|
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [MINIOS PATCH v3 06/12] use alloc_file_type() and get_file_from_fd() in blkfront
Juergen Gross, le dim. 16 janv. 2022 09:33:22 +0100, a ecrit:
> Allocate the file type dynamically via alloc_file_type().
>
> Instead of directly accessing the files[] array use get_file_from_fd().
>
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Reviewed-by: Samuel Thibault <samuel.thibault@xxxxxxxxxxxx>
> ---
> V3:
> - switch to struct file * parameter for callbacks
> - use __attribute__((constructor))
> ---
> blkfront.c | 92 ++++++++++++++++++++++++++++++++++------------
> include/blkfront.h | 5 ---
> include/lib.h | 3 +-
> lib/sys.c | 24 ------------
> 4 files changed, 69 insertions(+), 55 deletions(-)
>
> diff --git a/blkfront.c b/blkfront.c
> index e3f42bef..ed902702 100644
> --- a/blkfront.c
> +++ b/blkfront.c
> @@ -59,10 +59,10 @@ void blkfront_handler(evtchn_port_t port, struct pt_regs
> *regs, void *data)
> {
> #ifdef HAVE_LIBC
> struct blkfront_dev *dev = data;
> - int fd = dev->fd;
> + struct file *file = get_file_from_fd(dev->fd);
>
> - if (fd != -1)
> - files[fd].read = true;
> + if ( file )
> + file->read = true;
> #endif
> wake_up(&blkfront_queue);
> }
> @@ -483,9 +483,13 @@ int blkfront_aio_poll(struct blkfront_dev *dev)
>
> moretodo:
> #ifdef HAVE_LIBC
> - if (dev->fd != -1) {
> - files[dev->fd].read = false;
> - mb(); /* Make sure to let the handler set read to 1 before we start
> looking at the ring */
> + {
> + struct file *file = get_file_from_fd(dev->fd);
> +
> + if ( file ) {
> + file->read = false;
> + mb(); /* Make sure to let the handler set read to 1 before we
> start looking at the ring */
> + }
> }
> #endif
>
> @@ -554,22 +558,11 @@ moretodo:
> }
>
> #ifdef HAVE_LIBC
> -int blkfront_open(struct blkfront_dev *dev)
> +static int blkfront_posix_rwop(struct file *file, uint8_t *buf, size_t count,
> + bool write)
> {
> - /* Silently prevent multiple opens */
> - if(dev->fd != -1) {
> - return dev->fd;
> - }
> - dev->fd = alloc_fd(FTYPE_BLK);
> - printk("blk_open(%s) -> %d\n", dev->nodename, dev->fd);
> - files[dev->fd].dev = dev;
> - return dev->fd;
> -}
> -
> -int blkfront_posix_rwop(int fd, uint8_t* buf, size_t count, int write)
> -{
> - struct blkfront_dev* dev = files[fd].dev;
> - off_t offset = files[fd].offset;
> + struct blkfront_dev *dev = file->dev;
> + off_t offset = file->offset;
> struct blkfront_aiocb aiocb;
> unsigned long long disksize = dev->info.sectors * dev->info.sector_size;
> unsigned int blocksize = dev->info.sector_size;
> @@ -711,14 +704,24 @@ int blkfront_posix_rwop(int fd, uint8_t* buf, size_t
> count, int write)
> }
>
> free(copybuf);
> - files[fd].offset += rc;
> + file->offset += rc;
> return rc;
>
> }
>
> -int blkfront_posix_fstat(int fd, struct stat* buf)
> +static int blkfront_posix_read(struct file *file, void *buf, size_t nbytes)
> {
> - struct blkfront_dev* dev = files[fd].dev;
> + return blkfront_posix_rwop(file, buf, nbytes, false);
> +}
> +
> +static int blkfront_posix_write(struct file *file, const void *buf, size_t
> nbytes)
> +{
> + return blkfront_posix_rwop(file, (void *)buf, nbytes, true);
> +}
> +
> +static int blkfront_posix_fstat(struct file *file, struct stat *buf)
> +{
> + struct blkfront_dev *dev = file->dev;
>
> buf->st_mode = dev->info.mode;
> buf->st_uid = 0;
> @@ -728,4 +731,45 @@ int blkfront_posix_fstat(int fd, struct stat* buf)
>
> return 0;
> }
> +
> +static int blkfront_close_fd(struct file *file)
> +{
> + shutdown_blkfront(file->dev);
> +
> + return 0;
> +}
> +
> +static const struct file_ops blk_ops = {
> + .name = "blk",
> + .read = blkfront_posix_read,
> + .write = blkfront_posix_write,
> + .lseek = lseek_default,
> + .close = blkfront_close_fd,
> + .fstat = blkfront_posix_fstat,
> + .select_rd = select_read_flag,
> +};
> +
> +static unsigned int ftype_blk;
> +
> +__attribute__((constructor))
> +static void blkfron_initialize(void)
> +{
> + ftype_blk = alloc_file_type(&blk_ops);
> +}
> +
> +int blkfront_open(struct blkfront_dev *dev)
> +{
> + struct file *file;
> +
> + /* Silently prevent multiple opens */
> + if ( dev->fd != -1 )
> + return dev->fd;
> +
> + dev->fd = alloc_fd(ftype_blk);
> + printk("blk_open(%s) -> %d\n", dev->nodename, dev->fd);
> + file = get_file_from_fd(dev->fd);
> + file->dev = dev;
> +
> + return dev->fd;
> +}
> #endif
> diff --git a/include/blkfront.h b/include/blkfront.h
> index 3528af9d..7f84a0a2 100644
> --- a/include/blkfront.h
> +++ b/include/blkfront.h
> @@ -28,17 +28,12 @@ struct blkfront_info
> };
> struct blkfront_dev *init_blkfront(char *nodename, struct blkfront_info
> *info);
> #ifdef HAVE_LIBC
> -#include <sys/stat.h>
> /* POSIX IO functions:
> * use blkfront_open() to get a file descriptor to the block device
> * Don't use the other blkfront posix functions here directly, instead use
> * read(), write(), lseek() and fstat() on the file descriptor
> */
> int blkfront_open(struct blkfront_dev *dev);
> -int blkfront_posix_rwop(int fd, uint8_t* buf, size_t count, int write);
> -#define blkfront_posix_write(fd, buf, count) blkfront_posix_rwop(fd,
> (uint8_t*)buf, count, 1)
> -#define blkfront_posix_read(fd, buf, count) blkfront_posix_rwop(fd,
> (uint8_t*)buf, count, 0)
> -int blkfront_posix_fstat(int fd, struct stat* buf);
> #endif
> void blkfront_aio(struct blkfront_aiocb *aiocbp, int write);
> #define blkfront_aio_read(aiocbp) blkfront_aio(aiocbp, 0)
> diff --git a/include/lib.h b/include/lib.h
> index 9b7eaae7..2f472b00 100644
> --- a/include/lib.h
> +++ b/include/lib.h
> @@ -166,8 +166,7 @@ extern struct wait_queue_head event_queue;
> #define FTYPE_FB 6
> #define FTYPE_KBD 7
> #define FTYPE_TAP 8
> -#define FTYPE_BLK 9
> -#define FTYPE_N 10
> +#define FTYPE_N 9
> #define FTYPE_SPARE 16
>
> struct file {
> diff --git a/lib/sys.c b/lib/sys.c
> index 39f51980..90684335 100644
> --- a/lib/sys.c
> +++ b/lib/sys.c
> @@ -343,11 +343,6 @@ int read(int fd, void *buf, size_t nbytes)
> }
> return ret * sizeof(union xenfb_in_event);
> }
> -#endif
> -#ifdef CONFIG_BLKFRONT
> - case FTYPE_BLK: {
> - return blkfront_posix_read(fd, buf, nbytes);
> - }
> #endif
> default:
> break;
> @@ -392,10 +387,6 @@ int write(int fd, const void *buf, size_t nbytes)
> case FTYPE_TAP:
> netfront_xmit(files[fd].dev, (void*) buf, nbytes);
> return nbytes;
> -#endif
> -#ifdef CONFIG_BLKFRONT
> - case FTYPE_BLK:
> - return blkfront_posix_write(fd, buf, nbytes);
> #endif
> default:
> break;
> @@ -455,10 +446,6 @@ off_t lseek(int fd, off_t offset, int whence)
> return ops->lseek(file, offset, whence);
>
> switch(file->type) {
> -#ifdef CONFIG_BLKFRONT
> - case FTYPE_BLK:
> - break;
> -#endif
> case FTYPE_FILE:
> break;
> default:
> @@ -505,11 +492,6 @@ int close(int fd)
> shutdown_netfront(files[fd].dev);
> break;
> #endif
> -#ifdef CONFIG_BLKFRONT
> - case FTYPE_BLK:
> - shutdown_blkfront(files[fd].dev);
> - break;
> -#endif
> #ifdef CONFIG_KBDFRONT
> case FTYPE_KBD:
> shutdown_kbdfront(files[fd].dev);
> @@ -591,10 +573,6 @@ int fstat(int fd, struct stat *buf)
> buf->st_ctime = time(NULL);
> return 0;
> }
> -#ifdef CONFIG_BLKFRONT
> - case FTYPE_BLK:
> - return blkfront_posix_fstat(fd, buf);
> -#endif
> default:
> break;
> }
> @@ -710,7 +688,6 @@ static const char *const file_types[] = {
> [FTYPE_CONSOLE] = "console",
> [FTYPE_SOCKET] = "socket",
> [FTYPE_TAP] = "net",
> - [FTYPE_BLK] = "blk",
> [FTYPE_KBD] = "kbd",
> [FTYPE_FB] = "fb",
> };
> @@ -896,7 +873,6 @@ static int select_poll(int nfds, fd_set *readfds, fd_set
> *writefds, fd_set *exce
> FD_CLR(i, exceptfds);
> break;
> case FTYPE_TAP:
> - case FTYPE_BLK:
> case FTYPE_KBD:
> case FTYPE_FB:
> if (FD_ISSET(i, readfds)) {
> --
> 2.26.2
>
--
Samuel
After watching my newly-retired dad spend two weeks learning how to make a new
folder, it became obvious that "intuitive" mostly means "what the writer or
speaker of intuitive likes".
(Bruce Ediger, bediger@xxxxxxxxxxxx, in comp.os.linux.misc, on X the
intuitiveness of a Mac interface.)
|
 |
Lists.xenproject.org is hosted with RackSpace, monitoring our |