Orion
Barry Adding pipes e59e4fe (2 years, 7 months ago)diff --git a/vfs/ext2fs/block.c b/vfs/ext2fs/block.c
index 28cf480..08f2185 100644
--- a/vfs/ext2fs/block.c
+++ b/vfs/ext2fs/block.c
@@ -23,10 +23,32 @@ ext2_get_data_addr(SuperBlock *super, Ext2Inode *node, uint32_t index)
{
uint32_t tmp;
char block[4096];
+ Ext2Super *rsuper = super->data;
+ /* Blocks per indirect block */
+ uint32_t bpib = (1024 << rsuper->blockSize) / sizeof(uint32_t);
/* Main blocks */
if (index < 12)
return node->directBlock[index];
index -= 12;
+
+ /* Single indirect block */
+ if (index < bpib) {
+ ext2_read_block(super, node->singleBlock, block);
+ return *((uint32_t *) block + index);
+ }
+ index -= bpib;
+
+ /* Double indirect block */
+ if (index < bpib*bpib) {
+ panic("Attempt to read from double indirect block");
+ }
+ index -= bpib*bpib;
+
+ /* Triple indirect block */
+ if (index < bpib*bpib*bpib) {
+ panic("Attempt to read from triple indirect block");
+ }
+
return 0;
}
diff --git a/vfs/file.c b/vfs/file.c
index d3dfdc6..33fd0b7 100644
--- a/vfs/file.c
+++ b/vfs/file.c
@@ -30,6 +30,8 @@ file_put(File *file)
ASSERT(file->usage);
if (--file->usage)
return;
+ if (file->ops && file->ops->release)
+ file->ops->release(file);
if (file->inode)
inode_put(file->inode);
if (file->path)
diff --git a/vfs/inode.c b/vfs/inode.c
index 34b5c65..50d6200 100644
--- a/vfs/inode.c
+++ b/vfs/inode.c
@@ -58,6 +58,8 @@ inode_put(Inode *inode)
}
/* Clean up */
+ if (inode->free_extra)
+ inode->free_extra(inode);
if (S_ISDIR(inode->mode))
entry_clean(inode);
else
diff --git a/vfs/pipe.c b/vfs/pipe.c
new file mode 100644
index 0000000..0566597
--- /dev/null
+++ b/vfs/pipe.c
@@ -0,0 +1,234 @@
+/*
+ * This file implements the VFS pipe mechanism. It supports both named and
+ * anonymous pipes (FIFOs and pipes), and uses the same underlying operations
+ * for both. It uses a ring buffer to implement the reading/writing.
+ */
+
+#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
+#include <errno.h>
+#include "vfs.h"
+#include "cache.h"
+#include "inode.h"
+#include "../mem/heap.h"
+#include "../mem/paging.h"
+#include "../mem/frame.h"
+#include "../task/task.h"
+
+/* Structure for pipe data */
+typedef struct Pipe {
+ size_t size;
+ off_t head, tail;
+ size_t readers, writers;
+ TaskQueue readQueue, writeQueue;
+} Pipe;
+
+size_t pipe_read(File *file, char *buf, size_t size, off_t offset);
+size_t pipe_write(File *file, char *buf, size_t size, off_t offset);
+int pipe_release(File *file);
+
+FileOps pipeWriteFileOps = {
+ .write = pipe_write,
+ .release = pipe_release,
+};
+FileOps pipeReadFileOps = {
+ .read = pipe_read,
+ .release = pipe_release,
+};
+
+/* Free a Pipe */
+static void
+pipe_free_extra(Inode *inode)
+{
+ Pipe *pipe = inode->extra;
+
+ /* Resume waiting tasks */
+ Task *task;
+ while ((task = pop_from_queue(&pipe->readQueue)) != NULL) {
+ unblock_task(task);
+ send_sig(task, SIGPIPE);
+ }
+ while ((task = pop_from_queue(&pipe->writeQueue)) != NULL) {
+ unblock_task(task);
+ send_sig(task, SIGPIPE);
+ }
+}
+
+/* Open an anonymous pipe */
+int
+pipe(int pipefd[2])
+{
+ if (!verify_access(pipefd, sizeof(int) * 2, PROT_WRITE))
+ return -EFAULT;
+
+ /* Allocate file descriptors */
+ int freefd = 0, i;
+ for (i = 0; i < NFILES; i++)
+ freefd += !current->files->fd[i];
+ if (freefd < 2)
+ return -EMFILE;
+
+ /* Create endpoints */
+ File *file[2];
+ Pipe *pipe = kmalloc(sizeof(Pipe));
+ Inode *inode = kmalloc(sizeof(Inode));
+ for (i = 0; i < 2; i++) {
+ file[i] = kmalloc(sizeof(File));
+
+ /* Install file descriptors */
+ for (pipefd[i] = 0; pipefd[i] < NFILES; pipefd[i]++)
+ if (!current->files->fd[pipefd[i]])
+ break;
+ current->files->fd[pipefd[i]] = file[i];
+
+ /* Build files */
+ file[i]->inode = inode_get(inode);
+ file[i]->mode = S_IFIFO | 0666;
+ file[i]->uid = current->uid;
+ file[i]->gid = current->gid;
+ file[i]->usage = 1;
+ }
+ file[0]->ops = &pipeReadFileOps;
+ file[1]->ops = &pipeWriteFileOps;
+ inode->extra = pipe;
+ pipe->readers = pipe->writers = 1;
+ page_create(inode, alloc_frames(1), 0);
+}
+
+/* Read from a pipe */
+size_t
+pipe_read(File *file, char *buf, size_t size, off_t offset)
+{
+ offset %= 4096;
+
+ Pipe *pipe = file->inode->extra;
+ if (!pipe->writers) {
+ send_sig(current, SIGPIPE);
+ return 0;
+ }
+
+ Task *tmp;
+ Page *page = page_find(file->inode, 0);
+ acquire(&quickPageLock);
+ page_t oldPage = quick_page(page->frame);
+ size_t count = 0, avail, min, minPart;
+ while (size) {
+ avail = pipe->size;
+ if (!avail) {
+ quick_page(oldPage);
+ release(&quickPageLock);
+
+ if (!pipe->writers)
+ goto end;
+
+ while (tmp = pop_from_queue(&pipe->writeQueue))
+ unblock_task(tmp);
+ add_to_queue(&pipe->readQueue, current);
+ block_task(WAITING_FOR_IO);
+
+ acquire(&quickPageLock);
+ oldPage = quick_page(page->frame);
+ }
+ avail = pipe->size;
+ min = (size < avail) ? size : avail;
+ if (pipe->tail + min >= 4096) {
+ minPart = 4096 - pipe->tail;
+ memcpy(buf + count, QUICK_PAGE + pipe->tail, minPart);
+ memcpy(buf + count + minPart, QUICK_PAGE,
+ min - minPart);
+ } else {
+ memcpy(buf + count, QUICK_PAGE + pipe->tail, min);
+ }
+
+ size -= min;
+ count += min;
+ pipe->tail += min;
+ pipe->tail %= 4096;
+ pipe->size -= min;
+ }
+
+ quick_page(oldPage);
+ release(&quickPageLock);
+
+end:
+ while (tmp = pop_from_queue(&pipe->writeQueue))
+ unblock_task(tmp);
+
+ return count;
+}
+
+/* Write to a pipe */
+size_t
+pipe_write(File *file, char *buf, size_t size, off_t offset)
+{
+ offset %= 4096;
+
+ Pipe *pipe = file->inode->extra;
+ if (!pipe->readers) {
+ send_sig(current, SIGPIPE);
+ return 0;
+ }
+
+ Task *tmp;
+ Page *page = page_find(file->inode, 0);
+ acquire(&quickPageLock);
+ page_t oldPage = quick_page(page->frame);
+ size_t count = 0, space, min, minPart;
+ while (size) {
+ space = 4096 - pipe->size;
+ if (!space) {
+ quick_page(oldPage);
+ release(&quickPageLock);
+
+ while (tmp = pop_from_queue(&pipe->readQueue))
+ unblock_task(tmp);
+ add_to_queue(&pipe->writeQueue, current);
+ block_task(WAITING_FOR_IO);
+
+ acquire(&quickPageLock);
+ oldPage = quick_page(page->frame);
+ }
+ space = 4096 - pipe->size;
+ min = (size < space) ? size : space;
+ if (pipe->head + min >= 4096) {
+ minPart = 4096 - pipe->head;
+ memcpy(QUICK_PAGE + pipe->head, buf + count, minPart);
+ memcpy(QUICK_PAGE, buf + count + minPart,
+ min - minPart);
+ } else {
+ memcpy(QUICK_PAGE + pipe->head, buf + count, min);
+ }
+
+ size -= min;
+ count += min;
+ pipe->head += min;
+ pipe->head %= 4096;
+ pipe->size += min;
+ }
+
+ quick_page(oldPage);
+ release(&quickPageLock);
+
+ while (tmp = pop_from_queue(&pipe->readQueue))
+ unblock_task(tmp);
+
+ return count;
+}
+
+int
+pipe_release(File *file)
+{
+ Task *tmp;
+ Pipe *pipe = file->inode->extra;
+ TaskQueue *queue = (file->ops == &pipeReadFileOps)
+ ? &pipe->writeQueue : &pipe->readQueue;
+ while (tmp = pop_from_queue(queue)) {
+ unblock_task(tmp);
+ send_sig(tmp, SIGPIPE);
+ }
+ if (queue == &pipe->readQueue)
+ pipe->writers--;
+ else
+ pipe->readers--;
+}
diff --git a/vfs/tmpfs/file.c b/vfs/tmpfs/file.c
index 252c88f..bc320ed 100644
--- a/vfs/tmpfs/file.c
+++ b/vfs/tmpfs/file.c
@@ -33,7 +33,7 @@ tmpfs_read(File *file, char *buf, size_t size, off_t offset)
if (size + offset > file->inode->size)
size = file->inode->size - offset;
- uint16_t min;
+ uint16_t min, indent = offset % 4096;
size_t count = 0;
Page *page;
page_t oldPage;
@@ -44,11 +44,12 @@ tmpfs_read(File *file, char *buf, size_t size, off_t offset)
break;
acquire(&quickPageLock);
oldPage = quick_page(page->frame);
- memcpy(buf + count, QUICK_PAGE, min);
+ memcpy(buf + count, QUICK_PAGE + indent, min);
quick_page(oldPage);
release(&quickPageLock);
size -= min;
count += min;
+ indent = 0;
}
return count;
}
@@ -60,7 +61,7 @@ tmpfs_write(File *file, char *buf, size_t size, off_t offset)
if (size + offset > file->inode->size)
file->inode->size = size + offset;
- uint16_t min;
+ uint16_t min, indent = offset % 4096;
size_t count = 0;
Page *page;
page_t oldPage;
@@ -72,11 +73,12 @@ tmpfs_write(File *file, char *buf, size_t size, off_t offset)
offset);
acquire(&quickPageLock);
oldPage = quick_page(page->frame);
- memcpy(QUICK_PAGE, buf + count, min);
+ memcpy(QUICK_PAGE + indent, buf + count, min);
quick_page(oldPage);
release(&quickPageLock);
size -= min;
count += min;
+ indent = 0;
}
return count;
}
diff --git a/vfs/vfs.c b/vfs/vfs.c
index 68f4b34..c4784f2 100644
--- a/vfs/vfs.c
+++ b/vfs/vfs.c
@@ -322,7 +322,7 @@ close(int fd)
}
/* Read a file */
-size_t
+int
read(int fd, void *buf, size_t count)
{
if (!verify_access(buf, count, PROT_WRITE))
@@ -336,11 +336,12 @@ read(int fd, void *buf, size_t count)
if (S_ISDIR(file->mode))
return -EISDIR;
- return file_read(file, buf, count);
+ int sz = (int) file_read(file, buf, count);
+ return sz;
}
/* Write a file */
-size_t
+int
write(int fd, void *buf, size_t count)
{
if (!verify_access(buf, count, PROT_READ))
@@ -354,7 +355,8 @@ write(int fd, void *buf, size_t count)
if (S_ISDIR(file->mode))
return -EISDIR;
- return file_write(file, buf, count);
+ int sz = (int) file_write(file, buf, count);
+ return sz;
}
/* I/O Control */
@@ -414,12 +416,13 @@ stat(const char *pathname, struct stat *statbuf)
if (!inode)
return -ENOENT;
if (statbuf) {
- statbuf->inode = inode->ino;
- statbuf->mode = inode->mode;
- statbuf->nlink = inode->nlink;
- statbuf->uid = inode->uid;
- statbuf->gid = inode->gid;
- statbuf->size = inode->size;
+ statbuf->st_dev = inode->dev;
+ statbuf->st_ino = inode->ino;
+ statbuf->st_mode = inode->mode;
+ statbuf->st_nlink = inode->nlink;
+ statbuf->st_uid = inode->uid;
+ statbuf->st_gid = inode->gid;
+ statbuf->st_size = inode->size;
}
inode_put(inode);
return 0;
@@ -437,9 +440,15 @@ fstat(int fd, struct stat *statbuf)
if (!file)
return -EBADF;
Inode *inode = file->inode;
- statbuf->inode = inode->ino;
- statbuf->mode = inode->mode;
- statbuf->size = inode->size;
+ if (statbuf) {
+ statbuf->st_dev = inode->dev;
+ statbuf->st_ino = inode->ino;
+ statbuf->st_mode = inode->mode;
+ statbuf->st_nlink = inode->nlink;
+ statbuf->st_uid = inode->uid;
+ statbuf->st_gid = inode->gid;
+ statbuf->st_size = inode->size;
+ }
return 0;
}
diff --git a/vfs/vfs.h b/vfs/vfs.h
index ece5679..6997bf3 100644
--- a/vfs/vfs.h
+++ b/vfs/vfs.h
@@ -68,12 +68,14 @@ struct Inode {
Spinlock lock;
InodeOps *ops;
FileOps *fileOps;
+ void *extra;
+ void (*free_extra)(Inode *);
SuperBlock *super;
union {
DirEntry *dirEntries; /* List of Directory Entries */
PageCache *pages; /* List of Pages */
};
- Inode *lnext; /* Next inode in super list */
+ Inode *lnext; /* Next inode in super's list */
};
struct InodeOps {
int (*create)(Inode *, DirEntry *, mode_t);
@@ -163,8 +165,8 @@ Inode *lookup(const char *name, CustodyChain *chain);
int open(const char *name, int flags, ...); /* mode_t mode */
int close(int fd);
-size_t read(int fd, void *buf, size_t count);
-size_t write(int fd, void *buf, size_t count);
+int read(int fd, void *buf, size_t count);
+int write(int fd, void *buf, size_t count);
int ioctl(int fd, unsigned long request, ...);
off_t lseek(int fd, off_t offset, int whence);
int stat(const char *pathname, struct stat *statbuf);
@@ -175,6 +177,7 @@ int mknod(const char *pathname, mode_t mode, dev_t dev);
int rename(const char *oldpath, const char *newpath);
int dup(int oldfd);
int dup2(int oldfd, int newfd);
+int pipe(int pipefd[2]);
int mount(const char *src, const char *target, const char *type,
unsigned long flags, void *data);
int chdir(const char *path);