| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Alexander Shishkin | 8375 | 98.46% | 32 | 74.42% |
| Shaokun Zhang | 92 | 1.08% | 1 | 2.33% |
| Colin Ian King | 12 | 0.14% | 2 | 4.65% |
| Wei Yongjun | 7 | 0.08% | 1 | 2.33% |
| Laura Abbott | 6 | 0.07% | 1 | 2.33% |
| Laurent FERT | 5 | 0.06% | 2 | 4.65% |
| Dave Jiang | 4 | 0.05% | 1 | 2.33% |
| Dan Carpenter | 3 | 0.04% | 1 | 2.33% |
| Souptick Joarder | 1 | 0.01% | 1 | 2.33% |
| JoonSoo Kim | 1 | 0.01% | 1 | 2.33% |
| Total | 8506 | 43 |
// SPDX-License-Identifier: GPL-2.0 /* * Intel(R) Trace Hub Memory Storage Unit * * Copyright (C) 2014-2015 Intel Corporation. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/types.h> #include <linux/module.h> #include <linux/device.h> #include <linux/uaccess.h> #include <linux/sizes.h> #include <linux/printk.h> #include <linux/slab.h> #include <linux/mm.h> #include <linux/fs.h> #include <linux/io.h> #include <linux/workqueue.h> #include <linux/dma-mapping.h> #ifdef CONFIG_X86 #include <asm/set_memory.h> #endif #include <linux/intel_th.h> #include "intel_th.h" #include "msu.h" #define msc_dev(x) (&(x)->thdev->dev) /* * Lockout state transitions: * READY -> INUSE -+-> LOCKED -+-> READY -> etc. * \-----------/ * WIN_READY: window can be used by HW * WIN_INUSE: window is in use * WIN_LOCKED: window is filled up and is being processed by the buffer * handling code * * All state transitions happen automatically, except for the LOCKED->READY, * which needs to be signalled by the buffer code by calling * intel_th_msc_window_unlock(). * * When the interrupt handler has to switch to the next window, it checks * whether it's READY, and if it is, it performs the switch and tracing * continues. If it's LOCKED, it stops the trace. */ enum lockout_state { WIN_READY = 0, WIN_INUSE, WIN_LOCKED }; /** * struct msc_window - multiblock mode window descriptor * @entry: window list linkage (msc::win_list) * @pgoff: page offset into the buffer that this window starts at * @lockout: lockout state, see comment below * @lo_lock: lockout state serialization * @nr_blocks: number of blocks (pages) in this window * @nr_segs: number of segments in this window (<= @nr_blocks) * @_sgt: array of block descriptors * @sgt: array of block descriptors */ struct msc_window { struct list_head entry; unsigned long pgoff; enum lockout_state lockout; spinlock_t lo_lock; unsigned int nr_blocks; unsigned int nr_segs; struct msc *msc; struct sg_table _sgt; struct sg_table *sgt; }; /** * struct msc_iter - iterator for msc buffer * @entry: msc::iter_list linkage * @msc: pointer to the MSC device * @start_win: oldest window * @win: current window * @offset: current logical offset into the buffer * @start_block: oldest block in the window * @block: block number in the window * @block_off: offset into current block * @wrap_count: block wrapping handling * @eof: end of buffer reached */ struct msc_iter { struct list_head entry; struct msc *msc; struct msc_window *start_win; struct msc_window *win; unsigned long offset; struct scatterlist *start_block; struct scatterlist *block; unsigned int block_off; unsigned int wrap_count; unsigned int eof; }; /** * struct msc - MSC device representation * @reg_base: register window base address * @thdev: intel_th_device pointer * @mbuf: MSU buffer, if assigned * @mbuf_priv MSU buffer's private data, if @mbuf * @win_list: list of windows in multiblock mode * @single_sgt: single mode buffer * @cur_win: current window * @nr_pages: total number of pages allocated for this buffer * @single_sz: amount of data in single mode * @single_wrap: single mode wrap occurred * @base: buffer's base pointer * @base_addr: buffer's base address * @user_count: number of users of the buffer * @mmap_count: number of mappings * @buf_mutex: mutex to serialize access to buffer-related bits * @enabled: MSC is enabled * @wrap: wrapping is enabled * @mode: MSC operating mode * @burst_len: write burst length * @index: number of this MSC in the MSU */ struct msc { void __iomem *reg_base; void __iomem *msu_base; struct intel_th_device *thdev; const struct msu_buffer *mbuf; void *mbuf_priv; struct work_struct work; struct list_head win_list; struct sg_table single_sgt; struct msc_window *cur_win; struct msc_window *switch_on_unlock; unsigned long nr_pages; unsigned long single_sz; unsigned int single_wrap : 1; void *base; dma_addr_t base_addr; u32 orig_addr; u32 orig_sz; /* <0: no buffer, 0: no users, >0: active users */ atomic_t user_count; atomic_t mmap_count; struct mutex buf_mutex; struct list_head iter_list; bool stop_on_full; /* config */ unsigned int enabled : 1, wrap : 1, do_irq : 1, multi_is_broken : 1; unsigned int mode; unsigned int burst_len; unsigned int index; }; static LIST_HEAD(msu_buffer_list); static DEFINE_MUTEX(msu_buffer_mutex); /** * struct msu_buffer_entry - internal MSU buffer bookkeeping * @entry: link to msu_buffer_list * @mbuf: MSU buffer object * @owner: module that provides this MSU buffer */ struct msu_buffer_entry { struct list_head entry; const struct msu_buffer *mbuf; struct module *owner; }; static struct msu_buffer_entry *__msu_buffer_entry_find(const char *name) { struct msu_buffer_entry *mbe; lockdep_assert_held(&msu_buffer_mutex); list_for_each_entry(mbe, &msu_buffer_list, entry) { if (!strcmp(mbe->mbuf->name, name)) return mbe; } return NULL; } static const struct msu_buffer * msu_buffer_get(const char *name) { struct msu_buffer_entry *mbe; mutex_lock(&msu_buffer_mutex); mbe = __msu_buffer_entry_find(name); if (mbe && !try_module_get(mbe->owner)) mbe = NULL; mutex_unlock(&msu_buffer_mutex); return mbe ? mbe->mbuf : NULL; } static void msu_buffer_put(const struct msu_buffer *mbuf) { struct msu_buffer_entry *mbe; mutex_lock(&msu_buffer_mutex); mbe = __msu_buffer_entry_find(mbuf->name); if (mbe) module_put(mbe->owner); mutex_unlock(&msu_buffer_mutex); } int intel_th_msu_buffer_register(const struct msu_buffer *mbuf, struct module *owner) { struct msu_buffer_entry *mbe; int ret = 0; mbe = kzalloc(sizeof(*mbe), GFP_KERNEL); if (!mbe) return -ENOMEM; mutex_lock(&msu_buffer_mutex); if (__msu_buffer_entry_find(mbuf->name)) { ret = -EEXIST; kfree(mbe); goto unlock; } mbe->mbuf = mbuf; mbe->owner = owner; list_add_tail(&mbe->entry, &msu_buffer_list); unlock: mutex_unlock(&msu_buffer_mutex); return ret; } EXPORT_SYMBOL_GPL(intel_th_msu_buffer_register); void intel_th_msu_buffer_unregister(const struct msu_buffer *mbuf) { struct msu_buffer_entry *mbe; mutex_lock(&msu_buffer_mutex); mbe = __msu_buffer_entry_find(mbuf->name); if (mbe) { list_del(&mbe->entry); kfree(mbe); } mutex_unlock(&msu_buffer_mutex); } EXPORT_SYMBOL_GPL(intel_th_msu_buffer_unregister); static inline bool msc_block_is_empty(struct msc_block_desc *bdesc) { /* header hasn't been written */ if (!bdesc->valid_dw) return true; /* valid_dw includes the header */ if (!msc_data_sz(bdesc)) return true; return false; } static inline struct scatterlist *msc_win_base_sg(struct msc_window *win) { return win->sgt->sgl; } static inline struct msc_block_desc *msc_win_base(struct msc_window *win) { return sg_virt(msc_win_base_sg(win)); } static inline dma_addr_t msc_win_base_dma(struct msc_window *win) { return sg_dma_address(msc_win_base_sg(win)); } static inline unsigned long msc_win_base_pfn(struct msc_window *win) { return PFN_DOWN(msc_win_base_dma(win)); } /** * msc_is_last_win() - check if a window is the last one for a given MSC * @win: window * Return: true if @win is the last window in MSC's multiblock buffer */ static inline bool msc_is_last_win(struct msc_window *win) { return win->entry.next == &win->msc->win_list; } /** * msc_next_window() - return next window in the multiblock buffer * @win: current window * * Return: window following the current one */ static struct msc_window *msc_next_window(struct msc_window *win) { if (msc_is_last_win(win)) return list_first_entry(&win->msc->win_list, struct msc_window, entry); return list_next_entry(win, entry); } static size_t msc_win_total_sz(struct msc_window *win) { struct scatterlist *sg; unsigned int blk; size_t size = 0; for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) { struct msc_block_desc *bdesc = sg_virt(sg); if (msc_block_wrapped(bdesc)) return (size_t)win->nr_blocks << PAGE_SHIFT; size += msc_total_sz(bdesc); if (msc_block_last_written(bdesc)) break; } return size; } /** * msc_find_window() - find a window matching a given sg_table * @msc: MSC device * @sgt: SG table of the window * @nonempty: skip over empty windows * * Return: MSC window structure pointer or NULL if the window * could not be found. */ static struct msc_window * msc_find_window(struct msc *msc, struct sg_table *sgt, bool nonempty) { struct msc_window *win; unsigned int found = 0; if (list_empty(&msc->win_list)) return NULL; /* * we might need a radix tree for this, depending on how * many windows a typical user would allocate; ideally it's * something like 2, in which case we're good */ list_for_each_entry(win, &msc->win_list, entry) { if (win->sgt == sgt) found++; /* skip the empty ones */ if (nonempty && msc_block_is_empty(msc_win_base(win))) continue; if (found) return win; } return NULL; } /** * msc_oldest_window() - locate the window with oldest data * @msc: MSC device * * This should only be used in multiblock mode. Caller should hold the * msc::user_count reference. * * Return: the oldest window with valid data */ static struct msc_window *msc_oldest_window(struct msc *msc) { struct msc_window *win; if (list_empty(&msc->win_list)) return NULL; win = msc_find_window(msc, msc_next_window(msc->cur_win)->sgt, true); if (win) return win; return list_first_entry(&msc->win_list, struct msc_window, entry); } /** * msc_win_oldest_sg() - locate the oldest block in a given window * @win: window to look at * * Return: index of the block with the oldest data */ static struct scatterlist *msc_win_oldest_sg(struct msc_window *win) { unsigned int blk; struct scatterlist *sg; struct msc_block_desc *bdesc = msc_win_base(win); /* without wrapping, first block is the oldest */ if (!msc_block_wrapped(bdesc)) return msc_win_base_sg(win); /* * with wrapping, last written block contains both the newest and the * oldest data for this window. */ for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) { struct msc_block_desc *bdesc = sg_virt(sg); if (msc_block_last_written(bdesc)) return sg; } return msc_win_base_sg(win); } static struct msc_block_desc *msc_iter_bdesc(struct msc_iter *iter) { return sg_virt(iter->block); } static struct msc_iter *msc_iter_install(struct msc *msc) { struct msc_iter *iter; iter = kzalloc(sizeof(*iter), GFP_KERNEL); if (!iter) return ERR_PTR(-ENOMEM); mutex_lock(&msc->buf_mutex); /* * Reading and tracing are mutually exclusive; if msc is * enabled, open() will fail; otherwise existing readers * will prevent enabling the msc and the rest of fops don't * need to worry about it. */ if (msc->enabled) { kfree(iter); iter = ERR_PTR(-EBUSY); goto unlock; } iter->msc = msc; list_add_tail(&iter->entry, &msc->iter_list); unlock: mutex_unlock(&msc->buf_mutex); return iter; } static void msc_iter_remove(struct msc_iter *iter, struct msc *msc) { mutex_lock(&msc->buf_mutex); list_del(&iter->entry); mutex_unlock(&msc->buf_mutex); kfree(iter); } static void msc_iter_block_start(struct msc_iter *iter) { if (iter->start_block) return; iter->start_block = msc_win_oldest_sg(iter->win); iter->block = iter->start_block; iter->wrap_count = 0; /* * start with the block with oldest data; if data has wrapped * in this window, it should be in this block */ if (msc_block_wrapped(msc_iter_bdesc(iter))) iter->wrap_count = 2; } static int msc_iter_win_start(struct msc_iter *iter, struct msc *msc) { /* already started, nothing to do */ if (iter->start_win) return 0; iter->start_win = msc_oldest_window(msc); if (!iter->start_win) return -EINVAL; iter->win = iter->start_win; iter->start_block = NULL; msc_iter_block_start(iter); return 0; } static int msc_iter_win_advance(struct msc_iter *iter) { iter->win = msc_next_window(iter->win); iter->start_block = NULL; if (iter->win == iter->start_win) { iter->eof++; return 1; } msc_iter_block_start(iter); return 0; } static int msc_iter_block_advance(struct msc_iter *iter) { iter->block_off = 0; /* wrapping */ if (iter->wrap_count && iter->block == iter->start_block) { iter->wrap_count--; if (!iter->wrap_count) /* copied newest data from the wrapped block */ return msc_iter_win_advance(iter); } /* no wrapping, check for last written block */ if (!iter->wrap_count && msc_block_last_written(msc_iter_bdesc(iter))) /* copied newest data for the window */ return msc_iter_win_advance(iter); /* block advance */ if (sg_is_last(iter->block)) iter->block = msc_win_base_sg(iter->win); else iter->block = sg_next(iter->block); /* no wrapping, sanity check in case there is no last written block */ if (!iter->wrap_count && iter->block == iter->start_block) return msc_iter_win_advance(iter); return 0; } /** * msc_buffer_iterate() - go through multiblock buffer's data * @iter: iterator structure * @size: amount of data to scan * @data: callback's private data * @fn: iterator callback * * This will start at the window which will be written to next (containing * the oldest data) and work its way to the current window, calling @fn * for each chunk of data as it goes. * * Caller should have msc::user_count reference to make sure the buffer * doesn't disappear from under us. * * Return: amount of data actually scanned. */ static ssize_t msc_buffer_iterate(struct msc_iter *iter, size_t size, void *data, unsigned long (*fn)(void *, void *, size_t)) { struct msc *msc = iter->msc; size_t len = size; unsigned int advance; if (iter->eof) return 0; /* start with the oldest window */ if (msc_iter_win_start(iter, msc)) return 0; do { unsigned long data_bytes = msc_data_sz(msc_iter_bdesc(iter)); void *src = (void *)msc_iter_bdesc(iter) + MSC_BDESC; size_t tocopy = data_bytes, copied = 0; size_t remaining = 0; advance = 1; /* * If block wrapping happened, we need to visit the last block * twice, because it contains both the oldest and the newest * data in this window. * * First time (wrap_count==2), in the very beginning, to collect * the oldest data, which is in the range * (data_bytes..DATA_IN_PAGE). * * Second time (wrap_count==1), it's just like any other block, * containing data in the range of [MSC_BDESC..data_bytes]. */ if (iter->block == iter->start_block && iter->wrap_count == 2) { tocopy = DATA_IN_PAGE - data_bytes; src += data_bytes; } if (!tocopy) goto next_block; tocopy -= iter->block_off; src += iter->block_off; if (len < tocopy) { tocopy = len; advance = 0; } remaining = fn(data, src, tocopy); if (remaining) advance = 0; copied = tocopy - remaining; len -= copied; iter->block_off += copied; iter->offset += copied; if (!advance) break; next_block: if (msc_iter_block_advance(iter)) break; } while (len); return size - len; } /** * msc_buffer_clear_hw_header() - clear hw header for multiblock * @msc: MSC device */ static void msc_buffer_clear_hw_header(struct msc *msc) { struct msc_window *win; struct scatterlist *sg; list_for_each_entry(win, &msc->win_list, entry) { unsigned int blk; size_t hw_sz = sizeof(struct msc_block_desc) - offsetof(struct msc_block_desc, hw_tag); for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) { struct msc_block_desc *bdesc = sg_virt(sg); memset(&bdesc->hw_tag, 0, hw_sz); } } } static int intel_th_msu_init(struct msc *msc) { u32 mintctl, msusts; if (!msc->do_irq) return 0; if (!msc->mbuf) return 0; mintctl = ioread32(msc->msu_base + REG_MSU_MINTCTL); mintctl |= msc->index ? M1BLIE : M0BLIE; iowrite32(mintctl, msc->msu_base + REG_MSU_MINTCTL); if (mintctl != ioread32(msc->msu_base + REG_MSU_MINTCTL)) { dev_info(msc_dev(msc), "MINTCTL ignores writes: no usable interrupts\n"); msc->do_irq = 0; return 0; } msusts = ioread32(msc->msu_base + REG_MSU_MSUSTS); iowrite32(msusts, msc->msu_base + REG_MSU_MSUSTS); return 0; } static void intel_th_msu_deinit(struct msc *msc) { u32 mintctl; if (!msc->do_irq) return; mintctl = ioread32(msc->msu_base + REG_MSU_MINTCTL); mintctl &= msc->index ? ~M1BLIE : ~M0BLIE; iowrite32(mintctl, msc->msu_base + REG_MSU_MINTCTL); } static int msc_win_set_lockout(struct msc_window *win, enum lockout_state expect, enum lockout_state new) { enum lockout_state old; unsigned long flags; int ret = 0; if (!win->msc->mbuf) return 0; spin_lock_irqsave(&win->lo_lock, flags); old = win->lockout; if (old != expect) { ret = -EINVAL; goto unlock; } win->lockout = new; if (old == expect && new == WIN_LOCKED) atomic_inc(&win->msc->user_count); else if (old == expect && old == WIN_LOCKED) atomic_dec(&win->msc->user_count); unlock: spin_unlock_irqrestore(&win->lo_lock, flags); if (ret) { if (expect == WIN_READY && old == WIN_LOCKED) return -EBUSY; /* from intel_th_msc_window_unlock(), don't warn if not locked */ if (expect == WIN_LOCKED && old == new) return 0; dev_warn_ratelimited(msc_dev(win->msc), "expected lockout state %d, got %d\n", expect, old); } return ret; } /** * msc_configure() - set up MSC hardware * @msc: the MSC device to configure * * Program storage mode, wrapping, burst length and trace buffer address * into a given MSC. Then, enable tracing and set msc::enabled. * The latter is serialized on msc::buf_mutex, so make sure to hold it. */ static int msc_configure(struct msc *msc) { u32 reg; lockdep_assert_held(&msc->buf_mutex); if (msc->mode > MSC_MODE_MULTI) return -EINVAL; if (msc->mode == MSC_MODE_MULTI) { if (msc_win_set_lockout(msc->cur_win, WIN_READY, WIN_INUSE)) return -EBUSY; msc_buffer_clear_hw_header(msc); } msc->orig_addr = ioread32(msc->reg_base + REG_MSU_MSC0BAR); msc->orig_sz = ioread32(msc->reg_base + REG_MSU_MSC0SIZE); reg = msc->base_addr >> PAGE_SHIFT; iowrite32(reg, msc->reg_base + REG_MSU_MSC0BAR); if (msc->mode == MSC_MODE_SINGLE) { reg = msc->nr_pages; iowrite32(reg, msc->reg_base + REG_MSU_MSC0SIZE); } reg = ioread32(msc->reg_base + REG_MSU_MSC0CTL); reg &= ~(MSC_MODE | MSC_WRAPEN | MSC_EN | MSC_RD_HDR_OVRD); reg |= MSC_EN; reg |= msc->mode << __ffs(MSC_MODE); reg |= msc->burst_len << __ffs(MSC_LEN); if (msc->wrap) reg |= MSC_WRAPEN; iowrite32(reg, msc->reg_base + REG_MSU_MSC0CTL); intel_th_msu_init(msc); msc->thdev->output.multiblock = msc->mode == MSC_MODE_MULTI; intel_th_trace_enable(msc->thdev); msc->enabled = 1; if (msc->mbuf && msc->mbuf->activate) msc->mbuf->activate(msc->mbuf_priv); return 0; } /** * msc_disable() - disable MSC hardware * @msc: MSC device to disable * * If @msc is enabled, disable tracing on the switch and then disable MSC * storage. Caller must hold msc::buf_mutex. */ static void msc_disable(struct msc *msc) { struct msc_window *win = msc->cur_win; u32 reg; lockdep_assert_held(&msc->buf_mutex); if (msc->mode == MSC_MODE_MULTI) msc_win_set_lockout(win, WIN_INUSE, WIN_LOCKED); if (msc->mbuf && msc->mbuf->deactivate) msc->mbuf->deactivate(msc->mbuf_priv); intel_th_msu_deinit(msc); intel_th_trace_disable(msc->thdev); if (msc->mode == MSC_MODE_SINGLE) { reg = ioread32(msc->reg_base + REG_MSU_MSC0STS); msc->single_wrap = !!(reg & MSCSTS_WRAPSTAT); reg = ioread32(msc->reg_base + REG_MSU_MSC0MWP); msc->single_sz = reg & ((msc->nr_pages << PAGE_SHIFT) - 1); dev_dbg(msc_dev(msc), "MSCnMWP: %08x/%08lx, wrap: %d\n", reg, msc->single_sz, msc->single_wrap); } reg = ioread32(msc->reg_base + REG_MSU_MSC0CTL); reg &= ~MSC_EN; iowrite32(reg, msc->reg_base + REG_MSU_MSC0CTL); if (msc->mbuf && msc->mbuf->ready) msc->mbuf->ready(msc->mbuf_priv, win->sgt, msc_win_total_sz(win)); msc->enabled = 0; iowrite32(msc->orig_addr, msc->reg_base + REG_MSU_MSC0BAR); iowrite32(msc->orig_sz, msc->reg_base + REG_MSU_MSC0SIZE); dev_dbg(msc_dev(msc), "MSCnNWSA: %08x\n", ioread32(msc->reg_base + REG_MSU_MSC0NWSA)); reg = ioread32(msc->reg_base + REG_MSU_MSC0STS); dev_dbg(msc_dev(msc), "MSCnSTS: %08x\n", reg); reg = ioread32(msc->reg_base + REG_MSU_MSUSTS); reg &= msc->index ? MSUSTS_MSC1BLAST : MSUSTS_MSC0BLAST; iowrite32(reg, msc->reg_base + REG_MSU_MSUSTS); } static int intel_th_msc_activate(struct intel_th_device *thdev) { struct msc *msc = dev_get_drvdata(&thdev->dev); int ret = -EBUSY; if (!atomic_inc_unless_negative(&msc->user_count)) return -ENODEV; mutex_lock(&msc->buf_mutex); /* if there are readers, refuse */ if (list_empty(&msc->iter_list)) ret = msc_configure(msc); mutex_unlock(&msc->buf_mutex); if (ret) atomic_dec(&msc->user_count); return ret; } static void intel_th_msc_deactivate(struct intel_th_device *thdev) { struct msc *msc = dev_get_drvdata(&thdev->dev); mutex_lock(&msc->buf_mutex); if (msc->enabled) { msc_disable(msc); atomic_dec(&msc->user_count); } mutex_unlock(&msc->buf_mutex); } /** * msc_buffer_contig_alloc() - allocate a contiguous buffer for SINGLE mode * @msc: MSC device * @size: allocation size in bytes * * This modifies msc::base, which requires msc::buf_mutex to serialize, so the * caller is expected to hold it. * * Return: 0 on success, -errno otherwise. */ static int msc_buffer_contig_alloc(struct msc *msc, unsigned long size) { unsigned long nr_pages = size >> PAGE_SHIFT; unsigned int order = get_order(size); struct page *page; int ret; if (!size) return 0; ret = sg_alloc_table(&msc->single_sgt, 1, GFP_KERNEL); if (ret) goto err_out; ret = -ENOMEM; page = alloc_pages(GFP_KERNEL | __GFP_ZERO | GFP_DMA32, order); if (!page) goto err_free_sgt; split_page(page, order); sg_set_buf(msc->single_sgt.sgl, page_address(page), size); ret = dma_map_sg(msc_dev(msc)->parent->parent, msc->single_sgt.sgl, 1, DMA_FROM_DEVICE); if (ret < 0) goto err_free_pages; msc->nr_pages = nr_pages; msc->base = page_address(page); msc->base_addr = sg_dma_address(msc->single_sgt.sgl); return 0; err_free_pages: __free_pages(page, order); err_free_sgt: sg_free_table(&msc->single_sgt); err_out: return ret; } /** * msc_buffer_contig_free() - free a contiguous buffer * @msc: MSC configured in SINGLE mode */ static void msc_buffer_contig_free(struct msc *msc) { unsigned long off; dma_unmap_sg(msc_dev(msc)->parent->parent, msc->single_sgt.sgl, 1, DMA_FROM_DEVICE); sg_free_table(&msc->single_sgt); for (off = 0; off < msc->nr_pages << PAGE_SHIFT; off += PAGE_SIZE) { struct page *page = virt_to_page(msc->base + off); page->mapping = NULL; __free_page(page); } msc->nr_pages = 0; } /** * msc_buffer_contig_get_page() - find a page at a given offset * @msc: MSC configured in SINGLE mode * @pgoff: page offset * * Return: page, if @pgoff is within the range, NULL otherwise. */ static struct page *msc_buffer_contig_get_page(struct msc *msc, unsigned long pgoff) { if (pgoff >= msc->nr_pages) return NULL; return virt_to_page(msc->base + (pgoff << PAGE_SHIFT)); } static int __msc_buffer_win_alloc(struct msc_window *win, unsigned int nr_segs) { struct scatterlist *sg_ptr; void *block; int i, ret; ret = sg_alloc_table(win->sgt, nr_segs, GFP_KERNEL); if (ret) return -ENOMEM; for_each_sg(win->sgt->sgl, sg_ptr, nr_segs, i) { block = dma_alloc_coherent(msc_dev(win->msc)->parent->parent, PAGE_SIZE, &sg_dma_address(sg_ptr), GFP_KERNEL); if (!block) goto err_nomem; sg_set_buf(sg_ptr, block, PAGE_SIZE); } return nr_segs; err_nomem: for_each_sg(win->sgt->sgl, sg_ptr, i, ret) dma_free_coherent(msc_dev(win->msc)->parent->parent, PAGE_SIZE, sg_virt(sg_ptr), sg_dma_address(sg_ptr)); sg_free_table(win->sgt); return -ENOMEM; } #ifdef CONFIG_X86 static void msc_buffer_set_uc(struct msc_window *win, unsigned int nr_segs) { struct scatterlist *sg_ptr; int i; for_each_sg(win->sgt->sgl, sg_ptr, nr_segs, i) { /* Set the page as uncached */ set_memory_uc((unsigned long)sg_virt(sg_ptr), PFN_DOWN(sg_ptr->length)); } } static void msc_buffer_set_wb(struct msc_window *win) { struct scatterlist *sg_ptr; int i; for_each_sg(win->sgt->sgl, sg_ptr, win->nr_segs, i) { /* Reset the page to write-back */ set_memory_wb((unsigned long)sg_virt(sg_ptr), PFN_DOWN(sg_ptr->length)); } } #else /* !X86 */ static inline void msc_buffer_set_uc(struct msc_window *win, unsigned int nr_segs) {} static inline void msc_buffer_set_wb(struct msc_window *win) {} #endif /* CONFIG_X86 */ /** * msc_buffer_win_alloc() - alloc a window for a multiblock mode * @msc: MSC device * @nr_blocks: number of pages in this window * * This modifies msc::win_list and msc::base, which requires msc::buf_mutex * to serialize, so the caller is expected to hold it. * * Return: 0 on success, -errno otherwise. */ static int msc_buffer_win_alloc(struct msc *msc, unsigned int nr_blocks) { struct msc_window *win; int ret = -ENOMEM; if (!nr_blocks) return 0; win = kzalloc(sizeof(*win), GFP_KERNEL); if (!win) return -ENOMEM; win->msc = msc; win->sgt = &win->_sgt; win->lockout = WIN_READY; spin_lock_init(&win->lo_lock); if (!list_empty(&msc->win_list)) { struct msc_window *prev = list_last_entry(&msc->win_list, struct msc_window, entry); win->pgoff = prev->pgoff + prev->nr_blocks; } if (msc->mbuf && msc->mbuf->alloc_window) ret = msc->mbuf->alloc_window(msc->mbuf_priv, &win->sgt, nr_blocks << PAGE_SHIFT); else ret = __msc_buffer_win_alloc(win, nr_blocks); if (ret <= 0) goto err_nomem; msc_buffer_set_uc(win, ret); win->nr_segs = ret; win->nr_blocks = nr_blocks; if (list_empty(&msc->win_list)) { msc->base = msc_win_base(win); msc->base_addr = msc_win_base_dma(win); msc->cur_win = win; } list_add_tail(&win->entry, &msc->win_list); msc->nr_pages += nr_blocks; return 0; err_nomem: kfree(win); return ret; } static void __msc_buffer_win_free(struct msc *msc, struct msc_window *win) { struct scatterlist *sg; int i; for_each_sg(win->sgt->sgl, sg, win->nr_segs, i) { struct page *page = sg_page(sg); page->mapping = NULL; dma_free_coherent(msc_dev(win->msc)->parent->parent, PAGE_SIZE, sg_virt(sg), sg_dma_address(sg)); } sg_free_table(win->sgt); } /** * msc_buffer_win_free() - free a window from MSC's window list * @msc: MSC device * @win: window to free * * This modifies msc::win_list and msc::base, which requires msc::buf_mutex * to serialize, so the caller is expected to hold it. */ static void msc_buffer_win_free(struct msc *msc, struct msc_window *win) { msc->nr_pages -= win->nr_blocks; list_del(&win->entry); if (list_empty(&msc->win_list)) { msc->base = NULL; msc->base_addr = 0; } msc_buffer_set_wb(win); if (msc->mbuf && msc->mbuf->free_window) msc->mbuf->free_window(msc->mbuf_priv, win->sgt); else __msc_buffer_win_free(msc, win); kfree(win); } /** * msc_buffer_relink() - set up block descriptors for multiblock mode * @msc: MSC device * * This traverses msc::win_list, which requires msc::buf_mutex to serialize, * so the caller is expected to hold it. */ static void msc_buffer_relink(struct msc *msc) { struct msc_window *win, *next_win; /* call with msc::mutex locked */ list_for_each_entry(win, &msc->win_list, entry) { struct scatterlist *sg; unsigned int blk; u32 sw_tag = 0; /* * Last window's next_win should point to the first window * and MSC_SW_TAG_LASTWIN should be set. */ if (msc_is_last_win(win)) { sw_tag |= MSC_SW_TAG_LASTWIN; next_win = list_first_entry(&msc->win_list, struct msc_window, entry); } else { next_win = list_next_entry(win, entry); } for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) { struct msc_block_desc *bdesc = sg_virt(sg); memset(bdesc, 0, sizeof(*bdesc)); bdesc->next_win = msc_win_base_pfn(next_win); /* * Similarly to last window, last block should point * to the first one. */ if (blk == win->nr_segs - 1) { sw_tag |= MSC_SW_TAG_LASTBLK; bdesc->next_blk = msc_win_base_pfn(win); } else { dma_addr_t addr = sg_dma_address(sg_next(sg)); bdesc->next_blk = PFN_DOWN(addr); } bdesc->sw_tag = sw_tag; bdesc->block_sz = sg->length / 64; } } /* * Make the above writes globally visible before tracing is * enabled to make sure hardware sees them coherently. */ wmb(); } static void msc_buffer_multi_free(struct msc *msc) { struct msc_window *win, *iter; list_for_each_entry_safe(win, iter, &msc->win_list, entry) msc_buffer_win_free(msc, win); } static int msc_buffer_multi_alloc(struct msc *msc, unsigned long *nr_pages, unsigned int nr_wins) { int ret, i; for (i = 0; i < nr_wins; i++) { ret = msc_buffer_win_alloc(msc, nr_pages[i]); if (ret) { msc_buffer_multi_free(msc); return ret; } } msc_buffer_relink(msc); return 0; } /** * msc_buffer_free() - free buffers for MSC * @msc: MSC device * * Free MSC's storage buffers. * * This modifies msc::win_list and msc::base, which requires msc::buf_mutex to * serialize, so the caller is expected to hold it. */ static void msc_buffer_free(struct msc *msc) { if (msc->mode == MSC_MODE_SINGLE) msc_buffer_contig_free(msc); else if (msc->mode == MSC_MODE_MULTI) msc_buffer_multi_free(msc); } /** * msc_buffer_alloc() - allocate a buffer for MSC * @msc: MSC device * @size: allocation size in bytes * * Allocate a storage buffer for MSC, depending on the msc::mode, it will be * either done via msc_buffer_contig_alloc() for SINGLE operation mode or * msc_buffer_win_alloc() for multiblock operation. The latter allocates one * window per invocation, so in multiblock mode this can be called multiple * times for the same MSC to allocate multiple windows. * * This modifies msc::win_list and msc::base, which requires msc::buf_mutex * to serialize, so the caller is expected to hold it. * * Return: 0 on success, -errno otherwise. */ static int msc_buffer_alloc(struct msc *msc, unsigned long *nr_pages, unsigned int nr_wins) { int ret; /* -1: buffer not allocated */ if (atomic_read(&msc->user_count) != -1) return -EBUSY; if (msc->mode == MSC_MODE_SINGLE) { if (nr_wins != 1) return -EINVAL; ret = msc_buffer_contig_alloc(msc, nr_pages[0] << PAGE_SHIFT); } else if (msc->mode == MSC_MODE_MULTI) { ret = msc_buffer_multi_alloc(msc, nr_pages, nr_wins); } else { ret = -EINVAL; } if (!ret) { /* allocation should be visible before the counter goes to 0 */ smp_mb__before_atomic(); if (WARN_ON_ONCE(atomic_cmpxchg(&msc->user_count, -1, 0) != -1)) return -EINVAL; } return ret; } /** * msc_buffer_unlocked_free_unless_used() - free a buffer unless it's in use * @msc: MSC device * * This will free MSC buffer unless it is in use or there is no allocated * buffer. * Caller needs to hold msc::buf_mutex. * * Return: 0 on successful deallocation or if there was no buffer to * deallocate, -EBUSY if there are active users. */ static int msc_buffer_unlocked_free_unless_used(struct msc *msc) { int count, ret = 0; count = atomic_cmpxchg(&msc->user_count, 0, -1); /* > 0: buffer is allocated and has users */ if (count > 0) ret = -EBUSY; /* 0: buffer is allocated, no users */ else if (!count) msc_buffer_free(msc); /* < 0: no buffer, nothing to do */ return ret; } /** * msc_buffer_free_unless_used() - free a buffer unless it's in use * @msc: MSC device * * This is a locked version of msc_buffer_unlocked_free_unless_used(). */ static int msc_buffer_free_unless_used(struct msc *msc) { int ret; mutex_lock(&msc->buf_mutex); ret = msc_buffer_unlocked_free_unless_used(msc); mutex_unlock(&msc->buf_mutex); return ret; } /** * msc_buffer_get_page() - get MSC buffer page at a given offset * @msc: MSC device * @pgoff: page offset into the storage buffer * * This traverses msc::win_list, so holding msc::buf_mutex is expected from * the caller. * * Return: page if @pgoff corresponds to a valid buffer page or NULL. */ static struct page *msc_buffer_get_page(struct msc *msc, unsigned long pgoff) { struct msc_window *win; struct scatterlist *sg; unsigned int blk; if (msc->mode == MSC_MODE_SINGLE) return msc_buffer_contig_get_page(msc, pgoff); list_for_each_entry(win, &msc->win_list, entry) if (pgoff >= win->pgoff && pgoff < win->pgoff + win->nr_blocks) goto found; return NULL; found: pgoff -= win->pgoff; for_each_sg(win->sgt->sgl, sg, win->nr_segs, blk) { struct page *page = sg_page(sg); size_t pgsz = PFN_DOWN(sg->length); if (pgoff < pgsz) return page + pgoff; pgoff -= pgsz; } return NULL; } /** * struct msc_win_to_user_struct - data for copy_to_user() callback * @buf: userspace buffer to copy data to * @offset: running offset */ struct msc_win_to_user_struct { char __user *buf; unsigned long offset; }; /** * msc_win_to_user() - iterator for msc_buffer_iterate() to copy data to user * @data: callback's private data * @src: source buffer * @len: amount of data to copy from the source buffer */ static unsigned long msc_win_to_user(void *data, void *src, size_t len) { struct msc_win_to_user_struct *u = data; unsigned long ret; ret = copy_to_user(u->buf + u->offset, src, len); u->offset += len - ret; return ret; } /* * file operations' callbacks */ static int intel_th_msc_open(struct inode *inode, struct file *file) { struct intel_th_device *thdev = file->private_data; struct msc *msc = dev_get_drvdata(&thdev->dev); struct msc_iter *iter; if (!capable(CAP_SYS_RAWIO)) return -EPERM; iter = msc_iter_install(msc); if (IS_ERR(iter)) return PTR_ERR(iter); file->private_data = iter; return nonseekable_open(inode, file); } static int intel_th_msc_release(struct inode *inode, struct file *file) { struct msc_iter *iter = file->private_data; struct msc *msc = iter->msc; msc_iter_remove(iter, msc); return 0; } static ssize_t msc_single_to_user(struct msc *msc, char __user *buf, loff_t off, size_t len) { unsigned long size = msc->nr_pages << PAGE_SHIFT, rem = len; unsigned long start = off, tocopy = 0; if (msc->single_wrap) { start += msc->single_sz; if (start < size) { tocopy = min(rem, size - start); if (copy_to_user(buf, msc->base + start, tocopy)) return -EFAULT; buf += tocopy; rem -= tocopy; start += tocopy; } start &= size - 1; if (rem) { tocopy = min(rem, msc->single_sz - start); if (copy_to_user(buf, msc->base + start, tocopy)) return -EFAULT; rem -= tocopy; } return len - rem; } if (copy_to_user(buf, msc->base + start, rem)) return -EFAULT; return len; } static ssize_t intel_th_msc_read(struct file *file, char __user *buf, size_t len, loff_t *ppos) { struct msc_iter *iter = file->private_data; struct msc *msc = iter->msc; size_t size; loff_t off = *ppos; ssize_t ret = 0; if (!atomic_inc_unless_negative(&msc->user_count)) return 0; if (msc->mode == MSC_MODE_SINGLE && !msc->single_wrap) size = msc->single_sz; else size = msc->nr_pages << PAGE_SHIFT; if (!size) goto put_count; if (off >= size) goto put_count; if (off + len >= size) len = size - off; if (msc->mode == MSC_MODE_SINGLE) { ret = msc_single_to_user(msc, buf, off, len); if (ret >= 0) *ppos += ret; } else if (msc->mode == MSC_MODE_MULTI) { struct msc_win_to_user_struct u = { .buf = buf, .offset = 0, }; ret = msc_buffer_iterate(iter, len, &u, msc_win_to_user); if (ret >= 0) *ppos = iter->offset; } else { ret = -EINVAL; } put_count: atomic_dec(&msc->user_count); return ret; } /* * vm operations callbacks (vm_ops) */ static void msc_mmap_open(struct vm_area_struct *vma) { struct msc_iter *iter = vma->vm_file->private_data; struct msc *msc = iter->msc; atomic_inc(&msc->mmap_count); } static void msc_mmap_close(struct vm_area_struct *vma) { struct msc_iter *iter = vma->vm_file->private_data; struct msc *msc = iter->msc; unsigned long pg; if (!atomic_dec_and_mutex_lock(&msc->mmap_count, &msc->buf_mutex)) return; /* drop page _refcounts */ for (pg = 0; pg < msc->nr_pages; pg++) { struct page *page = msc_buffer_get_page(msc, pg); if (WARN_ON_ONCE(!page)) continue; if (page->mapping) page->mapping = NULL; } /* last mapping -- drop user_count */ atomic_dec(&msc->user_count); mutex_unlock(&msc->buf_mutex); } static vm_fault_t msc_mmap_fault(struct vm_fault *vmf) { struct msc_iter *iter = vmf->vma->vm_file->private_data; struct msc *msc = iter->msc; vmf->page = msc_buffer_get_page(msc, vmf->pgoff); if (!vmf->page) return VM_FAULT_SIGBUS; get_page(vmf->page); vmf->page->mapping = vmf->vma->vm_file->f_mapping; vmf->page->index = vmf->pgoff; return 0; } static const struct vm_operations_struct msc_mmap_ops = { .open = msc_mmap_open, .close = msc_mmap_close, .fault = msc_mmap_fault, }; static int intel_th_msc_mmap(struct file *file, struct vm_area_struct *vma) { unsigned long size = vma->vm_end - vma->vm_start; struct msc_iter *iter = vma->vm_file->private_data; struct msc *msc = iter->msc; int ret = -EINVAL; if (!size || offset_in_page(size)) return -EINVAL; if (vma->vm_pgoff) return -EINVAL; /* grab user_count once per mmap; drop in msc_mmap_close() */ if (!atomic_inc_unless_negative(&msc->user_count)) return -EINVAL; if (msc->mode != MSC_MODE_SINGLE && msc->mode != MSC_MODE_MULTI) goto out; if (size >> PAGE_SHIFT != msc->nr_pages) goto out; atomic_set(&msc->mmap_count, 1); ret = 0; out: if (ret) atomic_dec(&msc->user_count); vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); vma->vm_flags |= VM_DONTEXPAND | VM_DONTCOPY; vma->vm_ops = &msc_mmap_ops; return ret; } static const struct file_operations intel_th_msc_fops = { .open = intel_th_msc_open, .release = intel_th_msc_release, .read = intel_th_msc_read, .mmap = intel_th_msc_mmap, .llseek = no_llseek, .owner = THIS_MODULE, }; static void intel_th_msc_wait_empty(struct intel_th_device *thdev) { struct msc *msc = dev_get_drvdata(&thdev->dev); unsigned long count; u32 reg; for (reg = 0, count = MSC_PLE_WAITLOOP_DEPTH; count && !(reg & MSCSTS_PLE); count--) { reg = __raw_readl(msc->reg_base + REG_MSU_MSC0STS); cpu_relax(); } if (!count) dev_dbg(msc_dev(msc), "timeout waiting for MSC0 PLE\n"); } static int intel_th_msc_init(struct msc *msc) { atomic_set(&msc->user_count, -1); msc->mode = msc->multi_is_broken ? MSC_MODE_SINGLE : MSC_MODE_MULTI; mutex_init(&msc->buf_mutex); INIT_LIST_HEAD(&msc->win_list); INIT_LIST_HEAD(&msc->iter_list); msc->burst_len = (ioread32(msc->reg_base + REG_MSU_MSC0CTL) & MSC_LEN) >> __ffs(MSC_LEN); return 0; } static int msc_win_switch(struct msc *msc) { struct msc_window *first; if (list_empty(&msc->win_list)) return -EINVAL; first = list_first_entry(&msc->win_list, struct msc_window, entry); if (msc_is_last_win(msc->cur_win)) msc->cur_win = first; else msc->cur_win = list_next_entry(msc->cur_win, entry); msc->base = msc_win_base(msc->cur_win); msc->base_addr = msc_win_base_dma(msc->cur_win); intel_th_trace_switch(msc->thdev); return 0; } /** * intel_th_msc_window_unlock - put the window back in rotation * @dev: MSC device to which this relates * @sgt: buffer's sg_table for the window, does nothing if NULL */ void intel_th_msc_window_unlock(struct device *dev, struct sg_table *sgt) { struct msc *msc = dev_get_drvdata(dev); struct msc_window *win; if (!sgt) return; win = msc_find_window(msc, sgt, false); if (!win) return; msc_win_set_lockout(win, WIN_LOCKED, WIN_READY); if (msc->switch_on_unlock == win) { msc->switch_on_unlock = NULL; msc_win_switch(msc); } } EXPORT_SYMBOL_GPL(intel_th_msc_window_unlock); static void msc_work(struct work_struct *work) { struct msc *msc = container_of(work, struct msc, work); intel_th_msc_deactivate(msc->thdev); } static irqreturn_t intel_th_msc_interrupt(struct intel_th_device *thdev) { struct msc *msc = dev_get_drvdata(&thdev->dev); u32 msusts = ioread32(msc->msu_base + REG_MSU_MSUSTS); u32 mask = msc->index ? MSUSTS_MSC1BLAST : MSUSTS_MSC0BLAST; struct msc_window *win, *next_win; if (!msc->do_irq || !msc->mbuf) return IRQ_NONE; msusts &= mask; if (!msusts) return msc->enabled ? IRQ_HANDLED : IRQ_NONE; iowrite32(msusts, msc->msu_base + REG_MSU_MSUSTS); if (!msc->enabled) return IRQ_NONE; /* grab the window before we do the switch */ win = msc->cur_win; if (!win) return IRQ_HANDLED; next_win = msc_next_window(win); if (!next_win) return IRQ_HANDLED; /* next window: if READY, proceed, if LOCKED, stop the trace */ if (msc_win_set_lockout(next_win, WIN_READY, WIN_INUSE)) { if (msc->stop_on_full) schedule_work(&msc->work); else msc->switch_on_unlock = next_win; return IRQ_HANDLED; } /* current window: INUSE -> LOCKED */ msc_win_set_lockout(win, WIN_INUSE, WIN_LOCKED); msc_win_switch(msc); if (msc->mbuf && msc->mbuf->ready) msc->mbuf->ready(msc->mbuf_priv, win->sgt, msc_win_total_sz(win)); return IRQ_HANDLED; } static const char * const msc_mode[] = { [MSC_MODE_SINGLE] = "single", [MSC_MODE_MULTI] = "multi", [MSC_MODE_EXI] = "ExI", [MSC_MODE_DEBUG] = "debug", }; static ssize_t wrap_show(struct device *dev, struct device_attribute *attr, char *buf) { struct msc *msc = dev_get_drvdata(dev); return scnprintf(buf, PAGE_SIZE, "%d\n", msc->wrap); } static ssize_t wrap_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct msc *msc = dev_get_drvdata(dev); unsigned long val; int ret; ret = kstrtoul(buf, 10, &val); if (ret) return ret; msc->wrap = !!val; return size; } static DEVICE_ATTR_RW(wrap); static void msc_buffer_unassign(struct msc *msc) { lockdep_assert_held(&msc->buf_mutex); if (!msc->mbuf) return; msc->mbuf->unassign(msc->mbuf_priv); msu_buffer_put(msc->mbuf); msc->mbuf_priv = NULL; msc->mbuf = NULL; } static ssize_t mode_show(struct device *dev, struct device_attribute *attr, char *buf) { struct msc *msc = dev_get_drvdata(dev); const char *mode = msc_mode[msc->mode]; ssize_t ret; mutex_lock(&msc->buf_mutex); if (msc->mbuf) mode = msc->mbuf->name; ret = scnprintf(buf, PAGE_SIZE, "%s\n", mode); mutex_unlock(&msc->buf_mutex); return ret; } static ssize_t mode_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { const struct msu_buffer *mbuf = NULL; struct msc *msc = dev_get_drvdata(dev); size_t len = size; char *cp, *mode; int i, ret; if (!capable(CAP_SYS_RAWIO)) return -EPERM; cp = memchr(buf, '\n', len); if (cp) len = cp - buf; mode = kstrndup(buf, len, GFP_KERNEL); if (!mode) return -ENOMEM; i = match_string(msc_mode, ARRAY_SIZE(msc_mode), mode); if (i >= 0) { kfree(mode); goto found; } /* Buffer sinks only work with a usable IRQ */ if (!msc->do_irq) { kfree(mode); return -EINVAL; } mbuf = msu_buffer_get(mode); kfree(mode); if (mbuf) goto found; return -EINVAL; found: if (i == MSC_MODE_MULTI && msc->multi_is_broken) return -EOPNOTSUPP; mutex_lock(&msc->buf_mutex); ret = 0; /* Same buffer: do nothing */ if (mbuf && mbuf == msc->mbuf) { /* put the extra reference we just got */ msu_buffer_put(mbuf); goto unlock; } ret = msc_buffer_unlocked_free_unless_used(msc); if (ret) goto unlock; if (mbuf) { void *mbuf_priv = mbuf->assign(dev, &i); if (!mbuf_priv) { ret = -ENOMEM; goto unlock; } msc_buffer_unassign(msc); msc->mbuf_priv = mbuf_priv; msc->mbuf = mbuf; } else { msc_buffer_unassign(msc); } msc->mode = i; unlock: if (ret && mbuf) msu_buffer_put(mbuf); mutex_unlock(&msc->buf_mutex); return ret ? ret : size; } static DEVICE_ATTR_RW(mode); static ssize_t nr_pages_show(struct device *dev, struct device_attribute *attr, char *buf) { struct msc *msc = dev_get_drvdata(dev); struct msc_window *win; size_t count = 0; mutex_lock(&msc->buf_mutex); if (msc->mode == MSC_MODE_SINGLE) count = scnprintf(buf, PAGE_SIZE, "%ld\n", msc->nr_pages); else if (msc->mode == MSC_MODE_MULTI) { list_for_each_entry(win, &msc->win_list, entry) { count += scnprintf(buf + count, PAGE_SIZE - count, "%d%c", win->nr_blocks, msc_is_last_win(win) ? '\n' : ','); } } else { count = scnprintf(buf, PAGE_SIZE, "unsupported\n"); } mutex_unlock(&msc->buf_mutex); return count; } static ssize_t nr_pages_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct msc *msc = dev_get_drvdata(dev); unsigned long val, *win = NULL, *rewin; size_t len = size; const char *p = buf; char *end, *s; int ret, nr_wins = 0; if (!capable(CAP_SYS_RAWIO)) return -EPERM; ret = msc_buffer_free_unless_used(msc); if (ret) return ret; /* scan the comma-separated list of allocation sizes */ end = memchr(buf, '\n', len); if (end) len = end - buf; do { end = memchr(p, ',', len); s = kstrndup(p, end ? end - p : len, GFP_KERNEL); if (!s) { ret = -ENOMEM; goto free_win; } ret = kstrtoul(s, 10, &val); kfree(s); if (ret || !val) goto free_win; if (nr_wins && msc->mode == MSC_MODE_SINGLE) { ret = -EINVAL; goto free_win; } nr_wins++; rewin = krealloc(win, sizeof(*win) * nr_wins, GFP_KERNEL); if (!rewin) { kfree(win); return -ENOMEM; } win = rewin; win[nr_wins - 1] = val; if (!end) break; /* consume the number and the following comma, hence +1 */ len -= end - p + 1; p = end + 1; } while (len); mutex_lock(&msc->buf_mutex); ret = msc_buffer_alloc(msc, win, nr_wins); mutex_unlock(&msc->buf_mutex); free_win: kfree(win); return ret ? ret : size; } static DEVICE_ATTR_RW(nr_pages); static ssize_t win_switch_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct msc *msc = dev_get_drvdata(dev); unsigned long val; int ret; ret = kstrtoul(buf, 10, &val); if (ret) return ret; if (val != 1) return -EINVAL; ret = -EINVAL; mutex_lock(&msc->buf_mutex); /* * Window switch can only happen in the "multi" mode. * If a external buffer is engaged, they have the full * control over window switching. */ if (msc->mode == MSC_MODE_MULTI && !msc->mbuf) ret = msc_win_switch(msc); mutex_unlock(&msc->buf_mutex); return ret ? ret : size; } static DEVICE_ATTR_WO(win_switch); static ssize_t stop_on_full_show(struct device *dev, struct device_attribute *attr, char *buf) { struct msc *msc = dev_get_drvdata(dev); return sprintf(buf, "%d\n", msc->stop_on_full); } static ssize_t stop_on_full_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct msc *msc = dev_get_drvdata(dev); int ret; ret = kstrtobool(buf, &msc->stop_on_full); if (ret) return ret; return size; } static DEVICE_ATTR_RW(stop_on_full); static struct attribute *msc_output_attrs[] = { &dev_attr_wrap.attr, &dev_attr_mode.attr, &dev_attr_nr_pages.attr, &dev_attr_win_switch.attr, &dev_attr_stop_on_full.attr, NULL, }; static struct attribute_group msc_output_group = { .attrs = msc_output_attrs, }; static int intel_th_msc_probe(struct intel_th_device *thdev) { struct device *dev = &thdev->dev; struct resource *res; struct msc *msc; void __iomem *base; int err; res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0); if (!res) return -ENODEV; base = devm_ioremap(dev, res->start, resource_size(res)); if (!base) return -ENOMEM; msc = devm_kzalloc(dev, sizeof(*msc), GFP_KERNEL); if (!msc) return -ENOMEM; res = intel_th_device_get_resource(thdev, IORESOURCE_IRQ, 1); if (!res) msc->do_irq = 1; if (INTEL_TH_CAP(to_intel_th(thdev), multi_is_broken)) msc->multi_is_broken = 1; msc->index = thdev->id; msc->thdev = thdev; msc->reg_base = base + msc->index * 0x100; msc->msu_base = base; INIT_WORK(&msc->work, msc_work); err = intel_th_msc_init(msc); if (err) return err; dev_set_drvdata(dev, msc); return 0; } static void intel_th_msc_remove(struct intel_th_device *thdev) { struct msc *msc = dev_get_drvdata(&thdev->dev); int ret; intel_th_msc_deactivate(thdev); /* * Buffers should not be used at this point except if the * output character device is still open and the parent * device gets detached from its bus, which is a FIXME. */ ret = msc_buffer_free_unless_used(msc); WARN_ON_ONCE(ret); } static struct intel_th_driver intel_th_msc_driver = { .probe = intel_th_msc_probe, .remove = intel_th_msc_remove, .irq = intel_th_msc_interrupt, .wait_empty = intel_th_msc_wait_empty, .activate = intel_th_msc_activate, .deactivate = intel_th_msc_deactivate, .fops = &intel_th_msc_fops, .attr_group = &msc_output_group, .driver = { .name = "msc", .owner = THIS_MODULE, }, }; module_driver(intel_th_msc_driver, intel_th_driver_register, intel_th_driver_unregister); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("Intel(R) Trace Hub Memory Storage Unit driver"); MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
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