X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Fread_write.c;h=969a6d9c020ba01644578b04c86043b15e98b53a;hb=14800984706bf6936bbec5187f736e928be5c218;hp=ea1f94cc722e0c942111b9849cedf8b1aef1d86a;hpb=d89a9bda14204547f966ed1510a269a44c0b7f5d;p=linux-2.6-omap-h63xx.git diff --git a/fs/read_write.c b/fs/read_write.c index ea1f94cc722..969a6d9c020 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -31,57 +31,63 @@ const struct file_operations generic_ro_fops = { EXPORT_SYMBOL(generic_ro_fops); -loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) +/** + * generic_file_llseek_unlocked - lockless generic llseek implementation + * @file: file structure to seek on + * @offset: file offset to seek to + * @origin: type of seek + * + * Updates the file offset to the value specified by @offset and @origin. + * Locking must be provided by the caller. + */ +loff_t +generic_file_llseek_unlocked(struct file *file, loff_t offset, int origin) { - long long retval; struct inode *inode = file->f_mapping->host; - mutex_lock(&inode->i_mutex); switch (origin) { - case SEEK_END: - offset += inode->i_size; - break; - case SEEK_CUR: - offset += file->f_pos; + case SEEK_END: + offset += inode->i_size; + break; + case SEEK_CUR: + offset += file->f_pos; + break; } - retval = -EINVAL; - if (offset>=0 && offset<=inode->i_sb->s_maxbytes) { - if (offset != file->f_pos) { - file->f_pos = offset; - file->f_version = 0; - } - retval = offset; + + if (offset < 0 || offset > inode->i_sb->s_maxbytes) + return -EINVAL; + + /* Special lock needed here? */ + if (offset != file->f_pos) { + file->f_pos = offset; + file->f_version = 0; } - mutex_unlock(&inode->i_mutex); - return retval; -} -EXPORT_SYMBOL(generic_file_llseek); + return offset; +} +EXPORT_SYMBOL(generic_file_llseek_unlocked); -loff_t remote_llseek(struct file *file, loff_t offset, int origin) +/** + * generic_file_llseek - generic llseek implementation for regular files + * @file: file structure to seek on + * @offset: file offset to seek to + * @origin: type of seek + * + * This is a generic implemenation of ->llseek useable for all normal local + * filesystems. It just updates the file offset to the value specified by + * @offset and @origin under i_mutex. + */ +loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) { - long long retval; + loff_t rval; - lock_kernel(); - switch (origin) { - case SEEK_END: - offset += i_size_read(file->f_path.dentry->d_inode); - break; - case SEEK_CUR: - offset += file->f_pos; - } - retval = -EINVAL; - if (offset>=0 && offset<=file->f_path.dentry->d_inode->i_sb->s_maxbytes) { - if (offset != file->f_pos) { - file->f_pos = offset; - file->f_version = 0; - } - retval = offset; - } - unlock_kernel(); - return retval; + mutex_lock(&file->f_dentry->d_inode->i_mutex); + rval = generic_file_llseek_unlocked(file, offset, origin); + mutex_unlock(&file->f_dentry->d_inode->i_mutex); + + return rval; } -EXPORT_SYMBOL(remote_llseek); +EXPORT_SYMBOL(generic_file_llseek); loff_t no_llseek(struct file *file, loff_t offset, int origin) { @@ -91,7 +97,7 @@ EXPORT_SYMBOL(no_llseek); loff_t default_llseek(struct file *file, loff_t offset, int origin) { - long long retval; + loff_t retval; lock_kernel(); switch (origin) { @@ -197,25 +203,27 @@ int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count { struct inode *inode; loff_t pos; + int retval = -EINVAL; inode = file->f_path.dentry->d_inode; if (unlikely((ssize_t) count < 0)) - goto Einval; + return retval; pos = *ppos; if (unlikely((pos < 0) || (loff_t) (pos + count) < 0)) - goto Einval; + return retval; if (unlikely(inode->i_flock && mandatory_lock(inode))) { - int retval = locks_mandatory_area( + retval = locks_mandatory_area( read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE, inode, file, pos, count); if (retval < 0) return retval; } + retval = security_file_permission(file, + read_write == READ ? MAY_READ : MAY_WRITE); + if (retval) + return retval; return count > MAX_RW_COUNT ? MAX_RW_COUNT : count; - -Einval: - return -EINVAL; } static void wait_on_retry_sync_kiocb(struct kiocb *iocb) @@ -267,18 +275,15 @@ ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) ret = rw_verify_area(READ, file, pos, count); if (ret >= 0) { count = ret; - ret = security_file_permission (file, MAY_READ); - if (!ret) { - if (file->f_op->read) - ret = file->f_op->read(file, buf, count, pos); - else - ret = do_sync_read(file, buf, count, pos); - if (ret > 0) { - fsnotify_access(file->f_path.dentry); - add_rchar(current, ret); - } - inc_syscr(current); + if (file->f_op->read) + ret = file->f_op->read(file, buf, count, pos); + else + ret = do_sync_read(file, buf, count, pos); + if (ret > 0) { + fsnotify_access(file->f_path.dentry); + add_rchar(current, ret); } + inc_syscr(current); } return ret; @@ -325,18 +330,15 @@ ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_ ret = rw_verify_area(WRITE, file, pos, count); if (ret >= 0) { count = ret; - ret = security_file_permission (file, MAY_WRITE); - if (!ret) { - if (file->f_op->write) - ret = file->f_op->write(file, buf, count, pos); - else - ret = do_sync_write(file, buf, count, pos); - if (ret > 0) { - fsnotify_modify(file->f_path.dentry); - add_wchar(current, ret); - } - inc_syscw(current); + if (file->f_op->write) + ret = file->f_op->write(file, buf, count, pos); + else + ret = do_sync_write(file, buf, count, pos); + if (ret > 0) { + fsnotify_modify(file->f_path.dentry); + add_wchar(current, ret); } + inc_syscw(current); } return ret; @@ -370,7 +372,6 @@ asmlinkage ssize_t sys_read(unsigned int fd, char __user * buf, size_t count) return ret; } -EXPORT_UNUSED_SYMBOL_GPL(sys_read); /* to be deleted for 2.6.25 */ asmlinkage ssize_t sys_write(unsigned int fd, const char __user * buf, size_t count) { @@ -450,6 +451,7 @@ unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) } return seg; } +EXPORT_SYMBOL(iov_shorten); ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn) @@ -603,9 +605,6 @@ static ssize_t do_readv_writev(int type, struct file *file, ret = rw_verify_area(type, file, pos, tot_len); if (ret < 0) goto out; - ret = security_file_permission(file, type == READ ? MAY_READ : MAY_WRITE); - if (ret) - goto out; fnv = NULL; if (type == READ) { @@ -737,10 +736,6 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, goto fput_in; count = retval; - retval = security_file_permission (in_file, MAY_READ); - if (retval) - goto fput_in; - /* * Get output file, and verify that it is ok.. */ @@ -759,10 +754,6 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, goto fput_out; count = retval; - retval = security_file_permission (out_file, MAY_WRITE); - if (retval) - goto fput_out; - if (!max) max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes);