In the PDMA case the last transfer from the device to the FIFO has occurred
(async_len is zero) but esp_do_dma() is still being called to drain the
remaining FIFO contents.
The additional non-zero transfer check ensures that we still defer the SCSI
layer in the case where we are waiting for data for a TI command or a DMA
enable signal.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Tested-by: Helge Deller <deller@gmx.de>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20240112125420.514425-35-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
There are two cases here: the first is when the TI command underflows, in which
case we raise INTR_BS to indicate an early change of phase, and the second is
when the TI command overflows because the host requested a transfer for more
data than is available. In the latter case force TC to zero so that the TI
completion logic executes correctly.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Tested-by: Helge Deller <deller@gmx.de>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20240112125420.514425-30-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Ensure that the async_len checks for requesting data from the SCSI layer and
the TC == 0 checks to detect the end of the DMA transfer are consistent in both
do_dma_pdma_cb() and esp_do_dma(). In particular this involves adding the check
to see if the FIFO is at its low threshold since PDMA and mixed DMA and non-DMA
requests can leave data remaining in the FIFO.
At the same time update all the comments so that they are also consistent between
all similar code paths.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Tested-by: Helge Deller <deller@gmx.de>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20240112125420.514425-29-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
The fifo8_pop_buf() function returns a pointer to the FIFO buffer up to the
specified length. Since the FIFO buffer is modelled as an array then once
the FIFO wraps around, only the continuous portion of the buffer can be
returned.
In future the use of continuous and unaligned accesses will advance the
internal FIFO head pointer, so modify esp_fifo_pop_buf() to ensure that
any wraparound content is also returned up to the requested length.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Tested-by: Helge Deller <deller@gmx.de>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20240112125420.514425-4-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
As of commit 38738f7dbb ("virtio-scsi:
don't waste CPU polling the event virtqueue"), we only attach an io_read
notifier for the virtio-scsi event virtqueue instead, and no polling
notifiers. During operation, the event virtqueue is typically
non-empty, but none of the buffers are intended to be used immediately.
Instead, they only get used when certain events occur. Therefore, it
makes no sense to continuously poll it when non-empty, because it is
supposed to be and stay non-empty.
We do this by using virtio_queue_aio_attach_host_notifier_no_poll()
instead of virtio_queue_aio_attach_host_notifier() for the event
virtqueue.
Commit 766aa2de0f ("virtio-scsi: implement
BlockDevOps->drained_begin()") however has virtio_scsi_drained_end() use
virtio_queue_aio_attach_host_notifier() for all virtqueues, including
the event virtqueue. This can lead to it being polled again, undoing
the benefit of commit 38738f7dbb.
Fix it by using virtio_queue_aio_attach_host_notifier_no_poll() for the
event virtqueue.
Reported-by: Fiona Ebner <f.ebner@proxmox.com>
Fixes: 766aa2de0f
("virtio-scsi: implement BlockDevOps->drained_begin()")
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Fiona Ebner <f.ebner@proxmox.com>
Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-ID: <20240202153158.788922-2-hreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
usb-storage is for the most part just a wrapper around an internally
created scsi-disk device. It uses DEFINE_BLOCK_PROPERTIES() to offer all
of the usual block device properties to the user, but then only forwards
a few select properties to the internal device while the rest is
silently ignored.
This changes scsi_bus_legacy_add_drive() to accept a whole BlockConf
instead of some individual values inside of it so that usb-storage can
now pass the whole configuration to the internal scsi-disk. This enables
the remaining block device properties, e.g. logical/physical_block_size
or discard_granularity.
Buglink: https://issues.redhat.com/browse/RHEL-22375
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20240131130607.24117-1-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
scsi_device_for_each_req_async() currently does not provide any way to
be awaited. One of its callers is scsi_device_purge_requests(), which
therefore currently does not guarantee that all requests are fully
settled when it returns.
We want all requests to be settled, because scsi_device_purge_requests()
is called through the unrealize path, including the one invoked by
virtio_scsi_hotunplug() through qdev_simple_device_unplug_cb(), which
most likely assumes that all SCSI requests are done then.
In fact, scsi_device_purge_requests() already contains a blk_drain(),
but this will not fully await scsi_device_for_each_req_async(), only the
I/O requests it potentially cancels (not the non-I/O requests).
However, we can have scsi_device_for_each_req_async() increment the BB
in-flight counter, and have scsi_device_for_each_req_async_bh()
decrement it when it is done. This way, the blk_drain() will fully
await all SCSI requests to be purged.
This also removes the need for scsi_device_for_each_req_async_bh() to
double-check the current context and potentially re-schedule itself,
should it now differ from the BB's context: Changing a BB's AioContext
with a root node is done through bdrv_try_change_aio_context(), which
creates a drained section. With this patch, we keep the BB in-flight
counter elevated throughout, so we know the BB's context cannot change.
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-ID: <20240202144755.671354-3-hreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When the maximum count of SCRIPTS instructions is reached, the code
stops execution and returns, but fails to decrement the reentrancy
counter. This effectively renders the SCSI controller unusable
because on next entry the reentrancy counter is still above the limit.
This bug was seen on HP-UX 10.20 which seems to trigger SCRIPTS
loops.
Fixes: b987718bbb ("hw/scsi/lsi53c895a: Fix reentrancy issues in the LSI controller (CVE-2023-0330)")
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Message-ID: <20240128202214.2644768-1-svens@stackframe.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Even though the BLAST command isn't fully implemented in QEMU, the DMA_STAT_BCMBLT
bit should be set after the command has been issued to indicate that the command
has completed.
This fixes an issue with the DC390 DOS driver which issues the BLAST command as
part of its normal error recovery routine at startup, and otherwise sits in a
tight loop waiting for DMA_STAT_BCMBLT to be set before continuing.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Message-ID: <20240112131529.515642-5-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
The setting of DMA_STAT_DONE at the end of a DMA transfer can be configured to
generate an interrupt, however the Linux driver manually checks for DMA_STAT_DONE
being set and if it is, considers that a DMA transfer has completed.
If DMA_STAT_DONE is set but the ESP device isn't indicating an interrupt then
the Linux driver considers this to be a spurious interrupt. However this can
occur in QEMU as there is a delay between the end of DMA transfer where
DMA_STAT_DONE is set, and the ESP device raising its completion interrupt.
This appears to be an incorrect assumption in the Linux driver as the ESP and
PCI DMA interrupt sources are separate (and may not be raised exactly
together), however we can work around this by synchronising the setting of
DMA_STAT_DONE at the end of a DMA transfer with the ESP completion interrupt.
In conjunction with the previous commit Linux is now able to correctly boot
from an am53c974 PCI SCSI device on the hppa C3700 machine without emitting
"iget: checksum invalid" and "Spurious irq, sreg=10" errors.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Message-ID: <20240112131529.515642-4-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
The am53c974/dc390 PCI interrupt has two separate sources: the first is from the
internal ESP device, and the second is from the PCI DMA transfer logic.
Update the ESP interrupt handler so that it sets DMA_STAT_SCSIINT rather than
driving the PCI IRQ directly, and introduce a new esp_pci_update_irq() function
to generate the correct PCI IRQ level. In particular this fixes spurious interrupts
being generated by setting DMA_STAT_DONE at the end of a transfer if DMA_CMD_INTE_D
isn't set in the DMA_CMD register.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Message-ID: <20240112131529.515642-3-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
The current code in esp_pci_dma_memory_rw() sets the DMA address to the value
of the DMA_SPA (Starting Physical Address) register which is incorrect: this
means that for each callback from the SCSI layer the DMA address is set back
to the starting address.
In the case where only a single SCSI callback occurs (currently for transfer
lengths < 128kB) this works fine, however for larger transfers the DMA address
wraps back to the initial starting address, corrupting the buffer holding the
data transferred to the guest.
Fix esp_pci_dma_memory_rw() to use the DMA_WAC (Working Address Counter) for
the DMA address which is correctly incremented across multiple SCSI layer
transfers.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Message-ID: <20240112131529.515642-2-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Add a 'current_lun' check for a null value
to avoid null pointer dereferencing and
recover host if NULL return
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 4eb8606560 (esp: store lun coming from the MESSAGE OUT phase)
Signed-off-by: Alexandra Diupina <adiupina@astralinux.ru>
Message-ID: <20231229152647.19699-1-adiupina@astralinux.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
