Add inode operations.
Signed-off-by: Marco Stornelli <marco.stornelli@xxxxxxxxx>
---
fs/pramfs/inode.c | 907 +++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 907 insertions(+), 0 deletions(-)
create mode 100644 fs/pramfs/inode.c
diff --git a/fs/pramfs/inode.c b/fs/pramfs/inode.c
new file mode 100644
index 0000000..d0f03b1
--- /dev/null
+++ b/fs/pramfs/inode.c
@@ -0,0 +1,907 @@
+/*
+ * BRIEF DESCRIPTION
+ *
+ * Inode methods (allocate/free/read/write).
+ *
+ * Copyright 2009-2011 Marco Stornelli <marco.stornelli@xxxxxxxxx>
+ * Copyright 2003 Sony Corporation
+ * Copyright 2003 Matsushita Electric Industrial Co., Ltd.
+ * 2003-2004 (c) MontaVista Software, Inc. , Steve Longerbeam
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/highuid.h>
+#include <linux/module.h>
+#include <linux/mpage.h>
+#include <linux/backing-dev.h>
+#include "pram.h"
+#include "xattr.h"
+#include "xip.h"
+#include "acl.h"
+
+struct backing_dev_info pram_backing_dev_info __read_mostly = {
+ .ra_pages = 0, /* No readahead */
+ .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK,
+};
+
+/*
+ * allocate a data block for inode and return it's absolute blocknr.
+ * Zeroes out the block if zero set. Increments inode->i_blocks.
+ */
+static int pram_new_data_block(struct inode *inode, unsigned long *blocknr,
+ int zero)
+{
+ int errval = pram_new_block(inode->i_sb, blocknr, zero);
+
+ if (!errval) {
+ struct pram_inode *pi = pram_get_inode(inode->i_sb,
+ inode->i_ino);
+ inode->i_blocks++;
+ pram_memunlock_inode(inode->i_sb, pi);
+ pi->i_blocks = cpu_to_be32(inode->i_blocks);
+ pram_memlock_inode(inode->i_sb, pi);
+ }
+
+ return errval;
+}
+
+/*
+ * find the offset to the block represented by the given inode's file
+ * relative block number.
+ */
+u64 pram_find_data_block(struct inode *inode, unsigned long file_blocknr)
+{
+ struct super_block *sb = inode->i_sb;
+ struct pram_inode *pi;
+ u64 *row; /* ptr to row block */
+ u64 *col; /* ptr to column blocks */
+ u64 bp = 0;
+ unsigned int i_row, i_col;
+ unsigned int N = sb->s_blocksize >> 3; /* num block ptrs per block */
+ unsigned int Nbits = sb->s_blocksize_bits - 3;
+
+ pi = pram_get_inode(sb, inode->i_ino);
+
+ i_row = file_blocknr >> Nbits;
+ i_col = file_blocknr & (N-1);
+
+ row = pram_get_block(sb, be64_to_cpu(pi->i_type.reg.row_block));
+ if (row) {
+ col = pram_get_block(sb, be64_to_cpu(row[i_row]));
+ if (col)
+ bp = be64_to_cpu(col[i_col]);
+ }
+
+ return bp;
+}
+
+/*
+ * find the file offset for SEEK_DATA/SEEK_HOLE
+ */
+int pram_find_region(struct inode *inode, loff_t *offset, int hole)
+{
+ struct super_block *sb = inode->i_sb;
+ struct pram_inode *pi = pram_get_inode(sb, inode->i_ino);
+ int N = sb->s_blocksize >> 3; /* num block ptrs per block */
+ int first_row_index, last_row_index, i, j;
+ unsigned long first_blocknr, last_blocknr, blocks = 0, offset_in_block;
+ u64 *row; /* ptr to row block */
+ u64 *col; /* ptr to column blocks */
+ int data_found = 0, hole_found = 0;
+
+ if (*offset >= inode->i_size)
+ return -ENXIO;
+
+ if (!inode->i_blocks || !pi->i_type.reg.row_block) {
+ if (hole)
+ return inode->i_size;
+ else
+ return -ENXIO;
+ }
+
+ offset_in_block = *offset & (sb->s_blocksize - 1);
+
+ first_blocknr = *offset >> sb->s_blocksize_bits;
+ last_blocknr = inode->i_size >> sb->s_blocksize_bits;
+
+ first_row_index = first_blocknr >> (sb->s_blocksize_bits - 3);
+ last_row_index = last_blocknr >> (sb->s_blocksize_bits - 3);
+
+ row = pram_get_block(sb, be64_to_cpu(pi->i_type.reg.row_block));
+
+ for (i = first_row_index; i <= last_row_index; i++) {
+ int first_col_index = (i == first_row_index) ?
+ first_blocknr & (N-1) : 0;
+ int last_col_index = (i == last_row_index) ?
+ last_blocknr & (N-1) : N-1;
+
+ if (!row[i]) {
+ hole_found = 1;
+ if (!hole)
+ blocks += sb->s_blocksize >> 3;
+ continue;
+ }
+
+ col = pram_get_block(sb, be64_to_cpu(row[i]));
+
+ for (j = first_col_index; j <= last_col_index; j++) {
+
+ if (col[j]) {
+ data_found = 1;
+ if (!hole)
+ goto out;
+ } else
+ hole_found = 1;
+
+ if (!hole_found || !hole)
+ blocks++;
+ }
+ cond_resched();
+ }
+ out:
+ /* Searching data but only hole found till the end */
+ if (!hole && !data_found && hole_found)
+ return -ENXIO;
+
+ if (data_found && !hole_found) {
+ /* Searching data but we are alredy into them */
+ if (!hole)
+ return 0;
+ /* Searching hole but only data found, go to the end */
+ else {
+ *offset = inode->i_size;
+ return 0;
+ }
+ }
+
+ /* Searching for hole, hole found and starting inside an hole */
+ if (hole && hole_found && !blocks) {
+ /* we found data after it */
+ if (data_found)
+ return 0;
+ else {
+ /* last hole */
+ *offset = inode->i_size;
+ return 0;
+ }
+ }
+
+ if (offset_in_block) {
+ blocks--;
+ *offset += (blocks << sb->s_blocksize_bits) +
+ (sb->s_blocksize - offset_in_block);
+ } else
+ *offset += blocks << sb->s_blocksize_bits;
+
+ return 0;
+}
+
+/*
+ * Free data blocks from inode in the range start <=> end
+ */
+static void __pram_truncate_blocks(struct inode *inode, loff_t start,
+ loff_t end)
+{
+ struct super_block *sb = inode->i_sb;
+ struct pram_inode *pi = pram_get_inode(sb, inode->i_ino);
+ int N = sb->s_blocksize >> 3; /* num block ptrs per block */
+ int Nbits = sb->s_blocksize_bits - 3;
+ int first_row_index, last_row_index, i, j;
+ unsigned long blocknr, first_blocknr, last_blocknr;
+ unsigned int freed = 0;
+ u64 *row; /* ptr to row block */
+ u64 *col; /* ptr to column blocks */
+
+ if (!pi->i_type.reg.row_block)
+ return;
+
+ first_blocknr = (start + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
+
+ if (pi->i_flags & cpu_to_be32(PRAM_EOFBLOCKS_FL))
+ last_blocknr = (1UL << (2*sb->s_blocksize_bits - 6)) - 1;
+ else
+ last_blocknr = end >> sb->s_blocksize_bits;
+
+ if (first_blocknr > last_blocknr)
+ return;
+
+ first_row_index = first_blocknr >> Nbits;
+ last_row_index = last_blocknr >> Nbits;
+
+ row = pram_get_block(sb, be64_to_cpu(pi->i_type.reg.row_block));
+
+ for (i = first_row_index; i <= last_row_index; i++) {
+ int first_col_index = (i == first_row_index) ?
+ first_blocknr & (N-1) : 0;
+ int last_col_index = (i == last_row_index) ?
+ last_blocknr & (N-1) : N-1;
+
+ if (unlikely(!row[i]))
+ continue;
+
+ col = pram_get_block(sb, be64_to_cpu(row[i]));
+
+ for (j = first_col_index; j <= last_col_index; j++) {
+
+ if (unlikely(!col[j]))
+ continue;
+
+ blocknr = pram_get_blocknr(sb, be64_to_cpu(col[j]));
+ pram_free_block(sb, blocknr);
+ freed++;
+ pram_memunlock_block(sb, col);
+ col[j] = 0;
+ pram_memlock_block(sb, col);
+ }
+
+ cond_resched();
+
+ if (first_col_index == 0) {
+ blocknr = pram_get_blocknr(sb, be64_to_cpu(row[i]));
+ pram_free_block(sb, blocknr);
+ pram_memunlock_block(sb, row);
+ row[i] = 0;
+ pram_memlock_block(sb, row);
+ }
+ }
+
+ inode->i_blocks -= freed;
+
+ if (start == 0) {
+ blocknr = pram_get_blocknr(sb,
+ be64_to_cpu(pi->i_type.reg.row_block));
+ pram_free_block(sb, blocknr);
+ pram_memunlock_inode(sb, pi);
+ pi->i_type.reg.row_block = 0;
+ goto update_blocks;
+ }
+ pram_memunlock_inode(sb, pi);
+
+ update_blocks:
+ pi->i_blocks = cpu_to_be32(inode->i_blocks);
+ pram_memlock_inode(sb, pi);
+}
+
+static void pram_truncate_blocks(struct inode *inode, loff_t start, loff_t end)
+{
+ if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+ S_ISLNK(inode->i_mode)))
+ return;
+
+ __pram_truncate_blocks(inode, start, end);
+ inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
+ pram_update_inode(inode);
+}
+
+/*
+ * Allocate num data blocks for inode, starting at given file-relative
+ * block number.
+ */
+int pram_alloc_blocks(struct inode *inode, int file_blocknr, unsigned int num)
+{
+ struct super_block *sb = inode->i_sb;
+ struct pram_inode *pi = pram_get_inode(sb, inode->i_ino);
+ int N = sb->s_blocksize >> 3; /* num block ptrs per block */
+ int Nbits = sb->s_blocksize_bits - 3;
+ int first_file_blocknr;
+ int last_file_blocknr;
+ int first_row_index, last_row_index;
+ int i, j, errval;
+ unsigned long blocknr;
+ u64 *row;
+ u64 *col;
+
+ if (!pi->i_type.reg.row_block) {
+ /* alloc the 2nd order array block */
+ errval = pram_new_block(sb, &blocknr, 1);
+ if (errval) {
+ pram_dbg("failed to alloc 2nd order array block\n");
+ goto fail;
+ }
+ pram_memunlock_inode(sb, pi);
+ pi->i_type.reg.row_block = cpu_to_be64(pram_get_block_off(sb,
+ blocknr));
+ pram_memlock_inode(sb, pi);
+ }
+
+ row = pram_get_block(sb, be64_to_cpu(pi->i_type.reg.row_block));
+
+ first_file_blocknr = file_blocknr;
+ last_file_blocknr = file_blocknr + num - 1;
+
+ first_row_index = first_file_blocknr >> Nbits;
+ last_row_index = last_file_blocknr >> Nbits;
+
+ for (i = first_row_index; i <= last_row_index; i++) {
+ int first_col_index, last_col_index;
+
+ /*
+ * we are starting a new row, so make sure
+ * there is a block allocated for the row.
+ */
+ if (!row[i]) {
+ /* allocate the row block */
+ errval = pram_new_block(sb, &blocknr, 1);
+ if (errval) {
+ pram_dbg("failed to alloc row block\n");
+ goto fail;
+ }
+ pram_memunlock_block(sb, row);
+ row[i] = cpu_to_be64(pram_get_block_off(sb, blocknr));
+ pram_memlock_block(sb, row);
+ }
+ col = pram_get_block(sb, be64_to_cpu(row[i]));
+
+ first_col_index = (i == first_row_index) ?
+ first_file_blocknr & (N-1) : 0;
+
+ last_col_index = (i == last_row_index) ?
+ last_file_blocknr & (N-1) : N-1;
+
+ for (j = first_col_index; j <= last_col_index; j++) {
+ if (!col[j]) {
+ errval = pram_new_data_block(inode, &blocknr,
+ 1);
+ if (errval) {
+ pram_dbg("fail to alloc data block\n");
+ if (j != first_col_index) {
+ __pram_truncate_blocks(inode,
+ inode->i_size,
+ inode->i_size + ((j - first_col_index)
+ << inode->i_sb->s_blocksize_bits));
+ }
+ goto fail;
+ }
+ pram_memunlock_block(sb, col);
+ col[j] = cpu_to_be64(pram_get_block_off(sb,
+ blocknr));
+ pram_memlock_block(sb, col);
+ }
+ }
+ }
+
+ errval = 0;
+ fail:
+ return errval;
+}
+
+static int pram_read_inode(struct inode *inode, struct pram_inode *pi)
+{
+ int ret = -EIO;
+
+ mutex_lock(&PRAM_I(inode)->i_meta_mutex);
+
+ if (pram_calc_checksum((u8 *)pi, PRAM_INODE_SIZE)) {
+ pram_err(inode->i_sb, "checksum error in inode %08x\n",
+ (u32)inode->i_ino);
+ goto bad_inode;
+ }
+
+ inode->i_mode = be16_to_cpu(pi->i_mode);
+ i_uid_write(inode, be32_to_cpu(pi->i_uid));
+ i_gid_write(inode, be32_to_cpu(pi->i_gid));
+ set_nlink(inode, be16_to_cpu(pi->i_links_count));
+ inode->i_size = be32_to_cpu(pi->i_size);
+ inode->i_atime.tv_sec = be32_to_cpu(pi->i_atime);
+ inode->i_ctime.tv_sec = be32_to_cpu(pi->i_ctime);
+ inode->i_mtime.tv_sec = be32_to_cpu(pi->i_mtime);
+ inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec =
+ inode->i_ctime.tv_nsec = 0;
+ inode->i_generation = be32_to_cpu(pi->i_generation);
+ pram_set_inode_flags(inode, pi);
+
+ /* check if the inode is active. */
+ if (inode->i_nlink == 0 && (inode->i_mode == 0 ||
+ be32_to_cpu(pi->i_dtime))) {
+ /* this inode is deleted */
+ pram_dbg("read inode: inode %lu not active", inode->i_ino);
+ ret = -ESTALE;
+ goto bad_inode;
+ }
+
+ inode->i_blocks = be32_to_cpu(pi->i_blocks);
+ inode->i_ino = pram_get_inodenr(inode->i_sb, pi);
+ inode->i_mapping->a_ops = &pram_aops;
+ inode->i_mapping->backing_dev_info = &pram_backing_dev_info;
+
+ switch (inode->i_mode & S_IFMT) {
+ case S_IFREG:
+ if (pram_use_xip(inode->i_sb)) {
+ inode->i_mapping->a_ops = &pram_aops_xip;
+ inode->i_fop = &pram_xip_file_operations;
+ } else {
+ inode->i_op = &pram_file_inode_operations;
+ inode->i_fop = &pram_file_operations;
+ }
+ break;
+ case S_IFDIR:
+ inode->i_op = &pram_dir_inode_operations;
+ inode->i_fop = &pram_dir_operations;
+ break;
+ case S_IFLNK:
+ inode->i_op = &pram_symlink_inode_operations;
+ break;
+ default:
+ inode->i_size = 0;
+ inode->i_op = &pram_special_inode_operations;
+ init_special_inode(inode, inode->i_mode,
+ be32_to_cpu(pi->i_type.dev.rdev));
+ break;
+ }
+
+ mutex_unlock(&PRAM_I(inode)->i_meta_mutex);
+ return 0;
+
+ bad_inode:
+ mutex_unlock(&PRAM_I(inode)->i_meta_mutex);
+ return ret;
+}
+
+int pram_update_inode(struct inode *inode)
+{
+ struct pram_inode *pi;
+ int retval = 0;
+
+ pi = pram_get_inode(inode->i_sb, inode->i_ino);
+ if (!pi)
+ return -EACCES;
+
+ mutex_lock(&PRAM_I(inode)->i_meta_mutex);
+
+ pram_memunlock_inode(inode->i_sb, pi);
+ pi->i_mode = cpu_to_be16(inode->i_mode);
+ pi->i_uid = cpu_to_be32(i_uid_read(inode));
+ pi->i_gid = cpu_to_be32(i_gid_read(inode));
+ pi->i_links_count = cpu_to_be16(inode->i_nlink);
+ pi->i_size = cpu_to_be32(inode->i_size);
+ pi->i_blocks = cpu_to_be32(inode->i_blocks);
+ pi->i_atime = cpu_to_be32(inode->i_atime.tv_sec);
+ pi->i_ctime = cpu_to_be32(inode->i_ctime.tv_sec);
+ pi->i_mtime = cpu_to_be32(inode->i_mtime.tv_sec);
+ pi->i_generation = cpu_to_be32(inode->i_generation);
+ pram_get_inode_flags(inode, pi);
+
+ if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
+ pi->i_type.dev.rdev = cpu_to_be32(inode->i_rdev);
+
+ pram_memlock_inode(inode->i_sb, pi);
+
+ mutex_unlock(&PRAM_I(inode)->i_meta_mutex);
+ return retval;
+}
+
+/*
+ * NOTE! When we get the inode, we're the only people
+ * that have access to it, and as such there are no
+ * race conditions we have to worry about. The inode
+ * is not on the hash-lists, and it cannot be reached
+ * through the filesystem because the directory entry
+ * has been deleted earlier.
+ */
+static void pram_free_inode(struct inode *inode)
+{
+ struct super_block *sb = inode->i_sb;
+ struct pram_super_block *ps;
+ struct pram_inode *pi;
+ unsigned long inode_nr;
+
+ pram_xattr_delete_inode(inode);
+
+ mutex_lock(&PRAM_SB(sb)->s_lock);
+
+ inode_nr = (inode->i_ino - PRAM_ROOT_INO) >> PRAM_INODE_BITS;
+
+ pi = pram_get_inode(sb, inode->i_ino);
+ pram_memunlock_inode(sb, pi);
+ pi->i_dtime = cpu_to_be32(get_seconds());
+ pi->i_type.reg.row_block = 0;
+ pi->i_xattr = 0;
+ pram_memlock_inode(sb, pi);
+
+ /* increment s_free_inodes_count */
+ ps = pram_get_super(sb);
+ pram_memunlock_super(sb, ps);
+ if (inode_nr < be32_to_cpu(ps->s_free_inode_hint))
+ ps->s_free_inode_hint = cpu_to_be32(inode_nr);
+ be32_add_cpu(&ps->s_free_inodes_count, 1);
+ if (be32_to_cpu(ps->s_free_inodes_count) ==
+ be32_to_cpu(ps->s_inodes_count) - 1) {
+ /* filesystem is empty */
+ pram_dbg("fs is empty!\n");
+ ps->s_free_inode_hint = cpu_to_be32(1);
+ }
+ pram_memlock_super(sb, ps);
+
+ mutex_unlock(&PRAM_SB(sb)->s_lock);
+}
+
+struct inode *pram_iget(struct super_block *sb, unsigned long ino)
+{
+ struct inode *inode;
+ struct pram_inode *pi;
+ int err;
+
+ inode = iget_locked(sb, ino);
+ if (unlikely(!inode))
+ return ERR_PTR(-ENOMEM);
+ if (!(inode->i_state & I_NEW))
+ return inode;
+
+ pi = pram_get_inode(sb, ino);
+ if (!pi) {
+ err = -EACCES;
+ goto fail;
+ }
+ err = pram_read_inode(inode, pi);
+ if (unlikely(err))
+ goto fail;
+
+ unlock_new_inode(inode);
+ return inode;
+fail:
+ iget_failed(inode);
+ return ERR_PTR(err);
+}
+
+void pram_evict_inode(struct inode *inode)
+{
+ int want_delete = 0;
+
+ if (!inode->i_nlink && !is_bad_inode(inode))
+ want_delete = 1;
+
+ truncate_inode_pages(&inode->i_data, 0);
+
+ if (want_delete) {
+ sb_start_intwrite(inode->i_sb);
+ /* unlink from chain in the inode's directory */
+ pram_remove_link(inode);
+ pram_truncate_blocks(inode, 0, inode->i_size);
+ inode->i_size = 0;
+ }
+
+ clear_inode(inode);
+
+ if (want_delete) {
+ pram_free_inode(inode);
+ sb_end_intwrite(inode->i_sb);
+ }
+}
+
+
+struct inode *pram_new_inode(struct inode *dir, umode_t mode,
+ const struct qstr *qstr)
+{
+ struct super_block *sb;
+ struct pram_sb_info *sbi;
+ struct pram_super_block *ps;
+ struct inode *inode;
+ struct pram_inode *pi = NULL;
+ struct pram_inode *diri = NULL;
+ int i, errval;
+ ino_t ino = 0;
+
+ sb = dir->i_sb;
+ sbi = (struct pram_sb_info *)sb->s_fs_info;
+ inode = new_inode(sb);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_lock(&PRAM_SB(sb)->s_lock);
+ ps = pram_get_super(sb);
+
+ if (ps->s_free_inodes_count) {
+ /* find the oldest unused pram inode */
+ for (i = be32_to_cpu(ps->s_free_inode_hint);
+ i < be32_to_cpu(ps->s_inodes_count); i++) {
+ ino = PRAM_ROOT_INO + (i << PRAM_INODE_BITS);
+ pi = pram_get_inode(sb, ino);
+ /* check if the inode is active. */
+ if (be16_to_cpu(pi->i_links_count) == 0 &&
+ (be16_to_cpu(pi->i_mode) == 0 ||
+ be32_to_cpu(pi->i_dtime))) {
+ /* this inode is deleted */
+ break;
+ }
+ }
+
+ if (unlikely(i >= be32_to_cpu(ps->s_inodes_count))) {
+ pram_err(sb, "free inodes count!=0 but none free!?\n");
+ errval = -ENOSPC;
+ goto fail1;
+ }
+
+ pram_dbg("allocating inode %lu\n", ino);
+ } else {
+ pram_dbg("no space left to create new inode!\n");
+ errval = -ENOSPC;
+ goto fail1;
+ }
+
+ diri = pram_get_inode(sb, dir->i_ino);
+ if (!diri) {
+ errval = -EACCES;
+ goto fail1;
+ }
+
+ /* chosen inode is in ino */
+ inode->i_ino = ino;
+ inode_init_owner(inode, dir, mode);
+ inode->i_blocks = inode->i_size = 0;
+ inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+
+ inode->i_generation = atomic_add_return(1, &sbi->next_generation);
+
+ pram_memunlock_inode(sb, pi);
+ pi->i_d.d_next = 0;
+ pi->i_d.d_prev = 0;
+ pi->i_dtime = 0;
+ pi->i_flags = pram_mask_flags(mode, diri->i_flags);
+ pram_memlock_inode(sb, pi);
+
+ pram_set_inode_flags(inode, pi);
+
+ if (insert_inode_locked(inode) < 0) {
+ errval = -EINVAL;
+ goto fail1;
+ }
+ errval = pram_write_inode(inode, NULL);
+ if (errval)
+ goto fail2;
+
+ errval = pram_init_acl(inode, dir);
+ if (errval)
+ goto fail2;
+
+ errval = pram_init_security(inode, dir, qstr);
+ if (errval)
+ goto fail2;
+
+ pram_memunlock_super(sb, ps);
+ be32_add_cpu(&ps->s_free_inodes_count, -1);
+ if (i < be32_to_cpu(ps->s_inodes_count)-1)
+ ps->s_free_inode_hint = cpu_to_be32(i+1);
+ else
+ ps->s_free_inode_hint = 0;
+ pram_memlock_super(sb, ps);
+
+ mutex_unlock(&PRAM_SB(sb)->s_lock);
+
+ return inode;
+fail2:
+ mutex_unlock(&PRAM_SB(sb)->s_lock);
+ clear_nlink(inode);
+ unlock_new_inode(inode);
+ iput(inode);
+ return ERR_PTR(errval);
+fail1:
+ mutex_unlock(&PRAM_SB(sb)->s_lock);
+ make_bad_inode(inode);
+ iput(inode);
+ return ERR_PTR(errval);
+}
+
+int pram_write_inode(struct inode *inode, struct writeback_control *wbc)
+{
+ return pram_update_inode(inode);
+}
+
+/*
+ * dirty_inode() is called from __mark_inode_dirty()
+ */
+void pram_dirty_inode(struct inode *inode, int flags)
+{
+ pram_update_inode(inode);
+}
+
+static int pram_readpage(struct file *file, struct page *page)
+{
+ struct inode *inode = page->mapping->host;
+ struct super_block *sb = inode->i_sb;
+ loff_t offset, size;
+ unsigned long fillsize, blocknr, bytes_filled;
+ u64 block;
+ void *buf, *bp;
+ int ret;
+
+ buf = kmap(page);
+ if (!buf)
+ return -ENOMEM;
+
+ offset = page_offset(page);
+ size = i_size_read(inode);
+ blocknr = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ fillsize = 0;
+ bytes_filled = 0;
+ ret = 0;
+ if (offset < size) {
+ size -= offset;
+ fillsize = size > PAGE_SIZE ? PAGE_SIZE : size;
+ while (fillsize) {
+ int count = fillsize > sb->s_blocksize ?
+ sb->s_blocksize : fillsize;
+ block = pram_find_data_block(inode, blocknr);
+ if (likely(block)) {
+ bp = pram_get_block(sb, block);
+ if (!bp) {
+ SetPageError(page);
+ bytes_filled = 0;
+ ret = -EIO;
+ goto out;
+ }
+ memcpy(buf + bytes_filled, bp, count);
+ } else {
+ memset(buf + bytes_filled, 0, count);
+ }
+ bytes_filled += count;
+ fillsize -= count;
+ blocknr++;
+ }
+ }
+ out:
+ if (bytes_filled < PAGE_SIZE)
+ memset(buf + bytes_filled, 0, PAGE_SIZE - bytes_filled);
+ if (ret == 0)
+ SetPageUptodate(page);
+
+ flush_dcache_page(page);
+ kunmap(page);
+ unlock_page(page);
+ return ret;
+}
+
+/*
+ * Called to zeros out a single block. It's used in the "resize"
+ * to avoid to keep data in case the file grow up again.
+ */
+static int pram_block_truncate_page(struct inode *inode, loff_t newsize)
+{
+ struct super_block *sb = inode->i_sb;
+ unsigned long offset = newsize & (sb->s_blocksize - 1);
+ unsigned long blocknr, length;
+ u64 blockoff;
+ char *bp;
+ int ret = 0;
+
+ /* Block boundary or extending ? */
+ if (!offset || newsize > inode->i_size)
+ goto out;
+
+ length = sb->s_blocksize - offset;
+ blocknr = newsize >> sb->s_blocksize_bits;
+
+ blockoff = pram_find_data_block(inode, blocknr);
+
+ /* Hole ? */
+ if (!blockoff)
+ goto out;
+
+ bp = pram_get_block(inode->i_sb, blockoff);
+ if (!bp) {
+ ret = -EACCES;
+ goto out;
+ }
+ pram_memunlock_block(sb, bp);
+ memset(bp + offset, 0, length);
+ pram_memlock_block(sb, bp);
+out:
+ return ret;
+}
+
+static int pram_setsize(struct inode *inode, loff_t newsize)
+{
+ int ret = 0;
+ loff_t oldsize = inode->i_size;
+
+ if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+ S_ISLNK(inode->i_mode)))
+ return -EINVAL;
+ if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+ return -EPERM;
+
+ if (newsize != oldsize) {
+ if (mapping_is_xip(inode->i_mapping))
+ ret = xip_truncate_page(inode->i_mapping, newsize);
+ else
+ ret = pram_block_truncate_page(inode, newsize);
+
+ if (ret)
+ return ret;
+ i_size_write(inode, newsize);
+ }
+ /*
+ * Wait for any concurrent readers to finish before to truncate the
+ * blocks. Any new reader will see the new i_size so no problem.
+ * In addition we have to wait, in xip case, the call of xip_file_fault.
+ */
+ synchronize_rcu();
+ truncate_pagecache(inode, oldsize, newsize);
+ __pram_truncate_blocks(inode, newsize, oldsize);
+ /* Check for the flag EOFBLOCKS is still valid after the set size */
+ check_eof_blocks(inode, newsize);
+ inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
+ pram_update_inode(inode);
+
+ return ret;
+}
+
+int pram_notify_change(struct dentry *dentry, struct iattr *attr)
+{
+ struct inode *inode = dentry->d_inode;
+ struct pram_inode *pi = pram_get_inode(inode->i_sb, inode->i_ino);
+ int error;
+
+ if (!pi)
+ return -EACCES;
+
+ error = inode_change_ok(inode, attr);
+ if (error)
+ return error;
+
+ if (attr->ia_valid & ATTR_SIZE &&
+ (attr->ia_size != inode->i_size ||
+ pi->i_flags & cpu_to_be32(PRAM_EOFBLOCKS_FL))) {
+ error = pram_setsize(inode, attr->ia_size);
+ if (error)
+ return error;
+ }
+ setattr_copy(inode, attr);
+ if (attr->ia_valid & ATTR_MODE)
+ error = pram_acl_chmod(inode);
+ error = pram_update_inode(inode);
+
+ return error;
+}
+
+void pram_set_inode_flags(struct inode *inode, struct pram_inode *pi)
+{
+ unsigned int flags = be32_to_cpu(pi->i_flags);
+
+ inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
+ if (flags & FS_SYNC_FL)
+ inode->i_flags |= S_SYNC;
+ if (flags & FS_APPEND_FL)
+ inode->i_flags |= S_APPEND;
+ if (flags & FS_IMMUTABLE_FL)
+ inode->i_flags |= S_IMMUTABLE;
+ if (flags & FS_NOATIME_FL)
+ inode->i_flags |= S_NOATIME;
+ if (flags & FS_DIRSYNC_FL)
+ inode->i_flags |= S_DIRSYNC;
+ if (!pi->i_xattr)
+ inode_has_no_xattr(inode);
+}
+
+void pram_get_inode_flags(struct inode *inode, struct pram_inode *pi)
+{
+ unsigned int flags = inode->i_flags;
+ unsigned int pram_flags = be32_to_cpu(pi->i_flags);
+
+ pram_flags &= ~(FS_SYNC_FL|FS_APPEND_FL|FS_IMMUTABLE_FL|
+ FS_NOATIME_FL|FS_DIRSYNC_FL);
+ if (flags & S_SYNC)
+ pram_flags |= FS_SYNC_FL;
+ if (flags & S_APPEND)
+ pram_flags |= FS_APPEND_FL;
+ if (flags & S_IMMUTABLE)
+ pram_flags |= FS_IMMUTABLE_FL;
+ if (flags & S_NOATIME)
+ pram_flags |= FS_NOATIME_FL;
+ if (flags & S_DIRSYNC)
+ pram_flags |= FS_DIRSYNC_FL;
+
+ pi->i_flags = cpu_to_be32(pram_flags);
+}
+
+const struct address_space_operations pram_aops = {
+ .readpage = pram_readpage,
+ .direct_IO = pram_direct_IO,
+};
+
+const struct address_space_operations pram_aops_xip = {
+ .get_xip_mem = pram_get_xip_mem,
+};
--
1.7.3.4
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