58 59 60 \
|
||||
61 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 \
|
||||
81 82 83 84
|
||||
81 82 83 84 85
|
||||
|
||||
FILES += t84_h_nonexec.sh
|
||||
|
||||
|
|
|
|||
|
|
@ -22,7 +22,7 @@ export USENETWORK # set to "yes" for test48+82 to use the network
|
|||
|
||||
# Programs that require setuid
|
||||
setuids="test11 test33 test43 test44 test46 test56 test60 test61 test65 \
|
||||
test69 test73 test74 test78 test83"
|
||||
test69 test73 test74 test78 test83 test85"
|
||||
# Scripts that require to be run as root
|
||||
rootscripts="testisofs testvnd testrelpol"
|
||||
|
||||
|
|
@ -30,7 +30,7 @@ alltests="1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 \
|
|||
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 \
|
||||
41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 \
|
||||
61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 \
|
||||
81 82 83 84 sh1 sh2 interp mfs isofs vnd"
|
||||
81 82 83 84 85 sh1 sh2 interp mfs isofs vnd"
|
||||
tests_no=`expr 0`
|
||||
|
||||
# If root, make sure the setuid tests have the correct permissions
|
||||
|
|
|
|||
|
|
@ -41,10 +41,11 @@ int
|
|||
dowriteblock(int b, int blocksize, u32_t seed, char *data)
|
||||
{
|
||||
struct buf *bp;
|
||||
int r;
|
||||
|
||||
assert(blocksize == curblocksize);
|
||||
|
||||
if(!(bp = lmfs_get_block(MYDEV, b, NORMAL))) {
|
||||
if ((r = lmfs_get_block(&bp, MYDEV, b, NORMAL)) != 0) {
|
||||
e(30);
|
||||
return 0;
|
||||
}
|
||||
|
|
@ -62,10 +63,11 @@ int
|
|||
readblock(int b, int blocksize, u32_t seed, char *data)
|
||||
{
|
||||
struct buf *bp;
|
||||
int r;
|
||||
|
||||
assert(blocksize == curblocksize);
|
||||
|
||||
if(!(bp = lmfs_get_block(MYDEV, b, NORMAL))) {
|
||||
if ((r = lmfs_get_block(&bp, MYDEV, b, NORMAL)) != 0) {
|
||||
e(30);
|
||||
return 0;
|
||||
}
|
||||
|
|
|
|||
540
minix/tests/test85.c
Normal file
540
minix/tests/test85.c
Normal file
|
|
@ -0,0 +1,540 @@
|
|||
/* Test for end-of-file during block device I/O - by D.C. van Moolenbroek */
|
||||
/* This test needs to be run as root; it sets up and uses a VND instance. */
|
||||
/*
|
||||
* The test should work with all root file system block sizes, but only tests
|
||||
* certain corner cases if the root FS block size is twice the page size.
|
||||
*/
|
||||
#include <stdlib.h>
|
||||
#include <string.h>
|
||||
#include <signal.h>
|
||||
#include <sys/param.h>
|
||||
#include <sys/wait.h>
|
||||
#include <sys/mman.h>
|
||||
#include <sys/ioctl.h>
|
||||
#include <minix/partition.h>
|
||||
#include <fcntl.h>
|
||||
#include <unistd.h>
|
||||
#include <assert.h>
|
||||
|
||||
#define VNCONFIG "/usr/sbin/vnconfig"
|
||||
|
||||
#define SECTOR_SIZE 512 /* this should be the sector size of VND */
|
||||
|
||||
#define ITERATIONS 3
|
||||
|
||||
enum {
|
||||
BEFORE_EOF,
|
||||
UPTO_EOF,
|
||||
ACROSS_EOF,
|
||||
ONEPAST_EOF,
|
||||
FROM_EOF,
|
||||
BEYOND_EOF
|
||||
};
|
||||
|
||||
#include "common.h"
|
||||
|
||||
static int need_cleanup = 0;
|
||||
|
||||
static int dev_fd;
|
||||
static size_t dev_size;
|
||||
static char *dev_buf;
|
||||
static char *dev_ref;
|
||||
|
||||
static size_t block_size;
|
||||
static size_t page_size;
|
||||
static int test_peek;
|
||||
|
||||
static char *mmap_ptr = NULL;
|
||||
static size_t mmap_size;
|
||||
|
||||
static int pipe_fd[2];
|
||||
|
||||
/*
|
||||
* Fill the given buffer with random contents.
|
||||
*/
|
||||
static void
|
||||
fill_buf(char * buf, size_t size)
|
||||
{
|
||||
|
||||
while (size--)
|
||||
*buf++ = lrand48() & 0xff;
|
||||
}
|
||||
|
||||
/*
|
||||
* Place the elements of the source array in the destination array in random
|
||||
* order. There are probably better ways to do this, but it is morning, and I
|
||||
* haven't had coffee yet, so go away.
|
||||
*/
|
||||
static void
|
||||
scramble(int * dst, const int * src, int count)
|
||||
{
|
||||
int i, j, k;
|
||||
|
||||
for (i = 0; i < count; i++)
|
||||
dst[i] = i;
|
||||
|
||||
for (i = count - 1; i >= 0; i--) {
|
||||
j = lrand48() % (i + 1);
|
||||
|
||||
k = dst[j];
|
||||
dst[j] = dst[i];
|
||||
dst[i] = src[k];
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Perform I/O using read(2) and check the returned results against the
|
||||
* expected result and the image reference data.
|
||||
*/
|
||||
static void
|
||||
io_read(size_t pos, size_t len, size_t expected)
|
||||
{
|
||||
ssize_t bytes;
|
||||
|
||||
assert(len > 0 && len <= dev_size);
|
||||
assert(expected <= len);
|
||||
|
||||
if (lseek(dev_fd, (off_t)pos, SEEK_SET) != pos) e(0);
|
||||
|
||||
memset(dev_buf, 0, len);
|
||||
|
||||
if ((bytes = read(dev_fd, dev_buf, len)) < 0) e(0);
|
||||
|
||||
if (bytes != expected) e(0);
|
||||
|
||||
if (memcmp(&dev_ref[pos], dev_buf, bytes)) e(0);
|
||||
}
|
||||
|
||||
/*
|
||||
* Perform I/O using write(2) and check the returned result against the
|
||||
* expected result. Update the image reference data as appropriate.
|
||||
*/
|
||||
static void
|
||||
io_write(size_t pos, size_t len, size_t expected)
|
||||
{
|
||||
ssize_t bytes;
|
||||
|
||||
assert(len > 0 && len <= dev_size);
|
||||
assert(expected <= len);
|
||||
|
||||
if (lseek(dev_fd, (off_t)pos, SEEK_SET) != pos) e(0);
|
||||
|
||||
fill_buf(dev_buf, len);
|
||||
|
||||
if ((bytes = write(dev_fd, dev_buf, len)) < 0) e(0);
|
||||
|
||||
if (bytes != expected) e(0);
|
||||
|
||||
if (bytes > 0) {
|
||||
assert(pos + bytes <= dev_size);
|
||||
|
||||
memcpy(&dev_ref[pos], dev_buf, bytes);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Test if reading from the given pointer succeeds or not, and return the
|
||||
* result.
|
||||
*/
|
||||
static int
|
||||
is_readable(char * ptr)
|
||||
{
|
||||
ssize_t r;
|
||||
char byte;
|
||||
|
||||
/*
|
||||
* If we access the pointer directly, we will get a fatal signal.
|
||||
* Thus, for that to work we would need a child process, making the
|
||||
* whole test slow and noisy. Let a service try the operation instead.
|
||||
*/
|
||||
r = write(pipe_fd[1], ptr, 1);
|
||||
|
||||
if (r == 1) {
|
||||
/* Don't fill up the pipe. */
|
||||
if (read(pipe_fd[0], &byte, 1) != 1) e(0);
|
||||
|
||||
return 1;
|
||||
} else if (r != -1 || errno != EFAULT)
|
||||
e(0);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Perform I/O using mmap(2) and check the returned results against the
|
||||
* expected result and the image reference data. Ensure that bytes beyond the
|
||||
* device end are either zero (on the remainder of the last page) or
|
||||
* inaccessible on pages entirely beyond the device end.
|
||||
*/
|
||||
static void
|
||||
io_peek(size_t pos, size_t len, size_t expected)
|
||||
{
|
||||
size_t n, delta, mapped_size;
|
||||
char *ptr;
|
||||
|
||||
assert(test_peek);
|
||||
|
||||
delta = pos % page_size;
|
||||
|
||||
pos -= delta;
|
||||
len += delta;
|
||||
|
||||
len = roundup(len, page_size);
|
||||
|
||||
/* Don't bother with the given expected value. Recompute it. */
|
||||
if (pos < dev_size)
|
||||
expected = MIN(dev_size - pos, len);
|
||||
else
|
||||
expected = 0;
|
||||
|
||||
mapped_size = roundup(dev_size, page_size);
|
||||
|
||||
assert(!(len % page_size));
|
||||
|
||||
ptr = mmap(NULL, len, PROT_READ, MAP_PRIVATE | MAP_FILE, dev_fd,
|
||||
(off_t)pos);
|
||||
|
||||
/*
|
||||
* As of writing, VM allows memory mapping at any offset and for any
|
||||
* length. At least for block devices, VM should probably be changed
|
||||
* to throw ENXIO for any pages beyond the file end, which in turn
|
||||
* renders all the SIGBUS tests below obsolete.
|
||||
*/
|
||||
if (ptr == MAP_FAILED) {
|
||||
if (pos + len <= mapped_size) e(0);
|
||||
if (errno != ENXIO) e(0);
|
||||
|
||||
return;
|
||||
}
|
||||
|
||||
mmap_ptr = ptr;
|
||||
mmap_size = len;
|
||||
|
||||
/*
|
||||
* Any page that contains any valid part of the mapped device should be
|
||||
* readable and have correct contents for that part. If the last valid
|
||||
* page extends beyond the mapped device, its remainder should be zero.
|
||||
*/
|
||||
if (pos < dev_size) {
|
||||
/* The valid part should have the expected device contents. */
|
||||
if (memcmp(&dev_ref[pos], ptr, expected)) e(0);
|
||||
|
||||
/* The remainder, if any, should be zero. */
|
||||
for (n = expected; n % page_size; n++)
|
||||
if (ptr[n] != 0) e(0);
|
||||
}
|
||||
|
||||
/*
|
||||
* Any page entirely beyond EOF should not be mapped in. In order to
|
||||
* ensure that is_readable() works, also test pages that are mapped in.
|
||||
*/
|
||||
for (n = pos; n < pos + len; n += page_size)
|
||||
if (is_readable(&ptr[n - pos]) != (n < mapped_size)) e(0);
|
||||
|
||||
munmap(ptr, len);
|
||||
|
||||
mmap_ptr = NULL;
|
||||
}
|
||||
|
||||
/*
|
||||
* Perform one of the supported end-of-file access attempts using one I/O
|
||||
* operation.
|
||||
*/
|
||||
static void
|
||||
do_one_io(int where, void (* io_proc)(size_t, size_t, size_t))
|
||||
{
|
||||
size_t start, bytes;
|
||||
|
||||
switch (where) {
|
||||
case BEFORE_EOF:
|
||||
bytes = lrand48() % (dev_size - 1) + 1;
|
||||
|
||||
io_proc(dev_size - bytes - 1, bytes, bytes);
|
||||
|
||||
break;
|
||||
|
||||
case UPTO_EOF:
|
||||
bytes = lrand48() % dev_size + 1;
|
||||
|
||||
io_proc(dev_size - bytes, bytes, bytes);
|
||||
|
||||
break;
|
||||
|
||||
case ACROSS_EOF:
|
||||
start = lrand48() % (dev_size - 1) + 1;
|
||||
bytes = dev_size - start + 1;
|
||||
assert(start < dev_size && start + bytes > dev_size);
|
||||
bytes += lrand48() % (dev_size - bytes + 1);
|
||||
|
||||
io_proc(start, bytes, dev_size - start);
|
||||
|
||||
break;
|
||||
|
||||
case ONEPAST_EOF:
|
||||
bytes = lrand48() % (dev_size - 1) + 1;
|
||||
|
||||
io_proc(dev_size - bytes + 1, bytes, bytes - 1);
|
||||
|
||||
break;
|
||||
|
||||
case FROM_EOF:
|
||||
bytes = lrand48() % dev_size + 1;
|
||||
|
||||
io_proc(dev_size, bytes, 0);
|
||||
|
||||
break;
|
||||
|
||||
case BEYOND_EOF:
|
||||
start = dev_size + lrand48() % dev_size + 1;
|
||||
bytes = lrand48() % dev_size + 1;
|
||||
|
||||
io_proc(start, bytes, 0);
|
||||
|
||||
break;
|
||||
|
||||
default:
|
||||
assert(0);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Perform I/O operations, testing all the supported end-of-file access
|
||||
* attempts in a random order so as to detect possible problems with caching.
|
||||
*/
|
||||
static void
|
||||
do_io(void (* io_proc)(size_t, size_t, size_t))
|
||||
{
|
||||
static const int list[] = { BEFORE_EOF, UPTO_EOF, ACROSS_EOF,
|
||||
ONEPAST_EOF, FROM_EOF, BEYOND_EOF };
|
||||
static const int count = sizeof(list) / sizeof(list[0]);
|
||||
int i, where[count];
|
||||
|
||||
scramble(where, list, count);
|
||||
|
||||
for (i = 0; i < count; i++)
|
||||
do_one_io(where[i], io_proc);
|
||||
}
|
||||
|
||||
/*
|
||||
* Set up an image file of the given size, assign it to a VND, and open the
|
||||
* resulting block device. The size is size_t because we keep a reference copy
|
||||
* of its entire contents in memory.
|
||||
*/
|
||||
static void
|
||||
setup_image(size_t size)
|
||||
{
|
||||
struct part_geom part;
|
||||
size_t off;
|
||||
ssize_t bytes;
|
||||
int fd, status;
|
||||
|
||||
dev_size = size;
|
||||
if ((dev_buf = malloc(dev_size)) == NULL) e(0);
|
||||
if ((dev_ref = malloc(dev_size)) == NULL) e(0);
|
||||
|
||||
if ((fd = open("image", O_CREAT | O_TRUNC | O_RDWR, 0644)) < 0) e(0);
|
||||
|
||||
fill_buf(dev_ref, dev_size);
|
||||
|
||||
for (off = 0; off < dev_size; off += bytes) {
|
||||
bytes = write(fd, &dev_ref[off], dev_size - off);
|
||||
|
||||
if (bytes <= 0) e(0);
|
||||
}
|
||||
|
||||
close(fd);
|
||||
|
||||
status = system(VNCONFIG " vnd0 image 2>/dev/null");
|
||||
if (!WIFEXITED(status)) e(0);
|
||||
if (WEXITSTATUS(status) != 0) {
|
||||
printf("skipped\n"); /* most likely cause: vnd0 is in use */
|
||||
cleanup();
|
||||
exit(0);
|
||||
}
|
||||
|
||||
need_cleanup = 1;
|
||||
|
||||
if ((dev_fd = open("/dev/vnd0", O_RDWR)) < 0) e(0);
|
||||
|
||||
if (ioctl(dev_fd, DIOCGETP, &part) < 0) e(0);
|
||||
|
||||
if (part.size != dev_size) e(0);
|
||||
}
|
||||
|
||||
/*
|
||||
* Clean up the VND we set up previously. This function is also called in case
|
||||
* of an unexpected exit.
|
||||
*/
|
||||
static void
|
||||
cleanup_device(void)
|
||||
{
|
||||
int status;
|
||||
|
||||
if (!need_cleanup)
|
||||
return;
|
||||
|
||||
if (mmap_ptr != NULL) {
|
||||
munmap(mmap_ptr, mmap_size);
|
||||
|
||||
mmap_ptr = NULL;
|
||||
}
|
||||
|
||||
if (dev_fd >= 0)
|
||||
close(dev_fd);
|
||||
|
||||
status = system(VNCONFIG " -u vnd0 2>/dev/null");
|
||||
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) e(0);
|
||||
|
||||
need_cleanup = 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Signal handler for exceptions.
|
||||
*/
|
||||
static void
|
||||
got_signal(int __unused sig)
|
||||
{
|
||||
|
||||
cleanup_device();
|
||||
|
||||
exit(1);
|
||||
}
|
||||
|
||||
/*
|
||||
* Clean up the VND and image file we set up previously.
|
||||
*/
|
||||
static void
|
||||
cleanup_image(void)
|
||||
{
|
||||
size_t off;
|
||||
ssize_t bytes;
|
||||
int fd;
|
||||
|
||||
cleanup_device();
|
||||
|
||||
if ((fd = open("image", O_RDONLY, 0644)) < 0) e(0);
|
||||
|
||||
for (off = 0; off < dev_size; off += bytes) {
|
||||
bytes = read(fd, &dev_buf[off], dev_size - off);
|
||||
|
||||
if (bytes <= 0) e(0);
|
||||
}
|
||||
|
||||
close(fd);
|
||||
|
||||
/* Have all changes written back to the device? */
|
||||
if (memcmp(dev_buf, dev_ref, dev_size)) e(0);
|
||||
|
||||
unlink("image");
|
||||
|
||||
free(dev_buf);
|
||||
free(dev_ref);
|
||||
}
|
||||
|
||||
/*
|
||||
* Run the full test for a block device with the given size.
|
||||
*/
|
||||
static void
|
||||
do_test(size_t size)
|
||||
{
|
||||
int i;
|
||||
|
||||
/*
|
||||
* Using the three I/O primitives (read, write, peek), we run four
|
||||
* sequences, mainly to test the effects of blocks being cached or not.
|
||||
* We set up a new image for each sequence, because -if everything goes
|
||||
* right- closing the device file also clears all cached blocks for it,
|
||||
* in both the root file system's cache and the VM cache. Note that we
|
||||
* currently do not even attempt to push the blocks out of the root FS'
|
||||
* cache in order to test retrieval from the VM cache, since this would
|
||||
* involve doing a LOT of extra I/O.
|
||||
*/
|
||||
for (i = 0; i < 4; i++) {
|
||||
setup_image(size);
|
||||
|
||||
switch (i) {
|
||||
case 0:
|
||||
do_io(io_read);
|
||||
|
||||
/* FALLTHROUGH */
|
||||
case 1:
|
||||
do_io(io_write);
|
||||
|
||||
do_io(io_read);
|
||||
|
||||
break;
|
||||
|
||||
case 2:
|
||||
do_io(io_peek);
|
||||
|
||||
/* FALLTHROUGH */
|
||||
|
||||
case 3:
|
||||
do_io(io_write);
|
||||
|
||||
do_io(io_peek);
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
cleanup_image();
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Test program for end-of-file conditions during block device I/O.
|
||||
*/
|
||||
int
|
||||
main(void)
|
||||
{
|
||||
static const unsigned int blocks[] = { 1, 4, 3, 5, 2 };
|
||||
struct statvfs buf;
|
||||
int i, j;
|
||||
|
||||
start(85);
|
||||
|
||||
signal(SIGINT, got_signal);
|
||||
signal(SIGABRT, got_signal);
|
||||
signal(SIGSEGV, got_signal);
|
||||
signal(SIGBUS, got_signal);
|
||||
atexit(cleanup_device);
|
||||
|
||||
srand48(time(NULL));
|
||||
|
||||
if (pipe(pipe_fd) != 0) e(0);
|
||||
|
||||
/*
|
||||
* Get the system page size, and align all memory mapping offsets and
|
||||
* sizes accordingly.
|
||||
*/
|
||||
page_size = sysconf(_SC_PAGESIZE);
|
||||
|
||||
/*
|
||||
* Get the root file system block size. In the current MINIX3 system
|
||||
* architecture, the root file system's block size determines the
|
||||
* transfer granularity for I/O on unmounted block devices. If this
|
||||
* block size is not a multiple of the page size, we are (currently!)
|
||||
* not expecting memory-mapped block devices to work.
|
||||
*/
|
||||
if (statvfs("/", &buf) < 0) e(0);
|
||||
|
||||
block_size = buf.f_bsize;
|
||||
|
||||
test_peek = !(block_size % page_size);
|
||||
|
||||
for (i = 0; i < ITERATIONS; i++) {
|
||||
/*
|
||||
* The 'blocks' array is scrambled so as to detect any blocks
|
||||
* left in the VM cache (or not) across runs, just in case.
|
||||
*/
|
||||
for (j = 0; j < sizeof(blocks) / sizeof(blocks[0]); j++) {
|
||||
do_test(blocks[j] * block_size + SECTOR_SIZE);
|
||||
|
||||
do_test(blocks[j] * block_size);
|
||||
|
||||
do_test(blocks[j] * block_size - SECTOR_SIZE);
|
||||
}
|
||||
}
|
||||
|
||||
quit();
|
||||
}
|
||||
Loading…
Reference in a new issue