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authorLinus Torvalds <torvalds@linux-foundation.org>2015-04-15 13:49:27 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-15 13:49:27 -0700
commite44740c1a94b5d39b093045920f543a7bc135584 (patch)
tree3dc097e078653cc520476ac997e1765b90703a56 /fs/hostfs
parentd613896926be608796bb80454256a07b55fe0e87 (diff)
parentfe205bdd1321f95f8f3c35d243ea7cb22af8fbe1 (diff)
Merge tag 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger: - hostfs saw a face lifting - old/broken stuff was removed (SMP, HIGHMEM, SKAS3/4) - random cleanups and bug fixes * tag 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: (26 commits) um: Print minimum physical memory requirement um: Move uml_postsetup in the init_thread stack um: add a kmsg_dumper x86, UML: fix integer overflow in ELF_ET_DYN_BASE um: hostfs: Reduce number of syscalls in readdir um: Remove broken highmem support um: Remove broken SMP support um: Remove SKAS3/4 support um: Remove ppc cruft um: Remove ia64 cruft um: Remove dead code from stacktrace hostfs: No need to box and later unbox the file mode hostfs: Use page_offset() hostfs: Set page flags in hostfs_readpage() correctly hostfs: Remove superfluous initializations in hostfs_open() hostfs: hostfs_open: Reset open flags upon each retry hostfs: Remove superfluous test in hostfs_open() hostfs: Report append flag in ->show_options() hostfs: Use __getname() in follow_link hostfs: Remove open coded strcpy() ...
Diffstat (limited to 'fs/hostfs')
-rw-r--r--fs/hostfs/hostfs.h6
-rw-r--r--fs/hostfs/hostfs_kern.c112
-rw-r--r--fs/hostfs/hostfs_user.c29
3 files changed, 77 insertions, 70 deletions
diff --git a/fs/hostfs/hostfs.h b/fs/hostfs/hostfs.h
index 4fcd40d6f308..91e19f9dffe5 100644
--- a/fs/hostfs/hostfs.h
+++ b/fs/hostfs/hostfs.h
@@ -66,7 +66,8 @@ extern int stat_file(const char *path, struct hostfs_stat *p, int fd);
extern int access_file(char *path, int r, int w, int x);
extern int open_file(char *path, int r, int w, int append);
extern void *open_dir(char *path, int *err_out);
-extern char *read_dir(void *stream, unsigned long long *pos,
+extern void seek_dir(void *stream, unsigned long long pos);
+extern char *read_dir(void *stream, unsigned long long *pos_out,
unsigned long long *ino_out, int *len_out,
unsigned int *type_out);
extern void close_file(void *stream);
@@ -77,8 +78,7 @@ extern int write_file(int fd, unsigned long long *offset, const char *buf,
int len);
extern int lseek_file(int fd, long long offset, int whence);
extern int fsync_file(int fd, int datasync);
-extern int file_create(char *name, int ur, int uw, int ux, int gr,
- int gw, int gx, int or, int ow, int ox);
+extern int file_create(char *name, int mode);
extern int set_attr(const char *file, struct hostfs_iattr *attrs, int fd);
extern int make_symlink(const char *from, const char *to);
extern int unlink_file(const char *file);
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index e021188ca110..b83a0343378b 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -24,6 +24,7 @@ struct hostfs_inode_info {
int fd;
fmode_t mode;
struct inode vfs_inode;
+ struct mutex open_mutex;
};
static inline struct hostfs_inode_info *HOSTFS_I(struct inode *inode)
@@ -92,16 +93,22 @@ static char *__dentry_name(struct dentry *dentry, char *name)
__putname(name);
return NULL;
}
+
+ /*
+ * This function relies on the fact that dentry_path_raw() will place
+ * the path name at the end of the provided buffer.
+ */
+ BUG_ON(p + strlen(p) + 1 != name + PATH_MAX);
+
strlcpy(name, root, PATH_MAX);
if (len > p - name) {
__putname(name);
return NULL;
}
- if (p > name + len) {
- char *s = name + len;
- while ((*s++ = *p++) != '\0')
- ;
- }
+
+ if (p > name + len)
+ strcpy(name + len, p);
+
return name;
}
@@ -135,21 +142,19 @@ static char *follow_link(char *link)
int len, n;
char *name, *resolved, *end;
- len = 64;
- while (1) {
+ name = __getname();
+ if (!name) {
n = -ENOMEM;
- name = kmalloc(len, GFP_KERNEL);
- if (name == NULL)
- goto out;
-
- n = hostfs_do_readlink(link, name, len);
- if (n < len)
- break;
- len *= 2;
- kfree(name);
+ goto out_free;
}
+
+ n = hostfs_do_readlink(link, name, PATH_MAX);
if (n < 0)
goto out_free;
+ else if (n == PATH_MAX) {
+ n = -E2BIG;
+ goto out_free;
+ }
if (*name == '/')
return name;
@@ -168,13 +173,12 @@ static char *follow_link(char *link)
}
sprintf(resolved, "%s%s", link, name);
- kfree(name);
+ __putname(name);
kfree(link);
return resolved;
out_free:
- kfree(name);
- out:
+ __putname(name);
return ERR_PTR(n);
}
@@ -225,6 +229,7 @@ static struct inode *hostfs_alloc_inode(struct super_block *sb)
hi->fd = -1;
hi->mode = 0;
inode_init_once(&hi->vfs_inode);
+ mutex_init(&hi->open_mutex);
return &hi->vfs_inode;
}
@@ -257,6 +262,9 @@ static int hostfs_show_options(struct seq_file *seq, struct dentry *root)
if (strlen(root_path) > offset)
seq_printf(seq, ",%s", root_path + offset);
+ if (append)
+ seq_puts(seq, ",append");
+
return 0;
}
@@ -284,6 +292,7 @@ static int hostfs_readdir(struct file *file, struct dir_context *ctx)
if (dir == NULL)
return -error;
next = ctx->pos;
+ seek_dir(dir, next);
while ((name = read_dir(dir, &next, &ino, &len, &type)) != NULL) {
if (!dir_emit(ctx, name, len, ino, type))
break;
@@ -293,13 +302,12 @@ static int hostfs_readdir(struct file *file, struct dir_context *ctx)
return 0;
}
-static int hostfs_file_open(struct inode *ino, struct file *file)
+static int hostfs_open(struct inode *ino, struct file *file)
{
- static DEFINE_MUTEX(open_mutex);
char *name;
- fmode_t mode = 0;
+ fmode_t mode;
int err;
- int r = 0, w = 0, fd;
+ int r, w, fd;
mode = file->f_mode & (FMODE_READ | FMODE_WRITE);
if ((mode & HOSTFS_I(ino)->mode) == mode)
@@ -308,12 +316,12 @@ static int hostfs_file_open(struct inode *ino, struct file *file)
mode |= HOSTFS_I(ino)->mode;
retry:
+ r = w = 0;
+
if (mode & FMODE_READ)
r = 1;
if (mode & FMODE_WRITE)
- w = 1;
- if (w)
- r = 1;
+ r = w = 1;
name = dentry_name(file->f_path.dentry);
if (name == NULL)
@@ -324,15 +332,16 @@ retry:
if (fd < 0)
return fd;
- mutex_lock(&open_mutex);
+ mutex_lock(&HOSTFS_I(ino)->open_mutex);
/* somebody else had handled it first? */
if ((mode & HOSTFS_I(ino)->mode) == mode) {
- mutex_unlock(&open_mutex);
+ mutex_unlock(&HOSTFS_I(ino)->open_mutex);
+ close_file(&fd);
return 0;
}
if ((mode | HOSTFS_I(ino)->mode) != mode) {
mode |= HOSTFS_I(ino)->mode;
- mutex_unlock(&open_mutex);
+ mutex_unlock(&HOSTFS_I(ino)->open_mutex);
close_file(&fd);
goto retry;
}
@@ -342,12 +351,12 @@ retry:
err = replace_file(fd, HOSTFS_I(ino)->fd);
close_file(&fd);
if (err < 0) {
- mutex_unlock(&open_mutex);
+ mutex_unlock(&HOSTFS_I(ino)->open_mutex);
return err;
}
}
HOSTFS_I(ino)->mode = mode;
- mutex_unlock(&open_mutex);
+ mutex_unlock(&HOSTFS_I(ino)->open_mutex);
return 0;
}
@@ -382,7 +391,7 @@ static const struct file_operations hostfs_file_fops = {
.read_iter = generic_file_read_iter,
.write_iter = generic_file_write_iter,
.mmap = generic_file_mmap,
- .open = hostfs_file_open,
+ .open = hostfs_open,
.release = hostfs_file_release,
.fsync = hostfs_fsync,
};
@@ -391,6 +400,8 @@ static const struct file_operations hostfs_dir_fops = {
.llseek = generic_file_llseek,
.iterate = hostfs_readdir,
.read = generic_read_dir,
+ .open = hostfs_open,
+ .fsync = hostfs_fsync,
};
static int hostfs_writepage(struct page *page, struct writeback_control *wbc)
@@ -398,7 +409,7 @@ static int hostfs_writepage(struct page *page, struct writeback_control *wbc)
struct address_space *mapping = page->mapping;
struct inode *inode = mapping->host;
char *buffer;
- unsigned long long base;
+ loff_t base = page_offset(page);
int count = PAGE_CACHE_SIZE;
int end_index = inode->i_size >> PAGE_CACHE_SHIFT;
int err;
@@ -407,7 +418,6 @@ static int hostfs_writepage(struct page *page, struct writeback_control *wbc)
count = inode->i_size & (PAGE_CACHE_SIZE-1);
buffer = kmap(page);
- base = ((unsigned long long) page->index) << PAGE_CACHE_SHIFT;
err = write_file(HOSTFS_I(inode)->fd, &base, buffer, count);
if (err != count) {
@@ -432,26 +442,29 @@ static int hostfs_writepage(struct page *page, struct writeback_control *wbc)
static int hostfs_readpage(struct file *file, struct page *page)
{
char *buffer;
- long long start;
- int err = 0;
+ loff_t start = page_offset(page);
+ int bytes_read, ret = 0;
- start = (long long) page->index << PAGE_CACHE_SHIFT;
buffer = kmap(page);
- err = read_file(FILE_HOSTFS_I(file)->fd, &start, buffer,
+ bytes_read = read_file(FILE_HOSTFS_I(file)->fd, &start, buffer,
PAGE_CACHE_SIZE);
- if (err < 0)
+ if (bytes_read < 0) {
+ ClearPageUptodate(page);
+ SetPageError(page);
+ ret = bytes_read;
goto out;
+ }
- memset(&buffer[err], 0, PAGE_CACHE_SIZE - err);
+ memset(buffer + bytes_read, 0, PAGE_CACHE_SIZE - bytes_read);
- flush_dcache_page(page);
+ ClearPageError(page);
SetPageUptodate(page);
- if (PageError(page)) ClearPageError(page);
- err = 0;
+
out:
+ flush_dcache_page(page);
kunmap(page);
unlock_page(page);
- return err;
+ return ret;
}
static int hostfs_write_begin(struct file *file, struct address_space *mapping,
@@ -528,11 +541,13 @@ static int read_name(struct inode *ino, char *name)
init_special_inode(ino, st.mode & S_IFMT, rdev);
ino->i_op = &hostfs_iops;
break;
-
- default:
+ case S_IFREG:
ino->i_op = &hostfs_iops;
ino->i_fop = &hostfs_file_fops;
ino->i_mapping->a_ops = &hostfs_aops;
+ break;
+ default:
+ return -EIO;
}
ino->i_ino = st.ino;
@@ -566,10 +581,7 @@ static int hostfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
if (name == NULL)
goto out_put;
- fd = file_create(name,
- mode & S_IRUSR, mode & S_IWUSR, mode & S_IXUSR,
- mode & S_IRGRP, mode & S_IWGRP, mode & S_IXGRP,
- mode & S_IROTH, mode & S_IWOTH, mode & S_IXOTH);
+ fd = file_create(name, mode & S_IFMT);
if (fd < 0)
error = fd;
else
diff --git a/fs/hostfs/hostfs_user.c b/fs/hostfs/hostfs_user.c
index 9765dab95cbd..9c1e0f019880 100644
--- a/fs/hostfs/hostfs_user.c
+++ b/fs/hostfs/hostfs_user.c
@@ -97,21 +97,27 @@ void *open_dir(char *path, int *err_out)
return dir;
}
-char *read_dir(void *stream, unsigned long long *pos,
+void seek_dir(void *stream, unsigned long long pos)
+{
+ DIR *dir = stream;
+
+ seekdir(dir, pos);
+}
+
+char *read_dir(void *stream, unsigned long long *pos_out,
unsigned long long *ino_out, int *len_out,
unsigned int *type_out)
{
DIR *dir = stream;
struct dirent *ent;
- seekdir(dir, *pos);
ent = readdir(dir);
if (ent == NULL)
return NULL;
*len_out = strlen(ent->d_name);
*ino_out = ent->d_ino;
*type_out = ent->d_type;
- *pos = telldir(dir);
+ *pos_out = ent->d_off;
return ent->d_name;
}
@@ -175,21 +181,10 @@ void close_dir(void *stream)
closedir(stream);
}
-int file_create(char *name, int ur, int uw, int ux, int gr,
- int gw, int gx, int or, int ow, int ox)
+int file_create(char *name, int mode)
{
- int mode, fd;
-
- mode = 0;
- mode |= ur ? S_IRUSR : 0;
- mode |= uw ? S_IWUSR : 0;
- mode |= ux ? S_IXUSR : 0;
- mode |= gr ? S_IRGRP : 0;
- mode |= gw ? S_IWGRP : 0;
- mode |= gx ? S_IXGRP : 0;
- mode |= or ? S_IROTH : 0;
- mode |= ow ? S_IWOTH : 0;
- mode |= ox ? S_IXOTH : 0;
+ int fd;
+
fd = open64(name, O_CREAT | O_RDWR, mode);
if (fd < 0)
return -errno;